Removing Rosin from the Finish

[Jeff Bollbach]

Mark-
I just went out in the shop and did as scientific an experiment as I could-here are the results. I tested the following solvents-Toluol, xylene, Turpentine, alcohol. The first part of the experiment was simple dissolution. I took two different rosins-Nyman-hart, Pops and flaked them into jars of the solvent. After five minutes I got these results: Toluol- 100% dissolution, xylene- approx. 60% dis., turp 0% dis, alcohol approx 30% dis.-this was for the nyman-hart, the Pops seemed to dissolve slightly faster.

I then applied the solvents to two basses- one, a Jaeger that I just finished revarnishing yesterday in spirit and the other, my latest bass[the one in the avatar] which was finished in oil a few months ago. Toluol had no effect on the oil and a barely perceptable effect on the spirit- the same as if I rubbed it with a dry cloth[I'm thinking this is because it is barely 24hrs. old-I have a bass coming in tomorrow that I revarnished 3 yrs ago with the same spirit varnish, I'll do the same on it tomorrow to clear up that question]. I got the same results with xylene. Turp had a barely perceptable result on the oil and no effect on the spirit. Alcohol- no effect on the oil and I didn't have to try it on the spirit-stay away from that.

Mark, there are many variations on a theme when it comes to varnish. Basically the solvent is always gonna be turp or spirit but there are many different recipes that may affect how the finished varnish reacts to a particular solvent. As someone who does this full-time and claims to be fluent in all manners of bass repair I have to have thehands, eyes, sensitivity to deal with the subtleties of how these things go. That includes the inevitable mistakes that anyone can make- I have to know how to fix them. Looking back on this thread, I realize that in my desire to hang and have fun with you guys I may have been a bit cavalier in my recommendations of techniques that may be better left to those with a shingle outside their door. I've really been enjoying TB[although my wife is kinda pissed at how much time I'm spending in front of the computer] and I would hate to steer someone into a problem. So I feel the need to state that using solvents on a finish is a "proceed at your own risk" situation. I still stand on my statement that commercial cleaners and polishes will contaminate any openings with detriment to the bass.

[Jeff Bollbach]

Don-
Doesn't this begin to approach a chat room with really long winded users?
I am not trying to be against anyone's products here, I just want people to understand that their bass is a big breathing thing and with the possible exception of a brand new bass there are tons of places that oils can get into the body proper. The aforementioned cleaner contains many ingredients [such as oils] other than its active one[which is xylene if I remember correctly]. A finished varnish has a flat surface that has its own lustre and should never need the addition of a polish. Spooge can be dealt with without the use of solvent. Micro-abrasion to the varnish will dissappear temporarily with the use of polish but IMHO the cons greatly out weigh the pros here- I have spent countless hours cleaning out oil infested cracks-completely unnecessary. This varnish imperfection is best dealt with by french polishing.[which when done properly does not ADD anything to the varnish-that is the greatest sin when it comes to a fine varnish]. Rosin, well apparently that's more of a can of worms than I originally thought. Either prevent it or you may need a trip to your favorite luthier.

.

[oldsaw]

Update #2

Today I was able to find Toluol (toluene) and it does work.
My question to Jeff; it seems to remove a surface layer of something, meaning the shiny layer. I am not removing very much color so I don't think that I am disturbing subsequent layers of finish. Am I doing more harm than good trying to take off the rosin nibs? Based on your knowledge of the bass, should I french polish the surface after I clean it? And if so what should I use? Just a couple of questions for the "expert". I hope that you don't feel that I/we are taking advantage of your expertise. Thanks for you help.
Mark

[Jeff Bollbach]

I could just not come here if I felt I was being taken advantage of[that's assuming I wasn't totally addicted]. No, really I'm having plenty of fun and my typing skills are increasing dramatically. [is there a spellcheck here?]
The loss of shine is illusory. Let's assume you had a shiny marble floor that DB'ers with muddy boots had soiled. You go to mop it and the shine appears to be gone. But it is'nt really- you are just seeing the dried diluted muddy water. You would need to mop it more than once to completely clean it. In this case its diluted rosin. Usually what I do in that situation is French polish the bass. Now that I know what bass you are talking about I can tell you something about the varnish. It is oil varnish and the toluol will not affect it at all. I can say that for sure. However there is another factor.That maker used a technique of inducing artificial antiquing that you need to consider. Basically the technique employed putting layers of inert organics like black walnut dye or just plain dirt inbetween the layers of oil. A layer of varnish is really quite thin. Normal wear and tear does wear away the varnish to varying degrees. The danger in this particular case is that excessive rubbing could cause some loss of color. Proceed with caution. BTW I continued my experiment today-that bass with the tree year old spirit varnish came in and I tried both toluol and xylene on it. With vigorous rubbing no change to the varnish was noted. There was also no loss of shine[he don't do arco].
ps-mark I will get back to you on that other matter.
Also-do you know how to french polish?

[oldsaw]

Jeff,
I've built fine furniture for twenty five years as a hobby and have taken high $ comissions for top end clients, but that's just a hobby.
Mark

[Chris Fitzgerald]

Jeff (or whoever knows the answer),

When applying "elbow grease", what sort of cloth should be used, and in what direction should said "grease" be applied? With the grain? Circular motion? Connect the spooge dots? It's not a big deal, but I have a fairly new bass which is pretty shiny in some places and dull in others because of residual FUM. I wouldn't mind if the whole finish was a bit "flatter" but this half-and-half thing looks a little funny. Like I said, no big deal, but as long as you're here and offering advice, what's the best way to do this? And should the cloth be damp or dry?


Thanks,

FSPOOGETAPE

[Jeff Bollbach]

A dry soft old t-shirt would be the tool I would choose for light duty FUM. A circular motion-just because it is more ergonomic[wax-on wax-off]. Go with warm and damp for any more serious accumulations followed by dry.
I have2 questions for you Chris. First, it may seem silly but is there a way to do spellcheck on these postings? I like to mispell my words on porpoise. And.. the signature statement that many of you employ at the bottom of your posts-how it that done? Surely you don't type it in every time.

[Chris Fitzgerald]

CLEF RORSCHACH,

Thanks for the tip, I'll try that today - I have 5 hours of free time to practice, and I take breaks on TB, so I'll report back soon. Man, I love Tuesdays!

There used to be a spellchecker built in, but it crashed a lot and I haven't seen it since the last upgrade. I usually just keep an old fashioned dictionary within arms reach, but then I like to do things the old fashioned way....plus, you can learn a lotta cool new words that way.

About the signature, go to the red "My Talkbass" button at the top of the forum frame, and then hit "Edit Profile". Once you get in there, you can tell us all about yourself (for anyone who cares to check) and program your signature anyway you wish, including links to soundclips if you want. If you need more help than that, the man to talk to is Xavier G - he's a Slab Off Topic moderator, and when it comes to anything having to do with computers, he is absolutely THE MAN. Hell of a nice guy, too....just don't troll in his backyard, or he'll give you the OH, CANADA smackdown.

Good luck. I found the whole profile thing confusing for a while when I first joined.

(sorry if the Fuquazation wasn't too hot, but I was afraid that you wouldn't feel like you belonged until somebody f****d with your name )

[Jeff Bollbach]

Clef is honored.