Fabric repair advice

[BritishCubBloke]

My wife stuck a tent pole into my fuselage fabric on the right near the tail last weekend. We are still married, just, but it did make a small hole with the flap of fabric still in it. I can get to it from inside via the port side inspection panel, so will patch it from there with some fabric tape.

Anyone got any advice on this and also on achieving a good paint finish? I have paint matchpot, but maybe I need to get an aerosol can made up?

Any advice gratefully received.

Many thanks.

BCB

[StewartB]

BCB,
What kind of paint is on the plane?

http://www.polyfiber.com/techquestions/fabricrepairs/index.htm
SB

[JP]

Most repairs of this type are really easy to take care of. First, I gently wet sand the spot down (320 then 400) until I've scuffed the paint. Then I take a piece of light fabric that I've preshrunk on the picture frame rack and cut out a dollar patch with the pinking shears.

Next, glue in place and let dry. Following that I feather it in with the iron on 225 F. Then I mix up a wee bit of primer and really thin it out.

I set the gun on fairly high atomization and very little fluid and ever so gently shoot a pass of primer on and around the spot. Let it flash off and spray again. Repeat this blending process several times. You can do it with an aerosol airbrush if you so desire.

Next, light sand with some 400-600 and clean the spot with rubbing alcohol followed by a tack cloth.

Next, load up the color and repeat the thinned and scant atomization process, slowly building up a blended coverage. When you are done you'll barely be able to see where the hole was. The pros (note: this is not me) can do the blending so well that you can't spot the repair.

There are many ways to do this but this general method described above seems to produce very nice results. I'm sure others will post their favorite method.

Funny thing--I was scuffing a tail surface down to the primer for a new coat of paint when I discovered a patch whilst sanding. Sure enough, there was a hole in the tail. The patch? Duct tape! The guy blended it in with paint so nicely that you didn't even notice it. Got quite a laugh out of that.

[Crash]

Not that I would ever do this, but the vinyl (sticky back) sheet goods that sign makers use to make signs with nowdays, works great on small holes or cracks. It comes in a lot of colors, or you can spray it to match. It makes a good temporary patch but looks so good that you will not get around to replacing it with the real thing. Take a round object the size of the patch you want. Draw the circle on the paper backing. Cut out with pinking shears, peel and stick. No brush marks, no spray halo to buff out, sticks like crazy and you can't tell it from the real thing unless you look ever so close. Heck, most N numbers are made out of it. Crash

[Steve Pierce]

I carry a roll of vinyl tape just for that purpose.

[Fortysix12]

Crash,

Good advice.

[BritishCubBloke]

Many thanks to all contributors. I shall try and patch it from teh inside and see where I go from there. I may then just try and touch up the cracks with a fine brush. Reasonable?

[Steve Pierce]

The internal patch will serve the purpose. The rest is cosmetic unless there is raw fabric exposed.

[JP]

The vinyl is a great idea. I go to the sign shop and buy "blank" pieces of it to spray with the air tech paint and they then make the lettering, etc. that I need for detailing the airplane. It makes a great deal of sense to spray a couple of blanks in the dominant colors for the little boo-boo's in life that occur.

[Lance]

Suppose someone had a 5x8" hole in the side of the fuselage and was trying to make a repair so that the plane can go to Nolstein. That someone ordered fabric, polybrush, and polyspray to make the repair but did not get the polytak. No time to reorder!

Question is, how to repair it either temporary or permanent?

Could the adhesive backed vinyl be used as a temp patch on a hole that big?

[CptKelly]

Bottomgun,
Dang, 197mph in a 50mph zone? They might put you in the same league with Ossama?

Is "Bottomgun" the opposite of "TopGun"?

Mike

[Ruidoso Ron]

Bottom Gun,
That's what they make hundred mil-an-hour tape for. Come on up!

[ROOTER]

Best advice would be to give Kenny Blaylock, at Specialty Products Aviation in Conway Arkansas. His is the Guru in the lower 48 on the subject. He enjoys helping cub owners.
He did my plane 10 years ago and fabric and paint is still a 10.

Jim N94X

[S2D]

If your paint is dope. You can take a patch (dollar sized or a touch larger) some acetone and a brush. dip the patch in the acetone and stick it over the hole. then lightly work it with your fingers. then take the brush dipped in acetone and lightly keep brushing the patch.it will slowly work its way into the dope. Then finish building it up with dope, sanding often. it is possible to literally make the spot disappear. Hardest part is not letting the acetone drip and run down the fabric.

Bottom Gun-- Same process would work on yours also. but recommend doping (Poly spray) some tapes on over the edges. 2" overlap on the fabric and 1"( or more) on the tapes.

If you have other than dope finish, I would think any good spray adhesive would work for short period, as long as you overlapped wide enough.

[Steve Pierce]

One could polybrush a patch on the inside of the fuselage if he made it quite a bit bigger than the hole.

[Cimarron]

seeing as you also forgot to order rujuv to clean off an area to patch I would suggest calling a few shops around and seeing what they could help you with.

[Jake]

On a bigger scale I am having to replace some tip ribs, what is the recommended procedure for covering from the outboard aileron rib out? I am using ceconite and my plan so far is to sand 4" inboard on, glue my new fabric and incorporate the seam into the outboard aileron rib stich. Does this sound ok? Or do I need another stiched seam?

[Lance]

Well, I have been working out of town quite a bit and have not had time to devote to the cub. The last minute fabric thing ended up being a problem that I created and I could have fixed it well enough for the trip but...

I tried to order a Niagara oil cooler about a week ago to help with the hot temps but she said it was about 4-6 weeks back log. When I came in from out of town Friday I figured I would boil out the old one, stick it back on and head to Wis.. When I took it off I found the outlet was worn down paper thin by being loose in the mount brackett. I tried to braze it and did not like how it turned out. So it was not meant to be.

I have tried to make it to New Holstein since it started but work prevented it. Don't worry I'm still coming. I am just coming in the 180

Cheers, Lance!

[Steve Pierce]

Jake, If that is dope on that Ceconite I would wet sand inboard tape seam on the farthest outboard good rib. When you sand down to the tape's pinked edge peel the tape off and cut your fabric just outboard of that. I think the new Ceconite STC requires a 2" glue joint. Glue your new fabric where your 2" tape was over the rib stitching and finish out the tip. This keeps the fabric inboard of your repair taunt and makes a legal repair. My Stits manual outlines this exact repair. I just got the new Ceconite STC manual and can't remember what it calls for. I would spend the $10-$15 for the manual to make sure the repair is done in accordance with the STC.

[Jake]

Thanks Steve, I have enamel, not dope as the color coats :roll: do I need to do anything different?

[bob turner]

I have to do a large patch tomorrow. AC 43-13 allows for a doped patch, 4" overlap, with 6" surface tape, for grade A or Ceconite. The Ceconite STC now says to see 43-13.

Stits allows a 2" seam with polytak for any size repair, apparently, but I am working with Ceconite, or more correctly, Decathlon process, where Dacron is specified, along with the usual nitrate/butyrate. I have lent or lost all my older procedure manuals.

If I decide not to go with the 4" overlap, the AC is ambiguous about the types of sewn seams to use. It is clear that a baseball stitch can be used, with both edges of fabric turned in 3/8". But it seems to allow an overhand stitch, which I want to interpret as being OK with the patch overlapped by, say, more than an inch, and the stitch simply in the middle of the overlapped area. Common sense says that this, with Super Seam cement, would be as good as the Stits repair, but I'm not really sure of the absolute legality. As I recall, the older Ceconite manuals were a lot more comprehensive than the ones from the new owners of the STC, who are working to eliminate options.

So: anybody have a Ceconite manual from, say, the 1960s, with a fabric repair section? Did Super Seam cement support a repair of less overlap than the one for dope and cotton?

[Steve Pierce]

Bob I will look it up when I get to the shop in the morning. I do know all the adhesives worked better on cotton than they do on dacron. Will look in my old procedure manuals and compare to the new and post tomorrow.

[Steve Pierce]

The old procedures manual I have refers to the 43.13-1A sec 3. The new manual I have says doped in repairs on A/C with a VNE of less than 150 mph must be less than 16". 2" overlap if less than 8" repair, 4" overlap if over 8". They also specify using the New Super Seam. It is stronger than the old and I was told by the Poly Fiber tech guy that it is the same as Poly Tac. Poly Fiber is 1" overlap up to 8" repair and 2" overlap on a repair over 8". They also talk about repairs such as a whole wing tip where you glue a 2" over lap over a rib and to the tip. I have done a lot of these repairs from rib bay to rib bay with no problems with either system. About a year ago I took some of the Air Tec glue and glued a 2" over lap joint, let it dry over night and clamped the fabric to a test fixture. The fabric came apart before the glue joint did. I also learned that a glue joint on cotton is almost twice as strong as the same joint on Dacron.

[bob turner]

Thanks, Steve. I recall hearing that Poly Tak and Super Seam were in fact the same, although the markings on the can appear to determine legal usage. I have had great success with Poly Tak over the years, but right now am working on someone else's aircraft, and must cross the Is and dot the ts.

Sounds like I am stuck with the 4" overlap, 6" tape. It will never let loose! Hopefully Goldenbaum will certify the 2" repair for his Ceconite process with New Super Seam.

By the by, 43-13 says explicitly that the 4" + 6" scheme is good for any speed, any size, any fabric. Can't go wrong there, I guess.

[Steve Pierce]

I wish they would combine the fabrics and tapes too. They all come off the same roll and get stamped either one as told to me by their own employees. I keep a roll of fabric and rolls of tape and it is crazy to have to stock both. God forbid I would use nitrate/butyrate on Poly Fiber dacron.

[bob turner]

With the possible exception of a quality control inspection and sometimes thread count, even the homebuilder dacron is identical to Stits, Ceconite, etc. Of some interest is the Bellanca Citabria and Decathlon service manuals, which specify Dacron, not Ceconite or Stits. The real difference used to be price, where the uncertified stuff was half the price. Now that one entity owns all the STCs, the difference is roughly 4:1.

The patch is done; I used the 43-13 technique. Stits tells me that they are working on the 2" overlap for Ceconite, since the cement is now the same. My experimental friends tell me that a 1" seam and 2" tape is bulletproof on such things as Christen Eagles.