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I'm finishing up my latest guitar (this is number 9 or 10 for me) and I was able to give it a pretty decent polish by hand. However, I can still see some slight swirls and very light sanding scratches in the finish if I look closely in a bright light. I sanded up to 1200 grit and hand polished using 3 macguier's polishes from LMI. The finish is EM6000. I'd say the polishing job is at about 90% - do I need a buffing wheel to really get that perfect wet look? I've been thinking a buffing wheel could be that last piece of large equipment that I need....just one more....

Thanks in advance for any advice you might have.

Thanks,
Trev

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http://www.PeakeGuitars.com

By "hand polish", do you really mean by hand or are you using an orbital buffer?

No experience with EM6000, but I can get a wet, glassy look with nitro if I use an orbital buffer ($25 at Lowes). Scratch X followed by Crystal Glaze and one other swirl remover that I can't think of.

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Don't confront me with my failures--I have not forgotten them.

Well wet sanding through 1200 Cami is about 2/3rds where you need to go if you want ultra clear gloss. At this point (if hand polishing) I would get some Micromesh 3200 through 12000 that will get you to very near zero scrach depth. Then polish as you did and it will be so close to ultra clear it will amaze you.

Now if you sanded through P1200 then you need to use Micromesh 1800 through 12000

Here is a link for the cheapest place to get micromesh http://micro-surface.com

hi trev...........i put this waterbase stuff on very thin and i can get a very good finish off the spray gun i sand with 1500 grit wet and dry with water and then use a burnishing cream and it turns out like the guitar on my avatar when ever i use a machine buff i go through which means putting more finish on.....and with waterbase that means blue tint.........joe

I'm actually hand polishing. It almost works...but it just doesn't get it as far as I want!

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http://www.PeakeGuitars.com

i really hate guitars that look like candy apples with half inch thick poly and all the mess a buffer leaves in my small shop.....i would also rather not use the electricity as well...... i feel that very soon we will all have to use more and more hand tools as energy prices and feul will just sky rocket......and the world will end up like mad max films and we will have to buff our guitars with our mohicans lol

I second Michael's reply about micro-mesh, then hand buffing. That's my method and it's worked great on the 2 I've got done so far. I'll let you know how #3 turns out when I can level and buff sometime next week...

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Rob

Do you wet or dry sand with micro-mesh? I just wet sanded a new build up to 2000 grit and was thinking of trying micro-mesh. Thanks!

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John Nowicki

If it's Emtech 6000...I think I read somewhere that you should dry sand that finish. Don't remember where I saw that at though...(think it was on the Target Coatings forum). You should verify before acting on that advice.

Chris

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There is no difference between the man that thinks he can....and the man that thinks he cannot.

You can wet sand EM6000 with mineral spirits - works good. Obviously, you wouldn't want to use water.

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Steve Smith
"Music is what feelings sound like"

I tried wet sanding the first one I did, and it got very cloudy. As I worked up through the grits it got better, but it a made a huge mess. The next one I did dry, and it went much better. You have to watch for little balls of finish building up under the paper and scratching the finish pretty deeply, although I had that happen wet also. I found changing paper frequently to help. After trying both ways, I won't wet sand it again, although I'm thinking of trying the mineral spirits. I've heard a few people give positive reports of that method.

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Rob

Wet sanding reduces the scratch depth significantly for any given grit and reduces paper loading there by increasing the working life of the paper.

I have never had any issues wet sanding with water on any given waterborne finish one the finish has cured.

Michael, I stand corrected on not using water to wet sand waterborne finish. Maybe it is a matter of waiting long of enough for the finish to fully cure. But based on my experience, wet sanding using mineral spirits works great with automotive wet/dry paper and micromesh plus you don't have to be concerned with a full cure.

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Steve Smith
"Music is what feelings sound like"

I was not correcting you or did not intend to anyway. I agree that mineral spirits is great as well so is K1 kerosene. In fact I find K1 kerosene to be the best option as long as you dont plan to but a match to it

Just don't use very warm water. that will soften Waterbornes.

Michael, No problem, I didn't think you were correcting me. I had read that there were issues with wet sanding using water based on posts like Robs but have not tried it myself. I don't mind (self) correcting at all when I get information I think is from a reliable source (you).

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Steve Smith
"Music is what feelings sound like"

I wanna get a grip on this. I've done 8 guitars with Ultima & wet sanded every one (water & 25% Murphys) with good results. Now, with EM6000, I see a few warnings not to use water!! I'm thinking, has the formula changed such that all of a sudden, water is an issue??
I guess my question is...has anyone gone from Ultima to EM6000 & found wet sanding with water no longer works as well??

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Dave
Milton, ON

tap or abient temp water with Murphy's will still work fine as long as the finish is cured out. Hot water can sofen EM6000 or any other waterborne, But if the the finish is cured a bit of water and a drop of soap for lub is no problem.

Most of this post is second hand hear say, but it makes sense to me.

(I've only used waterbased finish on 2 guitars, but went away from them for various reasons. One reason was to learn about he long term durability....and it hasn't been long enough yet)


I read somewhere, maybe on the Target forum that having the finish too thick could cause curing problems. It makes sense to me that if the finish is too thick it might not fully cure under the top surface. Level sanding (wet or dry) could get down to some that isn't fully cured. If this happened when wet sanding the "not being fully cured" problem might be amplified.


Again, I haven't experienced this, I read it somewhere. Reguardless, the proper film thickness is important with any type finish. A wet mil gauge, proper finish viscosity, and alot of practice should prevent these problems.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

My experience with EM6000 was my first wet sanding any finish, so I might not have known what to expect. I did use tap water room temp, and a little Murphy's. After 10 days cure time when I started sanding, the surface got a white haze on it that I couldn't clean off and made a mess everywhere. The haze showed up anywhere water touched the guitar. I tried to clean it off, but no matter what I tried, it seemed like it was actually the top layer reacting to water. Didn't really know if this was what to expect, so I continued on through the grits up to Micro mesh 12000. As I went up in the grits, it started to get better, but even after the 12000, the was a heavy white residue all over the guitar. I then used some scratch remover and hand buffed, and that finally took care of it. On the next one, I went dry, and had a much better go of it.

Now, the question I should have asked the first time but didn't. Does this sound like a normal experience?

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Rob