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Greg Caputo
05-25-2009, 11:39 AM
I'm stumped trying to figure out what I did wrong. After a few coats of finish, a plant stand made of cherry looks like it's barely been sanded, let alone finished!

Here's what I did. First coat of finish was Danish Oil. Enough to pop the grain. Wiped on. Set for about 30 mintues. Wiped off. Waited a week. The piece looked ok. Ready for next step.

Sprayed on Target USL Gloss. 4 coats, about 60 to 120 min. between coats. Also light sanding between coats. Looks good.

Final step, spray on two coats of Target USL Satin. Very light sanding between coats. Now we have the problem. Several areas of the wood are rough to the touch, discolored (from what they were,) and look as though they haven't been finished at all or even sanded very well. It's almost like the Satin dissolved away the earlier finishes.

Any idea what went wrong? Could the age of the finishes be an issue? All the finishes are more than a year old, but had been sealed tightly and didn't seem to have any problems pouring from the cans.

Just to complete the picture, all this work was done in the basement, so temperature and humidity shouldn't be an issue.

Thanks for any ideas you can pass along.

Greg

Casey Gooding
05-25-2009, 4:29 PM
Many lacquers have a shelf life of much shorter than a year. Some as little as 60 days after catalyzing.
All lacquers partially dissolve the previous coat. That's why you don't have to dust them as completely as some other finishes when you sand between coats.
My guess is some combination of the two worked together to sabotage you.
Wish I could help more. Hopefully someone else can.

Leo Graywacz
05-25-2009, 5:00 PM
Target USL is a waterborne product and it does not melt into the previous coat. Only a nitrocellulose lacquer will remelt. Newer pre cat and post cat lacquers will not melt in unless they are sprayed within an hour or so.

It does sound like you may have an age issue. Or the other problem might be when you sprayed it you didn't get it wet enough to flow out.

Conrad Fiore
05-26-2009, 9:38 AM
Greg,
The USL, and it's replacement EM6000 have a 100% burn-in technology similar to NC lacquer. This can be varified on the Target Coatings web site. http://www.targetcoatings.com/emtech-6000.html
Did you stir the USL satin thoroughly before use? I have seen in other posts where the user on an odd occasion forgot to stir the can.
I would suggest that you post your question with a photo of the defect on the Target forum site. http://www.targetcoatings.com/forum/
Jeff Weiss should be able to help you.

Jim Becker
05-26-2009, 9:17 PM
Target USL is a waterborne product and it does not melt into the previous coat.

Not true, Leo. Target USL (specifically) does have full burn-in properties similar to NC Lacquer, but it is an acrylic finish. Jeff Weiss formulated it (as well as its predecessor PSL and its successor EM6000) to have that particular desirable property, but in a water borne finish.
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Greg, if the gloss went on well, I'd be concerned about either the satin finish itself, or the application of the same. If the USL satin had been previously opened, then it may be best to sand and reapply new finish. Something is obviously amiss.

Leo Graywacz
05-26-2009, 9:18 PM
Didn't know that, learned something new today.

Mark Lambert
05-27-2009, 10:29 PM
I have had big problems putting USL directly over Danish oil. You need to seal the oil with Shellac before applying the USL.

Mark

Jim Becker
05-28-2009, 10:06 PM
Didn't know that, learned something new today.

There's been a lot of good work done in the water borne finish world in recent years...necessary, because more and more restrictions are going in place over VOC. Jeff Weiss at Target and folks at other water borne manufacturers have put a lot of effort into bringing the "desirable" properties of many VOC-laden finishes forward into safer and easy to use products. It's genuinely hard for them to get mind-share from many people who have used NC lacquer and "nasty" pre-cat finishes, but their efforts have been paying off. And folks in the hobbyist catagory really benefit because they can now spray some awesome finishes without the need for the expensive accomodations necessary with solvent based products to protect their health and safety.

Greg Caputo
05-29-2009, 9:46 AM
Some really great information from all of you. Thank you.

I ended up sanding the rough areas and applied some finish from a freshly opened can. All's well now.

Lessons learned.

Greg