Violin Forum/Message Board

actonern · Super Member Joined: 15 Aug 2007 Posts: 444

No matter what mixtures of short oil varnishes I use on the last clear coats of varnish (including actual fused amber formulations) the varnish remains quite soft for well over a year. By "soft" I mean that surgical tubing on a shoulder rest will leave an impression, even if it slowly dissapears after some time.

I've tried a final overcoat of really thin shellac over oil in experiments, and the result is much tougher, but more prone to crazing.

Any others with thoughts on this?

Best regards,

Oded Kishony · Posted: Fri Jul 11, 2008 2:03 pm Post subject:

You don't say enough about your varnish to come to any conclusions. How long do you cook it, do you treat the resins in any way? What kind of oil you use, what do you thin it with, what is the actual resin to oil ratio? What is the ground / sealer preperation? Why kind of drying protocols/ drying box you use? All these factors have a bearing on drying.

Oded Kishony

Geemac · Posted: Sat Jul 12, 2008 8:47 am Post subject: Drying oil varnish

You may want to add some Japan Drier to your oil varnish mix. Test it first on something that is not your violin. I make my own oil varnish and it takes just over a week to become somewhat dry to the touch. Japan Drier is available at most good paint stores. I found mine at Windsor Plywood.
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Dave Chandler · Posted: Sun Jul 13, 2008 12:41 pm Post subject: Drying time

Geemac,
A week to be dry to touch sounds like a heck of a long time. I lay mine out in the sunshine and within hours its dry to the touch. Just gotta watch the weather. An alternative you'll find in earlier posts, is use of black light to get sufficient uv to speed up the varnish curing. I do have a little Japan Dryer in my varnish solution, perhaps 2 or 3 %, and I also thin it with turpentine and apply ever so thin coatings.
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Jack H. · Posted: Mon Jul 14, 2008 11:26 am Post subject:

Actonern,
What kind of oil are you using?
Linseed?
Is it cold pressed?
what are your ratios?

Geemac · Posted: Mon Jul 14, 2008 12:32 pm Post subject: Drying oil varnish

Two parts raw linseed and one part turpentine.
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Geemac · Posted: Mon Jul 14, 2008 12:35 pm Post subject: Drying oil varnish

It might be because I am glopping it on with my hand. I see a mention of 'ever so thin' coats. I'll try that next. No matter what, I am enjoying what I am doing.
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Jack H. · Posted: Mon Jul 14, 2008 12:57 pm Post subject: Re: Drying oil varnish

Geemac · Posted: Mon Jul 14, 2008 2:35 pm Post subject: Drying oil varnish

I took some sticky buildup from my spruce tree and melted it, on my stove, in a steel dish. Then I filtered it and added it to the varnish. (I'm an experimenter at heart)
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actonern · Super Member Joined: 15 Aug 2007 Posts: 444

Hi all...

The varnish approach is the same as Manfio's, well described on a number of threads. The "Marciana" formula is 1 part walnut oil well boiled for a few hours, mixed with equal parts of mastic and colophony also well cooked and weighed up after cooking to make up a final one to one ratio of resin to oil.)

This varnish is used for sealer and mixed with pigments for color coats.

For final clear I mix this same formula with about 1/2 of the dark amber varnish available from "Alchemist."

It dries to the touch in about 4 hours, but even left to harden up for 2 days between coats and then a week before set-up it prone to receive impressions for a good time thereafter. By "impressions" I don't want to convey that it's soft like road tar. Rather that if warmed by the sun, one could press hard with a finger and leave a slight print on the varnish, which will slowly dissapear if buffed with the hand or left alone for a while.

Perhaps that kind of flexibility is an accoustically beneficial characteristic of oil varnishes? I've read elsewhere that the old Cremonese varnishes were scoured back to their present day look relatively early in their lives. Is it the shellac overcoats they've received thereafter that has toughened up an originally soft skin?

MANFIO · Posted: Wed Jul 16, 2008 7:50 am Post subject:

Hi actonern! The Marciana recipe is 2 parts of oil to one part colophony and one part mastic.
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actonern · Super Member Joined: 15 Aug 2007 Posts: 444

Hi Manfio:

I think we're talking about the same thing... the end result is equal parts of oil and resin (albeit the resin part is comprised of two equal parts of colophony and mastic.)

Make sense?

MANFIO · Posted: Wed Jul 16, 2008 11:02 am Post subject:

Oh, yes... this varnish works quite good in a paste with fine pumice to make a good ground, I use it on my instruments under the advise of Neil Ertz, from England.
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Geemac · Posted: Thu Jul 24, 2008 8:47 am Post subject: Drying oil varnish

I have stripped the violin a restarted. I applied a very thin coat of varnish and it is drying quite nicely. Thank you for the help.
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