Hempseed oil for varnish

[Randall The Restorer]

* Please no drug-use humour *

Have any of used or made instrument varnish containing Hemp( Cannabis) Seed Oil? If yes, how did it work on a VSO or guitar? There are hempseed oil-based commercial varnish products made for wooden boats and outdoor wood decks, etc.

Be considerate of all readers, present and future, and confine your comments to violin making.

Thanks in advance.

Sincerely,

Randy O’Malley 

 

[joerobson]

On 8/10/2024 at 2:34 PM, Randall The Restorer said:

* Please no drug-use humour *

Have any of used or made instrument varnish containing Hemp( Cannabis) Seed Oil? If yes, how did it work on a VSO or guitar? There are hempseed oil-based commercial varnish products made for wooden boats and outdoor wood decks, etc.

Be considerate of all readers, present and future, and confine your comments to violin making.

Thanks in advance.

Sincerely,

Randy O’Malley 

 

I have expermented...film failure is the problem even if you can get it to cure.

I have a bottle if anyone wants it.

on we go,

Joe

[LCF]

Hemp oil has high levels of beta-sitosterol and gamma tocopherol which are powerful antoxidants, problematic for a varnish.

 

 

[MikeC]

The wikipedia article says it's a drying oil.   

[Spelman]

I've played a few fiddles with hemp oil, definitely helps the highs

[JacksonMaberry]

7 hours ago, MikeC said:

The wikipedia article says it's a drying oil.   

It's classed by Livache/McIntosh and in Mattielo's volumes as a semi-drying oil, and there is discussion on how to modify it to improve its drying properties. My own tests with some supplied by a very good US maker, who uses it in varnish he makes for his own instruments, was that it was good but not in my view great. 

Linseed oil is the gold standard, certainly, and not expensive. Walnut oil is another top candidate. 

Perilla oil, by the numbers and in my tests, is about the best drying oil for varnish short of Tung. It is, however, very expensive and variable in quality on the bulk market, with the larger part of it coming from China (same with tung) and some shipments being adulterated. 

One major advantage of sticking to linseed oil, however (which I do myself in my commercial varnishes) is that it behaves as we would expect it to. 

Note that all drying oils benefit from some manner of processing from their raw state before being used in varnish. Doing this improves both curing time and toughness. Because of this, some opt not to process their oils, using them in their raw, filtered state (typically cold pressed), because they prefer a chemically and physically weaker varnish, which is easier to antique.