The Building of My Tailwind
Continued
I had a chat with him, mentioned I was ready to cover and I would take him up on his offer. He said, "When you are ready, call me on my 1-800 number every morning and I will walk you through what you want to do that day." Some days I called him four times and it was like having an expert right with me.
The Poly Fiber Process is easy to use, even for someone who has not done it before.
I put this in the category of, even my wife could do this.
By the way, when covering be sure to start with the vertical stabilizer.
The instrument panel and radio panel are 1/8 inch aluminum and the panel on the right which holds the fuses is .032 aluminum. A friend of mine had punches for the instrument holes so he punched them and also cut out the panel for the radios. The instrument panel is shock mounted, the others panels are not. There is a 3/8 x .035, 4130 angle welded in place to give the shape for the top and to fasten the shock mounts. The bottom has 1/2 x .035 tube running from side to side with a 1 inch x .035 strap welded along it to attach the bottom of the panel. I painted the panels with a spray bomb and could not believe how well they came out. Most people seem to like the panel with what I have in it. I have enough stuff to go cloud busting which I like doing now and then. I have had a few people ask me what do I want all that stuff for. My only comment is, "If you don't know how to use it, you don't need it."
The Poly Fiber Process is easy to use, even for someone who has not done it before.
I put this in the category of, even my wife could do this.
By the way, when covering be sure to start with the vertical stabilizer.
The instrument panel and radio panel are 1/8 inch aluminum and the panel on the right which holds the fuses is .032 aluminum. A friend of mine had punches for the instrument holes so he punched them and also cut out the panel for the radios. The instrument panel is shock mounted, the others panels are not. There is a 3/8 x .035, 4130 angle welded in place to give the shape for the top and to fasten the shock mounts. The bottom has 1/2 x .035 tube running from side to side with a 1 inch x .035 strap welded along it to attach the bottom of the panel. I painted the panels with a spray bomb and could not believe how well they came out. Most people seem to like the panel with what I have in it. I have enough stuff to go cloud busting which I like doing now and then. I have had a few people ask me what do I want all that stuff for. My only comment is, "If you don't know how to use it, you don't need it."
I used 3/16 Lexan for the windscreen and it runs all the way back behind the head.
The three pieces it attaches to are 1/2 x .049 square aluminum. To bend these to fit and all other tubes I needed bent, I used the Y in my bending tree in front of the garage. The Fica tree was only too happy to help.
Into the 1/2 x .049 aluminum pieces I drilled and fastened rivnuts, then used flush screws to hold on the windscreen. All other windows are 1/8 Lexan. The back windows are held in with 3M double sided tape, the tape that holds trim on the sides of cars. There are no other fasteners.
Looking over my photos I realize I had the airframe completed, but not with all the details, when I started the wings. I built the wings while waiting for my welder to come and do all the little welding jobs that needed to be done. After the wings were completed he still had not finished everything, even though he came every weekend and worked hard.
I must say this - I love my wings because they allowed a lot of important changes to be made. The big 15 foot table came into play again. I could build the wings on one end and still have a work space on the other.
The three pieces it attaches to are 1/2 x .049 square aluminum. To bend these to fit and all other tubes I needed bent, I used the Y in my bending tree in front of the garage. The Fica tree was only too happy to help.
Into the 1/2 x .049 aluminum pieces I drilled and fastened rivnuts, then used flush screws to hold on the windscreen. All other windows are 1/8 Lexan. The back windows are held in with 3M double sided tape, the tape that holds trim on the sides of cars. There are no other fasteners.
Looking over my photos I realize I had the airframe completed, but not with all the details, when I started the wings. I built the wings while waiting for my welder to come and do all the little welding jobs that needed to be done. After the wings were completed he still had not finished everything, even though he came every weekend and worked hard.
I must say this - I love my wings because they allowed a lot of important changes to be made. The big 15 foot table came into play again. I could build the wings on one end and still have a work space on the other.
You start this project by making wooden form blocks for the ribs. You have to make two form blocks for front ribs and two form blocks for the long back ribs. You also have to cut out a back plate of wood that is just 1/8 inch smaller all around, then the four form blocks. These two sets of blocks and back plates are to make two different, front and back ribs that have the flange going opposite ways. With me so far?
There is a full size shape of the ribs on the plans and they are the exact shape of a Tailwind rib. Transfer the shape to some wood and trim out these blocks. Be careful to keep the exact shape.
There is a full size shape of the ribs on the plans and they are the exact shape of a Tailwind rib. Transfer the shape to some wood and trim out these blocks. Be careful to keep the exact shape.
Now that you have the blocks you will want to make a right and left rib, meaning opposite flanges.
To do this you stand the blocks on edge horizontally and together. Now looking at one end of these blocks you file a 3/8 inch radius the length of the blocks but only on the inside edges where the two blocks touch. OK. On the other side of these blocks on the outer corners opposite the 3/8 radius, draw two lines down the side first 3/16 and second 3/8 of an inch, full length. Now you file from the 3/8 radius, but not cutting into the radius, down to the first line. Make sure these filed down pieces are going in opposite directions on the two blocks. When you bend aluminum over these form blocks these filed down angles on the blocks allow for spring back of the flange. At this point if you bent aluminum over these blocks it would go all wonkie and not lie down right. So to fix this problem you file flutes into the wood where you use a dowel to force the aluminum down into the groove. But first you file these flutes into the wood 1 1/2 inches apart using a big round file.
To do this you stand the blocks on edge horizontally and together. Now looking at one end of these blocks you file a 3/8 inch radius the length of the blocks but only on the inside edges where the two blocks touch. OK. On the other side of these blocks on the outer corners opposite the 3/8 radius, draw two lines down the side first 3/16 and second 3/8 of an inch, full length. Now you file from the 3/8 radius, but not cutting into the radius, down to the first line. Make sure these filed down pieces are going in opposite directions on the two blocks. When you bend aluminum over these form blocks these filed down angles on the blocks allow for spring back of the flange. At this point if you bent aluminum over these blocks it would go all wonkie and not lie down right. So to fix this problem you file flutes into the wood where you use a dowel to force the aluminum down into the groove. But first you file these flutes into the wood 1 1/2 inches apart using a big round file.
They should be filed down to the second line you put on the block and only up to about 1/4 inch from the top, being careful not to cut into the 3/8 inch radius. The flute closest to the pointy end should be 2 inches from the tip. Now how does that look? Not bad! This is easy.
You now have the tops of the ribs finished with the flanges going in opposite directions. I hope. Well, turn them upside down and do the bottoms the same way. You will be finished in no time. It is important to make these right as you will see when you start banging out ribs. Next you should take one of these blocks and trace it on scrap aluminum leaving more than 3/4 inches all around, Draw a line the shape of the block at the 3/4 inch line and trim out this piece nice and neat because this will be your pattern for your rib blanks. You now have a piece 3/4 inches larger than the form block all around. The 3/4 inch is the flange when bent over. But wait; you still have to trim the front a little because it has too much metal to bend over for such a sharp curve. You do this by drawing a line around the tip 1/4 inch out instead of 3/4 inch. This line will come back from the tip 1 1/4 inches top and bottom and curve up to the 3/4 inch line and blend into it with a nice curve. Trim the excess piece of aluminum off, then sand the edges and Bob's your uncle. ( An English saying.) Where the ends of the ribs bend around vertically, in the corner where the horizontal edge and vertical edge meet, drill a 5/16 inch hole and snip out the corner. This is so it won't crack when you bend it.
You now have the tops of the ribs finished with the flanges going in opposite directions. I hope. Well, turn them upside down and do the bottoms the same way. You will be finished in no time. It is important to make these right as you will see when you start banging out ribs. Next you should take one of these blocks and trace it on scrap aluminum leaving more than 3/4 inches all around, Draw a line the shape of the block at the 3/4 inch line and trim out this piece nice and neat because this will be your pattern for your rib blanks. You now have a piece 3/4 inches larger than the form block all around. The 3/4 inch is the flange when bent over. But wait; you still have to trim the front a little because it has too much metal to bend over for such a sharp curve. You do this by drawing a line around the tip 1/4 inch out instead of 3/4 inch. This line will come back from the tip 1 1/4 inches top and bottom and curve up to the 3/4 inch line and blend into it with a nice curve. Trim the excess piece of aluminum off, then sand the edges and Bob's your uncle. ( An English saying.) Where the ends of the ribs bend around vertically, in the corner where the horizontal edge and vertical edge meet, drill a 5/16 inch hole and snip out the corner. This is so it won't crack when you bend it.
Go to it; cut all the rib blanks out, file and sand up the edges so there are no nicks to start a crack. This takes more time than banging out a ribs.
All the ribs are .025, 2024 T3 aluminum except for the two ribs that are on each end of the fuel tank. They are .032, 2024 T3 aluminum. Form these four ribs last because you will want to file down the form block a little more for the flange to bend a bit further so the spring back will be the same as the .025 ribs.
Whew, I am getting writer's cramp, but we are moving right along.
You are ready to make ribs now and this is the fun part because it looks like you have accomplished something.
Take a form block and place the back up block over it so it is centered; then drill two 3/16 inch holes about 3 inches from each end. It really does not matter where; it's just to hold everything in line. Place a rib blank centered between them and drill the hole in the blank so the three line up; then place a nail in each hole.
Put this in a vise and now you are ready to bang away.
All the ribs are .025, 2024 T3 aluminum except for the two ribs that are on each end of the fuel tank. They are .032, 2024 T3 aluminum. Form these four ribs last because you will want to file down the form block a little more for the flange to bend a bit further so the spring back will be the same as the .025 ribs.
Whew, I am getting writer's cramp, but we are moving right along.
You are ready to make ribs now and this is the fun part because it looks like you have accomplished something.
Take a form block and place the back up block over it so it is centered; then drill two 3/16 inch holes about 3 inches from each end. It really does not matter where; it's just to hold everything in line. Place a rib blank centered between them and drill the hole in the blank so the three line up; then place a nail in each hole.
Put this in a vise and now you are ready to bang away.
You have to have a rubber mallet, a must!
Start by tapping the aluminum over the form block, not the backup wood. At first you are not sure about this working and then it starts to take a little shape. Wow!
Once you have it banged down and it's all wonkie, take the dowel and lay it on the flange above the flute.
Bang the dowel with the mallet hard and force the aluminum into the flute. Neat eh? It takes the shape of a rib. Can't wait to turn it over and do the other side.
Soon you come to the little tip. It needs a little work tapping the metal around it. It goes wonkie but don't worry, play with it. When you get it off the block you can tweak it with pliers, trim a little off and do some filing. It only needs a bit of curved flange to give it strength.
Now you have formed a rib and you know it is a pretty good rib if you have to pry it off the form block.
Start by tapping the aluminum over the form block, not the backup wood. At first you are not sure about this working and then it starts to take a little shape. Wow!
Once you have it banged down and it's all wonkie, take the dowel and lay it on the flange above the flute.
Bang the dowel with the mallet hard and force the aluminum into the flute. Neat eh? It takes the shape of a rib. Can't wait to turn it over and do the other side.
Soon you come to the little tip. It needs a little work tapping the metal around it. It goes wonkie but don't worry, play with it. When you get it off the block you can tweak it with pliers, trim a little off and do some filing. It only needs a bit of curved flange to give it strength.
Now you have formed a rib and you know it is a pretty good rib if you have to pry it off the form block.
Get to it and bang them all out but keep in mind equal number of flanges, right and left. One thing I should mention, it is imperative that they are all the same lengths and that goes for right and left flanges.
There are a few other things to know about building the ribs like joggling and the inside rib being shorter but they are well described on the plans and easy to do. The hard part is finished.
The spars were made on top of two recycling crates that sat on top at the edge of my table. They were easy to build this way after I got a few holes in them to hold it all together with clecos. Oh yes, you need a lot of Clecos, number 30 and number 40, 40 being the smallest.
With every hole in the wings I started with a number 41 drill and that hole would take a number 40 cleco. When everything was lined up and I was ready to rivet I would re-drill with a number 30 drill and put in a number 30 Cleco; also, this hole would take an 1/8 inch rivet. This way if the holes were not quite lined up you could adjust a little.
Every rivet inside the wings is a solid rivet and every rivet on the outside is a flush 1/8 inch Cherry Max.
There are a few other things to know about building the ribs like joggling and the inside rib being shorter but they are well described on the plans and easy to do. The hard part is finished.
The spars were made on top of two recycling crates that sat on top at the edge of my table. They were easy to build this way after I got a few holes in them to hold it all together with clecos. Oh yes, you need a lot of Clecos, number 30 and number 40, 40 being the smallest.
With every hole in the wings I started with a number 41 drill and that hole would take a number 40 cleco. When everything was lined up and I was ready to rivet I would re-drill with a number 30 drill and put in a number 30 Cleco; also, this hole would take an 1/8 inch rivet. This way if the holes were not quite lined up you could adjust a little.
Every rivet inside the wings is a solid rivet and every rivet on the outside is a flush 1/8 inch Cherry Max.
Remember not worrying about leveling the table? Well, this is why. I assembled the ribs to the spars and also skinned the wings while they were sitting on four one gallon paint cans. The spars sat on the cans at their ends and only needed a small bit of shimming to one corner to make it all level.
Riveting all the ribs to the spars is fun because you are assembling something and it looks like your accomplishing something. You are but where do you put these big things?
Next it was time to bend the wing skins. I phoned my friend Tom Griffith to see if he would come over and add a little input. The idea was to bend them on the table, that is what Callbie said to do but you know some of the old timers make it sound so simple or they miss telling you one little key item and you flounder around forever like in a bad dream, saying to yourself, "Why, oh why did I ever start this thing."
Riveting all the ribs to the spars is fun because you are assembling something and it looks like your accomplishing something. You are but where do you put these big things?
Next it was time to bend the wing skins. I phoned my friend Tom Griffith to see if he would come over and add a little input. The idea was to bend them on the table, that is what Callbie said to do but you know some of the old timers make it sound so simple or they miss telling you one little key item and you flounder around forever like in a bad dream, saying to yourself, "Why, oh why did I ever start this thing."
NOT SO!
Tom and I clamped a folded over skin to the table. I got up on the table with a flat board and forced the skin down so the leading edge would bend.
Tom was at the edge of the table and when he thought it was bent enough I would let up and he would try a rib in the fold. We kept doing this till it took the shape of the leading edge rib. I was surprised! Really surprised!!
There are only three skins on each wing and they go from the back spar around the leading edge to the back spar again. Out of the six skins we bent for both wings the first five worked out fine; then we blew the last one. It ended up a little caddy wonkus so I had to make another trip to Spruce for a replacement skin. It bent fine, thankfully.
It took most of a day to put one skin in place, drilling through the skin, the ribs and the spars, then clecoing.
Tom and I clamped a folded over skin to the table. I got up on the table with a flat board and forced the skin down so the leading edge would bend.
Tom was at the edge of the table and when he thought it was bent enough I would let up and he would try a rib in the fold. We kept doing this till it took the shape of the leading edge rib. I was surprised! Really surprised!!
There are only three skins on each wing and they go from the back spar around the leading edge to the back spar again. Out of the six skins we bent for both wings the first five worked out fine; then we blew the last one. It ended up a little caddy wonkus so I had to make another trip to Spruce for a replacement skin. It bent fine, thankfully.
It took most of a day to put one skin in place, drilling through the skin, the ribs and the spars, then clecoing.
For this operation the skins were held in place by long straps, like the ones people use to tie down their planes.
Tom came each day I was ready to put a skin on, because I needed the extra hands to hold things. The two outer skins were put on first, clecoed only. The inside skin over the fuel tank is .032 and the outer skins are .025. All the aluminum on the wings are 2024 T3 except the spar cap.
I gave Tom a rest for a few days while I did some shimming. I riveted aluminum .025 strips to the top of the ribs and the tops of the spars so that when the center .025 skin was assembled it would flush right across with no dips. It worked.
After all the skins were drilled and clecoed to the 1/8 inch rivet size and everything fit perfectly, it was time to think about sealing the tanks and doing the final riveting.
Pro Seal - have you heard about this sticky stuff? Tom knows all about it now because he had it everywhere!
This is what we sealed the wet wing with.
Tom came each day I was ready to put a skin on, because I needed the extra hands to hold things. The two outer skins were put on first, clecoed only. The inside skin over the fuel tank is .032 and the outer skins are .025. All the aluminum on the wings are 2024 T3 except the spar cap.
I gave Tom a rest for a few days while I did some shimming. I riveted aluminum .025 strips to the top of the ribs and the tops of the spars so that when the center .025 skin was assembled it would flush right across with no dips. It worked.
After all the skins were drilled and clecoed to the 1/8 inch rivet size and everything fit perfectly, it was time to think about sealing the tanks and doing the final riveting.
Pro Seal - have you heard about this sticky stuff? Tom knows all about it now because he had it everywhere!
This is what we sealed the wet wing with.
My friend, Brandon, an engineer on the C-17 project, told me this is what they use to seal the wet wing on the C-17, your average airliner and also a bunch of fighter planes.
Pro Seal is a two part item with a fairly short working time frame. First you clean everything with MEK and then mix this sealer, 1 part to 5 parts on a piece of cardboard. I put marks on the cardboard that represented 1/4 inch and 1 1/4 inch with the hardener being 1 part, and the sealer 5 parts. I then mixed it up using a tongue depressor. Mixing this small amount allowed me to use it all before it set.
We put the bottom skins on first with the sealant between the skin, the ribs and spars. When that was done we turned the wing over, and propped up the top skin so we could work inside the tank. We sealed everything inside the tank and then went over it again. I wanted to do it a third time but Tom thought it was overkill.
You cannot mix this stuff enough. The more you mix it the less chance of having a pin hole leak. Just a little bit of air left in the sealant will work its way to the surface and presto, you have a leak.
I had three small leaks on each wing that were easily fixed.
Pro Seal is a two part item with a fairly short working time frame. First you clean everything with MEK and then mix this sealer, 1 part to 5 parts on a piece of cardboard. I put marks on the cardboard that represented 1/4 inch and 1 1/4 inch with the hardener being 1 part, and the sealer 5 parts. I then mixed it up using a tongue depressor. Mixing this small amount allowed me to use it all before it set.
We put the bottom skins on first with the sealant between the skin, the ribs and spars. When that was done we turned the wing over, and propped up the top skin so we could work inside the tank. We sealed everything inside the tank and then went over it again. I wanted to do it a third time but Tom thought it was overkill.
You cannot mix this stuff enough. The more you mix it the less chance of having a pin hole leak. Just a little bit of air left in the sealant will work its way to the surface and presto, you have a leak.
I had three small leaks on each wing that were easily fixed.
I had three small leaks on each wing that were easily fixed.
I finally bit the bullet and agreed to close up the wing. We put the sealer on the tops of the ribs and the spars, pulled down the top skin and clecoed it in place. Then we went to lunch.
Brandon first said to clamp it down; then he said, probably clecoing it will do since we had no way to clamp it. At McDonnell Douglas they have clecos that work as clamps but we did not have that luxury.
The idea was to let it set for a bit so the Pro Seal would squash down and spread out if it was going to. You dtdn't want this to happen after the rivets were shot. In California it seems they shoot rivets, elsewhere they do other things.
After lunch we started the riveting. Tom inserted the 1/8 flush Cherry Max rivet and I used an air puller. We got pretty fast at it but boy, there was a lot of rivets. The great thing about Cherry Max is they all break off flush and every hole is plugged. I did not have to drill one out.
We eventually had both wings finished, so it was time to do a leak test.
Another call to Brandon to find out how the Big Boys do this.
I finally bit the bullet and agreed to close up the wing. We put the sealer on the tops of the ribs and the spars, pulled down the top skin and clecoed it in place. Then we went to lunch.
Brandon first said to clamp it down; then he said, probably clecoing it will do since we had no way to clamp it. At McDonnell Douglas they have clecos that work as clamps but we did not have that luxury.
The idea was to let it set for a bit so the Pro Seal would squash down and spread out if it was going to. You dtdn't want this to happen after the rivets were shot. In California it seems they shoot rivets, elsewhere they do other things.
After lunch we started the riveting. Tom inserted the 1/8 flush Cherry Max rivet and I used an air puller. We got pretty fast at it but boy, there was a lot of rivets. The great thing about Cherry Max is they all break off flush and every hole is plugged. I did not have to drill one out.
We eventually had both wings finished, so it was time to do a leak test.
Another call to Brandon to find out how the Big Boys do this.
This is what they do but on a different scale. Take your vacuum cleaner, hook it up to blow air, and blow air into the gas cap hole, assuming all other holes are taped over. Go over all rivets and connections with soapy water on a brush and any leaks should show up. And they did. Next step, you are almost done; reconnect the vacuum cleaner to suction and place it back in the gas cap hole. You should have the sloshing compound stirred up and ready to use; then you take a small clean screw driver and put a dab of compound on the spot where the leak is and the suction from the vacuum will pull it through the hole. After about three dabs it won't suck through any more and the hole will be plugged. Is that any good!
It took me about five minutes to do each wing.
The wing tips are from a Thorp S18 and had to be tweaked a bit. Closed up at the front about 1/4 inch, then they fit the airfoil nice and snug. I also had to trim about two inches from it to match the trailing edge, but all in all they worked great. These tips are 11 inches wide and this allows for the aileron to be 16 inches further out toward the wing tip. It also allows for a wider flap.
It took me about five minutes to do each wing.
The wing tips are from a Thorp S18 and had to be tweaked a bit. Closed up at the front about 1/4 inch, then they fit the airfoil nice and snug. I also had to trim about two inches from it to match the trailing edge, but all in all they worked great. These tips are 11 inches wide and this allows for the aileron to be 16 inches further out toward the wing tip. It also allows for a wider flap.
My flaps and ailerons are fabricated much like Clement's. They are larger than a normal Tailwind and very effective. Inside the flap and ailerons there are skin stiffeners, little aluminum angles every 5 inches flush riveted top and bottom. The torque tubes ride on nylon bushings and are very fluid.
The indent faring at the root end of the wing was fiberglased right in position. It was pulled off, cleaned up, trimmed and put back on with soft rivets. I would have to take this off later to cherry it up.
The engine is a Lycoming 0-320 with only 500 hours on it. It had sat for many years in the desert so I had it top overhauled.
The cowling is an Edge Concept and so is the spinner. The cowling needed a lot of work. I had to cut the top sides apart to fit my fuselage and also change some of the shape around the front to match the spinner.
I had to make three carburetor heat boxes before I got one to fit. That seemed to take forever.
The indent faring at the root end of the wing was fiberglased right in position. It was pulled off, cleaned up, trimmed and put back on with soft rivets. I would have to take this off later to cherry it up.
The engine is a Lycoming 0-320 with only 500 hours on it. It had sat for many years in the desert so I had it top overhauled.
The cowling is an Edge Concept and so is the spinner. The cowling needed a lot of work. I had to cut the top sides apart to fit my fuselage and also change some of the shape around the front to match the spinner.
I had to make three carburetor heat boxes before I got one to fit. That seemed to take forever.
The exhausts are stainless steel and made to fit the cowling, It would be cheaper if you could buy a set but you have to make them. Mine have cracked four times but I think I am getting a handle on it now. That is another story.
Everything on my plane is new and most everything is aircraft quality. I tried to keep in mind how certified planes are made, for safety reasons, such as my fuel system. It is very close to a Cessna system and that is not all bad.
The electrical wiring was taken right out of a tried and true diagram in a Bingelis Book.
At weigh in, the plane came in at 968 lb. Not bad for everything I have in it.
I blame the extra weight on my friend, Skip, who helped me wire it . He kept adding all these wires and I don't know what they were for.
Not much more to say other than I love my plane, and I'm happy I am one of the wannabes who finished their project.
Earl Trimble
Everything on my plane is new and most everything is aircraft quality. I tried to keep in mind how certified planes are made, for safety reasons, such as my fuel system. It is very close to a Cessna system and that is not all bad.
The electrical wiring was taken right out of a tried and true diagram in a Bingelis Book.
At weigh in, the plane came in at 968 lb. Not bad for everything I have in it.
I blame the extra weight on my friend, Skip, who helped me wire it . He kept adding all these wires and I don't know what they were for.
Not much more to say other than I love my plane, and I'm happy I am one of the wannabes who finished their project.
Earl Trimble
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The Building of my Tailwind Continued - The Initial Flying - Journey Home
Metal Wing? - Wood Wing?