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davidrboy
12-19-2014, 07:07 AM
I was recently given the following advice by a highly respected builder (thsi is for my first uke, which I just finished assembling and sanding):

"I use a wipe-on polyurethane finish. Itís an oil finish as opposed to a solvent finish like lacquer. The major difference between the two is that the oil finish soaks into the wood and lacquer does not. Both finishes will produce the same look.

Here are some tips that might help:

Sanding scratches and glue residue will show after applying the finish, so itís important to scrape glue off the surface and sand thoroughly. You can still remove remaining glue and scratches after the first coat of finish is dry.
Wipe on 2 liberal coats a day apart, sanding between coats, then one final light coat.
Smooth with fine steel wool after final coat is dry and buff with cotton rag."

It all sounds like solid advice to me. And I really like the matte finish on said builder's ukes.

Can anyone recommend a great wipe-on poly for this application? Or share thoughts, experiences, comments?

Thanks in advance.

rudy
12-19-2014, 10:14 AM
It's all about prep.
Never expect any finish to look better than your in the white instrument.

I use three coats of Min-wax wipe-on satin poly applied 12 hours apart for almost all of my instruments and you'll get a professional level finish if your application technique is good.

I used it exclusively on over 100 lap steels when I did custom instruments and was always happy with the results.

As long as you're meticulous about cleaning any dust off between coats (DO use a tack rag just before application) then you'll have no need for the 0000 steel wool rub-out. That actually makes things far more difficult. Occasionally you might need to lightly hit any area where dust remains on the completed surface, but JUST A LIGHT RUB.

Titchtheclown
12-19-2014, 02:25 PM
A tip when doing porous woods like pine or meranti is to do a second coat not long after the first as large areas of the first coat will have all but disappeared.

jcalkin
12-19-2014, 03:27 PM
Min-Wax wipe-on satin poly is the stuff, like Randy said. I like it best over pore filler, as open pore finishes often look too dry to me. Also, there will be no soaking in of the poly into the wood. Lacquer would probably soak in just as much as poly if it didn't set up so quickly. You could also sand in the first coat of poly over unsealed wood with 320 wet-or-dry, which helps fill the pores somewhat. This works great for me on mahogany. On rosewood, not so much. I like a satin finish, but the application technique might have to vary with the wood type.

Doc_J
12-19-2014, 05:25 PM
For much of the nicer furniture I have built I have used the wipe-on Min-Wax, satin poly with great results, too. It usually works better for me if I use a sealer/conditioner first, which raises the grain and yields more even color if you have any stain in the poly. I have used this primarily on oak with some light color in the poly to warm the pale oak color.

Did you also consider Tru-oil?

Beau Hannam Ukuleles
12-19-2014, 05:44 PM
Min-Wax wipe-on satin poly is the stuff, like Randy said. I like it best over pore filler, as open pore finishes often look too dry to me. Also, there will be no soaking in of the poly into the wood. Lacquer would probably soak in just as much as poly if it didn't set up so quickly. You could also sand in the first coat of poly over unsealed wood with 320 wet-or-dry, which helps fill the pores somewhat. This works great for me on mahogany. On rosewood, not so much. I like a satin finish, but the application technique might have to vary with the wood type.

John- Can you spray nitro over the Min-wax poly????

Chris_H
12-19-2014, 05:47 PM
Technically you are not supposed to spray nitro over poly. However, if the poly is very well cured, and the first nitro coats are light, and allowed to cure between coats, yes, it can be done without lifting the poly. Test...

jcalkin
12-20-2014, 07:50 AM
Beau-Three coats of wipe on/off poly are so thin that sanding back to the wood should not be a problem. I've had no luck spraying lacquer touch-ups on poly. It leaves a halo, and if you try to buff it away the lacquer begins to peel up at the edges. As Chris H. states, an over-all coat of lacquer on thick poly might work if the first coats are sprayed on dry and thin, but its not a job I'd take on at this point. Also, any wax or polish build-up is bound to spoil the job.

I quickly sanded back two of my Min-Wax poly ukes to put on a gloss of Tru-Oil. No problems there.

ksquine
12-21-2014, 06:51 AM
I like Minwax too. Like they said above...wipe on finishes are all about surface prep

dustartist
12-21-2014, 09:25 PM
Be aware there are two types of Minwax Wipe-On Poly. I have used the oil-based version on various things, but not on an instrument. There is a water-based version here in California, and the oil-based version is not available here anymore. I don't use the water-based version, so I don't really know how it performs, but I would guess it's different from what I have used before.

rudy
12-22-2014, 04:20 AM
Be aware there are two types of Minwax Wipe-On Poly. I have used the oil-based version on various things, but not on an instrument. There is a water-based version here in California, and the oil-based version is not available here anymore. I don't use the water-based version, so I don't really know how it performs, but I would guess it's different from what I have used before.

Min-wax water-based wipe-ons that I've seen are labeled as "oil modified" and aren't labeled as "Wipe-On Polyurethane". As such I would think it would be pretty easy to tell them apart. The Min-wax water-based stuff I've used occasionally for furniture would be horrid for use on a musical instrument, so your caution should be well-heeded.

davidrboy
12-22-2014, 07:02 AM
Thanks all for the tips.
I used Minwax satin oil based wipe on poly. But first I did some very careful prep work with 220, 320, 400, 600, 1000. Then I did four coats, roughly twelve hours apart. I did a light once-over between coats with 0000 steel wool, and a very light once over after the 4th coat, followed by a vigourous buffing with a cotton kitchen towel. The finish really looks good and, for a first uke, I am very happy with it.
Koa, Cedar, Rosewood, for the record. Rosette and dots are beach sand from the north shore of St. John, U.S.V.I., my old home.
Already thinking about #2.

sequoia
12-22-2014, 07:23 AM
Already thinking about #2.

If that is your first uke, really looking forward to see what #2 looks like. Nice, comfortable looking instrument.

Oh and also. Could you tell us about your sand inlay. There isn't much good information out there and I've always wanted to try it. Get specific please if you could. Thanks

davidrboy
12-22-2014, 09:54 AM
If that is your first uke, really looking forward to see what #2 looks like. Nice, comfortable looking instrument.

Oh and also. Could you tell us about your sand inlay. There isn't much good information out there and I've always wanted to try it. Get specific please if you could. Thanks

Try this thread: http://forum.ukuleleunderground.com/showthread.php?102376-Sand-Inlays

Kayak Jim
12-22-2014, 10:04 AM
I'm no luthier but any wipe on poly finishes I've used on furniture, etc. is just regular polyurethane diluted with more solvent. In the case of "oil" based, solvent is mineral spirits. Say 35-45% MS, balance polyurethane works well for me.