Lacquer just scratches....

[tylereot]

Man, I hope Tonar, Cagey and some of y'all can help me with this, because I'm really stuck.

20-30 coats of Behlen lacquer, straight out of the can, applied with a brush.  Laid it on nice and thick, so I can sand until doomsday.
I finally got it all flat, buffed it up, and it's covered with swirly scratches. 

Protocol: 320 norton wet sand to get it flat.  Then norton wet 600, 1200, then micro-mesh cloths: 4000, 6000, 8000, 12000.  I'm rinsing often, wiping down with a terry towel.

These...

I saw the scratches, and went back to the 4000, etc.  Now it seems the more I work it, the worse the scratches get.  I hit it with rubbing compound and it just looks like shit.
:icon_scratch: :icon_scratch: :icon_scratch: :icon_scratch: :icon_scratch:

 

[bagman67]

I have had good luck with Meguiar's Swirl Remover no. 9 as a penultimate step in my hand-rubbed lacquer jobs (spray-can, instead of brush-on, which might make a difference).  Then I finalize with Meguiar's Show Car Glaze No. 7.  I think I'm following a recommendation from Tonar on these products.


I can bring them with me if fortune favors me with a chance to drive up this weekend; otherwise it's available at Pep Boys.

 

[tylereot]

I just can't imagine what's CAUSING the scratches in the first place.  I went over the offending pads with a 10x loupe, and could see nothing...

 

[bagman67]

Well, you've applied a lot of coats of lacquer - maybe it's just not ready to be finished.  Hang it in a closet for another couple weeks, maybe?

 

[Cagey]

Something to keep in mind is that the finer the abrasive, the smaller the particles are so it takes progressively longer to get results. It's a good argument for a power buffer, so you can get a lot more done in less time. Also, it's possible you switched up in grit a bit early at some point, leaving some scratches that are difficult to get out with a finer grit. Also, you have to dedicate a pad/cloth to each grade of rubbing/buffing compound, otherwise you have leftover abrasive from the last grit defeating the work your doing with the next highest grit.

If it is just swirl, then the products Bagman recommended are good.

 

[Tonar8352]

I always use filtered or distilled water mixed with Murphy's oil soap as a lube for the paper. It helps keep the paper from getting build up. I also soak the paper over night and that seems to help with build up too. 

These days I start with 800; the 320 had to leave some very deep scratches so you may be seeing some of them. If you are only seeing swirl marks you need to keep at it with a good swirl remove and either a micro fiber rag or a foam pad.

I suggest you take it to you local quality automotive paint supply house, show them the body and ask them to recommend the correct materials to get a glass finish. If you are not using a mechanical buffer be prepared to use lots of elbow grease and time to get the result you want.

 

[tylereot]

Great advice, thanks guys.

I started back on it again this morning, this time at the sink.  No dipping in a bucket, instead a quick rinse under running water.  Started working with the 4000, and in some places back to the 3200.  Keeping magnification handy and working with very small trouble spots at a time, it seems to be going better.  There had to be some kind of contaminant on the pads or in the bucket that I wasn't seeing.

I do have a good auto paint place close, who helped me with the paint for the Bass VI.  I might take both down to those guys and show off the VI, and get advice for the Jag.

 

[dmraco]

lot of good tips.  I suspect the 320 left some DEEP scratches.

If you have a good orbital buffer or 3 inch air buffer that are clutch!  I use two different compounds and two different sponges.  I use a finish foam and the same Meguiar's Swirl Remover.  I use a slightly deeper cut...5 to be exact.  I then have a 3M compounds that is like mayo when you put it on.  I apply with a polishing foam.

Cut can come from both the compound and the applicator.  Like Cagey said, do not mix the compound and the applicator.

Automotive paint supply should have all the materials you need. 

BTW...the compounds can get expensive.  I usually start with 800-1000 and will take it up to 4000-5000 grit depending on the progress.  I have found the compounds get out anything beyond that.

A final tip is do not apply too much pressure if using a mechanical polisher.  I usually only apply just a little added pressure.  When using my 6 inch orbital, the weight of the polisher is enough.  Pressure generates heat, and heat is not good.
Good luck!!

 

[Tonar8352]

I started back on it again this morning, this time at the sink.

I recommend against this. Years ago I asked a fine finish guy the same question you asked here and the first thing he asked was if I was using tap water, I was and he told me that was not a good idea. There are small contaminates in faucet water sometimes even small metallic  bits. I only use distilled or filtered water.

 

[tylereot]

I started back on it again this morning, this time at the sink.

I recommend against this. Years ago I asked a fine finish guy the same question you asked here and the first thing he asked was if I was using tap water, I was and he told me that was not a good idea. There are small contaminates in faucet water sometimes even small metallic  bits. I only use distilled or filtered water.

Hmm..  I can certainly use filtered water easily enough.  I've got a big filter right next to the sink for beer brewing water.
It's coming along pretty well, but it sure is taking a lot of attention to tiny details.  I'm stalking down the scratches one by one, and sanding them back using anything from 2400 on up, depending upon how deep they are and if they respond to finer abrasives.  Whew....
I hit it with some rubbing compound in a few places, which highlighted the scratches, and back to sanding.

 

[Cagey]

It's coming along pretty well, but it sure is taking a lot of attention to tiny details. 

That's the price of a good finish. It's laborious and time-consuming. That's why you rarely see OEMs putting oil or lacquer finishes on guitars any more. A catalyzed polyurethane finish only takes one coat, and it looks like wet glass when you're done with little attention after the fact. Fast and easy, plus it'll take an incredible amount of abuse compared to other finishes. Downside is, it's expensive material and you really need a special well-equipped and dedicated paint shop to do it. Plus, if you screw it up, it's difficult to recover from. You typically have to strip it and start over. I'd wager most OEMs throw the botched bodies in the incinerator rather than refinish them.