Using filler in epoxy

[saurav16]

Just wanted to verify that using a filler just thickens the epoxy? Hardener just changes the working time? If you are filling voids from a wet deck would you use a filler?

[Freesail99]

Yes a filler thickens the epoxy. The hardener is the "part 2" of epoxy. There is no epoxy without hardener. Yes it will affect working time, but I would follow the directions. As far as filling in voids in a wet deck, two things come to mind. Is the epoxy just a bandaid ? Will this fix the problem ? Second, how deep are the voids ?

[johnhalf]

You are correct, although there are some differences in working time between thickened and unthickened. Check out http://www.westsystem.com/ and go to product information, and then user manual, lots of good info on their web site.

[Jeff_H]

The speed of the reaction should be controlled by the type of hardener used (slow or normal) rather than by the amount of hardener. I am a big fan of MAS epoxies for what you are doing since they do not form an amine blush. Often you are recoating or refilling an area and you don't have a way to clean off the amine blush formed on other brands of epoxy. MAS supposedly has less allergens as well.

Jeff

[sailingdog]

IIRC, one other thing nice about the MAS epoxies, is that you can mix the slow and fast hardeners to alter the curing time a bit, which you can't do with the West System normally.

[arbarnhart]

Originally Posted by sailingdog

IIRC, one other thing nice about the MAS epoxies, is that you can mix the slow and fast hardeners to alter the curing time a bit, which you can't do with the West System normally.

Really? I have used epoxies from half a dozen different vendors over the years (RAKA was my favorite) and I never encountered that. Sometimes figuring the proportions could make your head hurt, so I would just mix some slow and some fast and then mix the mixes. A few of RAKA's "kits":
http://www.raka.com/EpoxyPricing.html
include a mix of your choice of hardeners. I used RAKA when I built this from scratch:

a few years ago. And yes, that was a lousy lug sail in the picture. I l;ater made a sprit for it.

[camaraderie]

Thanks for the clarification Andy...for a minute there I thought you'd stolen one of CD's solar panels!! (g)

[arbarnhart]

It actually sailed okay in light winds,but it had a bad lee helm and would have disappeared over the horizon if I had fallen in. I had a real learning experience about taking shortcuts on that boat. I mixed some fast and slow so I could do 2 strakes in one night. I pushed the time window a little too tight and had Murphy's law kick in and a couple of spring clamps pop off and out of reach while I was alone in the garage. I had to stand and hold the strakes in place at one end for about an hour and a half.

[saurav16]

The void is from wet deck. Ground out the wet core and want to fill with epoxy and will paint later. This is all under stanchions.

[arbarnhart]

Hopefully you know this, but just in case...

Use slow hardener when filling voids. Fast hardener causes the epoxy to get very hot; hot enough to melt plastic mixing cups (DAMHIKT).