Target/Oxford USL again - created 08-17-2008

Munro, Andrew - 08/17/2008.16:31:58

I know there have been a few threads on this lately, but they have expired and I don't recall anything from them. I have recently purchased some gloss USL and would like to try it. I last used KTM-9, both over shellac and epoxy, with good results on both. I am wondering how this stuff compares to the KTM in use. With the KTM I was spraying 3 or 4 just wet coats per day on 45 minute to an hour intervals. For the most part I was around 6 coats in total if I recall correctly. Is that safe to assume with USL, or can I safely spray more per day? Any recomendations on thinning, using an HVLP? I found a little splash of denatured alcohol worked well in the KTM. Also, what grit is good to sand out to before buffing with medium Menzerna compound?

Thanks.

I just remembered my other question. How long should you wait between spraying the last coat and sanding the finish level?

Andrew - 6 days. Go to the Stewmac site and look under free information. They have a complete schedule for applying Colortone (target coatings)

I was under the impression that the Colortone lacquer was the older (PSL) version, and says that it should be used after building the bulk of the finish with the corresponding sealer. Am I correct in thinking that USL can be sprayed directly over shellac or epoxy as with the KTM-9. I didn't see any mention of the sealer on Target's website, though I may have missed it.

Colortone is just a stew-mac label and corresponds to whatever the latest version of the finish that they are carying. It currently should be the USL. Although I do get a lot of stuff from Stew-mac, I do get the Target products directly from Target so I know I'm getting the latest formulation.

Am I correct in thinking that USL can be sprayed directly over shellac or epoxy as with the KTM-9

Yes.

To go back to some of your earlier questions. I've never used KTM but from what I've read as far as differences to the two is that the KTM cures harder/faster while the USL has better burn-in capabilities.

With the USL, keep each coat as thin and on the dry side although you still want it 'wet' enough for good leveling + flow characterists and don't try to build too fast. The 'wetter' the spray and the faster you build coats, the longer the cure time will need to be before it's ready to buff. You can probably do the level sanding sooner, I generally wait at least 2 weeks for the final sanding and buffing.

Target's web has a discussion forum that's a great source for info on application and spraying of their products.

I spray USL directly over shellac (made from flakes and dewaxed). I spray three coats a day to a total of nine coats. It dries hard enough to recoat in 30-60 minutes in my 42% humidity room. I wait at least a week before leveling and polishing. I had been leveling with abralon pads on an orbital sander, working up the grits to 4000. Someone, here I believe, suggested 3M P800 wet or dry paper. I tried it--it levels quickly and I can go direct to polishing. The paper does seem to lose its cutting edge rapidly. I polish by hand with LMI's "fine cut polish" followed by StewMac's "swirl remover." I've also used KTM-9. The USL is not quite as hard and polishes to a fine gloss with less work. Both look very good when polished out.

Thanks a lot; that sounds pretty similar, with the bonus of easier polishing. KTM is too hard to polish out at 800; more like 1200. Going straight to the medium on the buffer from 800 would save a lot of time. I found the same with the 3M gold; the 600 lasts a really long time but the 800 not so much. Did you spray straight from the can, or thinned?

Straight from the can.

Thanks, I'll try that later this week.

How much has this stuff really improved over the last few years? I tried Oxford PSL 4 or 5 years ago and was not happy. The finish actually wore right off the back of a guitar neck. I'm slowly making the transition from nitro over to urethane, but I swore off the water-based stuff.

I don't use the USL on my neck shafts even though Target claims to have greatly improved it. I usually use their EM8000--a conversion varnish-- on the shaft of the neck, I still use the USL on the hell and peghead where I want a nice shine. I finish the final surface of the shaft with 0000 steel wool--the matte surface makes it seem slipperier. At the suggestion of Jeff at Target, I tried their Hybridvar. Where I tried to feather it at the edge of the fingerboard and into the shiny heel and peghead, it would peel. I went back to the EM8000. I just can't stand using the solvent finishes around my house. The waterbased Target products aren't excellent but they are pretty good and the fumes aren't an issue. Other than the fact that none of the necks I've done with the EM8000 has lost its finish, I have this evidence of its durability: When I empty a jar of USL, I fill it with water and set it in the sink for a couple of days, then wash it out. When I empty a jar of EM8000, I have to throw it out. The dried residue in the jar will not yield to water, soap, or scrubbing.

Just to update; I've been spraying the last few days, and I'm really happy with it so far. It definitely wets out more than the KTM and gives much more of a gloss straight from the gun. It also doesn't seem to skin over the tip of the gun between coats, and is much easier to clean out at the end of the day. A drier environment seems to help in preventing runs and giving a better gloss. Thanks again for the advice.