epoxy and micro ballons vs bondo filler question

[trepka2001]

when fairing my foredeck with a epoxy/micro balloons mixture i ran out of epoxy. i have a gallon of bondo that i would like to use to finish the job, can i do this or will the two different compounds not bond together???

[gjrylands]

I have been told that you can put the bondo over epoxy, but the epoxy must be fully cured. You will need to sand the epoxy with 50 grit before the bondo is applied so that it will bond. Read the label on the epoxy for the fully cure time, it my be several days.

[jav]

Tricky topic. The general rule is epoxy over polyester is OK. Polyester over epoxy can be done but you really have to research each product. The safest bet is to stick with epoxy if you can.

I recently purchased some epoxy primer that is very highly regarded and and in talking to their engineer, he informed me that the use of polyester filller is fine as long as it's done PRIOR TO FULL CURE (within 5 dys). After that, adhesion to the epoxy is very difficult and not recommended.

So research befor getting too deep.

[1967 seavoyager]

Another thing to consider, Bondo is not waterproof. Dura -Glas is. But, i think i'd mix up another batch of microballoons as it would be much stronger & able to withstand the flexing of the boat better.

[gjrylands]

Another thing to consider, Bondo is not waterproof. Dura -Glas is. But, i think i'd mix up another batch of microballoons as it would be much stronger & able to withstand the flexing of the boat better.

I think that is good advice.

[randyp]

I've used both and I would stick with the epoxy and micro baloon filler. Everything said previously just backs up my experience.

[trepka2001]

thanks for all the help, i'm taking the advice and sticking with the micro ballons epoxy filler.