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Now that's the truth! Wet sanding this stuff (EM6000) results in an icky mess, and any pores with fill with the wet particulate and then harden to a white color. Not good.

I don't remember who recommended it but wet sanding EM6000 with mineral spirits works great. I used maybe 1/2 cup in a bowl.

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Steve Smith
"Music is what feelings sound like"

Randy, thanks for the great information! Would you mind sharing your finishing schedule? I picked up on the epoxy and two coats of sealer. Do you sand the epoxy to the wood? Are you using the Waterlox tie coat? Can you tell us what you do with the KTM-SV?

James, and anyone else interested,

You can get Randy's detailed description of his finishing schedule in the following thread:

http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=22737

My thanks to you too, Randy, for sharing this.

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-Clint Beacock

Love to try the KTM-SV! Any sellers in Canada??

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Dave
Milton, ON

James,

I don't use Waterlox. I tried it once and didn't like it. I've done the sealing/pore filling thing two ways.

One, I've pored filled on the bare wood with epoxy (I use System 3 - SB112) and kept a thin coat on everything (not the top). I then put two coats of sealer on top of everything. I still feel safer using the sealer over everything. I let the sealer dry 2 hours between coats and before finishing. The manufacturing recommends allowing the sealer to dry between 2 and 4 hours. After 4 hours, they recommend sanding it for adhesion. I go two hours and don't sand, although it does raise whiskers on the spruce that I knock off.

Two, I put a coat of sealer on everything first to wet the wood, followed two hours later by pore filling. In this case, I don't worry if I sand through the epoxy to the wood. I then continue with the two coats of sealer after pore filling.

I spray every 1.5 hours and I get about 0.5 mills per coat once dry. I have good air circulation/ventilation both during spraying and curing. If you shut your fan off after spraying, you may want to allow 2 hours between coats. I spray my first set of coats on day one and then sand everything flat the next morning with P600 and continue spraying my second set of coats. Two days later (36 hours or so), I level sand with P1000 dry and then wet sand with P1500 and then P2000. I buff on the sixth day. I use Carborundum Premier red paper for the dry sanding. Awesome stuff. I shoot for about 4 mills on the top and 5-6 mills everywhere else.

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

This sounds great. I think it will solve the finish dilemma for me. I have been using Rick's finish process, but it's a little cumbersome for one guitar at a time. It's great that you're getting good adhesion with just the finish over the sealer. That eliminates another step/product.

Mike - if this comment has already been responded to - forgive me - it's a long string. I hear you on the explosive part - I can't spray nitro either, given my spreaying setup. But I'd caution you to make any assumptions about the toxicity of waterborne lacquers. I've used KTM 9 - and was warned by some very experienced luthiers to use precautionary spraying methods as if it were nitro as per toxicity - respirators, good venting, etc. I was spraying in my basement with the window open essentially, and was warned that I was looking for trouble. It's probably "safer" - I just wouldn't assume that it is "safe". Regards,

Mike,

What Corky said is correct. Waterbornes contain a number of cosolvents that aren't as volatile as solvent based finishes but still should not be inhaled as either mist or vapor . Even though they are probably less toxic, they are in fact more bio-available due to the fact that they are water soluble and can readily dissolve in biological fluids. I take the same precautions that I would take if I were spraying nitro, except I don't need to be explosion proof.

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

Thanks Corky & Randy. I do use powered ventilation and a respirator. I take nothing for granted. I just do not want to deal with explosive stuff, but I do love the look & feel of nitro.

Mike

Randy, I hope you don't mind another question, this time about your bridge gluing method. Have you always drilled your bridge pin holes through the top before gluing the bridge on, or is this something you started doing when you switched to using CA on top of the finish? What advantage(s) do you find in drilling the holes through the top before gluing the bridge on?

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Todd,

I didn't always drill the pin holes first, but I have been doing it that way for a long time before I started using CA to glue the bridge. I just find it easier to drill the holes and make the notches for the strings without the bridge on. After I glue the bridge down, I just need to do a little reaming and filing of the string notch, mainly to clear out any glue, and I'm done. I also notch my bridges before gluing them, which I find much easier than doing it on the guitar.

Nice start on the website! Very clean and elegant. I like it!

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Randy Muth
RS Muth Guitars Website
RS Muth Guitars Blog
Facebook Fan Page

Thanks, Randy. And thanks for your feedback on my new web site, too. Much appreciated.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/