Epoxy compatible - tooling gelcoat

General Composites Discussions Composites Talk
#1

Does anyone know where (in the USA or Canada) I can purchase a small qty of epoxy compatible VE gel coat (1 gallon)? I prefer a vinyl ester gel coat over an epoxy surface coat for reasons that I’ve read about on this forum (epoxy surface coat doesn’t polish up as nicely as VE/PE gel coat nor is it as easy to repair plus I’ve heard its dangerous to spray epoxy).

So far the only options I’ve been able to find are:

  1. GC3-130 (Axson Technologies) - sprayable vinylester tooling gelcoat, compatible with epoxy laminating systems. The problem with this particular gel coat is simply that there is only one Axson distributor in all of the USA & Canada (BMB Solutions Composites - Canada) and they tell me that they don’t sell that particular gel coat.

  2. Stypol 945YJ071 (CCP Composites) - sprayabble vinylesster tooling gelcoat. Although the data sheet doesn’t specifically say this gelcoat is compatible with epoxy laminating systems I have to assume it is because of the fact that it IS vinylester. I spoke to CCP Composites tech support and they said it “should be comparable” but recommended I test first. The problem with this particular gel coat is that Composites One is the only USA distributor and they won’t sell it to me because I’m “not a large business”… I called a local composites shop that buys from Composites One to see if they could source a gallon for me but was told I would need to buy 5 gallons (yikes! don’t really want to spend $500 on 5 gals of gelcoat when I only need a bit over a 1/2 gal).

  3. APG 1750 S - (Axson Technologies) - sprayable styrene free tooling gelcoat. The data sheet for this gelcoat does indeed say its compatible with epoxy laminating systems . Does anyone have any experience with this gelcoat (laminating epoxy over it)?

  4. My last ditch option is to use standard PE Tooling gelcoat, then add a tie coat of VE resin, then bulk up w epoxy. The idea being the epoxy laminates will bond well to the VE tie coat.

Any ideas where option #1 or #2 can be sourced in the USA/Canada OR confirmation that option # 3 or #4 will work would be much appreciated.

#2

Use any good VE tooling gelcoat, laminate a layer of low tex CSM behind it with vinylester, let cure properly, sand well, and laminate epoxy behind it. By far the easiest solution.

#3

I know its not in the US but maybe you could call these guys and ask for advice for local products - its an epoxy compatable polyester gelcoat which is supposed to have better clarity than epoxy gels, so would that be of interest?
http://www.easycomposites.co.uk/products/polyester-gelcoat/epoxy-bonding-polyester-gelcoat-clear.aspx

#4

Herman - thanks as always for the help! My biggest problem is finding a VE gelcoat here in the states (I dont know why more composites shops dont offer it???). Or did you mean PE gelcoat?

findhan - Thanks… The gelcoat you provided a link for sounds VERY similar to the APG 1750 S gelcoat (click the link below to see the TDS).

http://www.axson-na.com/TDSs/TDS%20-%20APG%201750%20S%20US%20Rev%2000.pdf

This AM I spoke to Alex (technical rep) at BNB Solutions Composites in Canada and he is confident the APG 1750 S will bond very well with epoxy laminating resins when applied directly on top of the gelcoat (he says they’ve tested this). He recommends waiting to apply the epoxy/back up reinforcements just long enough for the gelcoat to cure but yet remain slighly tacky (the TDS says 75-115 min).

#5

So I’m considering taking the PE/VE tooling gelcoat + epoxy laminated reinforcement stack approach. I’m considering going with the same Axson system mentioned in the thread’s first post (APG 1750 S) because Adtech distributes that now after being bought out by Axson. This means I can pick up a gallon or two of their Adtech 820 laminating resin to use as the backing, while also getting a small and easy gallon of the Axson gelcoat in the same order.

My main concern is dimensional stability over the long run because this is a fairly large and oddly shaped part that would be hurt considerably by any shrinkage. So I have two questions

  1. Do you think I’d be good with the Axson + Adtech solution, simply by following Herman’s (always great!) advice of just waiting for the VE component + veil to fully cure and then laminating epoxy to the back of it?
  2. Does anyone have any other VE tooling gel coats that they could suggest that can be easily sourced in small quantities in the US? I can really only find PE gelcoats through the normal online retail sales channel. Scott Bader has a Crystic 15 system that I’m considering getting, but they don’t sell any laminating systems so I’d lose on shipping.

Thanks for the suggestions!

edit:

Or, some other options that I’ve been considering:
3) Still finding a way to get my hands on a good VE tooling gelcoat but then backing it with an easy-to-get VE laminating system (Hydrex 100 33350 from express composites)
4) Just going ahead and using PE gelcoat instead of VE one. What are the real benefits in a gelcoat of using VE, since the shrinkage doesn’t matter quite as much?

I’ve heard that if you’re hand laminating epoxy, it’s still advisable to vacuum bag it to achieve a proper amount of compaction. So is it just advisable, or is it an absolute necessity?

#6

I’m a fan of the Duratec products plenty of options to choose from

#7

Nord rm 3000 tooling resin , everything you ask for and more…

#8

Can this product be bought in the US? Can I ask where you get yours from?

NC42, I didn’t even know Duratec made tooling gelcoats, aside from their additives for other brand’s gelcoats. Which product would you specifically recommend? I can’t find any tooling gelcoats on their product line card (http://duratec1.com/pdf/rightchoice2013digital.pdf)

#9

When you say epoxy compatible, what do you mean? Do you mean a mould that is able to produce epoxy parts? Because you can do this with PE gelcoats if you use a good release system, like Frekote.

#10

Just use the full tooling system polyester with the VE gelcoat. These systems are zero shrinkage so no need to use epoxy.

You can build up the laminate thickness faster and cheaper with CSM and less labour than using cloth$ and epoxie$.

#11

We will be building epoxy parts off of it, but the question was with regards to backing a VE tooling gelcoat with an epoxy laminated FG reinforcement stack.

Any specific tooling system you would recommend? So far I’ve only used the US composites 404 isophthalic PE system and I wasn’t too impressed with it. Saving $ by being able to use CSM is attractive as well but I generally find wetting out woven cloths and then applying them to the mold surface (+ extra wetting out) is much less labor intensive so the cost savings are reduced. This is a production mold for a fairly expensive and important part so saving a hundred bucks isn’t as important to us as having a very well built mold (but I still appreciate the suggestions!)

#12

Smooth On offers an excellent"gelcoat" called epoxacoat. My molds are made with it and are excellent. It is epoxy, I wet sanded to 2000, and make my semi perm application. Use the sealant first! The 700NC dries to a decent gloss. Parts come out perfect. Excellent product. Also, Fiberglass Florida offers a fantastic laminating epoxy for much less than us comp. You’ll find what I’ve said here to be a very reliable way to do business.

#13

Is the Smooth on to be applied as a first layer over the plug like a gelcoat or is it to be applied to the finished mold surface?

#14

Herman, why not just let the VE gel coat cure, then lay up with epoxy and laminates?

I’m talking about this type of epoxy primer -
http://www.autobodytoolmart.com/transtar-2k-epoxy-primersealer-white-dtm-quart-6104-p-25189.aspx?gclid=CPL56r_PhcECFStgMgoddksA3g

#15

Over your plug. Make sure it’s perfect. There’s a video on YouTube.

#16

Just went over to Reynolds (our local smooth on distributor) and checked out the epoxacoat system. Looks like a good one. I appreciate the suggestion. Do you back it with their epoxamite laminating system?

#17

be aware that it is the resin that will shrink not the fibres, so be careful how much extra wetting out you do. ve gelcoat and a quality pe tooling system is tried and tested and more than adequate for most applications. You can add ATH to your iso resin to make a budget version of low profile tooling.

#18

No. My molds have epoxacoat finishes and us composites laminating resin. However now that I’ve found fiberglass Florida, I’ve changed to their laminating epoxy for hand layup. I use sunrez UV cure vinylester for infusions.

#19

Try Reichhold www.reichhold.com in the us for a suitable tooling system.

#20

Thanks for the suggestion. Sourcing small quantities of these specialty systems was proving to be too difficult so I ended up just going with UScomposites’ polyester tooling gelcoat and their VE laminating system. Once we start to build up a couple of these molds (we’re still prototyping) I’ll probably go ahead and try and order one of the better ones.

For the record, 3M is the prime distributor of Nord Composites’ stuff in the US. They can’t get RM3000, but are able to get RM2000 and something called RM2550 in 5 gallon and drum quantities. The only downside (besides the volume…) is that there is also a pretty significant lead time on them, on the order of a couple of weeks.