Looks like the armrseal wasn't fully cured

[smorris]

This morning I had a cup of coffee and set it on the new tabletop while I went to do something. Came back and when I lifted the cup noticed a ring of blistering in the finish, not bad but noticeable from the right angle. What the....nothing to do for it right then so carried on.

We had dinner and put down a pad and heat pads (aka potholders) under anything that was hot while the family gathered to feast and share in the day. When we picked everything up, anywhere that something warm had been put had distinct blistering in the finish. This had cured for about 3 weeks so apparently the cure time for this finish is easily a month and reading up on the web I see that this isn't an unknown problem with some people recommending a 60-90 day time to full cure before you put anything hot (100 degrees or hotter) on the finished surface.

Guess I know what my project will be after the first of the year, redoing the tabletop. LOML was so upset, she thought she had done something to spoil the finish. Nope, just the way it is I explained, no big deal I'll just sand it down and refinish. Sometimes it just ends up that it takes longer than we thought to cure all the way.

In the mean time, I'm going to put some armrseal on a piece of scrap and start testing over time to find the actual cure time when it is dinner safe.

[smorris]

Follow-up. I found an armrseal finish sample I had done back 4 months ago so I put a cup of hot coffee on it. It left noticeable marks on the finish, though not as bad as the blistering. Maybe this isn't a good finish choice for the tabletop. Time to rethink this...maybe lacquer would be better for this application.

[cabinetman]

Follow-up. I found an armrseal finish sample I had done back 4 months ago so I put a cup of hot coffee on it. It left noticeable marks on the finish, though not as bad as the blistering. Maybe this isn't a good finish choice for the tabletop. Time to rethink this...maybe lacquer would be better for this application.

Sorry you had such bad luck. Could have been a bad batch, or applied too thick. Some of the packaged finishes can use a thinning. Naptha works faster than mineral spirits, for oil base varnishes and urethanes. Lacquer would be better, or my choice would be a waterbase polyurethane.

Don't feel so bad. I got a call once from an irate client to get them out of a jamb with a residential bar top. When I got there and saw what happened, it was really very funny, but I couldn't laugh in front of the client. Seems like setting up the bar to celebrate the remodel of the room, they set up glasses at one end ready for use. By the time the party started the glasses were stuck to the top.

What happened was that the company doing an epoxy pour, either had a contaminated batch, or their mix was off. Funny thing though, they thought the top was dry.
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