New to the USA, best products and advice

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#1

Hi guys,

Just stumbled over this forum-boy have I been missing out!!

I recently moved to the USA from Australia and have a job in Motorsport building a heap of cool stuff for a new race car. The current car is all GRP and from what I can see is a choppy gun special so heavy and weak. My plan is to make as many parts as possible out of carbon, e-glass and epoxy.

Now, the facility has a relationship with Fiber Glast Developments so I have been using their 2000 epoxy system but not too happy with it. What would you guys recommend for a top quality epoxy to be used in lightly stressed race car body panels? I have mainly used SP Gurit products in the past and am very tempted to go down that path but interested in alternatives.

2ndly, I’m making some parts via press mold and vacuum to ensure both sides are shiny, however I still seem to get a lot of pinholes which sucks as both sides need to be clear coated. Am I sucking out too much resin or is the resin of too higher viscosity?

Cheers, Jason.

#2

Check out Pro-Set 117LV for infusion and Pro-Set 125 or West System 105 for hand layup all made by Gougeon brothers as an alternative to the Gurit products.

#3

My favorite resin is MGS L285. It’s incredible stuff for hand layups, press molding, and bladder molding. It’s also one of the more expensive epoxies out there but way worth it.

The pin hole problem with press molding is often from air trapped within the tows of the carbon. When pressure is applied the air migrates to the areas of lower pressure…right at the weave intersections. I could get perfect hand layups without pinholes and then have pinholes once the press was used. The key to resolving this problem was to make sure that there was enough resin on the face of the tool and to make sure the the fabric with adequately saturated. How have you been saturating the fabric? Pre-wetting? Wetting in the mold?

You can get pinholes with vacuum bagging for the same reasons. Also make sure that you use a perf-ply to prevent the bleeder material from wicking the resin out of the weave intersections. On thinner laminates the bleeder will pull the resin out via capillary flow leaving lots of voids. You will often see large discrepancies between the laminate thickness and the weight of the resin in the part which signals porosity problem.

#4

In this situation there is no vacuum stack on the fabric, I started to put p ply and bleeder either side of the fabric to try and pool the resin which seemed to help and yes, I try wetting out the table and mold as best I can (wet out on the table/mold)

Another reason for the pin holes could be because I’m using the carbon Kevlar hybrid crap because the boss likes pretty colors to show potential customers.

#5

Gurit has facilities in the US and Canada, not too far from you. You will have no problem sourcing from them. Fibreglast is a rip off

Also Northern Composites is a really good supplier: www.nfgsales.com

#6

First define what you are looking for in the epoxy used:

Tg
Viscosity
Geltime

These are the main factors. See which epoxy matches your demands. West / Proset, Gurit, MAS, System Three, all suppliers you could look into.