# Monkey Pod: Tung Oil Bubbles



## JDE134 (Aug 19, 2019)

Attempting to finish a monkeypod slab table, and applied my 5/6th coat of Tung Oil. 
The table is glass aside from a few spots where the tung oil has bubbled near the mouth of some of the cracks in the table top. Moisture indicator put it at high side of "low" "10-11%"
Sanding with 2000 grit seemed to be gumming up the "bubbles" with electric hand sander, and hand sanding leaves what you see in the third photo.

Don't want to have to bring it all the way down to 220/400 grit and work back up and really don't want to wait 6 months to let it dry out more…
Any ideas/options? 
Help?


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## bondogaposis (Dec 18, 2011)

I see a couple of problems, one is that you are trying to get a film finish with an oil. Two, you must fill those cracks. I would try wet sanding with 400 grit using tung oil, hopefully the slurry will fill the cracks, wipe it tight and let it cure. Top coat with oil based poly.


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## Finn (May 26, 2010)

I have also found tung oil to be a problem.


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## pottz (Sep 15, 2015)

> I see a couple of problems, one is that you are trying to get a film finish with an oil. Two, you must fill those cracks. I would try wet sanding with 400 grit using tung oil, hopefully the slurry will fill the cracks, wipe it tight and let it cure. Top coat with oil based poly.
> 
> - bondogaposis


+1 i only use tung oil as a blend with something else.


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## JDE134 (Aug 19, 2019)

I used a "Tung Oil Finish" which most likely has the very minimal amount of actual Tung Oil in it. I assume it is most likely a blend, but not a poly. 
Wet sand with the same Tung Oil Finish I have been using or switch to a different oil/blend?


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## Lazyman (Aug 8, 2014)

Along with the other problems mentioned, above, I think that the cracks are a big part of the problem. I don't know if calling it surface tension is the right term but I think that the finish is sort of pooling around the cracks and making it a little thicker there which slows down the curing process. Try wiping it down with some mineral spirits and see if that helps. You will probably just have to wait a while for it to cure before you sand it and see if a thinned coat will smooth fix it.


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## CaptainKlutz (Apr 23, 2014)

+1 If you use more than 3-4 coats of Tung oil trying to build a finish, then use a proper film finish - polyurethane or lacquer.

IMHO - If was going to spend the time/energy to use epoxy/turquoise to fill the large defects, and piece had very numerous cracks shown; would have filled ALL the cracks with epoxy to ensure the cookie was stabilized to prevent crack propagation. 
It would be only way to get a nice smooth finish. Plus tung oil finish will not cure properly if it can't soak into surface, such as on top of epoxy. If it does cure, it will be soft for a very long time, and have poor adhesion.

Suggest best action is: 
sand it down to wood, fill the cracks with tung oil/sawdust or epoxy, sand free of defects, top coat with poly.

Best Luck.


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