Stew Mac Water-Based Varnish

[Jim Webster]

I thought I saw a thread on this before but I couldn't find it using "search," so if this has been covered please point me in the right direction.

I'm using the Stew Mac waterbase brushing varnish for the first time. This is my first instrument building project -- a lap steel guitar actually, but my next one will be an electric mando. I figured I'll make my mistakes on something fairly easy before working my way up to an acoustic mando. Has anyone else used this waterbase brush-on varnish -- and if so, do you have opinions or recommendations?

I've more or less followed the directions on the grain filler and varnish cans, but have also taken some liberties. The varnish directions say that after doing a couple of coats dilluted with 50% water and sanding with 320 grit to then do 3 coats undilluted, sand with 320 grit, do another three coats and sand with 800 grit. However, I wasn't happy with the texture of my first three coats of full-strength. The varnish seemed way too thick to me and. Therefore after sanding with 320, I've just done another three coats, but with the varnish dilluted with 25% water. This has given me a much smoother texture, which I'll sand down with 800 grit one evening this week. I'll then do a couple of final coats, but think I'll go with the 25% dilluted for these too - after which I'll let it cure for a couple of weeks and then wet sand with 800 and polish with coarse, medium, and find compound.

Am I risking premature wear and tear by using the dilluted varnish? If I was spraying wouldn't it be dilluted anyway? Based on how this looks so far, I think it will look pretty good when done, but does this waterbased varnish hold up over the long run?

[labraid]

I don't know much about water based varnish, but a greater quantity of thinner coats are always stronger than a few thick ones... You probably done did the right thing http://www.mandolincafe.net/iB_html/non-cgi/emoticons/smile.gif

[toddjoles]

I must have put on 40 coats put on according to directions and still couldn't get it to look good. #
So I sanded it down and started over.

I sealed with the recommended cut and did not thin my varnish for m y top coat.

After 12 coats there was no change from before. #After sanding I was wiped it off with a rag. #I accidentally used a rag that had some denatured alcohol on it and that did the trick. #The denatured alcohol had softened the varnish just enough to let it flow out.

I added 3 more coats, sanded, wiped and then rubbed out with micro mesh then gave it one last wipe down with the alcohol. It came out beautiful.

[Jim Webster]

Thanks for the reassurance -- and the tip about the alcohol. I hope this doesn't mean no one can ever spill a beer on this when it's done.

[toddjoles]

Beer would be fine, but like always it's the hard stuff that will mess you up.

Seriously, it set up fine and has hardened nicely. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/mandosmiley.gif

[Dru Lee Parsec]

Reminds of something my grampa once told me: "What's the difference between a violin and a fiddle? You try not to spill beer on a violin."

[Dfyngravity]

i am thinking about using this product too. does anyone have any pictures of the outcome? i would love to see them. and if possible some clear directions of use since the directions on the can don't seem to work. i would greatly apreciate it.

[Jim Webster]

I just finished my lap steel -- other than soldering in the electronics, which I hope to do tonight or tomorrow. The finish came out absolutely GREAT - way better than I'd expected with a brush-on water-based varnish. I can't post a picture here because its not a mandolin but I can e-mail you some pictures. To avoid publishing your e-mail address you--and anyone else who is interested--can e-mail me at my "web-safe" e-mail address [one that I can torch if it starts generating piles of spam]:

jwebster-dawg6516@mailblocks.com

I'll partition off a section on my wife's business web site soon and post some pictures.

I'll post another message below with my application procedure.

[Jim Webster]

Here's how I applied the Stew-Mac water-based varnish.
I sanded the wood down with 320 grit, wiped clean with naptha and then put on two coats of grain filler a couple of hours apart. I hung the body from a ceiling hook to dry between coats. The next day I scuff scanded with 320 grit as directed and also leveled out a couple of small drips.

Next I put on two coats of the varnish dilluted to 50% with Stew-Mac stain mixed for a medium brown color (I used the water-based stain at a ratio of about 1 0z per quart - though obviously in a much smaller batch (1/8 oz in about 1/2 cup of stain -- but the mixing and color would depend on your color choice). These coats were a couple of hours apart.

The next day (the following weekend)I began applying full-strength varnish as directed (also with stain mixed in)but after doing the first coat, I decided it was way too thick. I sanded that coat down to eliminate brush strokes and to restore a thin level surface. I then did all the remaining coats with a mixture of 75% varnish, 25% water. This went on in reasonably thin layers that flowed out with minimal irregularities or brush strokes. So using this mixture I did two addional coats (on top of the now sanded full-strenghth coat). The next day I sanded again with 320, including very carefully sanding the few small drips. The edges where the side meets the top and back need a bit of careful attention because the brushed-on varnish tends to form a a ridge along the edge. I carefully sanded these down flush with the rest of the varnished surface.

The next day (again the following weekend - but if I didn't have a day job I'd have done it on the next day)I put on three coats of clear varnish (with no stain mixed in) dilluted with 25% water. I did these about 2 1/2 hours apart. After letting this dry overnight I level sanded with 800 grit paper (as directed) and then put on two more coats of clear varnish also dilluted with 25% water.

I then let the varnish cure for three weeks and in the meantime finished the fretboard, shaped and filed the nut etc. After three weeks curing, I wet sanded it smooth with 800 grit. I stopped frequently and wiped it down with clean water to spot any irregularities in the finish. The wet sanding will make a white paste as you sand. After wet sanding I washed it down with clean water to remove the paste residue. The finish had a dull satin appearance.

Finally I buffed using using coarse, medium, and fine buffing compound (also from Stew Mac)in succession. I used a random orbital buffer (about $25)and a separate buffing pad for each grade of compound. The end result is a deep high-gloss finish.

[lownote]

Dfyngravity
am thinking about using this product too. does anyone have any pictures of the outcome? i would love to see them. and if possible some clear directions of use since the directions on the can don't seem to work. i would greatly apreciate it.

Here you go.

[lownote]

And of course the back. I applied maybe 10 coats mixed 50/50 with color tint in the first 3 or 4 coats. Let it cure for a couple of weeks then rubbed it out.