Hubcaps for the Snoopy's (OH-XEA) wheels

Lauantai 27.12.2025 - Tuesday Club member

Suomeksi

The original aircraft undercarriage wheels of Snoopy (OH-XEA “Ressu”) have not survived. The undercarriage was fitted with new wheels and it turned out that the wheels of a ride-on lawnmower were a perfect fit for the axle. By coincidence, their tyres were also the same size (15 x 6.00 – 6) as those commonly used on light aircraft.

The undercarriage wheels originally fitted to the Snoopy had metal hubcaps that curved outwards, or bulged. We decided to make similar hubcaps for the wheels we are using. Thus, we needed hubcaps with a diameter of 15 cm to fit the rim. We considered various options for manufacturing them, even as far as spinning them on a lathe.

Sometimes luck lends a hand, and that’s exactly what happened here. The solution was found in the kitchen. It turned out that the lids of small stainless-steel saucepans are generally 15 cm in diameter – exactly the size of the wheel rim on the Snoopy’s undercarriage. Such steel saucepan lids were found at a flea market for 1,05 euros each. However, some modification was necessary: the knob in the centre of the saucepan lid had to be removed, and 10 mm had to be cut off the stepped edge so that the lid would fit neatly against the rim.

All that remained was to design a system for fastening the lid to the rim. We drew various alternative solutions on the paper covering the workbench. We ended up on choosing a fairly simple model and made a drawing of it. A bracket shaped like a capital 'A' with flat ends, made from sheet metal, would be fastened to the rim and reach over the end of the axle. The bracket would be secured to the rim at both ends of the 'A' using small bolts. An 8 mm bolt, inserted from underneath, would be fitted at the tip of the bracket. This bolt would protrude about half a centimetre through a hole drilled in the centre of the hubcap, allowing a nut to be tightened onto the end of the bolt.

To make the brackets, 20 mm wide strips of sheet metal were cut and bent into the A-shape according to the drawing. A hole for the 8 mm bolt was drilled at the tip of the bracket, and holes for 5 mm bolts were drilled in the legs.

The bracket was fitted inside the rim, and the positions for the bracket bolts were marked on the rim. The holes were drilled in the rim using a pillar drill. Now the hubcap bracket could be fastened at both legs to the rim. An 8 mm bolt was pushed through the hole at the tip of the bracket and tightened in place with a nyloc nut.

The hubcap was now ready to be fitted. The wheel was put back onto the undercarriage axle. The hubcap was pressed against the rim so that the bracket’s tip bolt protruded about half a centimetre through the hole in the centre of the hubcap. All that remained was to screw the nut onto the end of the bolt, and the Snoopy’s undercarriage wheel hubcap was complete. The hubcap will be painted bluish grey when the fuselage covering is painted.

Photos: Lassi Karivalo

Translation to English: Erja Reinikainen

Installing the Snoopy's (OH-XEA) roof window

Maanantai 22.12.2025 - Tuesday Club member

Suomeksi

There was a plexiglass roof window above the seat in the Snoopy’s cockpit. That window has not survived. From the existing photographs and the material list we know that the window was made from green acrylic sheet. The photos also show that the acrylic in the roof window had already cracked. Acrylic is, in fact, prone to cracking or splintering when it is sawn to shape. The cockpit roof window was attached with small bolts to the brackets welded onto the roof frame tubes. Two of these brackets are missing, having come off at some point.

Differing from the Snoopy’s original roof window, we decided to make the new roof window out of polycarbonate sheet, which is easier to work with. However, thin and transparent green polycarbonate sheet was not available. Therefore our approach is to make the roof window from 2 mm thick polycarbonate sheet and add a transparent green film to its surface.

We began constructing the roof window by making a cardboard template. We measured the size of the window and cut a piece of cardboard accordingly. We then fitted the cardboard into the roof window opening, trimming it to its final shape. Using this cardboard template, we purchased from Etra a piece cut from 2 mm thick polycarbonate sheet.

We fitted the polycarbonate sheet into place. There is something unusual about it, as the frame has mounting brackets for the roof window sheet on only three sides. There are no brackets on the cross tube beneath the front edge of the roof window. We have no information on how the window sheet was originally fastened at its front edge to the cockpit roof cross tube.

However, photographs taken of the Snoopy show that at this cross tube, the roof window and the windscreen meet. Presumably, at the cross tube, the rear edge of the windscreen rests on top of the front edge of the roof window. This way, the airflow passes over the roof window sheet and cannot enter the cockpit.

What kind of joint there was between the roof window and the windscreen, is not clear from the photographs taken of the Snoopy. The photos do show, however, that this joint is covered by some sort of trim strip. How it was fastened is unclear, as there are no indications of it on the cockpit roof frame tube. However, the connection between the front edge of the roof window and the rear edge of the windscreen will need to be resolved at the latest when we bend the windscreen, made from polycarbonate sheet, into shape and fix it into place.

We continued fitting the 2 mm thick window sheet into place so that the edges of the sheet lined up with the rows of mounting brackets. Next, the holes in the brackets were marked onto the plexi sheet by shining a light underneath it. This way, the bracket and the hole for the mounting screw were clearly reflected onto the surface of the plexi sheet and could be marked with a marker pen. Once all the holes were marked, holes for the mounting screws were drilled at the marked locations. In fact, these are small mounting bolts with nuts.

We wondered how well the 2 mm thick polycarbonate sheet would bend to match the curved profile of the roof window. We first fastened the sheet to the brackets at its rear edge. Then, the sides of the plexi sheet were fastened bracket by bracket. We were pleased to discover that the 2 mm thick polycarbonate sheet bent surprisingly well to match the shape of the cockpit roof.

It was noted that the left edge of the plexi sheet protruded about half a centimetre beyond the line of the frame tube. Obviously, the sheet had been fixed slightly further to the left than intended. So a line was drawn on the plexi sheet to indicate the excess, and the extra material was removed using a fine-toothed bandsaw. After this, the sheet was put back into place.

It was still necessary to solve how to proceed with the two missing mounting brackets in the cockpit roof structure. The solution chosen was to fasten two small perforated angle brackets at the positions where the brackets were missing from the cross tube of the roof. The positions of the holes in these brackets were then marked onto the sheet. Once the holes had been drilled, the two mounting bolts could be put in place.

The front edge of the sheet has not yet been fastened to the cross-frame tube beneath it, as the method of attachment has not yet been decided. For the time being, the front edge of the roof window sheet is held in place on the frame tube with small clamps.

The roof window plexi sheet for the Snoopy is now in place. Protective film still covers both sides of the sheet. These will be removed when the roof window is eventually fastened into place after the restoration of Ressu has been completed. Before that, a thin transparent green film must be found to be glued onto the surface of the roof window sheet.

Photos: Lassi Karivalo

Translation to English: Erja Reinikainen

Unfastening of the OH-XTM Super Chug propeller and fitting a new one

Sunnuntai 7.12.2025 - Tuesday Club member

Suomeksi

The propeller of the OH-XTM Super Chug (in Finnish Super Sytky), which was damaged in a landing accident and donated to Aviation Museum Society Finland, broke in the crash. A replacement in good condition is required. The wooden propeller on OH-XTM was manufactured in the United States and bears a manufacturing plaque reading “MARFA HEGY TEXAS.” The propeller is stamped with the dimensions 54x44, indicating its diameter and pitch. It is also stamped with the numbers 6-81, which presumably refer to the month and year of manufacture.

Fortunately, we were donated a suitable propeller for the OH-XTM Super Chug’s VW 1600 engine. Antti Laukkanen, restoration manager at the Finnish Aviation Museum, decided to part with a propeller he had for the benefit of our Super Chug’s engine. This propeller was manufactured by E. Pankkonen in the 1970s. Pankkonen produced propellers under official permit, including those for the Fournier RF-5 “Tuulia” aircraft. These were much needed in the 1970s: according to the 1975 damage summary in the Finnish Ilmailu (= Aviation) magazine, the Tuulia in Turku was already using its eleventh propeller in its history!

We were eager to test whether the bolt holes of the donated propeller would fit the propeller hub of the OH-XTM engine. For this reason, the original but damaged propeller, which was still attached to the Super Chug’s VW 1600 engine, needed to be removed.

The disassembly began with the propeller hub cover, i.e. the spinner. Once the numerous crosshead screws at the rear edge of the spinner were removed, the spinner could be pulled off with a bit of prying.

Now the broken propeller could be detached. The propeller hub bolts came loose easily, allowing both the bolts and the propeller's mounting flange to be removed. There was some speculation as to how tightly the propeller would still be stuck to the mating parts of the mounting bolts. However, after tapping the propeller lightly with a rubber mallet, it came off easily.

With the propeller removed, the mounting ring for the spinner’s screws underneath could also be taken off, leaving only the hub with the propeller mounting bolt mating sleeves (threaded inserts) attached. During the disassembly, all screws, bolts and washers were labelled and placed in a plastic bag to await the completion of the Super Chug’s restoration and the installation of the new propeller on the VW 1600 engine.

Once the broken propeller had been removed and the hub was free, the donated propeller was test-fitted to the Super Chug’s engine. The propeller bolt holes in the donated propeller matched perfectly with the threaded inserts in the hub. The new propeller’s holes were, however, slightly smaller in diameter than the mounting bolts. This means that when the propeller is eventually installed on the OH-XTM Super Chug’s engine, its bolt holes will need to be slightly enlarged.

Photos: Lassi Karivalo

Translation to English: Erja Reinikainen

Cleaning and painting the Snoopy?s Continental A 65 engine

Tiistai 2.12.2025

Suomeksi

Ressu, i.e. Snoopy (OH-XEA) was originally equipped with a Continental A 65 engine. However, the original engine has not survived. Nevertheless, we managed to obtain a similar type of engine, from a crashed aircraft, to install in the Snoopy. Although this engine is damaged and unfit for use, it suits our purposes. We are restoring the engine to look like an operational one and supplementing it with missing parts so that it can be mounted on Snoopy’s nose.

All parts still attached to the engine, except for the cylinders, were disassembled. We were unable to detach the cylinders as the pistons were completely seized inside them. The detached parts were cleaned using various methods, including the engine block and its cylinders. For the cylinders, we decided that to paint them properly, including the cooling fins, they would have to be thoroughly cleaned before painting. Therefore, we opted to take the Continental engine block, with the cylinders still attached, for glass bead blasting at Taximo Oy in Tattarisuo, Helsinki.

Photo: Juha Veijalainen

Before sending the engine to be glass bead blasted, it was plugged up to prevent the blasting media from getting inside the engine, even though this engine will never run again. The open intake and exhaust ports were covered with thin aluminium plates. A similar protective cover was made from thin aluminium for the opening left by the removed timing gear cover, to stop blasting material from entering. This was done by placing the removed timing cover on a sheet of aluminium, tracing its shape, and cutting out a piece to match, with holes drilled in the edges for fixing pins.

We mounted the Continental engine onto an engine stand so that it could be rotated easily, much like a spit roast. To install the timing gear cover, the engine had to be removed from the stand. This was done with an engine hoist. Once the protective cover was attached, the engine was returned to its stand. It was deliberately taken for blasting while still mounted, as this made it much easier to rotate during the cleaning process. Our Continental A 65 engine was now ready for glass bead blasting.

Photo: Reijo Siirtola

The engine was transported from Puusepäntie to Tattarisuo in a passenger car, where the engine and its stand could be loaded, pulling it in with a cargo strap. A week later, the engine was collected from blasting and, still on the stand, was taken to the Finnish Aviation Museum for painting the cylinders. This was because the museum has a spray-painting tent, which we don’t have at the Puusepäntie workshop. Black and white photographs of the Snoopy show that the engine’s cylinders and valve covers were painted black, while the block was left in aluminium. We followed this original approach as well.

Photo: Juha Veijalainen

Photo: Reijo Siirtola

Before painting the cylinders, the block was protected with plastic. The cylinders to be painted were brushed and washed with Sinol to remove any dust left from the blasting. The spark plugs were then removed, and the edges of the plug holes were greased with Vaseline, as they were to be left unpainted. The engine was then taken to the painting tent in the museum’s yard. The cylinders were spray-painted with semi-gloss black Isoguard Pansar paint. Surprisingly, a large amount of paint was required, as the cylinders and their cooling fins had a lot of surface area to cover. The cylinders and cooling fins were painted twice to ensure the spaces between the fins were thoroughly coated.

Photos: Reijo Siirtola

After painting, the Continental engine was transported by car back to the workshop in Puusepäntie. There, the engine block was wiped down with Sinol, after which a clear Isotrol varnish was brushed onto the block’s surface to protect the aluminium from oxidation. Now the Snoopy’s Continental A 65 engine block and cylinders were cleaned and painted. The transformation from the engine’s original condition was remarkable.

Photos: Lassi Karivalo, unless otherwise mentioned

Translation to English: Erja Reinikainen

The OH-XEA Snoopy fuselage covering

Lauantai 8.11.2025 - Tuesday Club member

Suomeksi

Before the Tuesday Club’s summer break, we had attached the covering fabrics on the Snoopy’s fuselage upper and lower surfaces and on both sides of the cockpit. We couldn’t have covered more at the time because we had run out of the covering fabric we used. However, we had time to start the tightening lacquering on the fuselage upper and lower covering.

After the beginning of the autumn season we found a solution for continuing the Snoopy’s fuselage covering, because a bolt of fabric was found at the Finnish Aviation Museum and we got the use of it. We made the standard tightening test with nitrocellulose lacquer by attaching the fabric to a test frame. The test was started with water tightening, advancing by stages to 25%, 50%, 75% to full 100 % lacquer. The result of our testing was that the fabric seemed to be suitable for continuing the Snoopy’s fuselage covering.

The covering of the Snoopy’s sides was started by making a cardboard template of the sides. According to them, pieces of fabric were cut off for the covering of the sides. The pieces of fabric, cut to form, were attached to the frame of the fuselage with contact glue. The fabric was first glued from its upper edge to the frame tube of the fuselage. After this the fabric was glued from its lower edge to the frame tube, stretching it from the hem at the same time. This way the fabric was made tentatively tight to wait for the water tightening and the subsequent tightening with nitrocellulose lacquer.

After the glue had dried at the seams, the pieces of fabric were water tightened, i.e. soaked with boiled water. After the fabric had dried, the tightening process with nitrocellulose lacquer was started. We began with 25% lacquer and now we have progressed to 50% and 75% lacquer. As the lacquer we used NC-Speed nitro lacquer, tinted with iron oxide. Simultaneously the tightening lacquering of the fuselage lower and upper surfaces, and the cockpit walls have been continued.

As the lacquering of the Snoopy’s sides proceeded, we noticed to our dismay that the tightening of the side fabric wasn’t even. The warp of the fabric had tightened better vertically than horizontally. The consequence being that a waviness was to be seen in the fabric. This new fabric wasn’t as well tightening as we had observed in the test we made. To be honest, we noticed that after 50% of lacquering, the waviness had diminished but not entirely vanished. It is unlikely that we will try to acquire a new better fabric to re-cover the Snoopy’s sides.

We still had to fabric the cockpit door and the floor of the cockpit and the bottom of the nose section. Cardboard templates were once again made of the above mentioned, and the right size pieces of fabric were cut off. The fabric was identical to the fabric used to the fuselage sides. We, however, believed the fabric will tighten enough in small areas. Again, we attached the fabric rims to the fuselage metal structure with contact glue.

The door with windows was covered up to the window opening, which will be cut open only after the fabric has been finally tightened with tightening lacquer, and the fabric glued to the door’s window frame. The cockpit door and the cockpit fabric and the fabric of the nose section lower part have now received two applications of 25% NC-Speed nitrocellulose lacquer, after the initial water tightening. The tightening of the covering fabric seems to be promising.

Photos: Lassi Karivalo

Translation to English: Matti Liuskallio

Restoration of the Snoopy's fuselage continues

Torstai 10.4.2025 - Tuesday Club member

Suomeksi

The fuselage of the OH-XEA “Snoopy” has been stored at the Finnish Aviation Museum since its restoration was put to hold in December. Now the fuselage has been transferred to the premises rented by the Aviation Museum Society at Puusepäntie in Tuusula, and it is possible to carry on with the restoration work. Although we couldn’t yet fully concentrate on the restoration projects, because the Tuesday Club’s workshop had yet to be fully refurbished. However, we were able to start the restoration work along with finishing the refurbishing of the workshop.

We carried on with restoring the Snoopy with attaching instruments in its empty instrument panel. The lacking instruments have now been installed. The missing instruments could be seen in a photograph of the Snoopy’s instrument panel from 1969. We are grateful to the people at Turku Flying Club, who rustled up most of the instruments in the panel. We also thank the Finnish Aviation Museum for providing us with the rest of the missing instruments.

Kuva: Esko Keskinen

In completing the instrument panel, the one instrument giving us the biggest problems was the Russian air speed indicator, because it lacked the mounting ring fastened on the instrument. Well, we managed to install the instrument with a clamp around it. We were able to fasten the instrument with four angle irons under the clamp.

Because we didn’t want to leave empty the opening at the centre of the lower part of the instrument panel, we stuck temporarily a digital thermometer there. That’s to say, we don’t know which instrument there was originally, because that instrument is lacking from the photo at our disposal. Furthermore we put two switches we bought from Motonet into the two empty holes in the instrument panel. They don’t resemble the earlier ones with longer stems in the Snoopy’s instrument panel, but we’ll let them stay there for the time being. Of course, we’ll be trying to find switches like the original ones to be installed into the instrument panel.

Kuva: Jouni Ripatti

The Snoopy’s metal fuselage frame was completed for covering at the end of 2024. So, we have started covering the fuselage frame with the vertical stabilizer, which is an integral part of the fuselage frame. We made at first a cardboard template of the stabilizer. Cotton fabric was spread over the template and a piece of fabric, a bit larger than the edges of the cardboard template, was cut off.

The fabric was cut to oversize with intention, to leave adjustment allowance, when cutting the fabric to a tight fit.
The cut fabric was laid tentatively on the vertical stabilizer so that the lapels were left outside the trailing edge. We spread NC-Speed nitrocellulose lacquer to the stabilizer’s leading edge and pressed the fabric tightly against it. This way we managed to glue the fabric to the stabilizer’s leading edge, allowing the lapels to be glued with lacquer to the trailing edge of the stabilizer.

All the more, we wanted to check the tightening properties of the fabric we were using. So we attached a piece of fabric with a stapler to a wooden framework and started tightening the fabric with nitrocellulose lacquer. After two layers of 25% lacquer, we spread a layer of 50% nitro lacquer. After applying these layers of lacquer, the fabric began to tighten in a way we’d hoped, i.e. shrink to resemble a drum top. The final tightness will be found out when we’ll get to using the 100% NC Speed nitrocellulose lacquer.

The Snoopy’s fuselage frame came to us without the cockpit plexiglass panes and the windscreen. The new plexiglass panes of the left-hand side of the cockpit and the right-hand side door pane were acquired and cut to form already towards the end of last year. They were made of 3 mm thick polycarbonate plexiglass. A cardboard template was made of the missing cockpit windscreen, and a plexiglass blank will be cut according to the template. The plexiglass sheet will be bent to the right shape by heating, so that both sides of the windscreen nestle tightly to the front sides of the cockpit. So far we haven’t tried this kind of plexiglass shaping by heating, but we are confident of making it a success.

Photos by Lassi Karivalo except if otherwise mentioned.

Translation to English by Matti Liuskallio.

Snoopy's fuselage and engine to Puusepäntie

Torstai 27.3.2025 - Tuesday Club member

Suomeksi

Equipping the Aviation Museum Society’s rented premises at Puusepäntie in Tuusula into the workshop for the Tuesday Club has advanced so well that we decided to move the fuselage and engine of the experimental aircraft Snoopy, stored at the Finnish Aviation Museum, to the new workspace.

This means that restoring the Snoopy will continue from the point where we left it at the end of last year. Bringing the Snoopy to Puusepäntie is a kind of milestone in taking the rented workspace into its proper use. Well, the equipping of the Puusepäntie workspace is still not quite finished, but we’ll get there while working on the Snoopy and other restoration projects.

Let it be reminded that restoration work at the Finnish Aviation Museum’s restoration workshop came to a close at the end of last year, because the restoration workshop was changed into a space supporting the oncoming move of the Finnish Aviation Museum. The Tuesday Club will participate these Museum operations and continue restoring museum worthy aircraft at the Aviation Museum Society’s rented workshop at Puusepäntie.

Kuva: Jouni Ripatti.

Kuvat: Reijo Siirtola.

On Tuesday, 25 March 2025 we gathered at the Museum to transport the Snoopy’s fuselage and engine to our new workshop. The Snoopy’s fuselage and engine, situated in a storage container, were pulled out of the container to the Museum yard. The fuselage was hoisted on to a trailer, where it was carefully fastened with cargo straps. A light tarpaulin was spread on the fuselage to protect it during the trip. The Snoopy’s engine, fastened in its mount could be loaded in a minivan.

Kuva: Jouni Ripatti.

Kuva: Reijo Siirtola.

When the loading was ready, we drove the ten or so km from the Museum to the Puusepäntie workshop. There the fuselage and engine were unloaded and pushed into their new home.

Kuva: Reijo Siirtola.

Kuva: Reino Myllymäki.

The Snoopy’s restoration will commence at the beginning of April, simultaneously with giving the workshop the finishing touches.

Translation to English by Matti Liuskallio.

The Snoopy got its horizontal stabilizer struts

Maanantai 27.1.2025 - Tuesday Club member

Suomeksi

The Snoopy horizontal stabilizer has on both sides a metal strut attached to the fuselage. The struts haven’t survived, so they had to be made. We scrutinized photos of the Snoopy. They showed that the struts have been of round metal tube. We found at the metal store of the Finnish Aviation Museum some 10 mm thick aluminium tube, suitable for making the struts.

Photo by Esko Keskinen.

For making the struts their lengths had to be determined. Therefore the Snoopy’s horizontal stabilizer was fastened to the fuselage. It is fastened to the fuselage with three 8 mm thick bolts. They haven’t survived either. So we bought such ones with nuts and washers. Before fastening the stabilizer, the holes for fastening the stabilizer on the fuselage were cleaned with a round file, after which the stabilizer was fastened to place.

Now the strut length from the bracket in the fuselage to the fastening bolt in the stabilizer could be measured. It turned out to be 60 cm.

Two 60,5 cm long pieces were cut off the aluminium tube. The ends of both the tubes were squeezed flat for drilling holes for the fastening bolts. At first the holes for the fastening bolts were drilled to one end of the strut, after which the struts were fastened to the brackets on the fuselage. The flat top end of the strut was placed in line with the fastening bolts in the stabilizer. We saw that the top end of the strut fitted exactly to the bolt.

We marked the place for the fastening bolt to the flat top ends of the struts with a felt pen and holes were drilled accordingly. After that both struts were fastened in place on the stabilizer. It was noticed that the stabilizer was horizontal and steady at its place. So the horizontal stabilizer had received its new struts.

The struts made of aluminium tube were unfastened to be painted. The struts were painted with blue grey Isotrol oil paint. At the same time the elevator operating rod, made of aluminium tube, was painted. After the paint had dried, the struts were once more put to place, after which the stabilizer was unfastened, waiting for the fuselage restoration to be ready.

Photos by Lassi Karivalo except if otherwise mentioned.

Translation to English by Matti Liuskallio.

Installing the control wires in the Snoopy's tail

Torstai 2.1.2025 - Tuesday Club member

Suomeksi

The experimental aircraft Snoopy, under restoration at The Tuesday Club, retains the wires from the rudder pedals to the rudder and tail wheel. Instead, the elevator wires had disappeared.

We examined the Snoopy’s fuselage to find out how the elevator wires had run. It transpired that the upper wire is attached to the top end of a rocking lever in the tail. Accordingly, the lower wire is attached to the lower end of the rocking lever. So, how to move the elevator? From the photos taken of the Snoopy we noticed a bar from the tail to the underside of the elevator. The other end of this metal bar has been attached to the lower end of the rocking lever, where there are holders both for the wire and the bar. As the wires tilt the rocking lever from side to side, the metal bar moves back and forth, making the elevator move up and down.

At the lower end of the control column the lower elevator wire runs through a pulley in the fuselage and on through a tube in the control column lower end winding around a pulley to the lower end of the control column. Accordingly, the elevator upper wire runs from the rocking lever through a pulley in the fuselage, straight to the lower end of the control column. This way the wire forms a connected wire loop that can be operated from the control column.

Before we started to install the elevator wires, we had to lathe the two missing pulleys in the fuselage that guide the movement of the wires. The bolt holes in the pulley holders were drilled clean, after which the pulleys were installed. Now we could start threading the wires to place.

The wires were tentatively fastened with loops with wire locks to the lower end of the control column and the rocking lever. After it was defined how tight the wires should be, the wire ends were equipped with metal rings or thimbles. The wire was tightened around the thimble and the end of the wire was locked at the stem of the thimble with two pressable wire locks made of aluminium. The thimble headed wires were finally threaded to the holder at the lower part of the control column and the locking loops attached to the rocker lever.

After the elevator wires had been fitted, we constructed the metal rod out of 20 mm metal tube, to move the elevator, and fastened it to lower end of the rocker lever. We further checked the working of the rod by attaching the horizontal stabilizer and elevator to the fuselage of the Snoopy. When we fastened the other end of the rod to the bracket on the lower surface of the elevator, it moved as planned, when pulling and pushing the control column.

A wire connects the rudder pedals both to the rudder and the tail wheel. The wire running towards the tail, forks halfway of the fuselage to wires going to the rudder and the tailwheel. The tailwheel turns simultaneously, when the rudder is turned by the pedals.

We fastened first the right- and left-hand side wire ends to the pedals. After that we attached the ends of the rudder wires, which forked halfway of the fuselage, to the brackets on the lower left-hand and right hand-side corners of the rudder. At the same time we noticed that in front of the rudder, there had been pulleys guiding the wires in the fuselage. All that was left was the holder for the pulleys.

The missing pulleys were lathed and attached in place. Thus the rudder wires had been installed.

It was time to install the tailwheel wires. The left-hand side wire had been linked to the tailwheel by a coiled spring. The right-hand side original wire lacked the coiled spring. When we thought about the problem, we found out that both the wires should have the coiled spring for the rudder to function properly.

We studied photos of the Snoopy. It transpired from them that both the rudder wires did have a coiled spring. Why it lacked from the right-hand wire, will remain a mystery.

We carried on pondering. If the tailwheel wires have coiled springs, they must have counter springs in the pedals. This way the wires between the pedals and the rudder could remain tight and the rudder movements transit to the rudder and tailwheel. Small metal rings were found in the fuselage and rudder pedals. So we bought suitable coiled springs and installed them to the rudder pedals.

We also bought coiled springs for both the tailwheel wires.  So we decided to renew the left-hand side tailwheel coiled spring, in order for both springs to be identical. Before installing the tailwheel wires, we had cleaned the pulleys for the tailwheel wires to be fastened to the tailwheel coiled spring.

At first the coiled springs on both sides were fastened to the brackets in the tailwheel. After this both the wires were attached to the coiled spring with a ring made to the end of the wire. The ring was locked with two wire locks that were pressed around the wire. We still installed, as had been in the original, a backup wire between the brackets and the ends of the wires. The backup wire was threaded through the coil spring. The wire ensures the function of the tailwheel if the coiled spring breaks loose or breaks. We added a turnbuckle to the left-hand side wire of the tailwheel to adjust the tightness.

Thus we had installed to working order all the Snoopy’s control wires in the tail section.
A different story will be the fitting of the aileron wires in the wings.

Photos by Lassi Karivalo.

Translation to English by Matti Liuskallio.

Painting the propeller of the Snoopy by its painting scheme

Perjantai 20.12.2024 - Tuesday Club member

Suomeksi

The damaged Hoffmann Rosenheim propeller, received as a donation, was primed after its repair with bluish-grey Isotrol oil paint. This paint suits for both priming and surface painting. After the priming, putty was still re-applied to some uneven spots, after which the propeller surfaces were thoroughly ground smooth with sandpaper. The grinding dust was wiped off with a rag moistened with Sinol / water solution (50% / 50%).

Now we proceeded to painting the propeller by the original painting scheme as in the Snoopy, documented in photographs of it. The tips of the blades were red, with a narrow white stripe in the bottom edge of the red. The front side of the blades was painted with the same bluish-grey paint as the whole aircraft. The back side of the blades had been painted matt black between the red tip of the blade and the propeller hub, to prevent glare.

Painting the propeller as in the Snoopy painting scheme was started, after grinding the primer, by covering it fully with bluish-grey Isotrol paint. The front side of the blades simultaneously received its final bluish-grey coat of paint. The paint job was done with a brush. Spray painting was considered, but Isotrol gives an extremely even, smooth, plastic-like surface even when applied with a brush.

Next were painted the red propeller tips. Red spray paint was bought, and used for it. The length of the red tip was estimated based on photos of the Snoopy. It was about 1/3 of the distance between the propeller hub and the tip. The tip part was separated with tape, and the rest of the propeller was protected with cardboard for the time of painting. At first, the front sides of the propeller blades were sprayed red. After the paint had dried, the back sides of the propeller blades were sprayed equally.

Because spray paint dries quickly, the back sides of the propeller blades could be painted matt black on the same day. That was also done by spraying it. Again, the length of the matt black area was defined by photos of the Snoopy. The matt black area reaches from the red tip to the edge of the propeller hub, where tape was applied for separating it. Now, both the tips of the propeller blades and the hub area were protected, and the back side surface of the blades was sprayed matt black.

What is still missing is the white stripe separating the bottom of the red areas from the bluish-grey and matt black areas of the blades. The paint job did not make it in time before the Christmas pause of the Tuesday Club, so the painting will be delayed until the spring of 2025.

The donated German Hoffmann Rosenheim propeller had thus acquired the external appearance of the propeller used in the Snoopy, except for the white stripe.

Photos by Lassi Karivalo.

Translation to English by Hannu Mononen.

New plexiglass windows for the Snoopy's cockpit

Tiistai 17.12.2024 - Tuesday Club member

Suomeksi

The experimental aircraft Snoopy (OH-XEA), under restoration in the Tuesday Club, has plexiglass windows on the doors of the left- and right-hand sides of the cockpit. They have been preserved, but turned dim, yellow, and scratched. Therefore, they will be replaced. The original ones are of polycarbonate plexiglass, to be used also in the new ones.

Photo by Esko Keskinen.

We decided to test assembling the original dim glasses in place, to find out how they were fastened, thinking about buying and assembling new plexiglasses. For attaching the glasses, there are threaded brackets in the fuselage frame of the cockpit, into which the plexiglasses are fastened with screws.

When the original plexiglasses were fitted in place it was noticed that the holes for attachment screws no longer matched everywhere with the holes in the brackets of the fuselage framework. The plexiglasses had somewhat changed their form and shrunk over time. Thus, in many places, new holes had to be drilled or existing holes had to be enlarged to match the plexiglass holes with those in the brackets of the fuselage framework.

When attaching the plexiglasses with screws into the brackets had started, it was observed that the threads in the brackets no more worked in all of them. Therefore, into all of the bracket holes for the plexiglass on the sides of the cockpit and the doors, new threads were made with a tap for 4 mm screws. These screws were purchased and then the old plexiglasses could be mounted into place. Now, the test-fitted old plexiglasses were detached, and marks matching with their attachment brackets were made onto them with a felt-tip pen, for drilling holes into the new plexiglasses. 

New plexiglasses were bought from an Etra shop, where they were cut ready into the shape of the old ones. The old plexiglasses had the thickness of a good millimeter only, and were thus rather flimsy. Therefore, we decided to buy a little bit stronger material and ended up with the thickness of 2 mm. The sawed edges of the new plexiglasses were ground smooth.

Holes were made into the new plexiglasses for attachment screws, according to the original ones. The old plexiglass was placed on top of the new one, and the spots for holes were marked with felt tip pen onto the new one. With a column drill, 4 mm holes were drilled. When screwing the plexiglasses in place was started, it was noticed that the 4 mm holes were slightly tight, and the plexiglass could not be pressed smoothly against the fuselage framework. The holes were widened, and thereafter the plexiglasses of the cockpit door and the left-hand side wall could well be pressed against the fuselage framework. The new plexiglass windows had been assembled. For the time being, the protective films on the plexiglass surfaces will be left in place.

The cockpit windscreen has also been plexiglass, but is has not been preserved. Thus, it must be made. It is a single pane, the same sheet of plexiglass in the front as well as the parts bent to the sides. The bent plexiglass has been attached to its brackets in the fuselage framework through the screw holes by its edge.

To make a new windscreen, we plan to proceed by first making a cardboard model of it. Accordingly, we will get a sheet of plexiglass that will be bent in shape for attachment. It will also be made of 2 mm polycarbonate, bent into the angular shape of the Snoopy’s windscreen by heating.

A large sheet of cardboard was cut and started to be formed into the place of the windscreen, cutting it smaller piece by piece, until it corresponded with the shape and size of the original windscreen visible in photos of the Snoopy. It was checked that the edges of the cardboard will settle in line with the windscreen attachment brackets of the fuselage. There are still adjustments to be made until, based on the spread-out cardboard template, a sheet of polycarbonate plexiglass of its shape will be purchased and bent into its final shape.

Photos by Lassi Karivalo except if otherwise mentioned.

Translation to English by Hannu Mononen.

Painting the Snoopy's rudder decals and taping them

Perjantai 13.12.2024 - Tuesday Club member

Suomeksi

Unlike the other control surfaces, Snoopy’s rudder is covered with fabric. The other surfaces are covered with plywood. The paint on the rudder fabric was badly crackled and also tatty. That’s why we had to cover the rudder again. The new covering and the tightening with lacquer have been dealt with in the blog of May 6.

After the tightening with lacquer (shrinking dope) the fabric surface of the rudder was painted with the blue greyish Isotrol -oil paint the same shade as the original. The painting was done with a hand brush, because the Isotrol paint leaves a very smooth surface when painted with a hand brush.

Before painting the paint was filtered through a funnel to eliminate any lumps. The surfaces were painted twice over, after which the surface of the covering fabric was even and semi glossy. It was time to paint the speed lines and symbols the rudder once had.

On each side of the rudder there are red speed lines cutting diagonally across the surface. In addition, on the left-hand side of the upper part of the rudder there was number 2, and on the right-hand side a profile of a bird with spread wings. Did Esko and Ari Hietanen have a raven in mind?

Both the bird profile and the number 2 were copied on transparent paper from the old fabric that was detached from the rudder. From the paper they were transferred on to black contact plastic and cut off with scissors. Originally the symbols had been of black contact plastic, i.e. they weren’t painted on the rudder fabric.

First the red speed lines were made on the recently painted rudder. They were made exactly according to the originals, or copied from the covering fabric detached from the rudder. The shape of the speed line was bordered on the surface of the rudder with masking tape. The bordered area was painted with red Isotrol- paint. It’s of the same shade as the original. When the speed line on the left-hand side had dried, a similar line was painted on the right-hand side of the rudder.

Now the previously copied symbols, the bird figure and the number 2 could be fastened into place, number 2 on the left hand-side of the rudder and the bird figure on the right-hand side. The rudder restoration was ready.

Photos by Lassi Karivalo.

Translation to English by Matti Liuskallio.

Painting of the repairs in the plywood cover of the Snoopy

Tiistai 10.12.2024 - Tuesday Club member

Suomeksi

After we had patched the holes in the plywood-covered wings, ailerons, horizontal stabilizer, and elevator, those patched spots were ready for painting.

We do not intend to paint all through the patched parts of the Snoopy, but the patches only. This is because in restoration we strive to preserve the original paint surface whenever it is possible. The painted surfaces of the Snoopy’s wings and tailplane still remain in excellent condition. That became evident when prior to fixing the damaged spots we cleaned the plywood surfaces from the dust and dirt that had accumulated during decades. The washed surfaces, most likely painted with Miranol-paint at the time, looked like newly painted.

The painted and repaired areas were re-painted with Isotrol oil paint that produces a paint surface similar to Miranol. It only required first defining the original blue-grey hue for toning the Isotrol paint. This created us a little problem.

Even though all the plywood-covered parts of the Snoopy had been painted simultaneously with the same blue-grey paint, those paint surfaces had become covered with patina or faded at a different pace during the decades. There were distinct differences of hue between painted parts of the Snoopy. Thus, the hue in the colour chart that matched for example the colour of the left wing, did not match with the elevator. We had to settle for a compromise in defining the hue, by choosing one that in average corresponded with the Snoopy’s patina-covered painted plywood surfaces. The formula for this hue became +CT101 3,2GR/0,5 l KAAVA, and the Isotrol paint was toned accordingly.

The paint job was done with a brush, Isotrol paint being brush friendly. The paint covers extremely well already at the first time, and it smoothens also extremely well when applied with a brush, forming an even, semi-glossy surface. After the paint has dried, the covered surfaces can still be polished with mineral spirits.

The paint job was done inside a painting tent or a tent-like cover beside the restoration workshop of the Finnish Aviation Museum. It can be warmed and has effective ventilation. Thus the patchwork of plywood surfaces on both wings, ailerons, horizontal stabilizer, and elevator received a beautiful blue-gray Isotrol coating in the painting tent.

After the painting, there was still some work to be done on the Snoopy’s left wing, because patching the plywood cover of the wing had destroyed some of the letters in the registration marking OH-XEA. The letters O and H had to be complemented. As the marking had been made on the wing using black contact plastic, we decided to do the same.

Black contact plastic was purchased. The lines were marked with sticky tape on the wing to define the location and size of the missing parts. Thereafter, the missing parts of the letters O and H were drawn on transparent rice paper to make a template for them. Placing the rice paper template on top of the black contact plastic, a carpet knife was used to cut through the rice paper the missing part of each letter. These letter parts were then precisely placed to complete the damaged O and H, which succeeded perfectly. Even by a close scrutiny, the seam between the original letter and its complementary part cannot be detected.

The restoration work of the plywood-covered wings, ailerons, horizontal stabilizer, and elevator has thus been completed.

Photos by Lassi Karivalo.

Translation to English by Hannu Mononen.

A propeller for the Snoopy's engine

Maanantai 25.11.2024 - Tuesday Club member

Suomeksi

The Aviation Museum Society’s donation, the OH-XEA Snoopy experimental aircraft, was without its Continental A 65 engine and the propeller. As far as we know, the engine and propeller had been given away, after the Snoopy’s flying days were over.

Photo by Esko Keskinen.

The problem of the missing Continental A 65 engine was solved when we were donated a damaged Continental engine of a plane that had crashed. It’s not airworthy, but it needn’t be, because the Snoopy won’t be restored to flying status. We’ll restore the engine looking complete and make the exhaust pipes, looking like those that were in the Snoopy’s Continental engine.

Photo by Juha Veijalainen.

We were also lucky about the missing propeller. We were donated a slightly damaged and struck off propeller, fitting the Continental A 65 engine. The wooden propeller is made by the German Hoffman Rosenheim works in 1986. One propeller tip is damaged. It’s both broken and has a dent in the leading edge.

The division between the six fastening bolts was exactly the same as in the propeller hub of the Continental A 65. The holes were, however, slightly smaller, so we drilled the holes with a column drilling machine to respond the to the fastening bolts of our Continental engine propeller hub. The compatibility was tested by fastening the propeller to the hub.

Because the propeller is mainly white, it doesn’t correspond to the Snoopy’s propeller in appearance. The Snoopy’s propeller tips were red. At the bottom of the red area there was a narrow white stripe. Otherwise the propeller frontside was blueish grey or the same colour as the aircraft itself. The backside of the propeller was, however, painted black between the white stripe and the hub.

We’ll repair and restore the propeller’s outer appearance like it was in the Snoopy. That’s why the markings and tapes were sanded off the surface of the donated propeller and anyway the propeller’s surface was rebuffed for the painting.

The crack in the other propeller tip and the dent in the leading edge had to be fixed before painting. We ended up fixing the tip crack with epoxy glue. So the crack was immersed in epoxy glue, after which it was pressed tight between two plastic plates with clamps. When the clamps were taken off after the glue had dried, the crack was well closed and the propeller tip was sanded smooth.

The dent in the propeller’s brass leading edge was first tried to straighten and then file smoother, but the metal turned out to be too hard to shape. So we decided to spackle the dent full with Lightweight Epoxy Filler. When the filler had been spread over the dent, the dent was covered with a plastic mould, shaped similar to the profile of the propeller leading edge. The mould was pressed with clamps to the leading edge.

After the filler had dried, the mould was taken off. It was noticed then that part of the filler hadn’t adhered properly to the dented area, but had come off with the mould. So we spackled the unsatisfactory part again, after which the leading edge dent became universally smooth. The propeller repairs had been accomplished and the priming of the propeller could be started.

Before starting the priming, the surfaces of the propeller were once more buffed lightly with sanding paper. The buffing dust was first wiped off with a dry cloth and finally with soft cloth immersed in a 50%/50% mixture of Sinol /water. The priming was done with a paint brush. As the paint, we had the same blue greyish Isotrol oil-based paint, that we used in painting the Snoopy’s wings, horizontal stabilizer and elevator plywood patches. The shade is the same blue greyish colour that was used on the Snoopy’s original surfaces. The priming will clearly show if the propeller surface will need any additional spackling. After the paint had dried out it was noticed that no more additional spackling or sanding was needed before the painting of the propeller to the scheme used in the Snoopys propeller.

Photos by Lassi Karivalo except if otherwise mentioned.

Translation to English by Matti Liuskallio.

Refurbishing the Snoopy pilot's seat

Torstai 7.11.2024 - Tuesday Club member

Suomeksi

The pilot’s seat of the Snoopy experimental aircraft, built by the brothers Hietanen from Turku, at the end of the 1960s, was moulded along the times. In the first version, the seat frame had a curved back support and a back rest of plywood, covered with fabric. Later the back rest became rectangular with an inset for the pilot’s parachute. The material of the back rest was changed at the same time from plywood to aluminium. With the inset in the back rest, the distance between the pilot and the control column could be increased, because the Snoopy’s seat isn’t adjustable. The parachute backpack worked as a padding for the pilot’s back.

Photo by Esko Keskinen.

The seat of the Snoopy, a donation to the Finnish Aviation Museum a few years back, consists of the back plate, side plates the shaped bottom plate and the case at the rear of the back rest. These parts have been riveted with pop-rivets to the steel tubes of the seat frame. A plywood plate, with a canvas-covered padding, attached with screws to the cockpit frame, forms the seat.

After tens of years in storage the Snoopy’s seat steel tube frame was rusty, like the fuselage frame, the aluminium parts of the seat were dirty and oxidized grey. The plywood seat plate with its padding had totally vanished.

To restore the seat, we started by detaching the aluminium parts fastened to the seat frame. They were detached by drilling away the pop-rivets that had fastened the aluminium parts to the frame.

After that we disassembled the seat frame of tubular structure, to be refurbished. We had our work cut out for us in doing that. We had to use a jack and a plastic mallet, before we were able to detach the frame parts from each other, because they were joined together with rust.

After separating the frame tubes, they were cleaned from rust to be painted in their original appearance. We did the cleaning by hand, using sandpaper of various grits and abrasive pads. We also did the same to clean the Snoopy’s fuselage frame tubes.

Because we’ll use Isotrol-lacquer to prime the seat frame, the tubes need not be sanded into clean metal. It suffices that the surface rust has been removed and that the surface of tubes feels smooth to touch. An Isotrol paint of the original shade will be painted on the Isotrol primer.

The dirty aluminium parts of the seat were cleaned with Fairy Power Spray agent. The Power Spray is a very efficient detergent for dirt and grease. You spray the agent on the surface of the part to be cleaned and leave it work for a few minutes.

After that the parts will be dried with a cloth or rinsed with water. In doing so we had the aluminium seat parts looking quite different, compared to when we detached them from the seat frame. The aluminium parts will still be buffed out before fastening them back to the restored and refitted seat frame.

Photos by Lassi Karivalo except if otherwise mentioned.

Translation by Matti Liuskallio.

Cleaning the parts of the Snoopy?s Continental engine

Perjantai 1.11.2024 - Tuesday Club member

Suomeksi

As soon as parts had been detached from the Continental A 65 engine that we had received for the Snoopy (OH-XEA), originating from a plane destroyed in an accident, they were cleaned. Besides being physically damaged, the engine had also burnt. Unfortunately, many of its devices had been destroyed useless, so the missing parts also had to be searched for.

Photo by Erkki Rossi.

Small metal parts with little or no damage were cleaned from rust by bathing them 24 hours in 33 % solution of phosphoric acid. For example, the propeller hub, detached from the engine and dismantled into its parts, was all immersed into phosphoric acid.

When the acid starts working, foam will be forming on its surface. After a day and night, those propeller hub parts were taken out and carefully dried with fabric. As a result, the parts are rust-free, with dark grey clean surface. Even as such, the parts are fully usable.

However, we decided to blow the propeller hub parts with glass bead blasting to bright metal, to make them appear as brand new. One might ask, why not blast them straight away as rusty. We chose this approach to avoid contaminating of the glass blast media with rust enriching into it.

For aluminum engine parts with dirty surface, we chose another procedure. Aluminum parts that were dirty or blackened after burning, such as magnetos, were first cleaned of dirt and thereafter their surfaces glass bead blasted. Before the blasting, holes in the magnetos were plugged with wooden plugs to prevent the blast media from penetrating into the magneto. With the blasting, the magnetos got clean surfaces. Finally, the clean surfaces were treated with a solution of Sinol and water to prevent the oxidization of the surface.

Oily and dirty parts were initially washed in a basin dedicated to cleaning engine parts, with a handy brush that feeds washing liquid through a hose.

The washed parts were dried with pressurized air, aluminum parts then possibly treated with glass bead blasting and Sinol-water solution. This method was chosen e.g. for the aluminium distributor head cover.

Photos by Lassi Karivalo except if otherwise mentioned.

Translation by Hannu Mononen.

Preliminary steps for covering the Ressu (Snoopy) fuselage frame

Sunnuntai 27.10.2024 - Tuesday Club member

Suomeksi

The fuselage of the Snoopy experimental aircraft (OH-XEA) was covered with fabric. When Aviation Museum Society Finland received the Snoopy two years ago, the fuselage was totally stripped of covering fabric. Therefore, the fuselage will be covered at the Tuesday Club as it originally was. Luckily we have some good photographs of the Snoopy at our disposal to guide us with the covering. So to work.

The whole fuselage frame of steel tube has been cleaned of rust during the autumn, given a layer of lacquer and finally painted with red Isotrol- paint. These jobs have been necessary for starting the work on the fuselage frame. These include the installing of the long wooden battens along the sides and upper surfaces of the fuselage frame and the partial covering of the fuselage frame steel tubes with fabric strip.

Metal brackets with 10 mm slots have been welded to the structure of both sides and the upper surface. Thin wooden battens have been fastened to these brackets along the whole of the rear fuselage. The purpose of the battens is to keep the covering canvas separated from the fuselage frame trusswork. Otherwise the metal would start to “eat” into the canvas, especially when rusting.

In order to prevent direct contact between the canvas and the longitudinal steel tubes at the upper and lower corners of the fuselage frame, cloth strip had been tied around the tubes. There were still remains of these strips left in the tail and vertical stabilizer of the Snoopy.

Next we started making the long protecting wooden battens. We found suitable material to make the battens at the restoration workshop’s woodware storage at the Finnish Aviation Museum. The battens were cut to measure and shaped to fit the brackets. At fitting the battens the brackets were squeezed tight to them. The batten was locked into place with small nails. Finally the battens that were fastened to the brackets, were protected with nitrocellulose lacquer.

Along with making the battens, we started covering the steel tubes of the fuselage frame with 20 mm wide cotton strip or tape. We bought that from Eurokangas. When the shop assistant queried what we needed it for, we said that it was used for covering a museum aircraft. The assistant was surprised but interested, so we briefed her in more detail about the purpose of the fabric strip. We must have been the first customer of this sort.

The ribbon was wound around the fuselage tubes to form a solid surface of fabric around the tubes. We wound the fabric strip to overlap the edge by about 5 mm. The stripping thus became solid, without any metal surface being visible. On the lower surface of the fuselage, without the wooden batten, we wound the strip on the lower part trusswork as well.

All the strip-covered surfaces were finally treated with nitrocellulose lacquer, which simultaneously glues the strip onto the tubes and later functions as an adhesive surface for the canvas covering. The covering canvas is tightened with that very same nitrocellulose lacquer.

Photos by Lassi Karivalo.

Translation by Matti Liuskallio.

The surface treatment of Snoopy?s fuselage framework

Perjantai 25.10.2024 - Tuesday Club member

Suomeksi

The fuselage framework of the experimental aircraft OH-XEA “Snoopy”, currently being restored  by the Tuesday Club of Aviation Museum Society Finland, was without its fabric covering when the Society received its ownership. When and why the fabric covering had been stripped off, is not known. Anyway, Snoopy had been stored without its covering for a long time, as its fuselage framework, welded of 13 mm steel tube, was in such thick rust.

The first stage of restoring the fuselage framework was to clean it from rust. Cleaning the steel tubes until clear metal appears is however unnecessary, as removing the superficial rust will suffice. When the tube surface feels very smooth to your fingers, it is clean enough. For the purpose, we used sandpapers of various grades as well as scrubber sponge. The grinding dust was wiped away carefully with rags of fabric and solution mixed of Sinol spirits and water.

Not grinding the fuselage framework until clear metal shows is because for priming the tubes for their surface paint, we use the clear Isotrol lacquer (Klarlack Grund). This lacquer penetrates through possible rust to the surface of the tube, stopping the rusting process. The surface can then be painted directly on the lacquer.

After the whole fuselage framework was cleaned from surface rust, we then treated it by a thin coat of Isotrol, covering fully the steel tubes and other metal parts and giving the tubes a nice shiny surface.

After the lacquer had dried, the fuselage framework was painted with Isoqaurd Panzer, an alkyd oil paint for metal. Originally in the 1960’s, the fuselage framework had been painted with red Ferrex anti-rust paint, still visible as residues in the tubes. Simulating the red Ferrex, the Isoquard paint was tuned to the same tone of red. An exception was the landing gear that was painted with black Isoquard, according to its original black paint.

The fuselage framework surface treatment is now done.  The restoration work of Snoopy’s fuselage will next proceed with the cockpit, as well as measures priming the fabric covering of the fuselage.

Photos by Lassi Karivalo.

Translation by Hannu Mononen.

Making the engine cowlings for the Snoopy started with cardboard templates

Maanantai 30.9.2024 - Tuesday Club member

Suomeksi

OH-XEA Ressu (Snoopy) experimental aircraft from the 1960s that we are restoring, was equipped with a Continental A 65 engine. To replace the Snoopy’s lost engine we received, as a donation, a similar engine. The engine cowlings have vanished during the decades as well. So they’ll have to be made anew.

Photo by Esko Keskinen.

From the photographs we have at our disposal the size and form of the cowlings come out very well. The cowling is two partite. The larger, upper cowling, covers the engine from above and the smaller one covers the front part of the engine. The cowlings have been made of sheet aluminium, so that’s what we’ll be using too, utilizing 1 mm thick aluminium sheet. The fact that the original cowling rack fastened to the engine, has survived, will facilitate the making of the cowlings.

The constructing of the cowlings was started by cleaning the rusty cowling rack and painting it with black Isotrol paint. Black, because the original black paint was still faintly to be seen. The freshly painted rack was fastened to the Continental engine donated to us. The first phase to make the cowlings proper, was to make patterns or templates out of cardboard to fit above the rack. According to the cardboard templates aluminium blanks will be cut to be moulded to their final form.

Making the templates was started with the upper cowling. The template was made out two pieces of cardboard cut from a roll. First the tentatively cut left-hand side was fastened to the pegs in the protective rack. After that the same procedure was repeated with the right-hand piece of the template, after which the left and right-hand halves of the template were taped together. The united template of the cowling was modified by cutting and taping extra pieces to reach the final shape of the Snoopy’s cowling.

At this stage the making of the cowling template, covering the front end of the engine, was commenced. A piece of cardboard cut from the roll was bent against the front of the engine. The piece was gradually cut to form and the cardboard was attached to the pegs in the rack. By cutting suitable extra pieces of cardboard to the front cowling it was united with the upper cowling.

Thus, like a patchwork quilt, the cardboard template was built around the Snoopy’s Continental engine prior to making the aluminium cowling. The next stage will be to transform the shape of the cardboard template into aluminium sheets.

Photos by Lassi Karivalo except if otherwise mentioned.

Translation by Matti Liuskallio.

Continental A 65-8 engine for Ressu "Snoopy"

Sunnuntai 29.9.2024 - Tuesday Club member

Suomeksi

The OH-XEA “ Snoopy” experimental aircraft, built by the Hietanen brothers from Turku in the 1960s, now under restoration at the Tuesday Club, had a Continental A 65 engine. Before the Snoopy it was in the Piper Cub aircraft of the Turku Flying Club. The engine on the Snoopy hasn’t survived, and there is no knowledge about its fate. So we started to ask around whether a surplus engine was to be found somewhere. We could do with quite a dilapidated engine, since we weren’t restoring the Snoopy to an airworthy condition.

Photo by Esko Keskinen (1969).

Our query was successful, as we were offered the Continental A 65-8 engine of the PIK-11 “Tumppu” (OH-YMD) single-seat sport aircraft that had crashed in Mikkeli on 7 August 1999. The engine was damaged and burned in the accident. However, it could be refurbished to look externally intact, to be attached to the nose of Snoopy.

The miserable condition of the engine had been worsened by its exposure of several years to the mercy of the weather, thus having heavily rusted through. To start he refurbishment of this engine in the Tuesday Club, we fetched it from Tampere in the boot of a Skoda Octavia.  

Our purpose is neither to repair the Continental engine into working condition nor to restore the airworthiness of Snoopy. To refurbish the engine, we will dismantle it to pieces as fully as possible, then after cleaning and fixing those, the engine will be re-assembled and attached to the nose of Snoopy.

All parts of this damaged Continental are not remaining, as some of them were destroyed in the crash. However, we hope to find or to get substitute parts for the missing ones later on. We also welcome any parts rejected in repairing and servicing Continental engines.

Dismantling of the engine was started outdoors at the Finnish Aviation Museum by detaching the badly damaged engine mount and the lower oil sump, which were still attached to the engine. At the hub of the propeller, the burnt propeller stem remained. After the nuts of the hub bolts were loosened, the propeller torso could be detached.

Next the remaining left-hand side exhaust pipe, spark plugs, both magnetos attached to the timing gear cover, the cover itself and the sprockets under it were removed. The lid of the oil pump under the timing gear cover was opened and the pump sprockets were taken out to be cleaned.

Photo by Esko Rossi.

Dismantling the engine was continued at the Museum’s restoration shop. The engine was fastened to a trestle, where the engine could be turned around its longitudinal axis, like in a barbeque. This greatly helped the handling of the engine. Now we detached the valve rods of the rocker arms and thereafter the rocker axles, after which the rocker arms came off the cylinder head. It became clear that the valves didn’t budge an inch. We tried to make them move and loosen them by dissolving with antirust agents.

Also the propeller hub was stuck firmly to the crankshaft. To dislodge the hub for cleaning, we applied various antirust and lubricant agents, but the propeller hub just wouldn’t budge. We gave some time for the antirust agent to work and finally managed to get the propeller hub out with a puller.

Only the cylinders remained in the engine block. We wanted to get them unfastened, too, to facilitate blasting their surfaces clean when separated. We were increasingly worried whether the pistons inside were rusted too tightly onto the walls for the cylinders to be taken loose. Well, we can at least give them a go, as they say, and that’s what we decided to do.

We turned the nuts on the mounting pins open and tried if the pistons would budge. No go. We then poured white spirit into the cylinders through the plug holes, to see if it would squeeze between the pistons and cylinder walls, and mobilize the stuck pistons enough to detach the cylinders. So far, we haven’t succeeded in this, “but we shall never surrender” to quote Sir Winston Churchill.

Photos by Lassi Karivalo except if otherwise mentioned.

Translation by Matti Liuskallio.