What kind of finish/spill caused this?

[Wild Turkey]

LOML bought a shelf unit with solid wood (probably oak) top for her work-center in "her" garage at the new house.  (Her garage as opposed to MY shop
 )

It had some kind of clear finish on it, possibly with a light stain, so I sanded it with 120 grit on my ROS, cleaned carefully and applied two coats of poly floor finish.

90% of it did well, but the other 10 bubbled, fish-eyed and didn't cure, just stayed sticky and balled up under sandpaper.

Cleaned, gave it another day to dry and tried again, but same result so today I stripped it (twice, scraping between and finishing with a MS wipedown per instructions) and will hit it with the sander again tomorrow before trying again.

Would a catalyzed lacquer cause problems with poly?  Did it have some silicone on it to cause bubbles?  What would keep the poly from cluring in one 1 foot circle?

Any ideas/ guesses??

[jteneyck]

It must have had silicone or something similar on it.  Stripping it and wiping several times with MS or Naptha should resolve the problem.  The best way to assure success is to give it a coat of Sealcoat shellac after it's prepped for finish, before applying your topcoats.  Use rattle can shellac if you don't have Sealcoat; it's dewaxed, too, and perfect for small projects.

John

[Snipe Hunter]

It must have had silicone or something similar on it. 

 

Probably spilled car wax. It doesn't take much.

[Wild Turkey]

Stripped, scraped, sanded and refinished and all is well.

Thanks for the help!