epoxy table top finish

[Chilihead]

I am making a bar top for a friend. They wanted it finished with an epoxy, basically to make it as bombproof as possible. So I have some table top epoxy from Clear Cote. I read it was a good idea to put on a thin layer first to seal the wood, and then go back with the thicker pour. Apparently this reduces bubbles. My questions is should I sand the first seal layer or just pour 2nd coat on top? Will the imperfections on the first coat or the sanding scratches show through or be hidden by the 2nd coat?
Thanks for any help.....I don't have any experience finishing anything with epoxy.

 

[Henry W]

Chilihead
Like you I don't have any experience with epoxy. That would mean that finishing test pieces is recommended.

 

[Phil S]

Many bubbles in epoxy finish over wood is caused by air within the wood. The best way to reduce or eliminate the bubbles is to make sure the temperature of the wood is dropping as you apply the epoxy and that temp drop should continue during curing. I have seen folks move a newly coated project out into the sunshine thinking that the heat will help the cure. It does speed the cure but also causes a lot of bubbles. There should be no need to sand before applying the second coat as long as you apply it before the first has completely cured.
At 70 degrees that time would be 8 to 12 hours. Warmer would be sooner. I try to do epoxy work in temps from 60 to 85. Hope this helps

 

[Chilihead]

Many bubbles in epoxy finish over wood is caused by air within the wood. The best way to reduce or eliminate the bubbles is to make sure the temperature of the wood is dropping as you apply the epoxy and that temp drop should continue during curing. I have seen folks move a newly coated project out into the sunshine thinking that the heat will help the cure. It does speed the cure but also causes a lot of bubbles. There should be no need to sand before applying the second coat as long as you apply it before the first has completely cured.
At 70 degrees that time would be 8 to 12 hours. Warmer would be sooner. I try to do epoxy work in temps from 60 to 85. Hope this helps

Hmmm......and what would you say if the first is actually already currd - b/c. i missed that 8-12 window

 

[Jeff]

Hmmm......and what would you say if the first is actually already currd - b/c. i missed that 8-12 window

Hmmm too! :icon_scra

The Clear Cote website instructions are terrible and they don't say anything about a second coat over a previously applied and cured coat! The poorly detailed instructions kind of suggest a single pour.

See this. The product is different than your Clear Cote but the idea is similar.

https://www.youtube.com/watch?v=HZHwK7tFYZA

 

[Chilihead]

Agreed, their instructions are not very good. I was trying to do a seal coat with the epoxy like the video mentioned using modpodge to reduce air bubbles. Maybe using epoxy for the initial seal was a bad idea, but its done now. Because I was trying to keep it thin and differing absorption between the sap and heartwood, the first coat is uneven. Since its cured and uneven, I guess I'll take the gamble of sanding it down a bit to level it and maybe provide better adhesion for the next coat.

 

[Phil S]

Since the first coat is already cured just sand with 220 or 320. Freshly cured epoxy tends to clog sandpaper. It will help if you clean the first coat with ammonia before you sand

 

[Matt Furjanic]

After pouring, your second pour, use a blow torch to eliminate the bubbles. Bubbles are inevitable. Just sweeping the torch flame quickly over the freshly poured epoxy will immediately eliminate bubbles. You can do this for a couple hours after pouring.

 

[Chilihead]

Thanks Matt. Did this very thing, just using a heat gun instead of the blow torch. It worked well.

 

[Chilihead]

Well for anyone following this thread, I did sand the seal coat down using 220 as Phil suggested. This was a good idea. It helped even out the surface which helped when I poured on the final coat last night. As hoped, the finish came out clear and no sanding marks show through at all. - This is not my favorite finish to work with, yet it'll be fairly bomb proof for all the beer pints I expect it'll see in my friend's house. It's a really glossy finish - wondering if anyone has ever tried dulling it down with sandpaper/steel wool? I might try that on a test piece.
Thanks for the help all!

Since the first coat is already cured just sand with 220 or 320. Freshly cured epoxy tends to clog sandpaper. It will help if you clean the first coat with ammonia before you sand