Hello All,

Its been a while since my last post, all work and no fun.

I was working on a rod today and noticed that after about 8 hours of drying time, some of the expoxy had large bubbles on it?? Not sure what caused this and the finish was still pretty tacky. Now the a/c was on in the house today while the rod was drying, could the a/c have an affect on the finish??

Thanks
Fernando Torres-NERB

No. It would not cause that. Bubbles are introduced during mixing and application and you have to watch for them as they release (or try to) once on the wraps. Large bubbles may release late in the epoxy setting stage and the finish may not then flow back over the opening. The result is a large crater. If they cannot release, you simply wind up with visible bubbles in the epoxy.

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If anything the A/C would help the drying,because it pulls humidity out of the air. If your cooling is a swamp cooler it will add humidity to the air.

Humidity shouldn't have any effect on the cure of epoxy. But I tend to think that having the shop at a controlled room temperature of about 72F to 74F can't do anything but improve things for you.

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I just going on my own expereance. Here in Tx. we tend to get a little humid ( 87% here now). When the A/C is going, my rods tend to dry a little faster than when its not ( thats not very often.... LOL).

That's interesting and I don't doubt you, it's just that epoxy cures by chemical reaction, not by release of solvents or drying of any type.

I know what you mean by humidity - we've been at near 100 degrees and 90% humidity for the past week.

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Tom Kirkman Wrote:
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> >
> I know what you mean by humidity - we've been at
> near 100 degrees and 90% humidity for the past
> week.
>
> ............
Tom
I FEEL YOUR PAIN!!

The drying time might also have to do with, the house being warmer. I don't keep the A/C as low as some folks, usally around 78. After 20 years of A/C repair and hanging out in attics I like it a little warm.

I heard that epoxy forms less bubbles in a humid environment. I am not sure if this is true.

Not sure, but will be having dinner tonight with someone who is an expert in this field. I'll find out and if so, why.

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Epoxy and two part finishes will set and cure under water, so humidity has nothing to do with that, but can help cause blushing.
Mixing, application, and temp extremes(set up time) are the normal causes of bubbles.

Thanks for all the replies, I have taken off the afftected area and will apply new finish, on Friday. it was more of what Tom mentioned a crator rather than a bubble. I also noticed only in the area where it formed, it was still tacky even after two days. this was the only part of the rod that had the problem, I forgot to mention that it was over a bass decal, maybe the decal had some type of contaminant in that one area that may have caused it?? As I said before I never had this problem and always mixed my expoxy for at least 3-5 minutes.



Fernando Torres-Nerb

Can air conditions contribute the the formation of a large bubble? Yes! How? Think this through - Shop is nice a and cool with air conditioner humming away - Thread wrap with metallic trim band with both ends of metallic pulled under nylon thead - apply heavy first coat of finish - you are in a hurry to get out of the shop - watch it for a few minutes and everything fine - cut off air conditioner - go to McDonalds to get a burger - go back in shop next morning and see a huge bubble in the location that the pull was made on the metallic trim band - what happened? - temperature in shop increased - air entrained in metallic thread displaced and could not escape without blowing a crater in finish - many many times this has happened to me. Now I torch em good to expand air and blow it out before finish thickens.