Epoxy - Sand and Gloss Coat Brushes

As suggested, I’ve been using cheap disposable brushes (to reduce contamination) to apply both sanding and gloss coats but the loss of bristles during application is getting really annoying. I’ve tried pulling any loose bristles out before starting but always end up with some in coats.

I’m guessing a foam brush could be used for the sand coat but don’t think they would work too well for glossing. If proper PPE is worn, can a better quality brush be cleaned with acetone for re-usage?


Herb Bean

Personally, I would never consider using cheap brushes that lose bristles on either filler or finish coat. If you must lift bristles out of the brush, wait until the resin coat/bristles are on the board and then lift them out with a blade. Of course a better brush can be reused after soaking in Acetone. I use three acetone buckets and move the dirty acetone along… 1st pail,clean resin out of brush, leave brush in second pail, and clean hands with third pail. Cover the acetone pails up to prevent evaporation. Throw out 1st pail after several usuages…

ps: Oops, my mistake…I’m talking about normal resin…

Some do reuse brushes and keep a little acetone around just for the gloss brush. Hot coats don’t really matter when it comes to a hair here or there. They won’t show or make a difference on a clear board or even on many colored ones. However when using a new brush there are ways to remove loose hairs before using. First, hit the brush hairs against the edge of a table. This will get rid of about half. Also you can comb the brush. This will also take some out. Another method is to take two inch tape and wrap it sticky side out around your fingers and then push the tip of the brush into the tape repeatedly. This gets out almost all loose hairs and leaves you to concentrate on getting a nice finish.

As for buying a better quality brush - are natural bristles preferred over synthetic?


Herb Bean

I use a mohair roller, very much like an enamel paint roller. I think the finish is a lot better than a brush and no bristles to worry about.



Alcohol will clean epoxy off almost anything better than acetone.

I go through new brushes with a brass-wire barbecue brush before starting. Seems to get 99% of the loose bristles - I might get one in a hotcoat once every 4 or 5 applications.

Edit: I don’t reuse brushes.

Foam brushes are ok at first, but as soon as the resin starts to gel - even a tiny bit - they drag & skip and you get self-leveling problems after your stroke. Stick with bristle.

A triple ethanol bath is a great way to keep a high quality brush ready for your hot and finish coats with epoxy. Keep the three containers well sealed of course. I’ve found no need to use acetone when I’m working with epoxy. A high quality natural bristle brush will do many boards and as long as you keep your containers at the ready. You’ll end up with a brush that’s ready to go a few minutes after you done with final wash with dish soap and a wrap in newspaper with a rubberband, It’s the way I maintained my good varnish brushes. It works for epoxy too. A few selected 1" ~ 3" dedicated brushes will last years and just make good sense to me.

Ethanol is sure much nicer to deal with than acetone and fighting all those wild bristle is just a needless frustration IMHO.

Mahalo, Rich

We’ve always used natural hair brushes. They seem to work better.