Light wing build

[qsmx440]

Might as well continue on this at this time.

This next section was done over dec 2014 and through feb 4 2015. It involves the making of the flap and aileron leading edges and then the riveting of the leading edge bulkheads to them. Altogether there are 14 leading edges. I apparently didn't make pictures of the process of bending them but I will describe as best I can. In answer to a question I placed in another thread it was suggested that a slot bender would do the job. I at first dismissed that thinking the poster was describing the wing leading edge and that it wouldn't work on these smaller bends. Wrong! As I gave it some thought I screwed down two 4 foot 1X2" boards with about a 1" space between them and I mounted two pivoting pieces of metal to the workbench to press with and placed the 2024-T3 .016 blank such as where I believed the center to be (note: make the blank a little bigger and trim after the bend. Practice with roof flashing). A 3/4"piece of black pipe was used as the pressing diameter and that was backed up with a 4' piece of 1 X 6 place between the pressing pieces and the pipe to keep it from bending in the middle. All of this was junk stuff cobbled together in a few minutes. With my wife's help we bent these all in an hour or two. The slot bender worked perfectly and is recommended. You can see the set up in the next set of pictures where I move one of the 1X2's over enough to hold the built up laser cut card board LE forms.

Here is a blank pre bent LE laying next to the forms it will be pressed into:



In the above picture note the predrilled holes in the blank. I made up a hole-locating jig out of a spare piece. This was carefully adjusted on center of the nose and then the holes marked. The blanks were first marked according to part number, the length wise hole locations. Then the jig was slid along to each position of 4 holes and marked. Watch out it's easy to get the distances wrong from the diagrams (aileron 40471 and flap 11683). The diagrams all show left wing pieces but they measure from the outboard ends. Right hand pieces are reversed. Easy way to do this is build all the lefties first and place them facing the right ones to lay them out! Remember to remove the covering on both sides before pressing the bulkhead's in.

This next picture shows one end of the pressing and marking the holes in the bulkheads (part #40451, pressing of which detailed in another post if I can find it). In the foreground (dark object going across the screen) is one of the steel arms (there is another on the far end) I press on the straight edge (square aluminum tubing) with, to seat the bulkheads into the LE and the forms:



The bulkheads are marked, removed, drilled, de-burred and then returned to the forms and clecoed.. I tape the rear edges to help form them and take the pressure off of the clecos.

These are the tools used:



Note: I clamped the trigger and used a foot switch. This has the benefit that the squeezers clamp and hold until I release the trigger clamp allowing me to whack the top of the squeezer to finish the rivet to the correct diameter of about .040. Rivet the upper nose rivet first then the others. After some practice on scrap I had no missed rivets or damaged skin. I did need to drill some of the first ones because they wound up crooked a bit but after that I leveled more correctly before pushing the foot switch.

Notice the 1/4 20 bolt in this picture (between the drill chuck and the cleco) is drilled offset a few thousandths. This was bolted to the upper squeezer arm and the smaller 3/16? rivet set was inserted in it. I adjusted it to be as outboard as possible and it fit OK into the bulkhead. Also note the reinforcement scrap pieces used to spread the cleco load on the holes(attached to the cleco for the picture but actually used on the far side of the hole from the cleco body). With these 3/32 holes and clecos they don't like much pressure and the straps help strengthen and protect the holes:



And the final result (14 pieces) along with a taped mockup of a flap:



About 40-50 hours but pretty much built from scratch and they are very straight and uniform. Next comes riveting the hinges and figuring how to center all the hinges on the aileron and flap spars. I have not figured that out yet.

[qsmx440]

Ok these are from the beginning of my build and were in the now "defunct" blog section originally. SJ made these available for a short time to copy and past. Anyway sc.org is my build log so I am moving these.
First one:

qsmx440

elevator

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by qsmx440
, 03-18-2013 at 12:11 PM (472 Views)

In keeping with yesterdays post this picture shows the layout of my "temporary" table to build all six tail pieces. I was still at the "do I want to do this" stage and did not want to spend my time building a table like I now have. This does show you can take some scrap lumber and old plywood and make a form surface. The underside of the plywood was shimmed at various locations to achieve a flat surface between the various plywood scrap pieces.
The elevator and rudder required different bending at different locations. I rolled the whole tube to the "least" (largest radius) bent area first and then concentrated on the increasing bend areas as needed finishing with the most bent (smallest radius) areas last. Again be sure and put a clamp on the tube to keep your hand on and give a visual level indication while rolling or you will get a multiple direction bend in the tube.





Here is a tacked up all most finished tail. I did eventually get all the ribs made and installed. They are the most difficult part in as much as they taper. I found the best way to build them was to make the taper correct, make the blanks a couple of inches to long on each end and then cut out the center so as to get the length dimension I needed. I used a Harbor freight shear/brake,roll 3 in one machine that for 399 on sale is a very handy unit for building this kind of airplane. It was my brothers but it now lives in my garage for the time being.



The 6 parts of the tail is a great thing to build first since they are easy and when done you have some airplane looking parts to hang on the wall for inspiration. I don't have any more tips from my building of these since it was almost three years ago when I built these. I will say to store them inside . Mine are stored inside but still have developed a light coat of rust. I am planning on taking a TIG welding class before finish welding so I didn't want to paint them yet.

[qsmx440]

And another from the "way back machine":

qsmx440

stabilizer

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by qsmx440
, 03-17-2013 at 01:56 PM (390 Views)

Swedging the stabilizer tube the old fashioned way. This little tool is made from a bolt with the head cut off, a couple of nuts and a stack of oversized flat washers. The nuts are tightened and then the center two washers are ground/sanded on a belt sander to the "swedge" dimension you want. The outer washers on each side are ground down to the original size. The whole thing is tapered on each side of center so you can tap it in and then "hog" the hole a little by moving the handle in an arc each little ways in. Use plenty of oil in this process. I had no problems doing this and no cracking. A long rod is used in the far end to drive the swedge back out when done. I turned it several times driving it in each time to assure an even dimension.





Next the leading edge of the stabilizer needs to be formed into a semi circle. I made up the form blocks as per Piper drawings on a flat surface for the balanced stabilizer on Buggs site and then used a cheap Harbor Freight roller to form the bend. Note in the picture the clamp placed on the part. This clamp is needed to keep the pipe level or perpendicular to the roller machine. If you just start rolling back and forth without keeping the same line on the pipe you will get a double bend that is difficult to impossible to deal with. I like the roller machine since it will not kink the tube like other methods and there is no need to fill with sand or other measures. For $60 on sale it's a good deal.When your done the pipe should lay flat and true in your form blocks. Don't forget to order a couple of extra feet of tubing as the machine cannot bend all the way to the end of the tube. After you are satisfied with the bends lay the tube in your form and cut to length. I like to cross over all the parts on top of each other before cutting to make sure everything is adjusted correctly to fit the form.



And here is a picture of the parts at the beginning of the tack weld stage. I purchased the "C" channel I used in the tail pieces but made all the tapered ribs used in the tail from sheet steel and that will be a subject of a future blog. All of the curved pieces in the tail were made on the roller machine and turned out very good. Both sides of the stabilizer and elevators must match IMHO although because the prop wash is applied differently to each side the pressures will still be unequal at least in power off mode the tail should be balanced.




This work (all 6 pieces of the tail) was actually completed in 2010 and was the first parts I made to see if I really felt like taking the project on..

[qsmx440]

Yet one more:

qsmx440

Wing compression strut parts 2

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by qsmx440
, 02-03-2011 at 11:20 AM (11502 Views)

Well I have finally got back to work after 3 months working ? Well I mean on the plane. Actually I'm not building a Piper clone airplane. I'm building a small part of the 13 rib metal wing. Like eating an elephant. So this is the first time I attempt to post pictures and I'm not sure how it will go. As to my earlier blogs I was attempting to decide how to build a light weight wing for my attempt at building a 150 horsepower 1320# gross weight supercub clone. I finally decided on recreating the PA-18 13 rib wing as per the drawings on Christian Sturms site: supercubproject.com The parts I build for this project will follow those pages in the "drawings" section of his site (the "drawings" button is in the upper right hand corner of his home page). Once you get to the drawings page enter 10062 in the search box for the first part we will discuss. So in my first blog picture (remember you can blow it up by clicking it a couple times)


are parts in various stages of completion so that you can see my thinking. Note my favorite flyer in the cage (we have cats unfortunatly) At 14 years old she has lost her medical but still flys some (ultra light catagory only) Figuring the order to make any parts is half the work usually and actually the challenging part. After you've figured out how then stamping widgets is anti climatic. In the picture you see 3 drawings from Christians site (10072) Drag strut front foot, (10062) rear drag strut foot, (10021) "N" strut gussets. Diagonally in the picture is an actual drag strut with the front foot clipped on to it. I cheated a little on this as I ordered, from Dakota Cub, 1 ea foot front and rear foot and drag strut tube, drag wire pull and nipple etc so that I would have a pattern to decide how to layout tooling and then check the quality of my work. In the second picture


you see the rear foot (10062) in various stages of completion. The triangle piece of flat aluminum is the first blank which was derived from a paper pattern. After making the first blank the rest were scribed around it to mark the rest of the aluminum blanks. I used one of those 30" shear/brake/roll that Harbor freight sells and my brother owns to cut the blanks. I did one with hand shears just to prove it could be done. It turned out fine but the shears tended to curl the blank slightly. A whack with a board brought it back into shape. Note the finished (factory) piece sitting on a blank (bottom left of second picture) to mark lines on the blank to center the bending board on. Two centering lines were scribed on each blank (flop the pattern piece over to make second mark and don't worry about width of marks just align the edges of blank and mark. You will center wood form between the marks, distance between the marks doesn't matter). In the third picture


the blank is centered under the bending board (7/8 wide piece of scrap finish wood (home depot 1" finish? measures 7/8") with the bottom edge "broke" by hand with a piece of sandpaper for the "radius" edge). The previous center scribed lines are used to eyeball the board to the center of the blank. Pressure is brought on the board by the milling quill being lowered onto the top of the board and locked. In the forth picture


a scrap of .032 4130 steel is squeezed under the edge of the aluminum and while pressing in it is tilted up a bit,presseng in again and then a second thicker piece of steel is pushed under that one and it's bent some more (repeat lifting and pushing in on the "wedges") until the side reaches about 45 degrees. At this point the blank is turned around and the other side is bent to 45* also.


In the last picture the milling vice (between the jaws) is positioned under the quill and the partially bent blank is placed between the soft jaws on top of a scrap 3/4" square tube (to keep the bottom of the part flat while you finish bending it since there is a hole in the center of the vice), the quill is lowered for top pressure on the board and the vice jaws closed to complete the two side 90* bends. Top pressure is needed while bending to keep the bottom (center of the part) from taking a curve. Some repositioning of the "X" axis of the milling table vice is needed while tightening the jaws. Note: cut your blanks so that you are bending across the grain. The blanks are 5052 aluminum from onlinemetals.com. About $20.00 for all the feet needed and the "N" strut gussets. The two certified pieces were 7 an10 dollars respectfully. Practice makes the pieces bend up perfectly on both sides so they match. For production, do several parts 1 step at a time on all parts before moving to next step. Works out to about 10 minutes a piece total/part once you've done a couple practice pieces. Finish corners on a belt sander. A slot has to be milled on the bottom like in the factory piece. I will use a ball end mill but corner holes could be used and maybe a dremmel tool or small hacksaw blade with file finish. So if you have followed so far does my description and pictures lead you to think you could build these pieces for the Piper wing?? Suggestions to improve (this works but maybe someone has a better way)? Thanks

[qsmx440]

And I think this is the last of the "old" stuff I will move. A lot of what follows is already resolved. I think I am missing a lot I have done so will have to search thousands of pictures to catch up. Am actually back to work on this after a couple of years for back operations and dying/aging parents and aging myself. Also I have just copy/pasted without reading any of this stuff. :
qsmx440

Supercub PA-18-150 clone

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by qsmx440
, 12-02-2010 at 10:31 PM (1773 Views)

Well if this blog business works this will be where I document my Supercub clone build. In reality this project started about 8? months ago and has been scattered over a few different sites. If this looks good then this is where I will post pictures, build notes and questions I will have to help progress.

I have had my private license since the late 70's? but I was inactive for many years. A few years back I started flying a Quicksilver Sprint ultralight. The performance was an eyeopener after the Cessnas I was used to. Other than top speed it got airborn in 50-60 feet and was at 800' agl by the end of the runway at my airport. Soon I wanted a bigger airplane with a little more speed and endurance. In all my prior flying I had never paid any attention to the Piper products considering myself a Cessna man. Another thing I had found was that I liked the owner maintenance idea of the homebuilt. I first looked at the CH-701 and considered building my own plane for the first time. But.. Something was not as I wanted. I moved to the Bearhawk but decided it wasn't quite right as a fit either. Somewhere along the way I discovered this site and also Christian Sturms supercubproject.com site and the "drawings " button. Wow! I could do this! And here I am.

I need to add here this is going to be an elsa aircraft so the gross weight will be set at 1320#. I intend to reach this goal even if the plane winds up being a single place. I plan on empty weight not exceeding 950#. Basically the mission is boring holes in the sky. Reaching this goal will mean that the A/C will be built with:
no electrical system
no interior
non adjustable seat
maybe one wing tank
maybe no wing tips (to be discussed)
small (600 or 850) tires
wood prop


At present I have :
A sheet of .020 titanium for the firewall
A box of new 1980's Schneider ribs for the main wing (no control surface parts)
A 1977 Supercub fuselage (no corrosion but some bad past repairs)
A 1957 narrow deck O-320 Lycoming w/750 smoh w accys
firewall forward cowling and nose bowl
Sensenich 74-52? prop with spinner
2 front and 1 rear lift strut
2 gear legs (no cabane v or suspension)
set of single puck Cleveland brakes
all 6 tail pieces through "tacked" (the only real building so far) completely from raw materials
new main wing spars
partially completed seat
stabilyzer jack screw assy complete (needs new screw)
engine mount with a cracked tube (upper right?)

total spent so far about 13,000

I still need:

fuel tanks
main wheels and discs
suspension
tail wheel
compression struts and drag/anti drag wires
controls and cables/pulleys
one rear lift strut
four ea jury struts and mounts
heel brakes
to build pedals, torque tube, etc etc etc..
Stewarts covering system ($3200)
boot cowl parts


I am busy for the next 4 months on a contract job that has enabled me to purchase as-I-go the above parts so no actual building now. I look to be freed up in the spring.

The main decision I am looking at now is how I will build my main wing. I have purchased d&E spars

[brown bear]

I dont want to rain on your parade but---you said -- "I need to add here this is going to be an elsa aircraft so the gross weight will be set at 1320#."
Are you sure ?? here is a good read about it in kit planes http://www.kitplanes.com/issues/29_3...t_20376-1.html
So it looks like you are trying to build a E-AB with a 1320 GW that you can fly light sport ? but you may be it trouble there also as you will get know credit on the 51% check list for repairing parts that are off a type certificated aircraft . like " 1977 Supercub fuselage (no corrosion but some bad past repairs)" I know that in the past this was not the case but that is now in the past !
Go to the FAA web site and look up "Amateur-Built Fabrication and Assembly Checklist Job Aid"
I am not trying to be a know it all just hopeing to save you some heart trouble down the road .
Doug

[tempdoug]

Will you be playing off pavement or grass? Scrap the wood prop for a 8440 catto and the 8.50s for airstreaks. API 6131 tailwheel and be very conscience of covering coats, make sure you can see the fabric weave when done.. One wing tank works just fine if not planing on going anywhere but i would put in a header. Put mounting plates or tabs and put the heel brakes front only. Heel brakes from Don Jones on ebay. Jay at Javron makes nice aluminum wing struts. He also makes a lightened version of a lot of the pulleys. Rear seat like Bill Rusk made up. Air tractor has a fabric that is strectched or fastened to a seat skeleton that they put in there million dollar airplanes looks comfortable and light. If you need a engine mount Univair usually has theres onsale late winter early spring for a month or so. Call them and find out when. Park brake on right side only for hand propping? Ive never used my left one yet in 800 hrs. Slick mags will save some. Spinners=Yuk. I like this.

[Cub junkie]

deleted

[qsmx440]

Yep very old thread and you are correct about E-AB. AntiCub actually straightened me out on this at the beginning of this build: From December 2010:

Quote: "Awesome! I know we talked about the Challenger and quicksilvers before. So it's ironic that I'll be starting a Bearhawk Patrol soon for most of the same reasons. As soon as I get some home improvements done.

Just a note on Semantics, E-LSA refferes to previously flying ultralights that have been inspected and registered as LSA's. I believe what you'll be building is an Experimental - Amature Built aircraft that happens to meet the LSA definition.

Phil"


If appendix 8 is still the determining factor I should be fine. I did check with a DAR a few years back and he said it was fine. Now that said as I get closer I'll find out for sure and then buy a new fuse if needed. I don't plan on building one. The problem with parts is the FAA doesn't seem to have any problem with certified parts that have never flown but does have a problem with "salvage" parts as they call them. If you use any salvage parts you lose the whole section so basically I can't count any of the fuse section work which I think even includes cover. I am using Dakota ribs (new PMA'd which actually included a STC in the package) in the main wings but I only lose the ribs part of the wing section. Appendix 8 called out the fuse at 19% of the build if I remember straight. Today I am back fighting with the aileron center bellcrank/hinge steel rivets and I finally had a win just before lunch getting 4 steel rivets in the left aileron without mushing them over to one side!! Got 4 to go on the right side and then I can begin putting the ailerons together in earnest next weekend while my wife's gone for 4 days. I am disappointed I seem to have lost the pictures of casting stamping dies for the aileron/flap bulkheads and also pressing them. I'll probably have to do a few more for pictures.

I dont want to rain on your parade but---you said -- "I need to add here this is going to be an elsa aircraft so the gross weight will be set at 1320#."
Are you sure ?? here is a good read about it in kit planes http://www.kitplanes.com/issues/29_3...t_20376-1.html
So it looks like you are trying to build a E-AB with a 1320 GW that you can fly light sport ? but you may be it trouble there also as you will get know credit on the 51% check list for repairing parts that are off a type certificated aircraft . like " 1977 Supercub fuselage (no corrosion but some bad past repairs)" I know that in the past this was not the case but that is now in the past !
Go to the FAA web site and look up "Amateur-Built Fabrication and Assembly Checklist Job Aid"
I am not trying to be a know it all just hopeing to save you some heart trouble down the road .
Doug

[qsmx440]

Mostly or maybe all pavement. ?? I am planning on one tank and the small header. Probably no electrics and yes on the Catto. I am intrigued with the idea of no fuselage cover maybe like the "Bobber".? The worst part is being nose heavy with the O-320 and again as I get closer I may have to rethink that. I was given a set of cub wheels/tires with expander brakes and for my purposes that may be what I start with.

Will you be playing off pavement or grass? Scrap the wood prop for a 8440 catto and the 8.50s for airstreaks. API 6131 tailwheel and be very conscience of covering coats, make sure you can see the fabric weave when done.. One wing tank works just fine if not planing on going anywhere but i would put in a header. Put mounting plates or tabs and put the heel brakes front only. Heel brakes from Don Jones on ebay. Jay at Javron makes nice aluminum wing struts. He also makes a lightened version of a lot of the pulleys. Rear seat like Bill Rusk made up. Air tractor has a fabric that is strectched or fastened to a seat skeleton that they put in there million dollar airplanes looks comfortable and light. If you need a engine mount Univair usually has theres onsale late winter early spring for a month or so. Call them and find out when. Slick mags will save some. Spinners=Yuk. I like this.

[brown bear]

GSMX440
It sounds like you are on top of it and will have a fun plane when done !
Doug

[D.A.]

a cheap Harbor Freight roller to form the bend...I like the roller machine since it will not kink the tube like other methods and there is no need to fill with sand or other measures

I guess I missed this the first time around. Tell me more about this roller. Still like it, still recommend it? Looks like exactly what I'm looking for.

[qsmx440]

Yes it's an excellent piece for the money. You do have to keep the tube the same way up or down as you increase the bend and it does require a couple of feet of waste that you cut off. I think I made a line down the pipe with a marking pen. My son used it for stainless tubing on a bimini he made for his boat and others have used it for various projects. For the tail feathers it is ideal. Make up your pattern on plywood with some scrap pieces of wood screwed here and there and then roll and check the fit, rinse and repeat, do the areas with a tighter radius last. making the tail tubing was one of the easier projects.

I guess I missed this the first time around. Tell me more about this roller. Still like it, still recommend it? Looks like exactly what I'm looking for.

[qsmx440]

2016

More boring "kinda" scratch built stuff

5-23
Still working on riveting skills for the 4 center steel rivets in the left aileron bellcrank-spar-hinge sandwich. Started to get some decent ones after 100 practice ones in scrap. I tend to bend these over more than drive them down straight and centered. Think I have a system. The big problem besides skill on this is steel rivets are waaay harder to drive and this is compounded by the bell crank head side rivet heads being up under the bell crank flange around a corner. You need 5 hands and the arms of a boiler maker. Oh and just to make it interesting the rivets on the hinge side are right smack against the edge of the hinge bends! Whew. (Dinking around with some progress)
3.0 hrs

5-24
Drilled and cleco-ed the above parts in the left aileron. Shot my rivets. Not totally satisfied with them. Going to sleep on it. 3.0 hrs

5-27
Eureka! Did the right aileron and discovered I had been using slightly to long of a shank on my rivets which along with the gun "skating" off the head was the problem. I solved the skating problem two ways: First I started stabbing the trigger for extremely short bursts checking the shank between bursts, If it started to bend in any way I would slightly adjust my next "shot" to straighten it up. Second was to give myself some training wheels on the tool/rivet interface. This consisted of a strip of 220 grit sandpaper set between the tool head and the rivet (moved to a new spot on the sandpaper after each burst). I found as I practiced I didn't need the sandpaper so much after the first couple of bursts. My rivets compared perfectly to the factory rivets in a wrecked aileron sample I have. I will go back and replace my rivets in the left wing as I am not happy with them.

A little thought on assembly order and other problems. First to install these you have to notch both sides of the spar to fit the bell crank. After notching and before riveting this makes the spar extremely weak and bendy. Keep it on the bench or blocks as needed to protect it from bending or if you must move it at this point tape a long board with spacers to it to protect it! I'm not done yet but it appears the order is: Rivet 3 hinges and center bell crank, then rear ribs, then rivet the leading edge assemblies with the bulkheads already installed and riveted while mounted in a jig. The twist is built in as you rivet the leading edge on. Check hinge alignment constantly. The previous was "beta" and after I've actually finished one I'll update as needed. I would say these rivets have cost me 1 year of being "stuck" mentally (along with a couple of back operations and other excuses) on this project and about 50 hours of failure building riveting jigs and other useless stuff. In the end this turned out to be a manual/skill operation. A rivet squeezer does not have the "umff" to do this IMHO. I ordered the spars originally from Javron and I should have just had him install the center hinge bellcrank assy before shipping. I set a deadline a week ago of just that if I didn't figure this out. I was just going to order new ones if I didn't get this job done in a week and scrap bin this stuff!

During this build I have tried to use Harbor Freight type tools that the average Joe could afford or purchase to do this stuff. I have a fancy squeezer, laser cutter/engraver, 3D printer and a small machine shop and some other upscale tools but they were mostly for convenience. In the pictures is that weird shaped hardened "buck" mounted in the machinists vice that I don't know how I could have done this without it. I did get lucky a few years back on a craigslist buy from a retired Boeing mechanic and got a bunch of riveting stuff and along with a bunch of other bucks this was in the box. You will have to duplicate it's weird bends to do this job. Also I used the buck on the "factory head" side of the rivet (up under the flange on the bell crank which is the problem), The shop side was done with a flat end tool with a flat ground on one side to get closer to the edge of the hinge. It appears to me the factory did the same thing! The gun is just a HF 55 gallon drum "can opener" 10 bucks on sale. Air pressure set to 40 lbs. It comes with some cutting tool that could easily be ground to mimick my fancy driver and I'm sure sure would last through the 8 rivets on this job. Buy 100 rivets (I'll edit in the part number later. 7-8- dollars) and get your skill up before destroying your spar/hinges.

Well I'm off to find Pierce's posts about his jig and then find the scrap to build one.

Pictures:

Practice piece before I figured this out. Note factory side over flattened.


Here is alignment in edge plane hinge centers only which is all that matters at this point. Laser is in foreground out of the picture but is firing through center of outboard hinge. Picture is of center and inboard hinge. Laser is hot glued into position to be centered on the outboard and inboard end hinge and then the center hinge is hot glued into position before being clamped and drilled.



Some of the tools: note the weird buck in the vice and the ground off driving tool laying on the vice screw.


I will add a picture of the finished rivets later. I forgot to take one!?

[qsmx440]

Some weeks you should just do something else!! I even had an example sitting there.


Only the end bulkheads are riveted, not the top and bottom of the leading edges, so only 14 rivets to remove. I must have put my shoes on backwards that day. I remember checking and triple checking and changing my mind a couple of times as I was really worried about doing this. uggh!

[qsmx440]

Ok right way round now! Minus 6 hours on the build. But for what it's worth, that aileron was the first I mounted the leading edges to and I got progressively better at riveting (and removing rivets) while building the flaps and now it seems to be a piece of cake. I still have to mount the leading edge to the right aileron but it should go fast now, maybe 3-4 hours.

After the right one I still have to go back a "jig" all four controls surfaces and finish the top and bottom leading edge rivets.

That's better:


I am not sure why the "old" upside down picture is still attached to this post but the aileron is correct now!

[qsmx440]

So continuing this build I have finished the flaps and ailerons to the point of inspection, meaning for the most part I pushed through the build of these four items and left the odd dodgy rivet and now will go over these with a fine tooth comb and mark anything that doesn't meet specs and will replace that item.

I built the flaps first with the thinking that my skill level would improve with each item and indeed that was the case. The first flap took a couple of weeks and the last aileron took two days. The first flap will require the most replacing of rivets and the last aileron will not require any corrections.

I have a question on the hinge rivets on the flaps and the outer hinges on the ailerons. I used AN455A - 4 rivets. These are the soft aluminum rivets. Should I change these for a harder alloy?? The center aileron rivets are the correct steel rivets so they are fine.

During this build I finally ponyed up for a hand powered rivet squeezer (159$ with sets and gauges). I should have bought that originally instead of the air powered equipment I got.


First picture shows one of the ailerons with center hinge and horn mounted. All parts were coated with primer (zinc chromate) before being riveted together.




Here I am milling slots for the trailing edge to fit over the back of the ribs. Note: I used the D&E trailing edge material. I believe it to be a little heaver and not as good as the bent piece piper specs. It does work but has a little "bump" on both sides. I made some wood (3, one inside and two outside bevels) to keep the vice from collapsing material. A bit futsy so practice on some cutoff scrap before committing to the real piece



Here the aileron horns and hinges riveted with the steel rivets that were so hard to do. I would recommend buying the spars from Javron with these already done to this point



This is the D&E trailing edge with one slot machined.


The next couple of pictures are of and aileron with the ribs attached. NOTE: do not do as I did but instead follow Mikes advice and attach the "end" bulkheads of each leading edge section at this point! I didn't and it caused way more work than should have been necessary. Another windmill 10 hours!



Cleco'ed and taped together for now.

This all happened over weeks so I'll give this a minimum of 30 hours Mostly learning to rivet and remove bad rivets.

[mike mcs repair]

milling trailing edge, hmmm i might have to try that!! (piper style...)

any hints or lessons you learned?? so I don't have to learn the hard or exciting way of parts flying across the shop (again..)

So continuing this build I have finished the flaps and ailerons to the point of inspection, meaning for the most part I pushed through the build of these four items and left the odd dodgy rivet and now will go over these with a fine tooth comb and mark anything that doesn't meet specs and will replace that item.

I built the flaps first with the thinking that my skill level would improve with each item and indeed that was the case. The first flap took a couple of weeks and the last aileron took two days. The first flap will require the most replacing of rivets and the last aileron will not require any corrections.

I have a question on the hinge rivets on the flaps and the outer hinges on the ailerons. I used AN455A - 4 rivets. These are the soft aluminum rivets. Should I change these for a harder alloy?? The center aileron rivets are the correct steel rivets so they are fine.

During this build I finally ponyed up for a hand powered rivet squeezer (159$ with sets and gauges). I should have bought that originally instead of the air powered equipment I got.


First picture shows one of the ailerons with center hinge and horn mounted. All parts were coated with primer (zinc chromate) before being riveted together.




Here I am milling slots for the trailing edge to fit over the back of the ribs. Note: I used the D&E trailing edge material. I believe it to be a little heaver and not as good as the bent piece piper specs. It does work but has a little "bump" on both sides. I made some wood (3, one inside and two outside bevels) to keep the vice from collapsing material. A bit futsy so practice on some cutoff scrap before committing to the real piece



Here the aileron horns and hinges riveted with the steel rivets that were so hard to do. I would recommend buying the spars from Javron with these already done to this point



This is the D&E trailing edge with one slot machined.


The next couple of pictures are of and aileron with the ribs attached. NOTE: do not do as I did but instead follow Mikes advice and attach the "end" bulkheads of each leading edge section at this point! I didn't and it caused way more work than should have been necessary. Another windmill 10 hours!



Cleco'ed and taped together for now.

This all happened over weeks so I'll give this a minimum of 30 hours Mostly learning to rivet and remove bad rivets.

[qsmx440]

Well I don't think Piper did these this way at all. The diagram for the parts shows them being cutout before being bent. This D&E part looks almost like an extrusion or at least a heavy piece of sheet metal. You will notice it's just a piece bent over on the trailing edge and in the front has two lips that converge on each other with a gap. It was difficult to deal with. Because the holes are not important structurally you could just cut and hog them out and then cover the mess up. Since I had a milling machine I made up an inside piece of wood that fit the inside shape perfectly and then two outside wedge shaped pieces that were shaped to bring the whole sandwiched mess back to square to mount in the vice. High speed plunging (ball nosed cutter) cuts moved in the X axis very slowly finally produced an acceptable part. After each cut the wood pieces which were about 5" long were slid to the next position and repeat. Tedious at best but I listen to the radio and time goes by. I'm not earning a living here.

Mike any ideas on the -4 rivets for the hinges? I did get the aileron horn rivets right. I used the 455 soft rivets (for the aluminum ones). Is that OK or do I need stronger alloy aluminum hinge rivets?

As to tips- My posts probably mostly serve as warnings how not to do things. I seem to have to do stuff over and over. It's hard when there isn't a manual on assembly order. Most of my pieces seem of good quality but then I assemble in the wrong order and have to do it all over again. The information I know is available somewhere but over the years I sometimes forget what I used to know.

[qsmx440]

So this is to conclude the aileron and flaps build I did over the past few weeks.

First the forms that were used on to build the leading edges a year or so ago were used again to jig the final build. They were built on a laser cutter (affectionately referred to as "the cheap Chinese laser" in the CNC world.) that cost me $470.00 delivered to my door. I have both a 3D printer and this laser cutter. I like the 3D printer but I would replace this machine in a heart beat if I had to. It is the goto machine for a lot of projects. I make custom stamps ( I should make some for SJ I guess!) and etch glass and aluminum (anodized) and it cuts 1/4 inch plywood. The only thing I would do is replace it with a bigger one.


The forms were designed using the really poor software that came with the machine. I have modded the machine with air assist and adjustable table, two must haves for the machine. Here it is cutting the heavy cardboard for the forms:





And the final product, single piece and several pieces glued together which makes a very strong form you can easily press aluminum into form and the jig the "bulkhead" ribs and rivet.


And here is one of the controls in the jig and being final riveted.





The upper angle iron was stood off the same distance as the form bottoms and then the angle iron was adjusted to have the 3/8" twist on the outboard end before riveting.

Using "winding sticks" to confirm twist:


And all four controls finished except aileron ends since I have to order some AN3 steel rivets to make the end ribs.


I started to build the wing hanger brackets but I think I will switch gears and make the wing false spars next and begin assembling the wing to make sure the ailerons, flaps and wing bottoms all line up correctly. These parts were scratch built except for the spars and hinges and took about 100 hours for the parts in this post. I believe a forth assembly would only take 8 hours total and be a better product but such is reinventing the wheel.

[mike mcs repair]

the Univair trailing edge blanks come screwed together, and with no holes.... so milling a slot seems like it would be worth a shot... instead of drilling 4 holes and dremeling the scrap out for each rib.... now to see if any scrap is around here...

[qsmx440]

Here you go Mike:

First the pieces as I stored them away


Here they are as inserted in the blank and squaring up the sides for mounting in the vice.


And the end mill profile, I think it's a 3/8"



I used the fastest speed my Charter Oak mill would go. Very slow "X" feed. It did work good and didn't take very long to do. You do need clearance for the blank on the sides of your mill but you can do half and then turn it around if that works in your shop. Using the Piper style folded piece should work even better since the end is closed instead of like the D&E which wants to spread.

I think I'm going to move on to the wing false spar sheet metal. Lacking any thing wider than my 30" 3 in 1 machine I could roll and form the pieces 30" at a time and spot weld AND flush rivet them together to get the 60 and 45" pieces or maybe design more cardboard forms to cut in the laser and then "slot" bend like I did with the aileron/flap leading edges.??

[Jonnyo]

Spaincub that seems like a really good idea on the face of it. One thing that would concern me when using CF or even heavier walled metal parts in a wing is could you be introducing stress points the original designers didn't want. Is everything designed to bend and flex together with each part designed to do it's share of flexing in heavy turbulence? If one part winds up to stiff then another part has to flex more? I once flew through something that made my Cessna 172 fuselage "oil can". That was not a pretty sound! Smashed an expensive camera on the ceiling at the same time. Planes need to bend and not break. BUT CF struts would allow an encapsulated nut and a bonded foot on each end probably cutting the overall weight in half at least. My completed 14222 compression struts (the main ones with a foot on each end) using standard rivets and my own billet inserts weigh 8.68 oz. each. I have one that is using Dakota inserts and with I will have to assemble it with bolts and that one comes in at 11 oz. I ordered all my tubes precut from Dakota (beautiful by the way and perfectly cut) but one replacement they sent had the inserts already in it and they are "stuck" in the tube so I can't really see what the difference between theirs and mine is. They may be glued in somehow? I'll just use them as is. I didn't "lighten" my inserts as much as the Piper original cast ones so another ounce or two could probably be shaved using originals.

Do you have a picture of your compression struts with the foot on each end? Any new ideas on compression struts? Thank you.

[qsmx440]

Do you have a picture of your compression struts with the foot on each end? Any new ideas on compression struts? Thank you.

I thought I had posted pictures before but I couldn't find them so I dug around and came up with these from 2010 or so:
First I used a block of wood to press with and my milling machine vice adjusted to press into. I didn't own a press back then so I used the machine quil to force the blank into the mold. Quick and dirty.Note extra pieces of stiff sheet metal on each side to help make the bend even.





Various pieces finished and unfinished for compression strut builds. Miss my bird!



Here is the completed bend. Note the bottom lands on a piece of steel to be bent back to flat at the end. Without that the bottom "bows". Also note soft jaws inserted at end of bend and that PVC covering is left on blank during the bend.


Starting to put one of the "N" struts together:



A foot starting to be riveted


The slug has to be installed before the last rivet is put in.


Here is the completed stack ready to build the wings.


Hope this helps and I am sure I posted some of this a few years ago but I can't find it now. This was all scratch built except for the tube blanks which came from Dakota Cub. I was not able to source the correct tubing (size, corner radius, and thickness) anywhere else at that time.

[Jonnyo]

I thought I had posted pictures before but I couldn't find them so I dug around and came up with these from 2010 or so:
First I used a block of wood to press with and my milling machine vice adjusted to press into. I didn't own a press back then so I used the machine quil to force the blank into the mold. Quick and dirty.Note extra pieces of stiff sheet metal on each side to help make the bend even.





Various pieces finished and unfinished for compression strut builds. Miss my bird!



Here is the completed bend. Note the bottom lands on a piece of steel to be bent back to flat at the end. Without that the bottom "bows". Also note soft jaws inserted at end of bend and that PVC covering is left on blank during the bend.


Starting to put one of the "N" struts together:



A foot starting to be riveted


The slug has to be installed before the last rivet is put in.


Here is the completed stack ready to build the wings.


Hope this helps and I am sure I posted some of this a few years ago but I can't find it now. This was all scratch built except for the tube blanks which came from Dakota Cub. I was not able to source the correct tubing (size, corner radius, and thickness) anywhere else at that time.

Nice work. Thank for your reply.

[Jonnyo]

Steve, I've been thinking about your post and I would imagine that some of the clipped wing T-Crafts have doubled up ribs for the very same reason. If I remember correctly the T-Cart has the same compression members, or at least very similar. I guess that would stand to reason since the same guy designed both airplanes. I also thought about your comment about running a compression strut at top and bottom of the spar. By doing that you're basically re-inventing a Stearman compression strut (without the cross bracing). I think what Chris and I may do is create something like what you're talking about for our ship. Rather than a single tube, we'll create a truss beam (there's that deeper web strength again) similar to a Stearman compression member or doubling up the stock Piper compression members.
Once again Steve, I owe ya'

Thanks guys, great thread. Here is a photo of a Stearman compression strut.

I have always wished people would bring their unfinished planes to airshows. Not much to see or learn from all of those rows and rows of planes, once all of the glossy paint dries.

[Jonnyo]

This thread is just another example of the knowledge in this group. Really interesting. As far as cable being used in "squaring" aircraft rigging, remember that most aircraft up into the thirties were braced with cable. The Jenny had flying and landing wires that were cable back woven and soldered. Once rigged, you usually don't have to touch it from then on. The trammeling cross braces on my Travel Air are made from rolls of "Hard wire", hence the term hard wire bracing. The wire is simply loped through a turnbuckle eye, bent back over and run through a wound ferule and bent back. The compression members are just ribs made out of 1/4" solid spruce rather than the normal 3/16" spruce. They also glue a diagonal piece of 1/2 or 3/4 (I can't remember) square spruce lengthwise to strengthen the rib and that's it. I guess what I'm trying to say is there are a lot of ways to skin a cat when it comes to maintaining wing squareness.



The compression members are only there to keep a preload off of the ribs. In other words, the two spars are two sides of a box. The trammel wires are there to square the box but in order to square the box you have to draw the wires in an appropriate way to produce that squareness. However, when you draw the wires in you put in inward pressure on the spars. The compression members are there to hold the spars apart, creating the final two sides of the box. Properly done, there should be no preload or compression of the ribs. Also, there really shouldn't be any "Shear" on the plug in the square aluminum Piper compression member. The bolt which goes through the spar is basically just a pin. Some Pipers didn't even use steel bolts. The plug is just there to hold the bolt (pin) in. Once the square tube is pressed against the spar web, there shouldn't be any shear load between the tube and the plug. The Stearman, for all its load carrying and G pulling capability has aluminum bolts holding the compression members in. A Pitts (I believe) has wood compression members and drills holes through the spars to run the trammel wires through and tightens the nut on the other side of the spar against an angled wood block. The Travel Air even has hard wire bracing in the fuselage bays as does a Jenny. Wires or cables or anything "crossed" in a trammel bay is not designed for compression in any way, only tension. The cross braces like Piper's tank bays are both compression and tension. You could build the entire wing with either. And if you have a stressed skin wing, wood or metal, you don't need internal trammeling or Vee wing struts at all (The Maule is a long story). Chris and I could build our wood SC wings (actually Wag 2+2) with wood compression members if we wanted.
Many different ways to do the same thing and they all work. Good discussion. Sharp group!
D.A.

How does a Maule do it differently?

[qsmx440]

Thanks guys, great thread. Here is a photo of a Stearman compression strut.

I have always wished people would bring their unfinished planes to airshows. Not much to see or learn from all of those rows and rows of planes, once all of the glossy paint dries.

WOW my old thread! I almost forgot about it. I took a right turn a couple of years back and started working on the O-320 I have for this project. Several years ago I bought this 700 hour engine from a member here that was properly pickled. I had decided a couple of years ago to tear it down for an inspection and probably leave it apart (with the cam in preservative) and so I started volunteering with the local I.A. Long story short I have been working for him for two years ( as a paid employee) and after another year I will take my A&P test. I have purchased two hangers since then and a Cessna 182 straight tail (great airplane and my regular flyer) and just purchased a Piper Apache (runs but a project) for my A&P doctorate and to help empty the bank account further. Soooo the L21 clone is on the back burner for now. I have rebuilt several engines in the past year but mine is still on the bench in the garage. Go figure. That's the current status of this thread and my build.

[Steve Pierce]

Sounds like a lot of working A&Ps.

[Flying_Fin]

Well I have researched SC.org, google, etc. etc. and decided to start a light wing building thread to try and get some of my questions answered. Many of the threads I followed ended without conclusion. IE whatever happened to the carbon fiber wing build? Did it fly? How much did it weigh? I don't really need the answer to that, it was just an example of how some of the threads went along and then no "ribbons on it" so to speak.

I'm attempting a 1320# gross weight super cub build based on a 1977 totally bare fuse I have. I have built tail pieces (six) from scratch. I have a box of "schneider" stamped ribs (3 piece type for the main wings). Control surfaces will be scratch built. So my parameters are safety, and lite, lite, lite. At this point I'm mainly interested in conventional construction, not carbon fiber etc. I am of course planning the usual "lightning" methods. No electrical at all, 6" wheels (looking for cheap wheels), single puck (I have the cleaveland calipers), bungees, no interior, No rear seat (if thats what it takes), narrow deck o-320 (I have firewall forward <300# measured).

The wing: Like the tail this will have to be mostly scratch built. I want to base it on the PA-18 with flaps. I'm not interested in speed so minimal ribs would be fine. I'm think 13 ribs/wing. I have purchased D&E front and rear spar blanks.

Questions:
1. I would like to make the leading edge skins (other than tank area that would be .025) from .016 2024 T6. Dis regarding dents etc. would this be strong enough? .020 adds about 4# to leading edge. 8# if trailing edge requires thicker. This question comes because of a comment Mike made concernig 2024 being stronger than stock 3003.

2. How about .016 for the trailing edge? To weak for supporting flap hanger/hinges? If to weak maybe double up for a few inches in that area?

3. The D&E wing uses a heavy sheet of aluminum under the tank bay as a "drag strut?" to replace the tube going through the fuel tank. Actually in stock wing it's two tubes since there is the "welded to the tank" tube and the actual drag strut tube passing through it. What does everyone think about the concept both strength and weight wise of the torque plate vs drag strut tube? If it wasn't any heavier I would want to incorporate that "torque plate" idea and avoid the more complicated fuel tank construction.

4.Using the extruded compression (D&E) parts is tempting but it looks to me that the original type square tube compression struts would be lighter. Maybe not with all the extra little parts.

5. I am looking at Christian Sturms site for diagrams but find some are not there for the PA-18-150 as per the parts book. Does the Northlanmd CD have all those missing diagrams like 14387, 14389 concerning the LE skins?

Comments? Thanks

My super cub has wooden ribs and wooden wing spars. The total weight is 1108. It has 150 hp. I am not sure how many ribs are in the wings. But they are standard llength.


Sent from my iPhone using SuperCub.Org mobile app

[Flying_Fin]

My super cub has wooden ribs and wooden wing spars. The total weight is 1108. It has 150 hp. I am not sure how many ribs are in the wings. But they are standard llength.


Sent from my iPhone using SuperCub.Org mobile app

The maximum weight is 1800 pounds. It also has 30 gallons of tank space.


Sent from my iPhone using SuperCub.Org mobile app

[rowdy49]

I want to build a STOL Wagabond, but have to keep it a LSA. Can I use a tripacer or colt fuselage if I manufacture all the other parts myself and get it approved. Would also like to get the stall speed down on it if possible. Should wings be made longer and extend fuselage? Open to all suggestions.

[bcone1381]

The shortcut of coming to this forum and asking if you can use a Tirpacer Fuselage seems nice and easy. But this forum is not an authority. let the authority that certifies your aircraft be the authority that answers your question.

The first link below is the FAA document that a builder completes. He checks every box as to whether things were fabricated or assembled by an amateur. Key words to keep in mind.....AMATEUR, FABRICATE, ASSEMBLE. IF you can use a tripacer fuselage and do enough of the other stuff so that 51% of the assembly and fabrication tasks are completed by amateur builders who are building education and recreation then I think your ok....but I would check with the FAA...I mean call them on the phone or make an appointment and go see them. I would ask "If I use a tripacer fuselage and 51% of the assembly and fabrication tasks are completed by an amateur, then will it be certified as an EAB experimental aircraft?

https://www.faa.gov/aircraft/gen_av/...syCklistFW.pdf

The first sentence of the Introduction of this FAA document is also foundational.
https://www.faa.gov/aircraft/gen_av/...st_Job_Aid.pdf

[RVBottomly]

^Yes.

The other thing I'd look at is to compare the Pacer fuselage to the Wagabond fuselage drawings. I suspect the Pacer is a bit heavier. If you extend it some, it gets even heavier.

Make the wings longer, and pretty soon you might find an empty weight nearing 1000 pounds--entering Bushmaster territory. That cuts useful load LSA category. So, unless you are really light....

Charlie Aileron built something like that: an extended Wagabond with more horsepower and longer wings. I can't find links to it right now, but it was a beautiful airplane. I can't recall if it was LSA.

[skywagon8a]

I want to build a STOL Wagabond, but have to keep it a LSA. Can I use a tripacer or colt fuselage if I manufacture all the other parts myself and get it approved. Would also like to get the stall speed down on it if possible. Should wings be made longer and extend fuselage? Open to all suggestions.

Subject to the comments in post #233, yes you could reduce the stall speed by increasing the wing span. It would require increasing the tail volume (area) to maintain good stability. This can be accomplished by lengthening the fuselage (weight) or increasing the area of the tail surfaces (less additional weight). The added wing span would not need the same sized material as the inboard section of the wing as the loads carried would be less. This would help in keeping the added weight to a minimum.
This: https://www.eaa62.org/technotes/tail.htm is some reading for a start.

Since we know nothing of your background or experience, a good starting place to go for information would be the EAA. https://eaa.org/eaa

[qsmx440]

Well another update: The supercub clone project has been on hold for several years now. What it started in my life has progressed through that time nicely. A quick recap: I learned to fly in the 70's. I was out of it for a few years and then returned about 15 to 20 years ago. I purchased a Quicksilver "Sprint" ultralight (one of aviation's finest aircraft IMHO). I tried the "putting_it-together-taking -it apart" routine for two times and discovered this to be completely impractical and so that led to the purchase of a $60,000 hangar for an $11,000 airplane. After flying patterns for two years only in the early mornings to avoid any hint of wind I discovered this site and started this project. Fast forward a few years and working on this project led to a connection with the local IA and a job offer for part time work. 6 months later I started keeping a log book and the goal was to get my A&P. After about 5 years the FISDO rep signed me off for taking the three written tests and two weeks ago I took the Airframe, Powerplant, and last the General written tests at a testing center over a period of three days. I averaged 88% on the first two and 87% on the general tests all with self study using the Gleim system. All that's left on this is the oral/practical A&P test and I hope to take that in January 2021. Along the way I switched out the first hangar for three others, acquired a Cessna 182 straight tail and a Piper Apache twin. All effort now is on completing the A&P. The supercub project is down the road a ways at this point with all the other aviation interests. This morning I read through this build log and it is long and boring I guess and I may condense the whole thing for easier reading with less detail. I need to re-import pictures of making the empenage (all of the tail pieces) I think I am still dedicated to doing more on this as my confidence level is much higher with my work experience BUT there is a lot going on and I have flying aircraft so we shall see. No matter what, this has been a wonderful experience that has led to totally unexpected results.

[RVBottomly]

I had been wondering what was going on in your life. You have been busy! Congrats on your progress on an A&P!

I go back and read this thread from time to time. It has a lot of useful info in it.

[aecub]

I may condense the whole thing for easier reading with less detail.

You have some unique stuff in here, don't throw anything away.

[Sikorsky]

I'm not sure I'd want to pound this on gravel bars but a 21 pound wing...

https://www.youtube.com/watch?v=hp7JcmwKQcU

Sik

[courierguy]

I THINK the wing (ea.) on my Rans S-7S weighs 78 pounds, that number sticks in my head for some reason, maybe it's 87 pounds, something like that. 2700 hours later of lots of off airport and nothing has moved.

The video linked to above, that kid is sharp! He has some background help though, judging from the planes and big hangar shown briefly in one of his clips, he's not without prior aviation experience in some fashion.