'Thinning' Hemple epoxy filler

[pcatterall]

My hull had been slurry blasted and is now ready for a few coats of epoxy resin. Prior to the epoxy I plan to fill the numerous small imperfections ( up to 1mm deep and 2 or 3mm accross)
I did a test with the Hemple filler which I have purchased for the job. I had hoped it would go on a little like polyfilla and requiring just a quick going over with sand paper to remove the excess filler and provide a key for the epoxy.
The filler seems a little thick for just hole filling and I am having to sand down more than I wanted.
Is it possible to add a small amount of resin to the mix to make it thin enough to fill the holes without coating the whole surface? probably 10% would do the trick but I wonder if this will affect the setting.

 

[VicS]

No. It is important that the two components are always mixed accurately in the specified proportions

There appears to be a thinner that you might be able to use .. Other than "Thinner 8450" I dont know what it is.

See The prodct data sheet

 

[30boat]

I found that you can add a different brand of resin(epoxy)to epoxy filler as long as it's been correctly mixed with it's own hardener before.This probably goes against all advice but I've been doing it for many years and never had negative side effects.To be on the safe side make an experimental batch and let it harden.
For instance my engine bearers were finished off with such a mix and are fine 10 years on.

 

[TQA]

Have you tried warming the mixed epoxy up?

Mind you it will also set faster too.

 

[Delfin]

Use MEK. It is what it is designed for. You can thin any epoxy mix as much as you want with MEK, and I have used it to make penetrating epoxy of varying thicknesses depending on the application. If you read the MSDS for penetrating epoxy, you'll find it is cut with MEK, although they use the base chemical name, which I forget.

 

[VicS]

MEK is butanone

aka: methylacetone, ethyl methyl ketone, methyl ethyl ketone, 2-butanone

 

[LittleShip]

MEK is butanone

aka: methylacetone, ethyl methyl ketone, methyl ethyl ketone, 2-butanone

Smarty pants

Tom

 

[oldsaltoz]

almost all epoxy based resins ans fillers can be thinned with Methylated Sprits.

Make a test batch to check.

 

[TQA]

IMPORTANT Add the thinners AFTER you mix the resin and hardner. It does not set correctly otherwise.

Don't ask me how I know this!

 

[pcatterall]

Thanks guys, am going to get some MEK just to be safe. (5% seems recommended).

 

[Delfin]

MEK is butanone

aka: methylacetone, ethyl methyl ketone, methyl ethyl ketone, 2-butanone

Always handy to have a chemist around!

 

[Pasarell]

Thinning filler

Epoxy fillers for use underwater are now generally solvent free so they will not shrink after application. If you add a solvent to thin them they will shrink after application and either crack or leave a void somewhere in the filled area. That void or crack is likely to cause a blister in the subsequent coating at a later date. Much better to leave the filler as delivered and to put up with rubbing it down to get a fair surface.