# Help needed: handling issue in epoxy resin finish on table top



## contento (Feb 13, 2014)

I've built an ash table top and finished it with epoxy resin following the directions provided to me previously for another project by Charles Neil (prep, seal coat, flood, wet sand, rubbed, etc). I have the top buffed down to a beautiful buttery satin, but I've got a couple of strange issues that came up….literally.



















First, I've got some pits in the epoxy. Normally, i would have that it was bubbles that came up during curing that didn't get taken care of, but I was diligent with the torch. It's possible I missed them and now I have to deal with them. Charles suggested previously to abrade the pits slightly then drip a bit of resin in to fill with a toothpick. That'll be the plan unless depending on the answers/suggestions I get to the next part.

the bigger issue is that I've got a couple of areas (a couple small and one pretty large) that appear to be raised "bubbles" of resin. They are higher than the surface and appear wavy (not glassy smooth like the rest). Something obviously happened to these areas during the pour or curing, and I have to figure how to handle them.

What I'm considering:
- trying to sand them down as flat and close to the surface as possible and hope I can sand and buff them to look like the rest of the table. If I can't get those areas to look and feel like the rest, can I do another flood pour over the entire top to resolve it?

- remove the epoxy in those areas down to bare or nearly bare wood. Obviously, this might be a very tricky prospect (trying to sand a hole in the epoxy). Then, fill those areas back up to surface level and return to finishing. Will I be able to hide the hole with the new epoxy or might it look dramatically different from the rest of the top?

I would love to hear suggestions as to what might have caused it and what you think is the right way to attack it.

thanks all.


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## contento (Feb 13, 2014)




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## wormil (Nov 19, 2011)

I would do what Charles Neil suggested and then scrape down the high spots and rebuff the whole thing.


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## contento (Feb 13, 2014)

> I would do what Charles Neil suggested and then scrape down the high spots and rebuff the whole thing.


Thanks, Rick. I did do what Charles said originally to get the top finished. I'm hoping to hear from him and other experts like you here on how to tackle the problems.

When you say "Scrape" what do you mean? scrape with a blade or sand?

There may be another "sticking" point - excuse the pun. I tried sanding down one of the small high spots (smaller than a dime), and when I did, it was sticky underneath. Granted, this was only a couple of days after the pour, so if that high spot was indeed some kind of bubble, I could see how it wasn't cured thoroughly. I've let it sit now for a few more days and that sticky spot has hardened up. I'm hoping that if I do cut into those other spots, they don't become a gooey mess.


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## CharlesNeil (Oct 21, 2007)

this is either a contamination issue, but more likely a mixing issue. Meaning for whatever reason the hardner didnt get fully mixed .
With that in mind the question is will it ever really cure ( just the spots ). 
If it were me I would take a chisel and using it like a scraper , scrape out the soft material, then using some acetone, scrub down in the divot, . My reasoning here is so you dont have to did it all out and risk scratching the wood, , the acetone should remove any remaining uncured material. 
Once clean, repour the divot , just slightly over full ,. When cured block sand it back to level and re buff .
My experience has shown that the repair will be invisible.


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## Tennessee (Jul 8, 2011)

> There may be another "sticking" point - excuse the pun. I tried sanding down one of the small high spots (smaller than a dime), and when I did, it was sticky underneath. Granted, this was only a couple of days after the pour, so if that high spot was indeed some kind of bubble, I could see how it wasn t cured thoroughly. I ve let it sit now for a few more days and that sticky spot has hardened up. I m hoping that if I do cut into those other spots, they don t become a gooey mess.
> 
> - contento


Since epoxy cures chemically, not with the help of open air, my bet is you have a spot that didn't get mixed well enough, and it will stay sticky for a long, long time. If the one spot finally cured, it had enough hardener in it to finally set. Only time will tell on the other areas.


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## contento (Feb 13, 2014)

Thanks all. Sounds like I have a plan of attack. Appreciate the time to chime in.


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## BobAnderton (Oct 5, 2010)

The OP didn't say there were areas that didn't cure or were soft, or sticky.


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## contento (Feb 13, 2014)

> The OP didn t say there were areas that didn t cure or were soft, or sticky.


Yes he (I) did, just not in my first post.



> There may be another "sticking" point - excuse the pun. I tried sanding down one of the small high spots (smaller than a dime), and when I did, it was sticky underneath. Granted, this was only a couple of days after the pour, so if that high spot was indeed some kind of bubble, I could see how it wasn t cured thoroughly. I ve let it sit now for a few more days and that sticky spot has hardened up. I m hoping that if I do cut into those other spots, they don t become a gooey mess.


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## contento (Feb 13, 2014)

Well, unfortunately, I was not very successful in removing the 1 of the uncured areas. I've come to the conclusion that the top needs to be sanded and re-poured. I'm going to tackle that (sanding) tonight.

I need to mix a large batch of the resin for this table (40" x 84"). Obviously, I have to insure thorough mixing to avoid this issue again. Are there any tricks of the trade I can implement? I've read that a wider container (not taller) will slow the curing time down. I mixed previously only by hand, but should I use a mixing bit in my drill (low speed to avoid introducing too much air)? Finally, can I thin this mixture a bit with acetone to make it flow easier like with the seal coat? What % is safe that won't effect the finish hardness but effective enough to aid in the resin flowing and leveling?

thanks again all!


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## CharlesNeil (Oct 21, 2007)

Im curious as to what became the issue .. ?


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## contento (Feb 13, 2014)

craftsman inadequacies. LOL

I went about lightly scraping the soft spots and did fairly well on a couple of the major ones. Was able to get through the soft top layers and sanded/feathered the edge smooth. Those areas would take the re-pour ok. One area was very problematic. As I removed material near the edge of what I thought was the edge of the affected area, the area adjacent would begin to peel a bit. So, I had to extend my scraping a bit further. This went on and on. Ever pick at a small paint chip only to peel the paint off an entire surface? My half-dollar sized area quickly became double that with no clear end in sight. I couldn't get a good edge on the area that I could sand and feather out. I tried creating a hard edge by using a razor blade and that worked a bit, but not great.

Charles, do you have any recommendations on preparing and pouring a large volume of epoxy? I picked up a wider plastic tub instead of a taller, narrower one. I also have acetone, mineral spirits, denatured alcohol. Can I/should I think the mix a bit to help it flow and if so, with what and to what percentage?


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## CharlesNeil (Oct 21, 2007)

What epoxy are you using ?


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## contento (Feb 13, 2014)

https://www.amazon.com/gp/product/B01LYK2NAG/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

I've had great success with it on previous projects


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## CharlesNeil (Oct 21, 2007)

ok , so as i understand it , this is raw wood, you did the seal coat, no dyes no stains, just well prepped raw wood , am i correct ?


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## contento (Feb 13, 2014)

yes sir.

I'm thinking the issue comes down to trying to mix, spread, and pour such a large volume of resin the first time. I know not to scrape the barrel to get more out, but I did everything else I could to get every drop on the table. That's why I want to mix a very big batch this time. I'd rather throw an unused mixed pint away than come up short.


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## CharlesNeil (Oct 21, 2007)

Im not so sure .. 
formulations are changing constantly , and sometimes things change, just saying .
Not to say this isnt a good product , but obviously something went wrong with curing and adhesion, Im going to ask Monte Pittman to chime in here, he does alot of epoxy and lets see what he has to say ,

Good informative thread, we all learning, unfortunately at your expense,.


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## CharlesNeil (Oct 21, 2007)

folks, I will pick this back up in the morning, got a nice case of the flu going on, , will get with Monte and see what suggestions he has , I use a different epoxy, we will talk more later . Will be interesting to see what he uses, 
mixing is important, but having to stand on your left foot , while scratching your rt ear, shouldnt be the case, .


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## contento (Feb 13, 2014)

appreciate it Charles! Feel better.


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## mojapitt (Dec 31, 2011)

Mixing large batches has come back to haunt me. Epoxy is wonderful and yet can be the most evil finish to use. Because proper mixing is essential, large batches makes it easier to have an improperly mixed spot in there. Also if you don't scrape sides and bottom of the container off during stirring, as well as the stir stick, they carry unmixed product on them that can transfer to the pour and cause soft spots. I also never scrape the container clean when pouring because there can be unmixed product that gets transferred to the project. Temperature should be 70°-80°. Too cold has affected the pour a couple times for me.

All of that may sound pretty picky, but having to do it over is worse. BTDT!


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## contento (Feb 13, 2014)

thanks Monte for chiming in. I'm pretty careful with the mixing and scraping (or not), but this is the first time I've tried to pour a volume like this. I'm certain it was a failure to mix well enough that caused it.

Have you used a mechanical mixer of any kind without introducing to much air? Obviously, not whipping into a froth is key. lol

Any opinions on thinning it to make it flow out better for a final, flood pour?

On a side note, I thought I'd do a pour inside my house once (no workshop dust, bugs, etc). MISTAKE. We keep the air around 69-70 degrees in the house. It caused the epoxy to BEAD UP AND POOL in the weirdest way.


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## mojapitt (Dec 31, 2011)

Strictly stir stick. But being too aggressive gives air bubble problems and being too cold makes it hard to get air bubbles out.


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## woodworm1962 (Feb 15, 2018)

as far as I know you can sand it down and actually pour more resin over the top again. You need to run a torch or a heat stripper gun over the resin after you pour it to get the air bubbles out and it will also run/float/spread/flatten faster when yo hit it with the heat.

ALSO here is a tip for everyone on here about mixing this resin.

I worked at place that mixed and poured huge amounts of resin every day, so I trust what I learned.

They would first off be very clean and very accurate with measurements. then pour the resin and hardener into the first cup/bucket// mix mix mix well THEN VERY IMPORTANT Pour the contents into a brand new clean second container making sure to scrap the first one very good out in tthe new one MIX again.


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## mojapitt (Dec 31, 2011)

Very solid suggestion woodworm. I use a torch for getting bubbles out. That being said, move quickly with torch. You can light it on fire. Done that also.


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## CharlesNeil (Oct 21, 2007)

Looks like we got some good info here .. hope it all works out


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## contento (Feb 13, 2014)

I do use a torch on the bubbles and try to be diligent with it (Every 5-10 minutes for an hour or so while they come up). I like the idea of moving from container to container. I read that elsewhere tonight as well, so that'll be the plan when I get to that this weekend.

thanks again all! Really appreciate the time and effort.


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## jimintx (Jan 23, 2014)

This has been a really fascinating thread for me to read.

Long ago, I used a lot of resin in boat building, and some boat-related repairs. It was always brushed on, not poured on. (WEST system epoxy was an evolving innovation in light-weight boat building back then.)

Fortunately, I never had to deal with these type of peculiarities. For example, I never heard of torching a resin application while it was drying. I really would like to see that! In fact, I will now put that on my endless list of things to study via youtube.

Best of luck with it. It seems like a big job and a large expense to repair your surface.


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## contento (Feb 13, 2014)

the torch/heat effectively pops the bubbles the form. I've seen a couple of videos of guys doing REALLY big pours using giant flame throwers. Pretty wild.

The cost to repair isn't too bad. It's the effort and the time that stinks!


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## CharlesNeil (Oct 21, 2007)

Absolutely ,flashing a butane torch over it gets the bubbles out .

Here one for ya to ponder….
Sitting buckets of dry ice so the vapors go over it will also remove them as well as exhaling on them .
I have see large pours made , with the ice and a small fan to drift it over , same as you see in a music video , or similar .


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## contento (Feb 13, 2014)

> Sitting buckets of dry ice so the vapors go over it will also remove them as well as exhaling on them .
> I have see large pours made , with the ice and a small fan to drift it over


Might have to try that! Would be much easier than manually torching it every few minutes and I think NOT adding the heat may prevent some variances in curing .


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## CharlesNeil (Oct 21, 2007)

I seen one done with a tent of sorts and just let the vapors build up.. but be careful .


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## contento (Feb 13, 2014)

wont be testing on this one, but will definitely give it a try on a test piece.


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## CharlesNeil (Oct 21, 2007)

This is an example of how a thread should be conducted .. Well done to all 2225 views … Nice


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## contento (Feb 13, 2014)

UPDATE:

I couldn't bring myself to pour the entire top again without making a more thorough attempt at repair, if for no other reason, to know for future reference.

I sanded the two major failures down to bare wood and feathered the edges smooth to the finish epoxy level creating a smooth sloped divot. One was about 5" in diameter and the other about 3". In addition, I used a tapered dremel sanding/grinding tool in each of the pits left by bubbles to create a uniform hole for each.

I followed the products exact mixing ratio and followed the two-container method as well as using a new stir stick in the second container. I didn't scrape the sides of the first container when pouring into the second. I made sure I mixed plenty to not have to worry about it. I poured enough into each major divot to fill it slightly above the finished level. I used a toothpick to drip just enough to do the same into each of the small holes. I followed behind with my torch to keep it all bubble free. I let it cure for nearly two days to make sure it was fully hardened before I started sanding.

I went at it with 220grit on my random orbital and used soapy water for lube and kept it clean. I attacked all of the repair spots and got them cut down smooth. I followed behind with 400grit wet then 1200grit wet.

All told, the repairs are nearly invisible. The large divots have a slightly different color but it almost looks like just part of the tone of the wood. The holes vanished completely. Unfortunately, I missed a few!! Where is the angry face emoji? As I was working the surface, I found a few tiny holes that I failed to refill, so they are currently curing.

Once I take those down the same way, I'll hit the entire thing with 1200 wet once more, then the 1000 and 2000 abralon pads and then buff it all out with the swirl remover.

more to come…


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## CharlesNeil (Oct 21, 2007)

Excellent


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## jimintx (Jan 23, 2014)

It is quite excellent, and it undoubtedly is going to look fabulous.

And, it sure does not make me want to mess around with doing an epoxy table top. 
Whew, a touchy finishing method!

I hope to see the pictures.


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## contento (Feb 13, 2014)

> And, it sure does not make me want to mess around with doing an epoxy table top.
> Whew, a touchy finishing method!


Don't be skerd! It really isn't that bad. I'm a perfectionist. I've had great success with a variety of pieces and finishes. Start small and work your way up. I wouldn't have wanted to try this giant piece as my first!












































(this was my first thanks to Charles!)


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## contento (Feb 13, 2014)

ok, folks…she is done! I went through a couple more repairs, and I'm very happy with the results. Thanks again to all who chimed in!


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## Stumble (Mar 11, 2018)

I joined just for this thread. I have a lot of experience working with epoxy in boat building, and have a couple of suggestions.

1) As you discovered poor mixing of large batches is a real problem. So it is critical to mix it well, then mix it some more, then finally mix it just to be sure.

2) If you do have a bad batch sanding can be difficult because the gummy epoxy can clog sandpaper, then the heat instantly sets the gumming residue on the paper. So I would suggest grabbing a hand jointer or a hand planer if you have one available. Particularly when removing epoxy from large flat surfaces they make it relatively painless.

3) If you are going to do a lot of epoxy work invest or make a vacuum chamber. Basically just a strong pot with a vacuum pump. The goal is to de-gass the epoxy and pull the suspended air out of the epoxy before it hits the parts. It looks like you a boiling it, but the off gas is really just suspended air trapped in the resin. doing this also acts to mix the epoxy one last time so there is that…. You can buy a vacuum chamber for about $80 plus a pump (any HVAC vacuum pump will work), or build one pretty cheaply, they are just a large pot and a lexan lid with a seal added.

Video of epoxy in a vacuum chamber - 



How to make a vacuum chamber - 




4) Never ever thin epoxy. This is not paint or a finish that cures based on exposure to air, it is liquid plastic and introducing additional chemicals will change the way it cures. Introducing thinners can actually make the final product turn gummy, put pin holes in it from the VOC's escaping, and ruin its appearance. If you need a thinner epoxy buy a thinner epoxy, but do not thin what you have.


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