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View Full Version : How to make black top ukulele ?



tangimango
10-13-2013, 03:40 AM
http://www.youtube.com/watch?v=ayZHyiR1cuQ

how does one make a spruce top like this one black.
process in doing it?

i have black water base stains and dyes.

gyosh
10-13-2013, 04:03 AM
Mine is a Compass Rose. You can PM Rick, maybe he can help you out.

59766http://www.ukuleleunderground.com/forum/attachment.php?attachmentid=59766&d=1381672940

Sorry about the pic, it's the only one I had on my iPad.

Timbuck
10-13-2013, 04:06 AM
Use black enamel paint :D

Michael N.
10-13-2013, 10:12 AM
It's basically an Ebonised finish. This goes way back to the early 18 th century when the martin brothers were trying to emulate Japanese lacquer. I've done it with Shellac, staining the wood first and then applying a 'Black' Shellac on top. You build sufficient coats that you can rub back, flatten and polish to a very high gloss. The same can be done with other types of finishes - using a Black dye to tint. I assume that's what Steinway do. I'm almost certain that they are spraying, probably something like nitrocellulose.
It's a very labour intensive finish. Nothing like glossy Black to show all the defects. . . and the fingerprints.

Skinny Money McGee
10-14-2013, 01:29 AM
Last time I mentioned Campbells Lacquer I was heavily flamed here in the Luthiers lounge, but they will mix any color you want, including black. I've had them mix custom colors for a few different projects. After filling, lay down a base coat and shoot clear over it.

I think many of the builders here use Cardinal products. You can have those tinted to any color too. Just 3x more expensive.

Chris_H
10-14-2013, 05:21 AM
Campbells black lacquer stays soft for too long. With Campbells it helps to lay out thin coats and really let them cure before proceeding. Personally, I would not use it on an instrument.

I do black lacquer finishes using Chemcraft wash coat tinted with industrial tints, thinned about 200%-300% with acetone, then clear lacquer over. It works over metal or wood without primer, basically sticks to anything. I have been doing it this way for about the last 15 years, and am super happy with it. It is very versatile, friendly, and forgiving. The black layer is incredibly thin, so I can see it being great for an instrument finish. Also, it is tough as nails. The chemcraft wash coat dries flat, in seconds usually. You can spray to completely black in a few minutes, then start clear shortly after.

I would be curious to know how Rick did that finish, and especially curious to see his process for clean lines on that rosette. Something tells me that wasn't an entry level finish.

Black automotive paint works well for black.

The transtint dye, first applied to the wood, then in the clearcoats, I have never taken it to fully opaque, but it has a slight purple cast.

Really important to get the substrate sanded completely smooth, so when sanding or rubbing out, high spots do not become spots that need to be touched up with black.

gyosh
10-14-2013, 05:41 AM
The rosette is a sticker.

The finish is polyester.


(that's about all I know about it)

Chris_H
10-14-2013, 05:47 AM
that makes sense. I wondered if it might be a sticker, Otherwise, that is some highly specialized trickery

Moore Bettah Ukuleles
10-14-2013, 08:29 AM
Would the purfling and binding be taped off first? Seems rather tricky.

Chris_H
10-14-2013, 08:45 AM
I would guess.. that is where I would start. it might be useful to carefully seal the edge of the tape with a clearcoat to prevent bleeding into the purfling.

hawaii 50
10-14-2013, 08:49 AM
Email Rick Turner...he is very helpful,when you have any kinds of questions regarding building or repair of instruments....

Gary... one of the nicest finishes on a CR yet!

Skinny Money McGee
10-14-2013, 09:44 AM
Would the purfling and binding be taped off first? Seems rather tricky.

Gibson Custom shop sprays the entire body, then with a sharp scraper gently scrape the paint/stain off the binding, then clear coat.
http://www.gibson.com/en-us/Lifestyle/video/Making%20Of%20The%20Gibson%20Cust%20%2812%29/

Never had a drying problem using Campbells in the 15 years I've been using it. They make a Nitro that can be colored or tinted as well.

Chris_H
10-14-2013, 10:37 AM
you spraying clear Campbells? that stuff is fine, though it is not my first choice in clear nitro, for anything. I was not speaking of their clear, I was speaking of the Campbells black pigmented lacquer. It has the word 'black' on the can. It is a very heavy bodied, high solids nitro based lacquer. Because it is such a high solids product, it takes a long time, (months in my experience) to fully shrink back. It can be handled quickly, as with other lacquers, but is not fully cured. That is my experience. I have used it several times (different batches) and my application was not at fault, nor in too cold of an environment.

I have sprayed a LOT of Magnalac

thistle3585
10-14-2013, 10:38 AM
I have used a solvent based spray paint then clear coated it but have found the lacquer will separate from the paint easily. I now use tinted lacquers from reranch. You can buff them directly or shoot a couple clear coats over it. On binding, I seal the body, mask the binding, shoot a couple coats of color, remove the masking, scrap the bindings then spray clear coats. For some reason red tends to bleed a lot worse and I end up having to spot scrap the binding. On wood bindings, I use multiple coats of shellac. You are scrapping the tint off the sealer not the binding.

Chris_H
10-14-2013, 10:45 AM
If you were scraping, could you also scrape the shell clean? I can see scraping just a binding clean, with a slight angle off of flush with the top, but to scrape the binding, plus the shell purfling, plus the likely BWB or similar strip, then the angle goes closer to parallel with that of the top. At some point it would be easier to mask, no?


Gibson Custom shop sprays the entire body, then with a sharp scraper gently scrape the paint/stain off the binding, then clear coat.
http://www.gibson.com/en-us/Lifestyle/video/Making%20Of%20The%20Gibson%20Cust%20%2812%29/

Never had a drying problem using Campbells in the 15 years I've been using it. They make a Nitro that can be colored or tinted as well.

Skinny Money McGee
10-14-2013, 12:30 PM
you spraying clear Campbells? that stuff is fine, though it is not my first choice in clear nitro, for anything. I was not speaking of their clear, I was speaking of the Campbells black pigmented lacquer. It has the word 'black' on the can. It is a very heavy bodied, high solids nitro based lacquer. Because it is such a high solids product, it takes a long time, (months in my experience) to fully shrink back. It can be handled quickly, as with other lacquers, but is not fully cured. That is my experience. I have used it several times (different batches) and my application was not at fault, nor in too cold of an environment.

I have sprayed a LOT of Magnalac

I've never sprayed the "black label" stuff. Didn't know it existed. The place I would go, they would catalyze it and pigment it to what ever color you wanted, much like a paint store would. Magnamax and Magnaklear non yellowing UV resistant clear coat with colored finishes, and just Magnamax shooting plain clear. I would buy the Magnamax clear in 5 gallon cans, and the pigmented by the gallon. They also make nitrocellulose and polys which I have not used before.

Cardinal's website says they will mix you any color as well including metallics.


Here's a better video from Stewmac about scraping color from binding. http://youtu.be/TNbsZsSabPs No idea about the shell. A synthetic would probably scrape well.

tangimango
10-14-2013, 01:45 PM
I will dry a water base black dye then try mix dye with truoil.

Chris_H
10-14-2013, 02:35 PM
try it on a sample first. My experience with using oil as a vehicle for color is that some color is delivered on the first coat, much less on successive coats.

How black do you want it Tangimango? What are you trying to accomplish? Like the Compass Rose shown above, but with Tru-oil?

If you want it black like that compass rose, I think dyes might be difficult with an oil finish. And... will the dye yield the correct color black?

Just brainstorming.. but If I were trying for black, and an oiled finish, I might use a black oil enamel thinned a little, maybe 50/50 as a 'stain. A little Japan drier added. Sand the wood really smooth first, like 1000 grit, blocked. I would try it first to see how it looked, are you talking spruce top? I would not use a spar enamel, but would use a gloss. If you need any more black, then maybe the tru-oil would add just a teeny bit more black. Oh, wipe the black paint/ stain off a couple minutes after application.. With a thin wood such as an uke top, careful about too much saturation, and soaking through to the interior. After this dries, you can oil away...

at least one way to skin a cat..

pakhan
10-14-2013, 05:53 PM
There are also gunpowder blacken tops...

tangimango
10-14-2013, 05:54 PM
yes i will experiment with scrap wood peices. i have some englemann and sitka scraps.
thanks for the info everyone.


try it on a sample first. My experience with using oil as a vehicle for color is that some color is delivered on the first coat, much less on successive coats.

How black do you want it Tangimango? What are you trying to accomplish? Like the Compass Rose shown above, but with Tru-oil?

If you want it black like that compass rose, I think dyes might be difficult with an oil finish. And... will the dye yield the correct color black?

Just brainstorming.. but If I were trying for black, and an oiled finish, I might use a black oil enamel thinned a little, maybe 50/50 as a 'stain. A little Japan drier added. Sand the wood really smooth first, like 1000 grit, blocked. I would try it first to see how it looked, are you talking spruce top? I would not use a spar enamel, but would use a gloss. If you need any more black, then maybe the tru-oil would add just a teeny bit more black. Oh, wipe the black paint/ stain off a couple minutes after application.. With a thin wood such as an uke top, careful about too much saturation, and soaking through to the interior. After this dries, you can oil away...

at least one way to skin a cat..

thistle3585
10-15-2013, 03:43 AM
One way to help with a good clean line is to use a piece of black .010 binding between the purfling and body. Then you just need to scrape back to that binding and you don't risk getting in to the top. I like sealing the binding with several coats of shellac so I don't have to scrape the binding away.

Pukulele Pete
10-15-2013, 03:56 AM
I didnt build a uke but I painted my Mainland red cedar concert . I wanted a black top uke. I sanded the top and masked off the rope style purfling/binding? and I used black lacquer from a can and then clear coated with clear lacquer , wet sanded and buffed . It has been a few years and it still looks fine. I only sanded the top enough for the lacquer to stick , I was worried about the compatability of the original finish ( not lacquer,maybe some poly ) but it stuck fine.

Rick Turner
10-21-2013, 03:07 PM
The one pictured...which I sprayed...was done with the following:

Two coats of Smith CPES as a pre-sealer
Two very thin coats of Simtec Adhesion promoter
Three thin coats of Simtec polyester sanding sealer sanded dead flat. Masked off the purfling with 3M blue fine line tape. Masked off the rest of the instrument
Two thin coats of Simtec adhesion promoter with black MEK soluble dye added. Remove tape at two hours cure. Allow to cure no more than about 14 hours. Carefully scrape where needed
Three thin coats of Simtec polyester top coat.
Allow 48 or more hours for full cure. Sand with 600, 800, 1000, 1200, and do final buff with two different Menzerna compounds on 14" buffing wheels.

Final finish thickness is around .006"

All polyester coats cured with 2% MEKP.

Spraying done with Sata HVLP conversion guns, and NR95 for all the polyester and a Mini-Jet for adhesion promoter and color, both guns using the 3M Paint Preparation System of disposable cup liners; all work is carried out in a fully legal 8' x 8' spray booth. I wear a Tyvek suit, wear a ski-mask style head covering, and use a two stage respirator with chemical rated cartridges.

I do this...with or without the color coat stage...on about 6 to 8 instruments a week now. Some finish schedules are a little different, for instance with the rubbed look sunbursts, for instruments on which I stain the wood directly, and on those where I do a satin top coat.

Don't try this at home...you just can't get the kind of results that professional finishers can get in any reasonable amount of time with products that are for the home market. Also, the materials we use are pretty nasty in their liquid and atomized spray form. With modern catalyzed or UV cured finishes, you also avoid a lot of the issue of finish sinking into the grain that you get with solvent based finishes. And yes, there is nothing as difficult as black. It shows everything...

Chris_H
10-21-2013, 04:50 PM
Thanks for that Rick

Chris_H
10-22-2013, 09:30 AM
That was perfect timing.. Just spoke with Simtec, will be using their polyester system on some upcoming 4 solid body electric builds (2 of mine, 2 for a good friend who will be building with me). A little more durability and the ability to rub out and polish within a week are the reasons why. The standard cure, not the UV cure. Still nasty stuff, not a DIY finish. I have a spray booth with positive pressure clean air, explosion proof spray booth fan, and an air supply respirator.

It will be interesting to see how this stuff sprays.

Rick Turner
10-22-2013, 11:40 AM
BTW, I did not write in all the scuffing and sanding between coats.

Lightly...very lightly sand the CPES to knock down any nibs.
Scuff the Adhesion Promoter using maroon ScotchBrite.
Sand the Simtec poly sanding sealer dead flat to 320 before color.
Do NOT sand the color unless you go past 16 hours cure, and then only scuff with ScotchBrite.

There are timing issues and thus adhesion issues when spraying one material on top of another. If you catch the cure window just right, they'll bond. If you don't, you'll need to scuff.

Chris_H
10-22-2013, 02:29 PM
Rick, do I recall that you sometimes use a UV cured filler? Is it a simtec filler? What is a good pore filler for tinting that will not shrink back?

L'Ukes Lutherie
10-23-2013, 07:48 AM
...or this?

http://www.ukuleleunderground.com/forum/attachment.php?attachmentid=60121&d=1382543348

The cigar box was painted black -with prominently raised grain- when new. I heavily modified the innards but didn't alter the existing finish. I just touched up the dings with a Sharpie, and french polished the heck out of it. The blond shellac adds considerable transparency and warmth to the overall effect. So, in short, simple paint and polish will work. That said, shellac is notoriously soft. One need not look too closely to notice that I have since pretty well banged up the edges, but hey -it was junk when I picked it up....

So I guess someone should let OldePhart know that indeed it is possible... and indeed it is all the more noticeable, having done so.

Rick Turner
10-23-2013, 06:57 PM
I value the quality of a finish not by how it looks going out the door...that has to be near-perfect no matter what, and you can achieve that with a lot of different approaches... But how will it look in six years of regular playing? And, as a pro luthier, I have to ask myself, how much time in man-hours does it take to achieve great results, and how many days does it take to spray, sand, cure, and rub out? I've done black French polish, and I won't do it in the future...

Chris_H
10-23-2013, 07:17 PM
One of my friends just sent to me, what I am told, was a guitar started by Steve Cripes before he passed away, and then finished by Resurrection Guitars. I think it is around 20 years old. It has been played, and there is evidence of slight movement in the wood, nothing that wrecks the finish except for over a thin slice of Ebony just under celluloid bound fretboard (probably caused by water based glue or not as likely, not properly seasoned 2mm thick Ebony) The finish is cracked up here if you look closely, not ugly. The finish of the guitar is great overall.. pretty cool...

Skrik
10-23-2013, 09:08 PM
Does nobody use the tea/ iron filings/ vinegar method any more? Getting the wood itself to change colour renders the discussion of thickness moot.

Kevin Waldron
10-24-2013, 05:07 AM
Rick,

Are you curing the UV coats with a UV Light? ( I don't understand the long wait times if you are ). Do you have a portable UV light or booth?

We've never used Simtec products..... only old McFadden/Seagrave and Cardinal for instrument finishing..... ( tried a lot of others but didn't like them )

Blessings,

Kevin

Rick Turner
10-24-2013, 02:28 PM
I don't see the point in UV cure unless one is making so many instruments that cure time-to-rub out is really a bottleneck...and it was Bob Taylor who told me that he didn't think the investment in a UV booth was worth it until building about 200 guitars a month. We can sand for a re-coat with overnight cure; we can sand and rub out with a 36 to 48 hour cure. Who here needs to finish faster than that? And I just don't want to hassle with putting on a UV proof suit and eye protection to use a UV wand. It's amazing...and quite un-needed in my operation. I'm making about 25 instruments a month right now. I'll reconsider if I hit 50 a month, and I hope to be retired before that happens!

UV has been totally oversold in the small boutique lutherie world. It's so razzle-dazzle that luthiers get seduced by the magic and don't stop to consider how fast you can do catalyzed finishes. I did a finish start to rubout on my own guitar in three and a half days. For whom is that not fast enough? There is none of the pore sinking that you'd see with even two weeks cure after a week of spraying and sanding on nitro. There is some anecdotal evidence (Tom Anderson...) that UV cured poly is not quite as hard and durable as MEKP cure; he does a "dual cure" on a lot of his finishes...he adds 1% MEKP to UV cure polyester. That does mean he has to use a conventional HVLP gun, not have the poly pumped from a 55 gallon drum as is done at the big factories, and I think that the real reason that some of the big guys use UV is because they can just pressure feed the poly to the gun through a hose and never have to deal with cups and cleaning the guns after spraying. Just hang up the spray gun at night, and keep spraying the next day. That also makes for a much easier to handle spray gun...I'll tell you, my arm gets tired after a day of spraying. Don't have to go to the gym, though...

The Simtec products beat the McFadden/Seagrave stuff right off the planet, and Cardinal doesn't have a poly sanding sealer...yet... I tried the Cardinal isolator urethane and hated it...bad adhesion with the Simtec poly. I love their nitro satin lacquer, though, and Addam Stark loves the gloss nitro that he shoots here in my booth.

Kevin Waldron
10-25-2013, 02:52 AM
Rick,

Thank you for the detail. ( We have a UV light and have not been happy with the overall results.... and the products we have tried. ) We have toyed with catalyzed varnishes and have liked these finishes somewhat better. Since we have changed gears as to what we do and sell with the parts, pieces, templates, materials, etc. we haven't had time to build complete instruments but would like to pick this back up soon if the economy will levels back out to a steady growth and allow us to hire some additional help.

Thank you again and good to see you back in the discussion.

Blessings,

Kevin

Rick Turner
10-25-2013, 12:01 PM
Staining wood black does not give the same results as using an opaque black finish. It's nice, it's old-time, but it's not the same solid black look.

I used to use pre-catalyzed varnish when I was in the cabinet biz. Catalyzed urethanes and polyesters are a whole 'nuther thing, though.

The problem with UV pore filler is that you have to make sure that the UV light actually penetrates down into the pores or you get cured near the surface, and uncured below. I still think that UV only makes sense if you're at the scale where you have a full time finisher and are really cranking stuff through. At this point, I'd be more inclined to think about designing a semi-automatic flat surfaces buffing machine...buffs on a mandrel with a motorized shuttle underneath moving a uke or guitar back and forth while turning the instrument about 15 degrees per run through. Stack buffs to about 3" to 4" wide and have an XY table underneath with a rotating table, too, to hold the body.

Chris_H
10-25-2013, 12:14 PM
Ok.. for some reason I thought you were using UV cure. I notice simtec has a polyester? pore filler that looks like it can be tinted. I will look into that. I am just now finishing an uke with black tinted pore filler on some light colored Brazilian Rosewood. I sealed it with a light coat of shellac first, but I did not trust that it was fully dried/ shrunken. 5 months later , I just cut it flat and polished it. Fingers are crossed that it is done shrinking. I wont do that again.. gotta find a better product, which is why I was asking about a good filler that can be tinted to a deep color like black, that wont shrink, cures quickly, and is somewhat easy to use.

Rick Turner
10-25-2013, 01:40 PM
1) I have consistently said that I am not using UV, I'm catalyzing both urethane isolater/sealers...that stuff is 1:1, and I catalyze pre-cobalted polyester with about 2% MEKP. A convenient rule of thumb is that it works out to just about 1/2 cc per fluid ounce of material.

2) If you want to guarantee poor cure of UV polyester pore filler, then tint it! Tinting blocks UV quite effectively, so you'll get a bit of cure right at the surface, and uncured material down in the pores. Also, you simply must use an isolater between rosewood and polyester. The oils in rosewoods...all of them...as well as other woods like Western red cedar act as an anti-catalyst for the polyester. Polyester simply will not adhere or cure in the presence of these oils, and you can forget about acetone wiping, etc.

I'm telling you, Smith CPES epoxy, decent cure, Simtec adhesion promoter (which is basically the same as an isolater), then polyester build coats, and then whatever...nitro satin for quick, nitro for that easy buff topcoating, urethane for tougher than nitro but easier to buff than poly top coats, or poly top coats for an incredibly tough high gloss finish.

BTW, some of the disasters with poorly cured polyester don't show up for quite some time whether it's UV pore filler or what's directly on the wood. Addam Stark just got in a refin job on an early polyester Taylor...yeah, Bob learned the hard way, too. There's nothing quite like a finish that is hard on the surface and is jello underneath. I would not trust UV pore filler cured any way other than in a full-on UV booth, and it better have urethane underneath. And if you're using oil based pore fillers, you'd better let that stuff cure well before locking in the solvents under urethanes or polyesters or nitro lacquer. I'd say let the traditional pore filler dry for at least two or three days before shooting anything over it unless you really like that sunken pore look.

And who can let a finish cure for 5 months? Not me! I can't handle 5 weeks or even 5 days! And I don't have to.