1704 varnish

[notenoughtime]

I've made a 1704 recipe varnish with 180 grams Seedlac, 30grams sandarac, 30 grams Elemi, 15ml spike lavender oil and denatured alcohol. I heated it in a water bath and strained it. It goes on well and dried quickly but it is quite orange in color. Looks nice on the wood but the binding turns orange and is obviously not desirable. Could anyone tell me how to proceed? Not sure if my recipe is off or I need to clean the binding up better or apply more carefully so as not to goop up the binding. Any advise would be much appreciated.

[Stephen Perry]

Seedlac is orange. For clear varnish, pick the clearest things you can. It's entirely possible to take Zinser dewaxed and simply mix in some dissolved sandarac etc. I use a different formulation I like better, but it's going to wear away on a mandolin fairly quickly. I like that look, but it's not typical for mandolins.

Scraping the binding seems a regular part of some builders' schedules. A bit tedious.

Regardless, you likely made it correctly, just the nature of the finish.

[peter.coombe]

It really depends on the seedlac. Some has a strong colour, some has a light straw colour and is almost clear when you apply it. Get the light seedlac.

[treidm]

It really depends on the seedlac. Some has a strong colour, some has a light straw colour and is almost clear when you apply it. Get the light seedlac.

I wonder, is that determined by what the bugs had eaten? or something else....

[peter.coombe]

I wonder, is that determined by what the bugs had eaten? or something else....

Yep, I think it does depend on what the bugs eat. Seedlac is the raw form of shellac. The pale stuff I had was difficult to dissolve and I had to heat it, but the end result was quite a nice varnish.

[Stephen Perry]

Same with the other resins - picking the lightest color gets the lighest varnish. Some really yellows with time. I like that, but it's not for everyone.

1704 is far from the only solution varnish. Lots of recipes. Different drying rates, brushing characteristics, wear characteristics. I know one fellow used acetone instead of alcohol and sprayed (with full protection). I make at least three kinds I can think of at the moment.

One can also modify commercial varnishes. Used to be a nice Ace brand oil varnish. I'd dissolve mastic in real turpentine, mix that and some good artists linseed oil with it, make a very nice varnish that would go on beautifully. The mastic and oil would set up over a couple of days well enough, and the final instrument really look great after a few days in the UV cabinet.

[notenoughtime]

Sounds a bit too sophisticated for me at this stage. Since my original post I have sanded and applied a second coat and it is coming around a bit. It's a little darker than I anticipated and compared to photos I have seen on web sites my batch does appear darker, but I wonder if it might now be because i let the heat get away from me at one point. I may try a small batch experiment without heating it.

[notenoughtime]

How would I go about coming up with a formula that substitutes a more blond shellac flake instead of the darker seedlac?

[Stephen Perry]

You can finish with blond shellac alone. A great place to start is with violin varnish recipes. You can just substitute blond for seedlac. You can add stuff to Zinser de-waxed. Solution finishes are easy. Hunt around a bit and you'll find the characteristics of various resins.