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Man have I wore myself out on this one. I have two finished under EmTech 6000. One is EIR, and in corners (neck joints) you can catch a bit of the blue haze under intense light. But normal house light? Nothing. I have the other (Harp Guitar) finished as well, lighter wood, bubinga. Can't find the blue haze. I took more precautions to keep the finish thinner too.

What is amazing to me is that on the EIR "Martin" OM, the neck feel is astounding. I have played this guitar day in and out for over 3 months and it still feels as good as day one. No stick. Smooth as silk. And pretty too.

Benefits are, low cost (~$40/gallon) and that will do about three to four bodies. YMMV. Works well with CA. I know some might feel that is BS, but I have drop filled with CA (on top of sanded finish), sanded back, and applied more finish with absolutely no problems. Way easier than using finish itself to drop fill (which does not work well IMHO). The stuff is basically non-toxic, though I still wear a mask. Strongest odor is ammonia. Non-flammable. You will not blow yourself up using it. No expensive air handling (cheap box fan near cracked garage door works great). It is true that wet sanding is a bad idea. Also, do not use solvents (alcohol, acetone, etc) to prep surface between coats (water is fine). That said, alcohol can be used sparingly if you want a tacky surface between coats (say after several days). The stuff melts into its self very well. No bonding issues. Coats very well with cheap guns. And buffing is a breeze! Also, it dries within an hour or less so it can be recoated quickly. Finally, after it dries, I cannot find shrinkage. And, it remains highly repairable (indefinitely).

Negatives? Perhaps not the hardest finish, but it is hard enough for me. The darker the wood, the more likely you will see a blue cast. Thin coats help here. Some have suggested mineral oil for wet sanding, I have not tried that yet, but I will.

One of these days I might try some of that water borne varnish... but the suggested use of toxic prep materials and lack of repairability keeps me on the fence for now.

Mike

I agree that it's great stuff for all the reasons you mentioned and that it will gain popularity with other small builders as time goes on. I think that even production folks would be interested if it wasn't for the UV curable finishes. For high production rates, I think these are hard to beat.

For us small shop folks, this stuff is pretty good!

Trev

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http://www.PeakeGuitars.com

You forgot one... Easily brushes with added retarder, making it great for us small shop, no compressor guys. The first one I used it on was an electric that I play every day, and the neck still feels silky smooth

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Rob

Thanks Mike. Great to see such a positive report.
One question... anything to report re wet sanding / leveling with water?? (There have been some warnings about this, although Ultima was fine!)

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Dave
Milton, ON

I've wet sanded EM6000 with water. If you try this before the finish is cured (3 days minimum) you can run into some problems with the finish softening/blushing. Once the finish is cured out, I haven't really run into any issues with wet sanding. That's not to say I'm not conscientious about trying to minimize how long the water is on the finish...

Trev

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http://www.PeakeGuitars.com

Mike, I was wondering if the blue haze on the EIR is less than when you first finished it? Let us know if it eventually goes away.

Dave, wet sanding with mineral spirits works great. Don't know about water.

I too am very happy with the finish after about 3 months and lots of playing. I like the neck - feels as good to me as TruOil.

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Steve Smith
"Music is what feelings sound like"

I have finished 2 with Em6000 and found to have just a little less blue cast noticeable on dark woods than the USB had and about the same as KTM 9 I also have seen the same blue cast in acrylic automotive clear coat lacquer on dark color cars. I suspect this is just a trait of any clear acrylic solid. I know from experience that if sprayed to thick it is more noticeable but in truth this is such a relatively small issue in the whole scheme of things. Each finish type will have good ad bad attributes. But yet we still keep searching for the perfect finish that is hard as nails clear as glass and has no a toxins or flammability. One day maybe we will find it

I have also wet sanded both of the guitars I finished with Em6000 after 2 weeks of cure time. I had no issue with either. Now I used cool water not temped and wiped up the excess water regularly. Not allowing it to just set there for a long period. Warm water will most certainly soften any waterborne but if properly cured cool water for wet sanding should not cause an issue.

Mike, I agree with you in all but one aspect: I don't think I'll venture away from EM6000 to try one of the waterborne varnishes

I really believe the bluish cast is a non issue if the finish is kept thin. I got a call Saturday morning from the customer who purchased the mad rose OM. He called to tell me how much he loves the guitar and how much the sound has opened up since I delivered it to him a couple of weeks ago. He said he can't put the guitar down--a very good sign!! I asked him how the finish compares to his high dollar nitro finished acoustics. He said the most noticeable difference is how thin the finish is on the mad rose guitar. He said he sees absolutely no blue cast, even when compared side by side to nitro. He said the EM6000 is just as clear; however, he prefers the look of the nitro finish as it seems much deeper. But as an alternative to nitro, he said the finish I used is terrific. He commented that he wondered if the thin finish is partially responsible for how good the guitar sounds.

No complaints from me!

Ken

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http://www.casperguitar.com

My concerns with wet sanding (water) is that the sanding residue tends to clump and get sticky. This can make the process very hard to do. I have never noticed a negative surface effect. I just do not like doing it. I will try the mineral oil approach.

Mike

Mineral oil

Did you mean mineral spirits? By the way I just learned that there are odorless mineral spirits that are more highly refined to remove aromatic compounds that may be toxic to humans. I will be looking for the odorless version before my next finishing session.

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Steve Smith
"Music is what feelings sound like"

Two things,

I just took a look at a bandura that I finished last july that has a opaque black sunburst that had a very noticeable blue cast in direct sunlight over the black areas. It was in winter sun through a window and the blue case is gone or almost gone except for a couple areas where I didn't sand back the finish enough when leveling - basically on some corners that I missed when final sanding. I'll report back in the spring when we have real light out here again.

As to sanding, I use the 3M gold papers starting at 600g and going to 800g dry and they work very well. I sometimes start at 400g but I'm afraid of sand through and I always seem to have trouble getting rid of the 400g scratches. I'll usually sand for about 15 to 30 seconds and then clear off the residue on the paper and the finish with a one or two swipes of the brush. It's very easy to get in to a pattern with this. I do this over a down draft table.

After that I've been using 1000 and 2000g abralon pads dry on an RO sander. It would be nice to find a lubricant for those as they do seem to lose their grit very quickly. They still seem to continue working though.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I don't wet sand at all. I dry sand to 1000 grit then buff out. I use Menzernas 2L pre polish paste followed by their medium/light cut polish.

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http://www.casperguitar.com

Good stuff! Thanks again guys.

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Dave
Milton, ON

I had similar results as Mike when wet sanding. Made an awful mess. The whole guitar had a white haze on it that didn't start to go away until I got into the middle micro mesh grades. Tried dry on the next two, and I don't think I'll do it wet again.

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Rob

I have just finished my first guitar with EM6000 and I'm pretty happy with the results. It is Imbuia which is a fairly dark brown. Due to all of the posts I have looked hard for a bluish tint but I don't see it. When spraying if the coat was a little too thick you would see a milky blue coat on the guitar, but that was gone in an hour when it dried. I'm happy for all the reasons Mike has listed.

If you have looked through the posts on various forums, you will find some comments that wet sanding doesn't work well with this finish. I don't know, but have had no trouble dry sanding, it does not load up the paper excessively.

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David White, Toronto

"All my favourite singers can't sing."

I might be imagining it, but it seems like when I dry sand the scratches are deeper and harder to get out than when I wet sand. I have had my best results by dry sanding at first (with 320) but then wet sanding thru 1200 and then polishing/buffing.

Trev

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http://www.PeakeGuitars.com

That's why I start at 600 now. It takes a little longer to level, but the scratches come out much sooner.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

If you are using a palm sander at any point in the process, use paper with vent holes. Even if your sander does not have vent holes. The paper sill stay unloaded a lot longer and lead to a better finish.

Mike

Yes, I start with 600 as well.

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David White, Toronto

"All my favourite singers can't sing."

You might be seeing subsurface scratching as well. I found that if I used 400 grit to level between coats, three coats above it were not enough to cover the scratching. I noticed this on my last guitar. If I had 6 coats above the 400 grit, no problem. But 3 was not enough. I never use below 600 to level the final coats.

Ken

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http://www.casperguitar.com

I found this also. I started wet sanding again, takes less time to get a clean buff.

I dunno, but wet sanding this stuff can be a mess. I got good results doing it, but it sure was a PITA.

Mike

I started leveling with P800 after cure and it seemed to help with the scratches.Also a buffer is probably better than buffing by hand. I think for a small shop,this is a great finish,as it has a lot of advantages.I still love a tru-oil neck though.Maybe I`ll try 6000 on the next one.I`m sure someone will let us know how it holds up after a lot of use,like maybe a couple of years or so.
James

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James W Bolan
Nashville Tennessee

...well, its gonna take a few years. The stuff has not been out all that long.

Mike

I just recieved a coupon code from Target Coatings, JX10, good through January. 30% off. Did not say I could not share it, so I am! Not sure if you have to be a current customer...

Mike