Fiberglass Resin VS West Systems Epoxy

N

North woods Knives

Joined
Feb 25, 2014
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Hey Guys Quick Question! I'm wanting to try to seal my paracord handles and also make some micarta . Fiberglass resin is readily available in my area but I have not been able to find any west systems stuff :grumpy: . Is it really worth the price difference. Which one would work better for which applications.:confused:
 
I would take WS for both applications, but unless you are making something different than micarta you're better off just buying it. Even using the resin, if you factor in the material, pigment and everything else (clamps, a press of some sort, wax paper, mixing cups, etc) and time, it gets kind of expensive. Really depends on how much you value your time.

As for the wrap... The resin would probably be fine if you get 100% waterproof, but the viscosity can be an issue. You will likely have issues with voids and bubbles with resin. Epoxy on the other hand is usually less viscous so penetration is going to be better.

Good luck!
 
Fiberglass resin (polyester) must be sealed away from air to get a complete surface cure. It will have a tacky surface if not sealed. Sealing can be done by dissolving some wax in it or by adding a surface curing agent which you can get from Tap Plastics. Epoxy, on the other hand, will completely cure without any additives. Also, epoxy is completely waterproof, while polyester resin is not. Bottom line, use epoxy.
Tim
 
That's interesting Tim. I haven't noticed any discernable tackiness when compared to epoxy. I don't use any additives. I do sometimes apply a little wd40 just to make it purdy.

(edit- now that I think about it, my use of polyester resin always includes a sheet of wax paper on the top and bottom of the blocks of composites. Although the edges that aren't covered do get super hard, I don't know if they feel tacky per-se since I cut them off)

Also, the poly resin I'm using clearly states that it is 100% waterproof (3m's words, not mine) and I've definitely noticed a lasting durability against water and mineral oil.

I'd still go with the epoxy if you can afford to use a lot of it. :)
 
I don't know about 3M poly resin because we never used it for boat building. Back in the 70's and 80's fiberglass boats were developing blisters with great regularity. At first, they were blamed on fiberglass boring worms but subsequent research showed that water would penetrate the gelcoat and the fiberglass, causing the blisters. So, there is waterproof and then there is waterproof.

The wax paper will seal the poly resin, allowing it to reach a full cure.

If you are laying up cloth with epoxy to make a micarta type material you will need to use a serrated roller to wet out the cloth and roll out the bubbles so they rise to the surface. Pass the flame from a propane torch over the epoxy - don't impinge the flame directly on the epoxy. The bubbles will pop. This tip came from the people at Gougeon Bros., the makers of West System epoxy.
 
Old fiberglass tanks on gasoline boats like 60's and 70's Bertrams, which IIRC, used polyester that entire time, have had hell played on them by the ethanol spiked gas, which is very hygroscopic. Nylon based tanks on motorcycles like some of the Ducatis have had the same problem. The conventional wisdom is that it is not the ethanol causing the sweeping, distortion, etc.of the tanks, but the water that it attracts. The ethanol cause a whole other set of problems because it is a very good solvent and it "cleans" your fuel system and turns the deposits into gunk. Most of your good boat builders today use vinyl ester resin because while it is not quite as strpong as epoxy, it can be gelcaoted. Epoxy is UV sensitive and cold molded wood or laminate boats built with epoxy are typically painted with VERY expensive paint like Awlgrip.
tim37a said:
I don't know about 3M poly resin because we never used it for boat building. Back in the 70's and 80's fiberglass boats were developing blisters with great regularity. At first, they were blamed on fiberglass boring worms but subsequent research showed that water would penetrate the gelcoat and the fiberglass, causing the blisters. So, there is waterproof and then there is waterproof.

The wax paper will seal the poly resin, allowing it to reach a full cure.

If you are laying up cloth with epoxy to make a micarta type material you will need to use a serrated roller to wet out the cloth and roll out the bubbles so they rise to the surface. Pass the flame from a propane torch over the epoxy - don't impinge the flame directly on the epoxy. The bubbles will pop. This tip came from the people at Gougeon Bros., the makers of West System epoxy.
Click to expand...
 
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North woods Knives said:
Hey Guys Quick Question! I'm wanting to try to seal my paracord handles and also make some micarta . Fiberglass resin is readily available in my area but I have not been able to find any west systems stuff :grumpy: . Is it really worth the price difference. Which one would work better for which applications.:confused:
Click to expand...

Lumby BC


http://www.westsystem.com/ss/where-to-buy/

Being in BC, there should be lots of dealers, it's a boat thing

High Energy
8 Greenhow Rd, Vernon, BC, Canada
250-260-3102
13.31 miles away


IPS Industrial Dists
#11 - 364 Lougheed Road, Kelowna, BC, Canada
250-765-6157
29.31 miles away


Kalypso Fiberglass
715 Carrier St, Kamloops, BC, Canada
250-828-6855
66.65 miles away


Poco Marine Propellers
2532 Kingsway Ave., Port Coquitlam, BC, Canada
604-464-8773
183.45 miles away

Steveston Marine & Hardware
201-19700 Langley By-Pass, Langley, BC, Canada
604-530-7031
183.59 miles away



If you're ever looking for where to buy something, start with the website of the manufacturer and look up the distributors.

It was difficult in the days before the internet, but now it's so easy to find something.
 
That's awesome Count. Didn't even think to look on their site. West Marine in Fresno, about 50 miles away, but I need to stop by Tandy over there anyway.

Yup, ethanol sucks. Almost bought a Duc, but I can't afford a new tank. Ended up with a zuki but one day I'll have my Italian Stallion. ;)
 
Any quality boat building epoxy would be fine West is one of the big names, but System 3 makes good products too. As others have pointed out, steer clear of polyester resin. Not the least for health reasons, the hardener (MEK) is highly carcinogenic.

Any decent boat building supply or repair place should have more epoxy choices than you can choose from. :) 1234... gave you some good hints for supply.
 
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