The Barn Find Build

[Eric Page]

Eric, just curious why you didn't just wrap the patch material over the edge and onto the front finished side? It seems it would make a stronger, easier applied patch. Admittedly it would require a lot more sanding to bring it to finished dimensions, but a good old Dremel tool would make fast work of it.

I thought about it, but to make the new material flush with the original surface would have meant grinding/sanding virtually all of it away, so I didn't think it made any sense. Given the rough treatment I gave it getting the hotel key cards off, I'm pretty confident that the repairs aren't going to crack off, and once they're trimmed down to final size they'll be quite small areas anyway. Fingers crossed.

---

My second attempt with the repair putty turned out the same as the first, despite putting double the recommended amount of catalyst in it. I'm suspicious that all the milled glass I've been putting in it is somehow impeding the cure. Whatever the cause, I've got another mess to clean up.

I think my next step is going to be a test run with just catalyzed putty with no additives, just to see if it will cure properly. If it does, I'll have a way forward with materials I have on hand, and if it doesn't, I'll be pretty sure that the putty has gone bad. I'll get that mixed up this evening and hopefully find a solid mass in the morning.

What a ridiculous waste of time...

[alexM]

Weird. The milled fibers would not impede the cure. But good resin is like good food. The good stuff has a shelf life.

Doubling the MEKP should have kicked it off for sure. And you did use MEKP and not MEK, right? Not same same.
It actually should have got hot or even started smoking. The good news is that you can clean that mess up easily with some acetone and a rag.

You were on the right path to lay up against the credit card (next time put a layer of clear packing tape on it).

[Eric Page]

Weird. The milled fibers would not impede the cure. But good resin is like good food. The good stuff has a shelf life.

Huh. No idea if Total Boat sells the good stuff, but maybe it has gone bad. It's been in my garage for 2+ years.

Doubling the MEKP should have kicked it off for sure. And you did use MEKP and not MEK, right?

That's what I figured, but my experience with this stuff is nil. Yes, I used the little squeeze bottle of stuff that came with the putty. Pretty sure it says MEKP on the front.

The good news is that you can clean that mess up easily with some acetone and a rag.

Yeah, it wasn't too bad. Worst part is getting the uncured putty out of the weave of the mat/epoxy layup.

...next time put a layer of clear packing tape on it

You'd think I'd know that, given that I've watched Mike Patey build two or three airplanes with foam, packing tape, carbon fiber and epoxy.

---

I made a test coupon by mixing 5g of putty with 3 drops of MEKP (now up to 4x the recommended amount) and smearing it on a sheet of paper. That's sitting on top of the space heater that warms my garage. I'll know tomorrow if I need to order new material.

IMG_2622.jpg

[Eric Page]

The test coupon cured fine, although slowly, so I think the putty is probably getting old. Anyway, I think I'm safe to mix up what would normally be a really hot batch of the stuff and get the seat pan edge repairs finished.

The test coupon did cure, but it's fairly brittle with no structure inside it, so I'm worried about using it to mend the edges where there are over-cuts. I fear it will crack off with any significant pressure.

Alex, is there a better way to fix those areas, short of grinding them back and building out new material with the mat and epoxy, like I did in the other two spots?

[Eric Page]

My third attempt with the polyester repair putty was another failure. I mixed it with 4x the specified catalyst and it still didn't cure, so I threw the can away, cleaned up the mess again and moved to plan B.

This time I prepared about 5g of Poly Epoxy, then mixed in enough milled glass to make a thick paste. I applied that in the now familiar way, set up the heater and crossed my fingers.

This morning, success! Everything finally cured rock hard, without the slightest hint of stickiness.

IMG_2625.jpg IMG_2626.jpg IMG_2627.jpg

I somehow missed patching one spot, so I added the fiberglass mat yesterday, and this morning I made more Poly Epoxy paste and did what will hopefully be my last patch job on the seat pan.

IMG_2628.jpg

Next step will be to remove most of the added material to shape the edges of the patches to the right profile, sand them down flush with the top surface of the seat pan, and probably do a little fill-and-sand with Smurf poo. Then I can mist some paint over the whole ugly mess and pretend that it never happened.

Did I mention that my that my fiberglass wingtips are butchered too?

[Jerrytex]

I went through the same thing with my seat pan. I added fiberglass to several areas where it was cut too short and one area had a crack. A real PITA....I feel your pain!

I found some paint that worked very well and it matched the gel coat color so I was able to touch up without having to paint the whole pan.

https://www.homedepot.com/p/Rust-Ole...1830/202056394

It's dries shiny and smooth.

[Eric Page]

Thanks, Jerry. I couldn't find the appliance paint at my local Home Depot, but I got some other Rustoleum gloss white that looks fine too. More on that later...

---

I made good progress on the seat pan today. All of the fiberglass repairs are trimmed and sanded.

IMG_2630.jpg IMG_2632.jpg IMG_2634.jpg IMG_2636.jpg IMG_2637.jpg IMG_2638.jpg IMG_2639.jpg

It's still far from perfect, but I've stabilized all of the places that were likely to create cracks and made it look good enough to satisfy me. I added a coat of white paint to cover the repairs, but that's going to need some sanding and re-spray because I have zero painting skills and caused several runs.

IMG_2640.jpg

[Eric Page]

Got the paint runs on the seat pan sanded down and repainted. Still not perfect, but good enough. I was standing there feeling smug about the accomplishment when I looked to my right and saw these items sitting on the shelf...

IMG_2644.jpg

Now I get to cut up my freshly painted seat pan!

[alexM]

I hate when that happens!

[Geek]

........Now I get to cut up my freshly painted seat pan!

But the bright side is that you get to do the cutting and not the other guy!!!