oil finish Mixing my own True Guitar Finishing Oil

[Bizman62]

There's all kinds of wipe on oil finishing products that can give a mirror finish when applied a sufficient amount of layers. I've been using Crimson's Guitar Finishing Oil which I've heard is a counter engineered and modified version TruOil or something similar.

So after having read articles and seen videos about how that type of finishing product used to be common knowledge back in the fifties or so, and how people forgot the recipe because of moving to cities and losing the paths to agrarian wisdom I've been toying with the idea of mixing my own so I could change the buildup properties at will. Plus that the price would be a fraction of the commercial products!

The basic recipe is very simple but what held me back was the terminology: The word "poly" was used in all of the recipes and for what I know it translates to "lakka" (<lacquer), both of which cover all sorts of more or less clear finishes. Obviously water based ones were out of the question but with the rest there was still too many question marks for me. Finally yesterday I met a painter who shed some light to the matter.

So, to the recipe: In all simplicity there's Boiled Linseed Oil (BLO), turpentine and poly. The basic mix is one third each but by using more turps it penetrates better and with more poly it builds up faster. Simple as that! Obviously the main issue with poly is not to use water based ones. I'd also rather use something that can be diluted with mineral spirits/White Spirit as pine turpentine can be substituted for that . Basically you could use mineral spirits instead but somewhere I read that there's a higher risk of combustion with that.

I searched through my storages and found a can of solvent based clear Urethane Alkyd - but where's the "poly"??? Well, it's actually Polyurethane but they often seem to drop the Poly off. Oh well... The product can be diluted with mineral spirits and as it also seems to contain pine oil I felt safe to mix some pine turpentine into it. Plus some BLO -  which in Finnish is called "vernissa" (<varnish)! Anyhow, they all seemed to mix easily, no lumps whatsoever! I'll wait until tomorrow to test it.

 

[Bizman62]

Today I tested it on some scrap wood and boy did I like the result! It dries in a quarter of an hour, is almost colourless and leaves a nice sheen with just one wipe. Here's a sample on an offcut of an earlier build. The dark stain on the left is from the steelwool+vinegar, in the middle it's just bare wood. Nogal, cherry and merbau with birch stripes to be exact.

[spindlebox]

On 12/2/2022 at 4:04 AM, Bizman62 said:

There's all kinds of wipe on oil finishing products that can give a mirror finish when applied a sufficient amount of layers. I've been using Crimson's Guitar Finishing Oil which I've heard is a counter engineered and modified version TruOil or something similar.

So after having read articles and seen videos about how that type of finishing product used to be common knowledge back in the fifties or so, and how people forgot the recipe because of moving to cities and losing the paths to agrarian wisdom I've been toying with the idea of mixing my own so I could change the buildup properties at will. Plus that the price would be a fraction of the commercial products!

The basic recipe is very simple but what held me back was the terminology: The word "poly" was used in all of the recipes and for what I know it translates to "lakka" (<lacquer), both of which cover all sorts of more or less clear finishes. Obviously water based ones were out of the question but with the rest there was still too many question marks for me. Finally yesterday I met a painter who shed some light to the matter.

So, to the recipe: In all simplicity there's Boiled Linseed Oil (BLO), turpentine and poly. The basic mix is one third each but by using more turps it penetrates better and with more poly it builds up faster. Simple as that! Obviously the main issue with poly is not to use water based ones. I'd also rather use something that can be diluted with mineral spirits/White Spirit as pine turpentine can be substituted for that . Basically you could use mineral spirits instead but somewhere I read that there's a higher risk of combustion with that.

I searched through my storages and found a can of solvent based clear Urethane Alkyd - but where's the "poly"??? Well, it's actually Polyurethane but they often seem to drop the Poly off. Oh well... The product can be diluted with mineral spirits and as it also seems to contain pine oil I felt safe to mix some pine turpentine into it. Plus some BLO -  which in Finnish is called "vernissa" (<varnish)! Anyhow, they all seemed to mix easily, no lumps whatsoever! I'll wait until tomorrow to test it.

 

still not really sure what the recipe is.  What is POLY?

1/3 Turpentine
1/3 Boiled Linseed Oil
1/3 _____________________ (name of a product available at True Value?)

not sure if poly is laquer or gloss/satin Polyurethane?

Sorry, there's just lots of explanation above.

[henrim]

52 minutes ago, spindlebox said:

What is POLY?

Poly is a widely used misnomer in guitar finishing. I guess it usually means some kind of polyurethane based varnish. But can as well be for example polyester or even poly acrylic. You never know.

Although in this case, judging from the can in the photo, it is a urethane/alkyd based varnish.

[Bizman62]

10 hours ago, spindlebox said:

still not really sure what the recipe is.  What is POLY?

Funny thing is that I struggled with the very same question. The recipe comes from your side of the pond and each and everyone talked about POLY!

As @henrim said the stuff I used is a polyurethane/alkyd based varnish. Never heard about True Value before, but Google tells it's a hardware store over there. From their site I might recommend the Old Masters oil based polyurethane - logically thinking if you mix oil based with oil you can't go wrong!  But for what I've read, any poly van be used as long as it's not water based. There's MinWax, Varathane, Zar, Enrich, ProLuxe... If they suggest washing the brushes with turpentine/mineral spirits, the product most likely will do.

The purpose of "poly" is to add substance to the oil so it builds faster. An old violin makers' recipe mixes fir resin with linseed oil and turps - there's videos how to cook that mix but it's quite dangerous as you're dealing with high temperatures and flammable materials.

As I already said in my previous post it's quite confusing with the names of finishing products. In English I know there's lacquer, varnish, poly, finish or just clearcoat, at least by the labels of the cans. Then there's subcategories like nitro(cellulose) and 2k. So far so good, however in the Finnish language we have words like "vernissa" which sounds like "varnish" but means BLO! And studying "lacquer" revealed that the word originates from the lac bug of which "shellac" has been made for thousands of years.

[henrim]

The use of terms varnish and lacquer can be confusing. At least for Finns, because our words vernissa and lakka look like direct translations from the English words, but they actually have a different meaning. The closest translation to varnish would be lakka, which can mean a wide variety of different types of clear coatings. Vernissa on the other hand is a certain type of linseed oil based finish (and I believe that used to be the case in English too back in the day when there weren’t any other types). But unlike Finnish word lakka, the English word lacquer refers just to a solvent based finish, like nitrocellulose lacquer. In guitar finishing context lacquer usually means nitro, but there are other lacquers too. Off course it doesn’t help that these words get mixed use in both languages.

[Bizman62]

4 hours ago, henrim said:

Vernissa on the other hand is a certain type of linseed oil based finish

Actually some cans of "Vernissa" also say "Keitetty pellavaöljy", i.e. "Varnish" being the same as Boiled Linseed Oil. Some sources tell that it isn't actually boiled, some say that raw linseed oil is boiled with some metal salts to make it harder and faster drying. Whom to believe? Anyhow, BLO is a mix of various ingredients whilst raw linseed oil can be used for salad dressings.

By the way, BLO can be replaced with Tung oil which is pressed from the seeds of a Far-Eastern tree. Both are drying oils that build a shiny surface when applied several times, a soft natural lacquer if you will. Tung oil makes a little harder finish.

[henrim]

3 hours ago, Bizman62 said:

Whom to believe?

Yes, I know that vernissa has two meanings. I have learned to use it for that hard drying mixture, but I have heard people using for plain boiled linseed oil. Actually it would be nice if it was used just for that. To make a distinction between cold pressed and boiled linseed oil.