Removing a bad batch of epoxy

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jbo_c
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Removing a bad batch of epoxy

Post by jbo_c »

So, I can finally stop being proud of myself for not having mis-mixed a batch of epoxy. I finally screwed one up Friday evening.

One disadvantage of working wet on wet: if you screw up the first batch, you have to remove all subsequent work to get to it and fix it. BAH !!!! Happily, it was a (relatively) small overall area and I’ve pulled off the three(!!!) layers of fiberglass above the bad batch.

The question is, how do you remove the gummy bad batch now that it’s exposed? It was a “neat” coat prior to glassing, so there’s no more glass to get off. You can’t really sand it - gums up the paper instantly. I thought maybe vinegar would do it since you can clean uncured epoxy with it, but that doesn’t seem to be working.

I did do a root cause analysis and I think I have a method to make sure it doesn’t happen again.

Thanks.

Jbo


PS: After the realization and subsequent correction, I may be looking for a new church. I you know one in the Gainesville, Georgia area that might still accept me, reach out. LOL

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Re: Removing a bad batch of epoxy

Post by OneWayTraffic »

I'd start with acetone, after you've scraped everything you can.

TomW1
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Re: Removing a bad batch of epoxy

Post by TomW1 »

+1
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bklake
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Re: Removing a bad batch of epoxy

Post by bklake »

I have not used this tool for this situation but have for other epoxy related situations. A carbide blade paint scraper. I can't explain why but it does such a great job removing stuff. Far better than a similarly sharp steel scraper.

jbo_c
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Re: Removing a bad batch of epoxy

Post by jbo_c »

I use one for removing threads and roughness in finished glass layups prior to sanding. I wondered how that would work.

Jbo

jbo_c
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Re: Removing a bad batch of epoxy

Post by jbo_c »

Tried the acetone when I got home this evening. Definitely not quick if it’s going to be the best. Did a fair amount of scrubbing with acetone and a green pad. Still tacky. Will work on it some more.

Jbo

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Re: Removing a bad batch of epoxy

Post by TomW1 »

jbo_c wrote: Mon Nov 07, 2022 2:13 pm I use one for removing threads and roughness in finished glass layups prior to sanding. I wondered how that would work.

Jbo

Sanding that not cured epoxy will gum up a sandining pad in about a minute. 8O Tom
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jbo_c
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Re: Removing a bad batch of epoxy

Post by jbo_c »

Undeniable, Tom. I was referring to the scraper. :)

Have also wondered about using a wire wheel but don’t want to be flinging uncured epoxy all over myself. Can’t be healthy.

Jbo

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Re: Removing a bad batch of epoxy

Post by OrangeQuest »

Try going back to the vinegar and scrubbing pads. Maybe even try a little dawn dishwashing soap mixed in with the vinegar. If it is gummy, you want it to stop sticking to itself.
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Re: Removing a bad batch of epoxy

Post by Jaysen »

I'd use the scraper to get "most" of it off. Use the vinegar/acetone/soap, but with the scraper, you can just wipe the tool clean. You may want to take just a bit of the wood off with the scraper as well to get any bad gel out of the wood pores.

I found that "a scraper like device" (in my case random piece of sheet metal) made cleaning raw resin off a plywood floor much easier.

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