Poly (ester) or (urethane)?

[J.D.B.]

When using the term "poly" are y'all referring to poly (ester) or (urethane). I've been digging around here quite awhile with no clear answer. I'm trying to figure out what the "satin poly" is that is on my NOS '87 MM neck. Also, if I spray/wipe poly (urethane) on the fretboard(maple), will I be able to clean it off the frets the same way as lacquer? Thanks,
Josh

 

[62bass]

When using the term "poly" are y'all referring to poly (ester) or (urethane). I've been digging around here quite awhile with no clear answer. I'm trying to figure out what the "satin poly" is that is on my NOS '87 MM neck. Also, if I spray/wipe poly (urethane) on the fretboard(maple), will I be able to clean it off the frets the same way as lacquer? Thanks,
Josh

When guys refer to poly they could be referring to polyester or polyurethane, and truth be told, most of them don't know the difference anyhow. The "satin poly" on your 87MM would be the catalyzed polyurethane that most production basses are finished with these days. It has to be sprayed on and you add a catalyst (to start the hardening process) to it before spraying. Because of this it's not something you can easily do at home. It's a very tough finish almost impervious to chemicals (and chemical strippers). The spray on and wipe on or brush on polyurethanes you buy from paint stores and home centres for use at home are quite different. They are meant to apply easily and to harden without catalysts being added, they contain far less urethane and are not all that impervious to chemicals. You can strip them with a good chemical stripper. They also don't harden nearly as tough as the factory finishes. Polyester is also a tough finish and not something easy to use at home. It's often used as a sealer under other factory finishes. It's impervious to most strippers also. Anyhow, all these factory finishes are special purpose products designed to be applied by experienced pros and not easily available or suitable for the home hobbyist.

If you spray or wipe on poly you get from a consumer outlet on your fingerboard you can remove it from your frets while it is still wet with a cloth wetted with mineral spirits, also known as paint thinner. You'll also use that to clean your brushes. Varsol is one well known brand of mineral spirits. Once it dries though, you'd have to sand it off or steel wool it off or use a chemical stripper. You wouldn't want to do that. Lacquer thinner would also remove it with a bit of work. But it would also probably get spilled onto the fingerboard and mar the finish you've put on that.

I don't know why you would want to put polyurethane or any surface film on the fingerboard of your bass. Maybe to waterproof it? Probably it won't hurt. I sometimes use boiled linseed oil for that purpose. Some guys use tung oil. These finishes soak into the surface and are wiped off so they don't form a film on the surface. Other guys use lemon oil or some othjer furniture oil which doesn't cure the way linseed and tung do, but makes the wood look better and offer a slight amount of moisture protection.

But actually, you don't need to do much to your fingerboard except keep it clean and maybe moisten it a bit once a year with lemon oil or some other form of mineral oil.

 

[J.D.B.]

Thanks, that explains alot. As far as finishing over the fretboard, it's a one-piece maple neck and the board is already coated with the poly like the rest of the neck. Rather than tape it off, I was thinking of the lazy way out and continuing to cover the whole neck. I just want to remove it from the frets when it's done. One other question, MUST I use poly on the neck or can acrylic lacquer be used, that is, will it stick to the poly?
Josh

 

[62bass]

Thanks, that explains alot. As far as finishing over the fretboard, it's a one-piece maple neck and the board is already coated with the poly like the rest of the neck. Rather than tape it off, I was thinking of the lazy way out and continuing to cover the whole neck. I just want to remove it from the frets when it's done. One other question, MUST I use poly on the neck or can acrylic lacquer be used, that is, will it stick to the poly?
Josh

To really get anything to stick to the poly well, including new poly, the old surface should be roughed up some with fine steel wool and thoroughly cleaned. I'd steel wool it first, then wash it with a bit of dish soap and water, rinse off the soap residue with clean water and a cloth and let it dry before applying the new finish.

I wouldn't put acrylic over polyurethane. Better to stick to polyurethane. I'd consider using the Minwax wipe on poly myself. You apply it with a cloth and it dries really quickly. It's thinned out for wipe on application and is a bit easier to clean up after. I don't know if I'd mask off the frets. I'd apply the poly with a cloth and as I go along from fret to fret wipe off anything that gets on the top of the frets right away with a dry cloth followed immediately by a cloth dampened in paint thinner. Any finish that sticks to the sides of the frets will be minimal and will not affect playability. You can brush full strength poly with a small brush but it can drip and run and clean up is harder. Make sure you clean up poly from the tops of the frets and anywhere else you don't want it before it starts to set up. Once it dries you'd have to sand it off or use a chemical stripper and you don't want to get into all that. That's pretty much the same method I use when applying boiled linseed oil to bare rosewood fingerboards.

If you can't remove the neck from the body before you do this, thoroughly tape off the pickups with masking tape before steel wooling as the steel wool residue sticks to the magnets and is impossible to remove. Clean up all steel wool residue before removing the tape.

 

[SGT. Pepper]

If you already have a finish on the board why do you want to go thru all that aggrevation?
If you must and you choose a non-commercial coating, try Man-O-War Spar Varnish.

 

[Pilgrim]

Acrylic lacquer is much too fragile and prone to abrasion and chipping to hold up on a maple fretboard. You would wear it off in short order.

 

[J.D.B.]

If you already have a finish on the board why do you want to go thru all that aggrevation?
If you must and you choose a non-commercial coating, try Man-O-War Spar Varnish.

Sorry about that. I failed to mention that the finish on much of the neck is thin and not covering everything. Like it was applied at warp 3. I just want it covered before installing it. It survived this long on the shelf, so I don't want to mess it up now. Thanks for the responses so far!
Josh