Epoxy not that much more than Vinyl Ester

[nothing to lose]

Often Epoxy is said to be allot more expensive, But is it really? A little maybe, but enough to worry about? Not if it makes a better product I think. I'm comparing Epoxy to Vinyl Ester by price and volume here. Not cheap $20 fiberglass resin.

I am not sure it's all that expensive unless I was looking at something else. You get more Epoxy Volume so it SEEMS to be allot more costly buying a gallon, but it's not much if you break it down.

 The cost of Vinyl Ester was $38.50 for a gallon, it has a tiny tube of hardener. You get 1 gallon total volume.

The epoxy's I looked at cost more yes, but reading the fine print you actaully get MORE.

1 gallon of Epoxy uses more than 1 quart of hardener, it says to add the amounts together to figure the volume when mixing. Therefore you get over 5 quarts in volume, and when I divided that price by 5 and multply by 4 it gets really close to the cost of Vinyl Easter. Only $4 a gallon more!

"Epoxy with 3:1 Ratio Medium  Epoxy Hardener, Resin Amount 1 Gallon, Hardener Amount 42.6oz, price $53.00"

That's a volume over 5 quarts, so less than $10.60 quart.

Vinyl Ester cost me $38.50 for 4 quarts total volmue, $9.63 a quart.

The epoxy is only $1 a quart more, or $4 a gallon more.

If your going to use that much resins/epoxies it makes a difference, if you only need 1/2 gallon total none of the above matters cause you won't use it, then the Epoxy costs allot more because you don't need the extra volume anyway.

So for $4 difference the real question is which is better? Epoxy for everything? Epoxy for just rotors? Etc... Or is Vinyl Ester better?

I don't care about the $4, I want the best product for the job.

Is Vinyl Ester or Epoxy best for stators then? I bought Vinyl Ester for mine, but wondering!

[ghurd]

Some epoxy (ebay) shrinks. A LOT.

E-27 Edison base bulbs needed refilled!

The stuff was only 12% of what I have been paying, per total volume.

So all epoxy is not the same.

G-

[vawtman]

Type in epoxy vs vinylester Nothing To Loose itll lead you redrock which did testing not sure how to bring up links.

  How in the crap does one bring up links?

  Im an epoxy fan even if it was double in price.

[wdyasq]

Epoxy can be reasonable or expensive. So can other resins. Normally Vinyl Ester has higher heat rating than Epoxy. Most Epoxies start to soften at about 130F/55C. Most Epoxy FORMULATIONS are more waterproof than polyester.

I can get 'boatbuilding epoxies' for from $50 a gallon to $100 a gallon on one gallon lots. The price goes down with quanity with about $30-35 a gallon about as low as I can get for a real epoxy.

ALL casting of resins should include a LOT of glass fiber. Carbon fiber is electrically conductive and expensive. Resins by themselves have little strength.

IMO, polyester is worthless.

Ron

[DanB]

Yes..

I don't have great experience with it all but I know enough now (the hard way) to know that not all epoxies are equal.  I tried some of the 'cheaper' stuff from shopmaninc.com (same place I buy vinyl ester) and it was very brittle and full of little cracks when it dried.  A whole different animal than the west system stuff I normally use (About $100/gallon)

Vinyl ester is better for stators in my opinion(than epoxy or polyester but I prefer polyester to epoxy for stators) - and for magnet rotors, vinyl ester is far superior to polyester... maybe almost as good as good epoxy.  The vinyl ester doesn't shrink - it seems to stick (better adhesive than polyester) pretty well to steel.

Im sure Ill change my thinking as time goes on but for now my thinking is: West System epoxy is my first choice for casting magnet rotors but it's expensive - vinyl ester is a close second, and epoxy is a poor choice for stators (Because it doesn't stand the tempurature as well and the good stuff is too expensive).

I'm not sure what the cheap epoxy is good for...  I have a couple gallons that I'm afraid to use for anything.  

[nothing to lose]

Ok guys, thanks for clearing that up.

 Certainly if the good Epoxy is $100 a gallon, then that $53 stuff is something different. I geuss it's the cheap stuff we don't want to use that I was looking at.

[nothing to lose]

Thanks DanB

 Looks like I will cast everything in the Vinyl Ester then as I first thought.

You probably saved me some time, money, and lots of problems, THANKS.

When you cast the 12" magnet rotors, about how much resin does that use? I think you have said about 1/2 gallon for the stators, not sure if I ever saw how much for the rotors though.

 

[DanB]

well - it might be fine.  Just the stuff I got didn't work so well the times I've used it.  There are certainly lots of formulations - I could've screwed up somewhere when I used it... who knows.