Epoxy Flow Coat

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#1

Hi Guys,

I have been trying to make a fiberglass mold of a cowl I carved and am struggling a bit. I’m using polyester resin so I could use the gel coat for a nice surface. I had some issues with separation so after repairing my plug I am ready to try it again, however I’m tired of working in the garage (wife hates the smell).

So, I would like to use the epoxy resin I purchased from US Composites this time. Not being able to use my polyester gel coat, what do you guys recommend I use for a flow coat?

Thanks for your advise,

Dust

#2

There are epoxy surface coats.

what is it that you mean by flow coat? Just a beauty coat?

#3

Ya, I was using the flow coat to make sure I got coverage in all the tight areas and to give it a nice finish.

Surface coat? I’ll go google it. Thanks!

Dust

#4

Will your surface be painted or are you going to go with the carbon fiber print? if so, are you hand laying it, vacuum bagging or resin infusion?

If you are hand laying it, I have brushed on thin coat and degassed it to remove micro bubbles and let it get to a tack applied another coat same procedure. Once you get it to a desired thickness which will aide you at the end lay your part and let it cure.

Some finishing will probably be in order to get the desired finish you want, remember you applied several coats at the beginning, buff them to get the finish you want. Be care not to sand/buff to much. You should get a really good part and a great shine!:cool:

#5

Thanks Soja,

Yes it will be painted. I’m actually making a fiberglass mold first, then from it, a fiberglass part which I will then paint.

Is there a surface coat you prefer to use?

#6

I see some from freeman:
http://www.freemansupply.com/RoomTemperatureEpo.htm

haven’t used epoxy surface coat for parts. I have used it a good bit for tooling. The tooling stuff shines out nice but, can crack or chip. I see they have a hydrophobic and impact resistant variants… could be interesting. Surely some one here has experience with these chemicals?

#7

If everything is epoxy based, then yah you should have no problems with sanding and recoating.

#8

Not sure what you mean by “surface or flow coat” but when I am making epoxy molds, the first layer I brush on (Which I consider my “gel coat”) I use a thicker epoxy, thickened even more with high density filler and then add red dye. I usually do 10-15% high density filler and that seems to work well and it shines up good and is strong and can be repaired.

#9

I use the west system 105 with 207 hardener which works well for this.

Some laminating epoxies are not so good with using as a brushed surface coat since they are much thinner and just run away.

Use a prepsol/wax and grease remover before coating since epoxies are very sensitive to surface contamination and can fisheye. Usually due to oil in your compressed air.