arg! groove

prkaye · #1 07-26-2008, 04:09 PM

When trimming my windscreen, I started a cut on the wrong side of the tape, and now have a groove near hte bottom corner of the windscreen (photo below). The groove is about half way through the thickness of the plexi. I sanded it out to avoid a crack forming. Now I'm considering options:

1) Do nothing to the plexi, and bring the fiberglass fairing high enough to cover it.

2) Fill it with something. Would have to be something thick enough to stay in the wide groove (if it's not viscous it will just run out). Any recommended products?

Suggestions?

asav8tor · #2 07-26-2008, 04:33 PM

http://www.rplastics.com/weldon4.html

I think most people are going to tell you something you don't want to hear..... that is to start over with a new canopy. The solvent carefully applied with a syringe MIGHT work or it might not.

Good luck.

jsharkey · #3 07-26-2008, 05:30 PM

How long is the groove and where is it?

It looks as if it's at the lower aft edge of a tip-up. Perhaps you can fiberglass over it as part of a tip-up "basket handle" molding.

Jim Sharkey

Mark Burns · #4 07-26-2008, 05:42 PM

Phil,
I'd say you lucked out!
It looks like it's right at the lower part of the roll bar on a slider.
That groove is going to be mostly covered with your epoxy/fiberglass layup.

You might be able to make your layup extend a little more forward than normal to cover it all, and still not look bad.

One thing we say to each other at work is "if you don't screw up every now and then you aren't doing anything"

Mark

prkaye · #5 07-27-2008, 07:29 AM

It is a slider and indeed it is near the lower aft edge of the windscreen (about a half inch above where the skin meets the rollbar). It is on the inside (the side facing the roll-bar). It doesn't matter how it looks, as it is hidden by the rollbar and should eventually by fiberglassed over by the windscreen fairing.

I just want to be sure this doesn't lead to a crack or breakage, which is why I was asking about a product to fill it with. The weldon will be way too runny for this (this is not narrow crack but a relatively wide groove). Any tips for an off-the-shelf product that I could fill that with? Some kind of glue or cement? I won't be fiberglassing that for a long time, because I'm leaving the turtledeck skin and rollbar off permanently until I get wiring and stuff done.

I could also plan my screw spacing so that I "use" part of the groove for a screw hole by drilling through it, and countersinking for a screw... not sure if this would be wise... probably not...

N395V · #6 07-27-2008, 08:13 AM

Replace it with new. If for no other reason it is something you are going to see and remember evry time you walk up to the plane.

szicree · #7 07-27-2008, 09:06 AM

I met a guy a while back who worked for a company that makes all the plexi windows for big aquatic parks and aquariums. To hear him tell it, there's just about nothing they cant fix. You might want to contact someone in the custom aquarium business to see what they know.

prkaye · #8 07-27-2008, 10:28 AM

Quote:

Replace it with new. If for no other reason it is something you are going to see and remember evry time you walk up to the plane.

Again, because of where it is *it won't be visible*. I'm not concerned about the aesthetics of it (since there are none - it will be hidden), I'm concerned about it developing a crack or break here. I'm thinking of filling it with plastic cement just to be on the safe side. Again, this won't be visible after I do the fiberglass fairing.

BillSchlatterer · #9 07-28-2008, 09:50 PM

Not sure about the issue but I think there was an article in Sport Aviation about a guy who repaired a cracked gun turrent plate on a restored B17. Might have been the Silver Overcast.

Anyway, he drilled, grooved, filled, and polished and it came out good as new. Looks like yours is under the fiberglass and won't need a clear filler but this might be one method.

Might look in back issues or maybe someone else has the article/issue handy?

Bill S
7a