Polishing compound (redux)

[speralta]

Greetings,

 

I have followed these boards for a few months, having been researching the process of varnishing violins.  I am working on my first violin varnishing project using a slight variation of the method Henry Strobel recommends here.  The variant is that I have used Tetley tea instead of salmon colored dilute with the walnut oil, iron oxide and colophony recipe.

 

This method involved tea, 2 layers of varnish with no Uberzugslack (clear overcoat) followed by a rubbing compound.  

 

On such a finish, is it still appropriate to use the commercial automotive polishing compounds like t241a, No. 7 and Novus Plastic Polish number 2 (are these all diatomaceous earth?)  

 

Or would it be better to try pumice or rotten stone in some polishing oil?  If so, what oil?  Walnut? Olive? Linseed?

 

Can diatomaceous earth be substituted for pumice or rottenstone?  It seems finer than pumice.  I have never used rottenstone.

 

Any suggestions and/or warnings to the newly initiated would be appreciated.

 

[Michael_Molnar]

I am familiar with rottenstone or pumice and olive oil. This is a non-dying oil that is easy to clean up. The purpose of the oil is to avoid evaporation that you get with water. As for the other polishing compounds, YOU have to test them on some sample test strips and see if YOU like the results. Pumice comes in different grades. I think pumice (4F) is more aggressive than rottenstone. Someone should verify whether I am right. 

[DarylG]

Any suggestions and/or warnings to the newly initiated would be appreciated.

 

Be sure the varnish is well dried before attempting to polish with abrasives. I wait at least a week with the varnish I'm using.

 

 Pumice comes in different grades. I think pumice (4F) is more aggressive than rottenstone. Someone should verify whether I am right. 

 

Much more aggressive, and too aggressive for use on violins IMO.

[DGV]

 

Be sure the varnish is well dried before attempting to polish with abrasives. I wait at least a week with the varnish I'm using.

 

Indeed.  Polishing prematurely can ruin a good varnishing job.

[James M. Jones]

I get concerned about using a non drying oil as a lubricant , I have been using water , sure it dries out , but I just add more , It seems to cut faster ...a lot faster . and only needs a dusting off when dried , moreover the polishing compound ,,,dental pumice , (thanks Mike) when the water dries off a white residue is left, as a sort of tell , with oil as a lubricant the pumice never whitens and it's hard to tell exactly when it is all gone.

[DonLeister]

I agree with Michael, you have to test the compounds and see if they are something you like. 

 

Personally I stay away from any automotive polishes not knowing what is in them, like silicones-bad. 

 

Tripoli works well for me, the stuff from International Violin Co. It is very fine and will cut fast if you use a thin oil or mineral spirits mixed with the oil, or water  with or without a drop or two of dish soap. The thicker the oil is the slower it cuts. 

 

Any results you have will depend on what your particular varnish ends up being on the finished instrument. I'm sure no one here has the exact same varnish as you do. If it is a real tough varnish it can take a lot of effort to get out scratches from courser grit abrasives like pumice so I would proceed with some caution.

 

I hope your project turns out well for you!

[FredN]

I'd try J Jones (post 5), using water for any oil that cannot totally be removed can create major trouble, I can attest to that. All the inst's I varnished was with fossil copal varnish, a hard resin, so I don't know how this would apply to your situation. When I felt I could slide my fingers around with little pressure and no stick, I would use fine pumice in some water, fold 1200 sandpaper so it is a slightly stiff ca 2" square, or a soft wood block, and gently rub to remove only particles sticking up from the surface. The dried white powder left after drying is easily removed with wiping and brushing. I do this just about every coat, this varnish required at least 3-4 coats.

[Arthur65]

Greetings,

 

I have followed these boards for a few months, having been researching the process of varnishing violins.  I am working on my first violin varnishing project using a slight variation of the method Henry Strobel recommends here.  The variant is that I have used Tetley tea instead of salmon colored dilute with the walnut oil, iron oxide and colophony recipe.

 

This method involved tea, 2 layers of varnish with no Uberzugslack (clear overcoat) followed by a rubbing compound.  

 

On such a finish, is it still appropriate to use the commercial automotive polishing compounds like t241a, No. 7 and Novus Plastic Polish number 2 (are these all diatomaceous earth?)  

 

Or would it be better to try pumice or rotten stone in some polishing oil?  If so, what oil?  Walnut? Olive? Linseed?

 

Can diatomaceous earth be substituted for pumice or rottenstone?  It seems finer than pumice.  I have never used rottenstone.

 

Any suggestions and/or warnings to the newly initiated would be appreciated.

The tea, are you using it as a ground as the first step on a white violin or as a colorant over a ground layer ?

Has anyone used tea as a ground, and how effective is it ?

[speralta]

The tea, are you using it as a ground as the first step on a white violin or as a colorant over a ground layer ?

Has anyone used tea as a ground, and how effective is it ?

For this first violin, I just followed Strobel's method.  No ground other than the tea to stain.  My next experiment will use propolis as the ground without the tea. 

 

DonLeister - You said silicone is bad.  Are silicates bad?   I mention it because some people recommend scouring rush, which contains silicates as a polishing agent. 

 

Regarding auto polishes... folks here might be interested in this old patent application for auto polishes.  There is a lot of information about ingredients for abrasive finishes, even specific formulations that can be made.  

Edited April 27, 2015 by speralta

[yancypup]

Silicone is not the same thing as silicates.  To me, silicone is a lubricant that is almost impossible to remove once it is on something and silicates are small abrasive particles like sand.  This isn't from my violin experience (of where there is almost none) but from other life experiences.