Finishing Problems

[deepsplinter]

I'm not sure if this is where this belongs, but here it is anyway.

We bought a bigger microwave/range hood, so I'm making a shorter cabinet that it will hang from. I had about an inch of stain left in the can that I used seven years ago. It was nasty and gooy, but not dried up. I only needed about a tablespoon full, so I went ahead and used it. I let the stain dry overnight and sprayed a coat of Deft (spray can) on it. I let that dry an hour or so, then brushed on a coat of Deft. I came back a couple hours later when that coat had dried only to find that it looked like hell. It was all scaley and looked milky. I hit it with some 320grit, but that did nothing. I turned the can of Deft over, it had "-11-04-DY-" stamped on it. So I'm assuming it was made in 2004.

The weird part is the inside of the cabinet was fine (it was sprayed and brushed just like the face frame, BUT NOT STAINED). That makes me think the problem might have been the old stain.

I sanded the face frame down and started all over with new stain and Deft, so it's a done deal now, but I'd still like to get some other opinions on just what went wrong.

Watcha'll think?

[Stretch]

Was it a humid day when you did the finishing? How did it look after the spray can Deft? The milky appearance makes me think of blushing which is caused my too much humidity, and can usually be prevented by thinning your lacquer 50%. We pretty much spray thinned lacquer as a standard now. It seems to fix a lot of problems we've had.

[cabinetman]

You didn't state what kind of stain (oil or water base), and I assume the Deft you used was lacquer. I don't know if Deft makes an oil base poly spray (can). I don't use spray cans.

But, with all that in mind, the stain was old, so was the spray. That specific problem sounds like the stain wasn't dry and the the spray (whatever it was) reacted . If the stain is cured, not just dry, but cured, an application of finish shouldn't react.

[TDHofstetter]

I'm inclined to think it was the humidity, too... lacquer can even be affected by your breath as you work, if you're close to the work (and probably getting stoned from the fumes ).

It MAY have been caused, though - at least the "orange peel" effect - by angling the rattlecan instead of spraying straight-on. The bloom is mostly likely a humidity effect.

Um... yeah. And if the stain was a water-based stain, and wasn't fully evaporated... there's humidity, right there - under the lacquer.

[deepsplinter]

It was oil base stain.

It all looked good after the sprayed on coat.

I don't remember how humid it was on that particular day, but it has been a little rainy here lately.

Humidity may have very well been the culprit, but why didn't the unstained part get scaley and milky?

It doesn't make sense to me.

I tossed the old stain, but I'll keep the Deft. I'll test it on a piece of scrap before it touches anything good.

[TDHofstetter]

Inside... the fumes from the drying lacquer may have been enough to drive off most of the humidity, while outside, the solvents would have dissipated rapidly. I dunno - that's only my best guess from what I know about it so far. Something else may've gotten involved, too...

[Joe Lyddon]

Are you sure that the OLD stain was good and DRY? I'm assuming that you did wipe it down good after applying it... One day to dry may have been a little short... ()

[deepsplinter]

Are you sure that the OLD stain was good and DRY?

Well, kinda sure. I didn't slather a bunch on with a brush then wipe it down. I just ragged it on then let it dry overnight.

Aaaa....who knows

[jim]

Hope you thinned the Deft that you brushed on. I always do.

[sawduster]

I'm gonna guess it was the stain. Oil based finishes go bad and don't cure as fast as they should when they're new or don't cure at all. Since you say the rest of the job with just the spray lacquer was alright and only the lacquer over the stain came out crappy, I'm inclined to blame the stain.