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So I've been trying to get a smooth lacquer finish on the guitar. I'm using Mohawk M610-1406. I keep getting pore spots, dimples, bubble pockets, it looks like someone took a toothpick and dotted it. it's hard to explain. It's all shiney and nice after spraying but dries weird. I've sprayed thick, wet sanded, added thinner and Cardinal SB-09 retarder. No matter what I do it pops up when it dries. More retatder? Will it buff out?

I'm trying to upload pics, but it won't let me.

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Jason Moe
LaCrosse WI 54601

Sounds to me like some kind of contamination. Without seeing it I would suspect fish eyes. That is where the surface gets contaminated with something like car wax or furniture polish (Pledge) and the finish ends up with pin-holes that the finish will not cover. The only way to get rid if it is something called Fish Eye Remover which (funny) is actually silicone. Or you can remove all existing finish and use wax and grease remover (found in automitive stores) to clean the surface.

Although your issue may not be that and without seeing it it would be hard to diagnose.

Bob

As said above, difficult to diagnose but what Bob said seems sensible. I’ve seen this happen.

I haven’t seen it, so this is only conjecture. Sometimes spraying too close to the surface or with too much pressure will cause bubbles. Sometimes water in the air line will cause defects.

If it is indeed silicone (even hand lotions can have it in the ingredients—touch your surface, you’re screwed), you’ll probably want to sand back as far as needed to get a good surface, clean throughly with clean rags and solvent, put on a coat or two of shellac to seal it, and work up from there.

Using fish-eye eliminator is a life long commitment. Once you get it in your spray equipment, you can’t get it out and you’ll always have to use it. I recommend keeping it far away from your shop.

I figured out the photos. I had to resize them.

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Jason Moe
LaCrosse WI 54601

We need more info What sort of spray set up? HVLP? Which exact brand and name of finish? What is your environment your spraying in? Do you have a water separator? Multiple stage moisture separator?

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from your wording it might be solvent pops...retarder helps with this but from my experience it can be caused by spraying another coat too soon...retarder can actually make this worse as it will stay in the previous coat slowing down it's cure. making the effects of this go away is a royal PITA as it requires sanding down until you have no dimples left. I'd say let it dry for a good while (probably a week at least, more if you've gone a bit overboard with retarder), sand it back and spray thinner coats and let them dry more then you have been before spraying another.

This has helped me many times. Save a copy in case it disappears

https://howardguitars.blogspot.com/2015 ... 8.html?m=1


Sent from my iPhone using Tapatalk Pro

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That is not nessesarily true, I sprayed cars for over 25 years and FEE (Fish Eye Eliminator) is an unfortunate nessesity when spraying lacquer. The trick to using it is to not to put more than a drop or two in your mix. More and it will do as you say but when used correctly it works just fine and yes, you can clean it out of your spray equipment. What you do not want to do is keep the bottle of FEE in your shop without being in at least a zip lock bag or another contaainer. I keep mine in a tupperware container in my garage away from my shop or anthing it could contaminate. I only use it when absouletely nessesary and then in very small quanities (just enough to get the job done). It is true that once you use it on a part, that part will usually need to have a drop of FEE to stop more fish eyes if you re-spray it.

Having looked at your picture it isn't clear that this is fish eyes, I see a couple of spots that may be but the finish is really orange peeled. Too thick of clear, or too low of pressure will cause that look.

Solvent pop is usually something that happens weeks after a finish has been sprayed. That is where the top surface dries and leaves solvent trapped under the dried finish. Solvent pop looks very different than fisheyes looking up close. Fisheyes will get a mound of finsh all around the little dot that won't accept finish. Solvent pop looks more like little round chips.

It is difficult to tell from your picture what the issue is but I would give it a couple of weeks dry time, level the finish out and let it dry another few days (once you break the surface it will alow the finish under it to dry further (your finish looks pretty thick).
Then when you know it is fully dry, spray another coat of clear on but thin it down about 50% with straight thinner (NO RETARDER). You will know right away if it is contamination because the new coat of thinned clear will do the same thing.
If it does, you will need to strip the finish and start over or put a drop of FEE in your clear.

But if you do get FEE, keep it out of your shop and in a tightly sealed container. ONLY USE IF NESSESARY. Bob is correct that it can cause huge problems if you contaminate your shop. I rented a shop with another painter/body man and he pumped about 6 squirts of FEE in a job he was doing because of fisheyes. He completly contaminated the spray booth and we had to pull everything out, clean it and re-paint the spray booth to get rid of it. So it can be cleaned out but it isn't a fun thing to do.

I wish you luck that it isn't fish eyes and a good leveling will do the trick.

Bob

Severely orange peeled. Usually the lacquer dried too quickly for it to flow out. Try adding reducer.

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