Avid C HH wing build 101

[3CW 3]

Thank you very much for your reply. I Googled Jo bolts and I guess and would have to buy the whole shebang tool and all for 2 rivets. Did you buy the kit? I saw $490, rivets were about $2.50 apiece.

Wyatt

[flywise 169]

Thank you very much for your reply. I Googled Jo bolts and I guess and would have to buy the whole shebang tool and all for 2 rivets. Did you buy the kit? I saw $490, rivets were about $2.50 apiece.

Wyatt

Hey Wyatt, just get the correct size  Jo bolts...you can install using a couple wrenches / pliers...no need for the tool (no space anyhow)

Hope that helps

[3CW 3]

Who do you deal with to get those Jo bolts? I looked at Hanson Rivet, but didn’t see a contact number. I have no idea how to cross reference a SS43FS rivet.

[flywise 169]

Who do you deal with to get those Jo bolts? I looked at Hanson Rivet, but didn’t see a contact number. I have no idea how to cross reference a SS43FS rivet.

You can try these guys

https://trsaero.com/monogramaerospace/products/blind-bolts/visu-lok/

The visu-lock is easiest to install without special tool as the threaded rod section has a flat allowing you to install a wrench so as to turn it ...

You will see the strength on the above website....make sure they are not too strong as the aluminum spar is relatively soft and might deform when you install a too tough lockbolt

The SS43FS rivet is a stainless steel and all I found is a quote from Dholly, see below:

" the first number after the material code (i.e., SS=Stainless Steel) indicates the diameter of rivet in 32nds of an inch (i.e., 4=4/32" or 1/8") and 2nd number indicates the length of the rivet in 1/16ths of an inch (ie., 3=3/16").
Therefore, SS43FS would be a 1/8"D x 3/16"L Stainless Steel rivet. Not sure if FS refers to head type, but I suspect using a standard round or universal..."

Now regarding the strength of a 1/8"D x 3/16"L Stainless Steel rivet, I found a company providing aircraft grade ss pop rivets with all the data (it is mostly in mm so you will have to translate into inches). See page 18 onwards for SS pop rivets.

https://m.europages.com/filestore/gallery/df/f/19339320_b8fe5d0d.pdf

 

Also note that the Jo bolt system can have different names like "Jo-bolts, Visu-lok®, Composi-Lok®, OSI Bolt®, and Radial- Lok® fasteners use the drive nut concept and are composed of a nut, sleeve, and a draw bolt

Here a little write up for you:

http://www.flight-mechanic.com/structural-fasteners-special-purpose-fasteners-blind-bolts/

 

[3CW 3]

Fly wise, you’re an engineer aren’t you! I have a call in to Peerless Aerospace for Visu-look fasteners. Hopefully they’ll have a cross-reference the rivot. Still waiting to here back. Got their name from TriMas who makes them. Thanks!

Has anyone ever dissected a fiberglass fuel tank, 14gal? The tank end which butts to the fuselage needs some profiling work for a good tight fit. One is sunken in the middle where I would need to build up or take down the corners. The other is a good 1/4” out of square. How thick are the ends? Can I sand them to fit? I’m guessing they are an 1” thick.

[Allen Sutphin 705]

When I removed my original fiberglass tank, I cut it apart just to see what was inside. Ethanol does cause separation of the layers of glass and dissolves the resin. So I don't trust fiberglass tanks anymore after what I seen. I understand the new tanks are ethanol proof, but I am a tad gunshy now. And I am not sold on the plastic tanks either but other than having a metal one made, that's all there is to choose from. The plastic tanks contract and expand a smidge with the temps and can cause a seep at the fittings in certain conditions. Best to check the tightness of the fittings now and then to avoid a seep. I mounted my wing tank so it is not rigid to the spars, it is kind of sandwiched between straps so it can flex a bit.  My opinion it that a properly made welded alum tank will not leak if it is not installed rigid. But I don't know much about Avid construction. I just assumed it was similar to the Kitfox. And they are not as thick as one would think so I'd be careful sanding a fiberglass tank unless it was just to smooth a bump of some minor imperfection.

Edited 15 Feb 2019 by Allen Sutphin

[3CW 3]

Hey fly wise! Just heard from Dave at TriMas. Evidentially, they do not make a fastener 1/8” dia. 5/32” is the smallest. There’s got to be a way to pop this rivet! Anybody who has ever built an Avid has run into this. How the hell is it done?

[1avidflyer 1983]

If you take a piece of 1/8" brake line about 3/4" long, can you put it on the tail of the rivet and grab the remaining part of the tail with the rivet gun?  Basicly making a long nose on the rivet puller.  I've done that before when it was hard to reach a rivet.  JImChuk

[3CW 3]

Need a little advice. I’m ready to install the wing tanks. My original plan is to Hysol them in and use enough to feather the profile to the spars. Afterward they’ll be wrapped with fiberglass. To even the tank surfaces to the butt rib on the fuselage, resin with glass shards will be used. My buddy suggested to use the same to blend in the tanks with the spars. Also could you tell me what’s the best degreaser for glueing. A degreaser came with the kit. I can’t identify it by smell.

Whadda think?

Wyatt

 

Edited 6 Mar 2019 by 3CW
Add photo

[3CW 3]

Hi guys,

I'm ready to glue the trailing edge ribs. Can anyone explain what they’re talking about the clamping of a 3/8” block?

Wyatt

[1avidflyer 1983]

If you go over to section VIII, chapter 2 you will see the block clamped in place in photo R2-1.  As I see it, the purpose of the 3/8" block is to hold that end of the flaperon at the right height where it will come out of the turtle deck.  With the flaperon at the right height, you then line up the rib tail so it lines up with the flaperon hinge.   I'm looking at my MK IV manual, but I imagine the C model manual is the same.  JImChuk

[3CW 3]

Thanks so much for gettin’ back JimChuk!

The manual that came with the kit, just says “Avidflyer”. It simply says, glue ‘em on! Everything in that manual is hand drawn. I am using the Mark IV manual that I downloaded and printed off of the forum. It’s a lot more detailed. The picture, R2-1 isn’t clear on my copy and looking back in here, it’s not clear either. Sure wish I had an original!

Wyatt

[3CW 3]

Hey guys!

We kinda took a different tack and put together the flaperon control and saw what they were talking about in regard to the flaperon bearing. What kind of issues would there be if I raised the flaperon horn up off of the 3/8”? Coming off of the 2” washout to 1 1/4”  has came back to bite me again. By lowering the tip 3/4” and pivoting on the center hinge raises the horn. I don’t like it, but I can cheat it in. Raising the horn would help. In hindsight, 2” washout will help the build, maybe not performance. Should’ve stuck with the instructions.

I also have conflict with the flap horn and the elevator push/pull tube. I guess just a little bend in it to clear. 

Wyatt

[1avidflyer 1983]

Raising the flaperon horn may cause it to hit the turtle deck, and limit your movement.  Just guessing as I'm sitting here.  Something to consider at least and look at.  JImChuk

[3CW 3]

Yeah, kinda figured that. Haven’t even cut out the turtle deck. Didn’t know how much room I had. Must be pretty tight.

Thanks Jim,

Wyatt

[3CW 3]

Hi guys! We’re back to work. Our next step is wrapping the fuel tanks with fiberglass matting. Prior to the wrap I need to smooth and blend the tanks to the spars. What do you use? Bondo? My buddy suggested using the Hysol. Also, when smoothing down the areas where I glued the tail ribs, I noticed a spider crack with tentacles about the size of a silver dollar. Whadda think? Gouge down in the cracks and fill with fiberglass resin?

Wyatt

[wypaul 448]

Raising the flaperon horn may cause it to hit the turtle deck, and limit your movement.  Just guessing as I'm sitting here.  Something to consider at least and look at.  JImChuk

also the F-37A's end up short (flap pushrods).  We ran into this issue with a KF2 that a fellow purchased here.  The solution we used was to reposition the horn on the end of the flaperon.  The horns are built and installed differently on the KF but it would work the same way.  The other possible solution is to build longer blocks F-2 U-joint and then put a bump on the turtle deck.

[wypaul 448]

Hi guys! We’re back to work. Our next step is wrapping the fuel tanks with fiberglass matting. Prior to the wrap I need to smooth and blend the tanks to the spars. What do you use? Bondo? My buddy suggested using the Hysol. Also, when smoothing down the areas where I glued the tail ribs, I noticed a spider crack with tentacles about the size of a silver dollar. Whadda think? Gouge down in the cracks and fill with fiberglass resin?

Wyatts

Wyatt I think that I would not gouge out the glass, but sand with 100grit and then apply the wrap if that covers it.  Also for filling/fairing my choice would be Epoxy resin with micro balloons or second choice bondo. Remember the tank has mold release on it so a good sanding is necessary for proper bonding.

[dholly 718]

I would definitely not use Bondo. Poly Fiber manual says it retains moisture and recommends their 2-part Poly-Fil. I used 2-part epoxy Chrome-A-Lite by Evercoat with micro ballons mixed in.

Edited 22 Sep 2019 by dholly

[3CW 3]

Thanks so much for getting back. We’ll go with the Evercoat. Is there a certain number or grade of the Chrom-A-Lite? I just went down to have a closer look at the spider crack on the fuel tank. It appears to me that the tenicles are on the inside of the tank, but the center point would penetrate the wall and create a leak. Hell, even found another one, but it’s all internal. I sure don’t recall dropping anything on them. They may have been like this since I got them. Nonetheless I do need to make repairs. I lightly sanded the area and the only “dust shadow” that showed was the center point. Pretty certain it would leak there. The fiberglass cloth favors the outside, so the inside is smooth with the heavy side of resin. That’s where the tentacles show up. I do feel compelled to at least gouge and fill with some type of fiberglass resin around the center point. Would you know what type of fiberglass the tanks are made of so I can get a compatible resin. I was told the options are ester, polyester or urethane. The pull sheets simply say, fuel tanks left/right STD. The kit is #504, sold in 1989. Here’s a picture. 

Thanks again for your help,

Wyatt

Edited 23 Sep 2019 by 3CW

[Avid Bart 39]

As far as i can tell, the tanks are made out of normal polyester resin.  They make fuel resistant polyester resin that should work very well to repair the holes in your tanks.

https://www.expresscomposites.com/iso-aoc-774-fuel-resistant-laminating-resin

[3CW 3]

Well damn! As always I’m a day late ‘n dollar short. Got the repairs done yesterday afternoon. Took 2 areas down to paper thin, put in fiber mesh with adhesive on one side, then used this blue 2 part epoxy made by 3M (05885). It was pretty tedious as the wall was 1/8 or less, but I did get down to the cracks. The paper work said it was formulated to be used on most composite substrates such as SMC and fiberglass either a cosmetic filler and or adhesive. When I saw this latest post I called the counter man at the paint department of the auto parts store that recommended it. He said he would make some calls to check the compatibility of the product. I hope I didn’t make a a bad situation worse. I didn’t understand the fiberglassing process, but have an idea now. I’ll find out in the morning if I’ll be starting over with the repairs. 

I drove to this particular place because they carried Evercoat products. This is what he sold me. Would I also use micro balloons? It has kitty hair in it. He couldn’t come up with Chrome-A-Lite.

Wyatt

[wypaul 448]

Hi guys! We’re back to work. Our next step is wrapping the fuel tanks with fiberglass matting. Prior to the wrap I need to smooth and blend the tanks to the spars. What do you use? Bondo? My buddy suggested using the Hysol. Also, when smoothing down the areas where I glued the tail ribs, I noticed a spider crack with tentacles about the size of a silver dollar. Whadda think? Gouge down in the cracks and fill with fiberglass resin?

Wyatt

Wyatt I think that I would not g

[wypaul 448]

The use of micro balloons in Epoxy was for filling/fairing the spar,. Sorry I was not clear in my post.  For the stars in the tank my suggestion was to sand the star and the tank wrap would have been enough to take care of them.  That as also not very clear.  Any body filler product doesn't create a goood structural repair.  Once you sanded the star  using woven cloth cut to the size of a 50 cent piece,wetted with resin then a dollar sized piece wetted with resin and so on until the entire area was filled back to the thickness of the tank.  You can find many good articles on the net about repairing composite structures.

maybe the product that you used will have good adhesion and enough fiberglass in it to be a good enough repair but I would not be comfortable with it.  I would suggest sanding down the body filler to say half of its depth and then using the structural repair method above.  The tanks are made with polyester resin and at this point you will be using the same to wrap the tank so use that to carry out the repairs.  As far as fuel proof resin, no reason to worry about because the tanks are polyester resin and will not stand up to alcohol.  Also be aware there are a couple of types of polyester resin available, waxed /finishing resin and regular laminating resin. Use The laminating resin.

once again sorry my ordinal post was less than clear.  I would find someone in your area that is very familiar with composite manufacturering repair and get some help.

[dholly 718]

Sorry Wyatt, I'm not familiar with the kitty hair stuff you mentioned. I bot the Chrome-A-Lite 839 from my local NAPA auto store several years ago.