French polishing - Shellac?

That’s what I’m trying to work out. There must be some sweet spot between the poetry (and sheer bloody-mindedness) of this:

http://mckeanviolins.com/the-varnish/

and the simplicity (crudeness?) of just thinning a pot of Ronseal and wiping on multiple coats:

https://www.liutaiomottola.com/PrevPubs/WipingVarnish/WipingVarnish.htm

I’m still researching, but I definitely like the idea of a finish which ages. It won’t be just French polish though. Have you seen what a cup of tea does to French polish?

It appears that there is a debate eternal in the violin world over oil vs spirit varnish. It always reaches the ‘what would Stradivarius do’ stage.

Essentially, spirit varnishes are quick to apply and bright in tone. Oil varnishes are slower to apply (up to a week between each coat), soak in deeper and are more mellow in tone. But of course, it all depends etc...

Given the construction of a 5 ply laminated archtop, suddenly a pot of Ronseal doesn’t seem so inappropriate.

Can’t get the 'edit' button to work, so I’ll just stick this in a separate post - oil vs spirit vs Stradivarius:

https://www.violinist.com/discussion/archive/14324/

@jamesbisset

Oil varnishes are fairly easy to apply and the colour stage can even be rubbed in by hand without a brush. There are base, colour and finish stages which can be accelerated by uv light in a cabinet. Lots of utube stuff on this.

Spirit varnish can be a nightmare as it dries on the brush and is hard to apply. It can't generally be used from the bottle and needs to be thinned. I've made lots of mistakes trying.

I like to use a spirit base then oil colour and finish so that if the colour goes patchy it can be wiped off with turpentine and doesn't affect the base.

@rocknroller912 Thanks for that. Would I be right in thinking it’s a fairly expensive way to finish a guitar though? Would you do it?

Touchstone Tonewoods varnishing set for oil varnish

@jamesbisset

I think oil varnish would work on a guitar but your correct it's not cheap. I've just purchased some from Italy and 3 x 100 ml bottles were about £30 each, however that would do 3 violins.

I'm not sure about the guitar neck as violin necks are not usually varnished, so big question there. I think some classical makers use spirit varnish.

I've got a friend who is a chemist and he sent me a utube link this morning on making spirit & oil varnish. Spirit is easy if you can get the ingredients, just put in a plastic tub and shake. Oil making is not for the faint hearted have a fire extinguisher ready, although it's not a hard process just boil Amber till it reduces to 30% and changes colour. Then warm boiled linseed oil and mix. Heat again until the mixture goes translucent. Some people add turpentine and oils like lavender to aid brushing but there is no absolute right and wrong.

@rocknroller912 This takes building a guitar on the kitchen table to a whole new level!

@jamesbisset

Water based finish might be the best thing if you are working in your house. I think Tonetech sell it