Fabric bonding repair

[Esser]

Ok, so a little disheartening at this stage in the game.

Had a friend sit in my plane and the fiberglass seat pan flexed, fell below the doorframe and shot out with enough force that it broke the poly tack bond to the door frame and now I have a fabric wrinkle. I’m wondering what the best way to fix this is. I’m thinking of getting some low viscosity crazy glue and injecting it under neath the fabric. Because it’s at the the door frame I’m thinking I will get some SS door frame covers and put them on with rivets as a secondary mechanical fastening method.

What do you guys think?

[jmodguy]

I’m thinking a 5 min epoxy. Used it to hold some seat upholstery where contact cement had failed.

[aviator79]

Ok, so a little disheartening at this stage in the game.

Had a friend sit in my plane and the fiberglass seat pan flexed, fell below the doorframe and shot out with enough force that it broke the poly tack bond to the door frame and now I have a fabric wrinkle. I’m wondering what the best way to fix this is. I’m thinking of getting some low viscosity crazy glue and injecting it under neath the fabric. Because it’s at the the door frame I’m thinking I will get some SS door frame covers and put them on with rivets as a secondary mechanical fastening method.

What do you guys think?

Do you have a picture? I'm not quite sure I follow how it happened, but the result is the fabric popped off the door frame. If it were me, I'd try using Poly Tak, thinned with MEK to an appropriate consistency instead of krazy glue. krazy glue is a cyanoacrylate that has low strength in shear, which, if I understand, is the failure mode that occurred. PolyTak, on the other hand, is very strong in shear. I'm not familiar with the covering system you used, but one concern might be that there is nowhere for the solvents to evaporate to if you inject adhesive under the existing coatings. They may blister.

The right answer is probably to remove that section of fabric and replace it. Since the fabric is already shrunk, you probably won't get the correct tension by just re-adhering the fabric.

[Esser]

It’s hard to see but the jist is the fabric cameboff the door frame. If I push the fabric back down I can almost get rid of all the wrinkles.

[aviator79]

It’s hard to see but the jist is the fabric cameboff the door frame. If I push the fabric back down I can almost get rid of all the wrinkles.

I'm certainly no expert, but if you can clamp it so the wrinkles come out, you might try to re-adhere that by injecting some thinned poly tak under the fabric. If it doesn't work, I think you're looking at cutting the fabric off under the door and replacing it. Not fun work, but pretty much a weekend project, with a lot of tedious masking and paint gun cleaning.

That's really a bummer, especially this close to seeing her fly. You'll get it fixed though.

edit: I was misinterpreting where the damage is. Still possible to repair I think though.

[aviator79]

Where did the seat pan contact the fabric to pull it off like that?

[PapuaPilot]

Did the bond break loose where it jogs through the door jamb?

If so you might be able to try injecting some thinned PolyTak / MEK through the fabric into the corner using a syringe and needle. While it is still wet clamp a piece of wood or angle iron into the door jamb corner. This should pull the fabric tight. Leave it to dry overnight and see how it turns out.

[efwd]

It seems, from what I understand, Phil is onto the correct option. It is what I would try. I have learned that whenever someone is sitting in the pan, I always stick the screws in and screw them down. I got my pan to slip down once and I had a difficult time dislodging it from under the door frame.
Eddie

[Esser]

Did the bond break loose where it jogs through the door jamb?

If so you might be able to try injecting some thinned PolyTak / MEK through the fabric into the corner using a syringe and needle. While it is still wet clamp a piece of wood or angle iron into the door jamb corner. This should pull the fabric tight. Leave it to dry overnight and see how it turns out.

Phil, this is pretty much exactly what I was thinking. Need to find a decent gauge syringe and needle. I'm thinking I will order the SS door from guards as well to go over the door frame and rivet it in place so that if the repair isn't as strong as the rest, it has a permanent mechanical means to fasten it over the top. I'm also hoping the fabric has a little more shrink left in it if I can't get the wrinkles perfectly out.

Thanks for all your input guys, I appreciate it.

Looks like with all the paper work, inspections, and breaking things, I won't be making it to Osh Kosh in FOXD.

[David47]

I'm with Phil. Use clamping of the angle iron/wood to apply tension to the fabric when you pull it down into the joggle. Just make sure you don't stick the fabric to the iron/wood with the polytak.

[PapuaPilot]

Using the door guards is a good idea, that came to mind after I posted. I didn't screw mine in, I think I just used some RTV and clamped them in over night. Hope this works out for you.

I would be careful about trying to shrink the fabric. It might ruin your paint job. Ask around before you do this.

[aviator79]

I would be careful about trying to shrink the fabric. It might ruin your paint job. Ask around before you do this.

I agree with this. Even if it seems okay at first, there will be residual stress in the top coat that might make it fail sooner. Also, the only way to get more shrink is higher temperature, and you could permanently damage the fabric if your iron thermostat doesn't hold temp dead nuts. If you try it, I would just be prepared for the idea that it may result in having to patch the whole area.

You might also try contacting the covering system manufacturer to see if they can give you any tips on how to repair it.

[Esser]

Did a dry run with clamps and got all the wrinkles out.

Think I’ll try it I make a 1/2x1/2 piece of wood instead of the angle. Haven’t found syringes with gauges of needle the will work yet.

If I can get the fabric like this with the re-polytak, I think it will be alright.

Lesson learned. Bolt your seat in before you let people sit in it!

[aviator79]

It looks like you got this Josh. I know you'll be relieved when the repair is complete. Maybe check with a vet's office or medical supply to find an appropriate syringe.

[PapuaPilot]

Another option for syringes would be a supply store for horses or cattle, but I don't know what size needles you can get there.

It looks like this is going to work. ;)

[Dorsal]

repairing is part of building, looks like you have a solution.
What are the door guards that you refer to?

[efwd]

Hey Dorsal
I believe these door guards are what he is talking about. Not the easiest thing to see but it is the stainless steel edge around the bottom and aft edge of the door frame.
Eddie

[PapuaPilot]

Here is a picture of my door guards. You really want to install these to prevent any damage from happening to the fabric at the door frame bottom.

[jiott]

I used thin aluminum for my door guards. It works fine, but a little scratching where the door latches rub against it.

[Dorsal]

Thanks, I understand now, very helpful.