Sometimes when I patch a hole in my covering, the patch does not stay stuck to the original covering after it is cooled off.
Why would this happen?

This doesn't happen all the time, but when it does I've resorted to applying a thin bead of CA around the edge of the patch. this seems to work OK, but it is a bit ugly....(and still leaves the mystery of why it happens)

Do I need to prep the surface prior to putting the patch on? I always clean the area with rubbing alcohol/cotton swabs prior to patching... is this good enough?

I figure the adhesive on the monkote is not activating so I try to turn up the heat a little on my iron, but then it tends to melt the covering...

any ideas?

You need to clean it good before you put a patch on. Any oil film makes it not stick. I clean it good with alcohol before I patch and they stick pretty good. Get the better alcohol and it works better. Just get a sprayer and clean it good, then patch.

Pardon my ignorance, but what is "the better alcohol"???

Can I get this at my LHS?

Thanks

I always keep the good stuff locked up where the in-laws can't find it.

Just clean with isopropal alcohol which is commonly sold at the hardware store. Repeat at least three times with a clean cloth. The slightest oil film will prevent the patch from sticking.

Tom

Try some Denatured Alcohol to clean the area... Try the Monokote trim sheets too, then you don't even have to iron it. Make sure patches are an oval...That way there are no corners to peel up.

The covering needs to be cleaned with alcohol before you try to apply your patch.

I do that next time. Thanks

Good idea. I cut my last few patches out of white monokote and shaped them to look like bird poop.

I figure that my planes aren't all that aesthetically pleasing anyway (built soley for flight-not good looks), so this just makes it a little more fun!