Fiberglass Problems

[JB608]

After months away from building I decided it was time to return to my CC cobra.
Well last night I glassed the bottom of the hull with somewhat poor results.

:( 1.) I couldn't get the cloth to lay flat in one piece
I had to cut a slit at the bow. Do I need to
cover the slit with cloth ?

2.) When I left it it was pretty well smoothed out
but when I checked it this morning it had a
few wrinkles? (the wood still shows so I assume
it isn't a air bubble)

3.) It lifted at the top edge in two spots can the
glass be cut off and filled with resin?

4.) When sanding if you go through the cloth do
you just cover it with the next coat of resin?

Thanks in advance for any help you can give me.
JB :confused:

[P. Tritle]

JB, Don't panic yet, it's still very early in the process. The beauty of fiberglass is that is is just about infinaitely repairable.

1- Cutting a slit at the bow is normal. Trying to make the cloth conform to that much compound curving just isn't posible. When you make the slit, overlap it 1/2" or so, so you'll have two layers on the "point". If it's too late for that, a "patch" of cloth can be added.

2- If wrinkles do turn out to be air bubbles, simplt cut the cloth away around the edge of the bubble and add a "patch" of cloth over the effected areas.

3-The repair for lifted edges is the same as for the bubbles.

4- When sanding, all you want to do is remove the very top of the lay-up level out and roughen the surface to prep for the next coat of resin. The resin should fill the weave to create the Glass smooth surface, which is where the shine comes from in the end. You definately don't want to sand away the cloth.

Since the bottom will be painted, use it to "learn the ins and outs" so that when you get to the sides and deck where the wood grain will show, the cloth will lay down and contour nicely, and deliver the surface you're looking for. Fiberglassing these wood hulls does take practice, so stick with it, and before you know it, the whole process will get much easier.
PAT

[patmat2350]

I learned a lesson- never trust fiberglass! At least, not until it has set well into it's really tacky stage. I'll lay down a section and then keep after it, wiping and squeegeeing and pushing and prodding, because stubborn little wrinkles and bubbles will just pop up from nowhere… I'll keep revisiting every few minutes for about 45 minutes just to make sure, and that's with my "30 minute" Evercoat epoxy that takes about an hour to really set.

Pat M

[dmb]

patmat2350 hit the nail on the head, “never trust fiberglass!” I had to do exactly the same thing keep coming back and checking every 5- 10 minutes for at least the first hour those dam bubbles just come from nowhere and still after all that the odd one was missed which had to dealt with later.

[P. Tritle]

Pat, I'll second that! After having done a prety good bit of glass work on these hulls it's just so automatic to keep pressing down the boo-boo's till things get good and sticky that I never thought to mention it. Thanks for bringing it up.
PAT

[CaptRon]

Did you guys ever think of vacuum bagging it . Then there would be no air or bubbles. You could do it with a simple shop vac .

[ropanach]

Captron: Have you tried to vacuum bag one yet, I would like to see the results, a thread would be nice, I under stand the consept, and releaving some of the vacuum so you don't crush the boat would be another thing, would like to see this done. LOL

[CaptRon]

ropanach ^^^ before you LOL your self into a state of confusion do some reading.

I have done it it works great. You make mistakes and you learn from them but A perfect finish is worth the few mistake you make. Scale down the instructions below and build some boat hulls.



"Captron: Have you tried to vacuum bag one yet, I would like to see the results, a thread would be nice, I under stand the consept, and releaving some of the vacuum so you don't crush the boat would be another thing, would like to see this done. LOL"

I have nothing to do with this company. I am not saying buy anything there are many other resources out there where you can learn for free. My point is this is possible, practical, and turns out a great product for large and small Hulls.


Http//www.gurudvds.com/site/vipfull.asp

[CaptRon]

http://www.charlesriverrc.org/articles/foam_vac/scobiepuchtler_simplebaggingsys.htm

http://www.fibreglast.com/

some more links you may find useful