I read the How To article on here, and it wasn't basic enough. All I want to do is cut a hatch in the top of my US40 behind the firewall to help installing a different engine mount. I've got a roll of ultra coat, and a TopFlight MonoKote Heat Sealing Tool. Not the tiny trim one, 165W thing. It goes from 0 to 3.5 and I got a couple "socks" for it. Can I just cut a square, put it over the hole, and it will seal to the original UltraCoat around the edges when I get it hot enough? Or do I need glue or something? Do I need a heat gun? I tried running the Iron over some of the wrinkles on my trainer, and it didn't do much. I was probably scared I'd melt something. I know this has to be dirt easy, but I need a bit of confidence here guys. If I can get this to work, maybe I'll try and seal my hinge gaps on the plane! Thanks bunches! - Joe

Hey Joe,

Wow did the Big Ten take a beating this year (I'm originally from Midland and CMU)! Anyway, if your just cutting a hole (let's say 2" sq.) to gain access behind the firewall, you can cut a trim piece with about 1/4"-3/8" overlap and cover no problem. Just tack/seal on side, check the fit (you can always pull and cut a larger trim piece) and tack the remaining sides. You don't need a heat gun, just run the iron over the 'hole' and it will tighten up. Make sure you don't stay in place to long, keep moving, heating, and checking. Let cool to tighten and reapply heat as needed.

Hi JOE! I used to use my MOMs' iron way back when on Monokote. If your plane is used, you need to get it sqeeky clean before you knife into it. I don't think there is a better cleaner than MEK. You can get it at HOME DEPOT. You should be able to install a new mount with out knifing in. The new blind nuts can be fished in by sending 1/16" music wire through your new holes. When the wire shows up in the radio compartment, slide a blind nut over the wire, then bend a sharp 90 in the end of the wire. now all you have to do is pull the wire back to seat the nut. carefully thread a bolt and flat washer into the semi seated nut to finish clamping it in place. Back to MONOKOTE,you want to creep up on the right temp with an unknown covering to get the adhesive to activate, or to get it to shrink. If there is even a trace of oily film on the original covering the patch won't hold. It takes lots of effort, and lots of paper towels to get an old slimy surface ready.

Now you guys keep saying to "tack" it around the edges. Does this mean melt the crap out of it? Use glue? The nice article on here kept saying to tack it, but didn't say what that meant. As for not needing a hatch, I've got to remove the old blind nuts, fill in their holes, then put some thin plywood behind the original firewall to put the new blind nuts into. The new and original blind nut holes overlap just enough to make it a pain... - Joe

JOE!! Why don't you just dowel the old holes from the front? thin ca them in, then drill your new bolt pattern. the old nuts can be worked loose if you really try. Wouldn't you want your DOCTOR to explore all the options before he knifed into you[X(]? Even if you had to cut a hole, try the patch with the lowest heat that it takes to get the edges of the patch to stick, that's what tacking means. Once you have a seal all around, then increase the heat untill your patch shrinks. If it isn't up to your standards, cut the patch out and keep trying till you get it right. You said you got a whole roll? If it won't stick, then it isn't clean enough.

Can I drill new holes and do blind nuts half way across the old doweled in ones? hmmm? This might work! - Joe

WOW ! you got your question out before I could clean up my answer!Yes, I would say that if you can bite into some solid wood you have nothing to fear. The trick will be making the plugs flush with the back side of the plywood, so the blind nuts have an even foot hold. If you have a razor saw, you can slice the dowel precisely the thickness of the plywood. After you push the plug in, then hit it with thinCA. Let the CA dry naturally so it has a chance to soak into as many wood fibers as possible. If you have any odd shaped repair work to do, make a pile of fine saw dust, pack it into any crannys, then slowly wick thinCA in, and get your nostrils away fast! It sets up like concrete, so do as neat a packing job as you can before hitting it with the CA. GOOD LUCK!

Joe, the term "TACK" means to apply the iron tip to a small spot one the covering in order to hold it in place. This way, if it's been tacked down and to feel that it's in the wrong position, you can easily remove and replace it. Once it has been tacked down, and you're satisfied with its placement, go ahead and iron it down completely.

PS no need for glues, there is a heat-activated adhesive on the covering. But do a few test pieces to make sure you have the heat set properly. Too cool won't stick well, and too hot will melt the covering, but you have a pretty broad range in between.

BUT the first thing you have to do is remove the backing from the covering!

Not trying to be wise, you'd be surprised how many people forget to do this first time.
Dennis-

Thanks DBCherry. I didn't know there was a peel off backing on it!! Really! I'm soo glad I waited and posted my "dumb" question on here....! - Joe