vacuum bagging with electrial tape

billyboat · Post by **billyboat** » Wed Jun 23, 2004 8:20 pm

I ran my boat into the garage with the vhf antenna up. It shattered the fiberglass at the piont it enters the steel collar at its base. I was upset.

Once I collected my self I decided epoxy and glass might fix it. I took a small strip of biax and wetted it with epoxy. Then I wrapped it in a spiral fashion around the broken area. Finally I wrapped the repaired area with electrial tape. Epoxy spurted out everywhere. I cleaned it up and went home.

The next day off came the tape. It did not bond to the epoxy. The repaired area was faired with a file and wraped with white electrical tape. It looks almost factory and is srong as can be. While filing I noticed a super high percentage of the repaired area was biax tape. Very itchy work. There was very little epoxy left that didn't absorb into the biax.

I think that is why people are crazy about vacuum bagging. Lots of glass and strength and very little resin and wieght. Please correct me if I am wrong.

I hope my idea might save someone from buying a new antenna or am I the only one who forgets to put his antenna down.

Billy

Evan_Gatehouse · Post by **Evan_Gatehouse** » Thu Jun 24, 2004 2:10 am

I have heard of people using heat shrink tape to wrap around round objects to aid in consolidation just like vacuum bagging.

And yes, reduction of excess epoxy and removing voids are the main aims of bagging.

Post by **jacquesmm** » Thu Jun 24, 2004 9:13 am

Correct: we used a similar technique to squeeze resin out of our carbon fiber mast lamination, with shrink wrap.
The shrink wrap did not peel off very easily, we may try again with peel ply under the shrink wrap. The peel ply should absorb some of the excess resin.

fishinfast · Post by **fishinfast** » Thu Jun 24, 2004 4:21 pm

when my Dad and I were building our homebuilt aircraft we would use paper towels to soak up the excess resin. You just have to remember to remove the paper towels before the epoxy sets up. We would also use a stipple roller to draw the excess epoxy from the first layer up in to the second one.

Post by **jacquesmm** » Thu Jun 24, 2004 6:48 pm

I never tried paper towels but why not?
What's a stipple roller?

fishinfast · Post by **fishinfast** » Fri Jun 25, 2004 9:29 am

A stipple roller or epoxy layup roller is a soft, spongy, bumpy roller that helps in working out air bubbles but won't lift the cloth. We get them from an aircraft supply house called Aircraft Spruce and Specialty co. Their web site is aircraftspruce.com. They have all kinds of stuff for fiberglass work. A couple of other things that might work for boat building are the flocked cotton fiber and the milled glass fibers they are used for structural filler like fillets and stuff.

Post by **jacquesmm** » Fri Jun 25, 2004 9:52 am

Thanks. Aircraft Spruce is a good supplier but quite expensive.
I never tried those rollers but will check them out. Right now, I pour or brush the resin and spread with a squeegee.

We sell the milled fibers and other fillers at BoatBuilderCentral.

fishinfast · Post by **fishinfast** » Fri Jun 25, 2004 9:57 am

Your richt on that. It seems that if you put marine on it the price goes up but if you put aircraft on it the price goes up a couple more times. If you try to get it from somewhere else and you tell them it's for an airplane they won't even talk to you anymore. Scared of a lawsuit you know.

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