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Rob Grant
Aug-23-2004, 5:28am
Got a recalcitrant King Billy Pine top on an f-4 I'm currently building. K.B. works a bit like North American Red Ceder, but the timber is much lighter in colour. There in lies the rub... the lightness of colour.

The tone (in the white) is great and the hours already plowed into this piece (bloody string holders!#@<g>) are long and hard. Problem is the K.B. is picking up stains and glue run from the ebony binding plus an accumulation of assorted other visual detractions (this stuff is the "sponge" of unfinished tonewoods!).

Anyhow, got a customer that's crazy about the beast and would love a "black face." O.K. folks, I'm a bloke who builds mandolins without stains (au natural) and just a thin layer of 'ol f.p. to cover and protect. Here's the question: What's a reasonably successful way to get a good looking black face? Due to the glue seep problem I doubt that I can directly dye the raw top without getting a splotchy appearance along the edges. Anybody ever mix a timber dye with f.p. and apply (after a sealing coat) to obtain a finish with good "depth." Any suggestions appreciated before I commence "reinventing the wheel."

sunburst
Aug-23-2004, 6:26am
There are probably other ways, but this should work:
Paint it black with a good quality flat black paint, then FP over that for gloss and depth.

To tell the truth, I've never tried that, but I have used black paint under varnish, and black lacquer under clear gloss lacquer. Both looked good, so I'm sort of speculating that FP will gloss over black paint as well.

Jim Hilburn
Aug-23-2004, 6:55am
Most paint stores will have tinting agents like Tint-alls.I used Lamp Black from Valspar. you just make black lacquer, and put on enough coats to get a solid color, then clear coat over that.

Bill Snyder
Aug-23-2004, 7:06am
What Jim Hilburn said. I make no claims at being terribly knowledgeable about finishing, but the only mandolin I have built so far had a tinted shellac finish. I went to a local paint store and they squirted some universal tint in a jar for me and I tinted the shellac red. Worked like a charm. Doesn't take much tint in the mix.
The same universal tints work for shellac and lacquer and several other finishes.
Good luck.

Luthier Vandross
Aug-23-2004, 4:49pm
You need a black stain...

Do you have a spray rig? You don't actually wipe the stain, you just shoot it on, sealer over that, scrape the binding, and finish.. I do a light coat, then darken it in with a second.

The other blackening method is to wash the top in a tanic bath (or 5..or 6) then seal it in a bag with ammonia... don't get the tannin on anything you don't want black. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/smile.gif


M

peter.coombe
Aug-23-2004, 6:17pm
Rob, I think you are in for a difficult time. King Billy Pine is notoriously difficult to get a decent smooth finish on it, and a black top will show up every defect. I have never done a black top in King Billy Pine, so am a little bit at a loss what to suggest. The problem is King Billy tends to form grain ridges under a finish, and when you sand it smooth, you are going to sand off the black colour. The only two blacktops I have made I used a black analine water based stain to stain the Spruce, and french polish on top of that. I don't think that will work so good with King Billy becasue you need to sand and sand to smooth out the ridges. You can see one of the blackfaces on my web site in the Gallery section.

Here is my suggestion, for what it is worth. I have had a lot of success with Target Coatings products. Get some of their Trans Tint black stain, their clear filler and their brushing varnish (all water based). I think Stew Mac sell the same products, but under a different name. Stain the King Billy and add stain to the clear filler and brushing varnish. You can dilute the stain in water or alcohol and apply it with a brush. Apply the filler and brushing varnish as per instructions. I apply the filler with a rag and brush on the varnish. I also dilute the varnish about 25%, but you can dilute it more if you want. Sand with 1200 wet/dry between coats. The filler will help smooth out the King Billy grain ridges, and the varnish goes on thicker than French Polish. Eventually after about 6 coats of varnish, you will get a reasonably smooth coat. Wait at least 10 days for the varnish to dry. Then apply clear French polish until you are satisfied with the finish. The Target Coatings varnish is for more resistant to sweat than a French polish finish, which is why I use it, but nothing can beat a French Polish. You can use the same technique on the rest of the mandolin, but without the stain. You will need to be careful with that stain not to get it on other parts of the mandolin, it is powerful stuff. Messy job, blackfaces. I don't like doing them.

Luthier Vandross
Aug-23-2004, 9:53pm
Hide the grain? My God, WHY!?

You'll never hear of a 'vintage thick finish'.. oops... maybe in a few years.

;)

M

Michael Lewis
Aug-24-2004, 12:11am
That's funny Miles. http://www.mandolincafe.net/iB_html/non-cgi/emoticons/laugh.gif

Rob Grant
Aug-24-2004, 4:20am
Thanks for all the excellent replies concerning black face techniques.
....................
Peter, I sure do like the tone of K.B., but the stuff is difficult for me to deal with. Thought it might be my own "wood butcher" ways, it's good to hear a confirmation that I'm not alone. I didn't really have this much trouble with the last little flattop I built with K.B., but this first attempt at an f-4 strap hanger is hell... should have used spruce.

Anyhow, I'll experiment with a few K.B. scrap bits that I have around the workshop and see what looks the best. Our panel beater at work even suggested blowing a coat or two of gloss black, two-pac automotive paint on the sucker. I'll give that a miss, as it would be about the same as eliminating the timber and just lay a few layers of glass mat and resin with a nice gel coat black!<G>

peter.coombe
Aug-24-2004, 6:35pm
Rob

A couple of extra things I thought of on re-reading your original post. King Billy certainly is a bit of a sponge for fingerprints and dents and dings. I always give it a coat of blonde shellac as soon as I finish carving the outside. That at least stops the fingerprints. I don't understand why you are getting bleeding of colour from the Ebony binding and the glue, I have never had this problem, although I have made a few King Billy tops with Ebony Bindings. What glue are you using for the bindings?

The other thing I have discovered is that it is essential to seal the King Billy with shellac before applying any other finish. Thus I always give it a good coat of shellac before applying the Target Coatings filler. If you don't do this, it will go all blotchy, and you are faced with a lot of careful sanding to get rid of it. Even then, sometimes it is difficult to avoid a bit of blotchiness. Spruce is completely different in that it is best to apply the filler first before the shellac. Anyway, I can now get a really nice smooth finish on King Billy Pine, and the natural color is really good on it's own, so I think I have overcome most of the problems. Some of my oval soundhole King Billy mandos have been really stunning sounding. They blow away all the Spruce topped mandos in the sound department, so the effort in the end is worth it. The only remaining problem is that the wood is somewhat variable, prone to hidden knots etc, so the quality of the sound does vary more than with Spruce.

Good luck with the strap hanger, no one has offered me enough money to tempt me to tackle one of those yet.

Rob Grant
Aug-25-2004, 3:23am
Peter,

Thanks again for the hints on K.B.

I'm using a locally availiable super glue (Selleys-clear). I used it with the last K.B. mando I bound with ebony without any drama. The end grain is sucking the stuff up and making the timber near the binding a slight "orange" colour. In reality, the more I look at it, the less of a problem it seems. Once I scrape the bindings and run a coat of blond, I reckon it will disappear. I have had problems in the past with final sanding on the K.B.-ebony combo. The black dust from the New Guinea ebony would sometimes embed in the nearby K.B. and give the recurve a "dirty" look. Time and use eventually evened the top out, but it was a bit disconcerting.

About those strap hangers... If I ever finish this sucker, I doubt I'll ever try another. The f style surely looks good, but it is hardly worth the extra hours when it comes to what my local market will pay. If you're into the "hair shirt" and walking barefoot on broken glass, give it a go!<G>

sunburst
Aug-25-2004, 7:54am
About those strap hangers... If I ever finish this sucker, I doubt I'll ever try another. The f style surely looks good, but it is hardly worth the extra hours when it comes to what my local market will pay. If you're into the "hair shirt" and walking barefoot on broken glass, give it a go!<G>
http://www.mandolincafe.net/iB_html/non-cgi/emoticons/laugh.gif http://www.mandolincafe.net/iB_html/non-cgi/emoticons/laugh.gif http://www.mandolincafe.net/iB_html/non-cgi/emoticons/laugh.gif

peter.coombe
Aug-25-2004, 7:18pm
Rob

Black dust from Ebony bindings is always a problem, King Billy or Spruce. Probably worse on Spruce. You just need to change the way you sand the top so you are always moving the sandpaper towards the bindings or along the bindings instead of from the bindings to the top, and make sure the sandpaper is clean. Rounding the bindings slightly so they are just shy of the top helps. I think using a different glue will solve the bleed problem.