chopstrand/ biaxial fibreglass queries

[Lurkin]

Having my first go at fiberglassing, obtained a genuine TOMs bumper which has seen better days.

Noticed these boxes on trademe of mixed chop-strand and biaxial mat which work out pretty damn cheap!

http://www.trademe.co.nz/Members/Listin ... ber=169314

question - is it ok to use biaxial mat with polyster resin? I was planning to use chop-strand, and understand from browsing the web that it may be more appropriate due to being more flexible?

thoughts?

[Grrrrrrr!]

Using polyester with any sort of dry reinforement should be fine, the polyester resin will disolve the binders used to make choppy just fine.

remember to wear gloves and eye protection, and try not to breath too many fumes.

[Akane]

What sort of repairs are you carrying out. Chop strand is very noob proof, good strength.

Get some rollers and brushes and gloves.

For short term exposure I wouldn't worry about a mask unless you really value your health.

[Lurkin]

The bottom splitter has separated at one side due to impact, and is missing a chunk from the lip at the bottom of the bumper. This is the worst damage to repair. Was thinking it could be appropriate to utilize biaxial mat to make the patch across it, then utilize chop- strand to reinforce around it.

Could of cracks other than that - just chop strand those puppies ftw.

However, whats the technique for using rollers/ not using rollers? in some of the areas I will not be able to get a roller in there? Is the rolling process to try and roll the resin into the matt - if this is the case wouldn't it be better to soak the matt in the resin before applying it?

- and the only fiberglass roller Ive seen so far is at bunnings.. it was $15! is there a cheaper option out there?

[Akane]

The reason for rolling your resin is to get the air bubbles (air voids) out of whatever mat you're applying resin on.

And the strongest lay is when you can saturate all the mat you have with the minimal resin. More resin doesn't mean stronger. It means heavier.

$15 is cheap.

It depends how budget you are, I mean I did mine with double bias mat without a roller and it's pretty strong.

The big missing chunks you have to patch it from behind and start bogging with fairing compound. You can probably use auto filler but I won't recommend.

[DeeCee]

i've had a fg roller for 5 years and only used it twice. Dab out bubbles with the paint brush you apply the resin with. Go check nzice for my fibreglass tutorials. $1-2 brush, a bit of resin and chopped matt is all you need to do the repair. its more about the prep work and making sure that everything is secured where you want it to be before applying fg