Thinning epoxy

[BobSch]

I think the solvent you're asking about is MEK — Methyl Ethyl Ketone.

http://www.scorecard.org/chemical-pr...nce_id=78-93-3

I'm going to side with Loring here. Since epoxy is a checmical reaction and not just a "drying" one, thinning probably won't work.

[cabinetman]

Hey Bob

I think the last time I did fiberglass stuff "MEK" was the catalyst for the resin. Yes or no?



"I'M NEVER WRONG - BUT I'M NOT ALWAYS RIGHT"

[leehljp]

Found my links on thinning epoxy

OK, one more time on the epoxy thinning - two links:

Link that deals with thinning epoxy for different reasons -
http://www.epoxyproducts.com/penetrating4u.html

A discussion on thinning epoxy for penetrating wood pen blanks to stabilizing it. Scroll about 3/4 of the ways down and look for the answer from Mesquiteman:
http://www.penturners.org/forum/topi...=Epoxy,thinner

Another link for epoxy for sealing wood:
http://www.rotdoctor.com/epoxy/epoxymain.html

[bigsteel15]

I think the solvent you're asking about is MEK — Methyl Ethyl Ketone.

http://www.scorecard.org/chemical-pr...nce_id=78-93-3

I'm going to side with Loring here. Since epoxy is a checmical reaction and not just a "drying" one, thinning probably won't work.

That is NASTY stuff!!!

[BobSch]

Hey Bob

I think the last time I did fiberglass stuff "MEK" was the catalyst for the resin. Yes or no?



"I'M NEVER WRONG - BUT I'M NOT ALWAYS RIGHT"

It's been a long time since I did any fiberglass work, but it seemed to me that MEK was what we used to clean off our tools, not the catalyst.

[jking]

I seem to remember a short article in one of the WW mags about an epoxy based sealer. I don't remember the specifics. If I remember, I look for it tonight.

[lrogers]

Wow, this is getting more and more interesting by the minute! I asked another R/C'er (planes) here at work and he said he uses epoxy thinned with alcohol all the time to seal/fuel proof firewalls in his planes.
The little project I'm working on is for use with my helos so there could be contact with fuel. I've got some scrap so I'm going to give it a try and let you all know how it turns out.

[Esteban]

MEK is the catalyst for polyester resin aka: fiberglass.
Its fumes are very dangerous to people with heart conditions. Also found on many paint removers.

[Tom Slick]

MEK is the catalyst for polyester resin aka: fiberglass.
Its fumes are very dangerous to people with heart conditions. Also found on many paint removers.

Actually MEKP is the catalyst for polyester resin. it is very different from regular MEK, I work with both on a regular basis.
Alcohol or Acetone are considered epoxy thinners although the manufacturer of the epoxy would be your best source for info on thinning their epoxy.

[LCHIEN]

Wow, this is getting more and more interesting by the minute! I asked another R/C'er (planes) here at work and he said he uses epoxy thinned with alcohol all the time to seal/fuel proof firewalls in his planes.
The little project I'm working on is for use with my helos so there could be contact with fuel. I've got some scrap so I'm going to give it a try and let you all know how it turns out.

I guess that works if
1) the alcohol mixes well with the epoxy and
2) the alcohol evaporates much faster than the epoxy working time (so that the epoxy can maintain its integrity as the alcohol evaporates).

[lrogers]

Well, I tried it today on a piece of scrap. first observation, a little alcohol goes a LOOOOONG way. I used too much, but the results are promising. I also tried just smoothing some un-cut epoxy over the oiece and I think that worked okay too. Next step is to lightly sand both pieces and see which gives the better surface for finishing.

[Tom Slick]

here is a link to west systems page on thinning

http://www.westsystem.com/webpages/u...#thinningepoxy

[lrogers]

Okay fellows, here's my final report on this question. The epoxy I thinned (I did use to much alcohol) penetrated well, but took forever to cure. I ended up coating the piece with uncut epoxy smoothed on with a popcycle stick. It covered well and will provide the protection I need against hi-nitro model helocopter fuel. My intent was to smooth it up and paint it, but I decided it looked fine "raw".
This turned out to a rather interesting question and I appreciate all the input and links you all provided.