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Gitting epoxy to adhear to a chinese Cowl

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Gitting epoxy to adhear to a chinese Cowl

Old 08-28-2013, 06:08 AM
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rt3232
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Default Gitting epoxy to adhear to a chinese Cowl

I have a chinese arf cowl that apears to have just a gell coat and one vary layer of lite cloth and just holding it in your hand will crack the gell coat.

So what would be the best thing to wipe the in side down with to get good adheason for adding a layer of 3 oz cloth and a little mat arround the openings.

I am curently using west system's products

cheers Bob T
Old 08-28-2013, 06:32 AM
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Pylonracr
 
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Wipe it down with acetone a few times to get all the mold release off. Sand it well and wipe it down with acetone again. Your West epoxy should work fine.
Old 08-28-2013, 07:08 AM
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Erik Steinbring
 
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Denatured Alcohol will work too. What Pylon described is the same process we use only we use Epo-Grip Model Matrix which is fiber reinforced epoxy to repair and reinforce the thin glass and ABS cowlings it eliminates the need for cloth.
Old 08-28-2013, 07:22 AM
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Thanks guys

I kinda had that in mind, as I have wiped it down twice and just used some 220 wet or dry dry of corse an wiped it down a third time. but this is my first reodo with chinese product, just wanted to make sure my thinking was good.

I have heard about thr model matrix and epo-grip but with luck this will be a one time thing and just wanted to use what I have on hand.

Thanks sgain for you input

Cheers Bob T

Last edited by rt3232; 08-28-2013 at 07:24 AM. Reason: spelling
Old 09-02-2013, 02:56 PM
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If the cowl is PVC it will usually have release agent on it as said, once that is removed you need to really scuff it up, 60 or 80 grit and use epoxy to stick your cloth on it other wise it will peel right off in time, use Zpoxy it stays flexable.
Old 09-10-2013, 04:39 PM
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sensei
 
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Just as a note, medium CA used for repairs along with 4 to 6 oz. fiberglass cloth rubbed in with your fingertip sticks to the 180 grit scuffed surfaces of ABS, PVC and cleaned damaged composite cowlings and wheel pants as good as any epoxy and better than most. Please don't take my word for it, try a repair for yourself. This is not a temporary repair either, it's the real deal, I have been doing this for over 30 years now so try it out, you have nothing to lose.

Bob

Last edited by sensei; 10-11-2013 at 02:34 AM.
Old 10-04-2013, 05:43 AM
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rt3232
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Well just an up date

Cleaned it with acetone, it was so thin the acetone on a rag went through in a coupla spots, skuffed it a bit with 89 grit paper used west system epoxy, 3 oz cloth cut in to triangles got it done and it realy stifined it up added some c/f at the mounting points. onlt added 4 oz total to it.

So now its time to add air control baffles. Any way had my hot glue gun out doing a "honny do" thingy so i put a glob in a damaged cowl and just stucka piece on lite ply in it. next day when I remembered it tried to pull it off, and the ply let go before the hot glue. So I am thinking of using the hot glue to hold the baffles.

any thougth's

Cheers Bob T
Old 10-04-2013, 06:49 AM
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Hot glue should work, but it may be a little heavy. Why not cut the baffles accurately and glue them in with your epoxy. If they fit tightly there will be very little glue needed. Just make sure there are no gaps between the cowl and the baffle.
Old 10-04-2013, 04:29 PM
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rt3232
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yap that is what I have been doing for 30 years, but do to viberation and a bump hear and there they partiality come loose, so at some point I end up redoing them. So I was looking for glue with a little more flexablity. I know there is an epoxy like that but I have only been able to find it in Qt size and it's coast is to much for the shelf life you get as I only build about 1 bird every other year and some times longer than that. Will have to put a coupla of rowes on a piece of scrap and see just how much weight it wold be.


Thanks for your thougth's


Cheers Bob T
Old 10-10-2013, 12:02 PM
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If hot glue works with heat, will the engine heat in the cowl soften the hot glue??

I use a product called Lexel. It is a clear calking that smells like the old plastic model glue. It is somewhat pliable, but very durable and vibration proof.

Steve
Old 10-10-2013, 07:19 PM
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Just to add more confusion to this glue controversy My buddy has glassed abs cowls with pvc cement and glass cloth. He uses the pipe glue from the hardware store.
Old 10-20-2013, 04:15 PM
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rt3232
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Hi guys

A little up date, first it is an eopxy/glass cowl, so after doind a little more experimenting with the hot glue and then heating with my hot air gun and an old coverite temp gage, could not get the glue to let go till up to about 300 degs and none of my cowls have ever get more than just warm to the tuch. So I have gone and done it with the hot glue, so now will have to waight till I can get this bird in the air, and with the weather what it is it may be next spring.

Cheers and thanks for all of your comments and Idea's

Cheers Bob T

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