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As I slowly apply finishing oil to a project gun this summer, I continue to have a bit too much time to think about traditional slakum. And I was looking back at some of the posts here while preparing to make a new batch of oil. I didn't follow an exact 'recipe' from anyone (the effort is recorded at the bottom of the linked document), but in the process of reviewing, I was again impressed by the significant time and effort that Damascus, Salopian, and others have put in to helping interested newcomers understand traditional finishing processes.

I decided to summarize some of the things I had read here and elsewhere, including an outline of Damascus' thread on his process. Doing so was very helpful to my understanding of the constituents and application of slakum, so I decided to type up my notes.

I figured I would share that 'digest' for a couple of reasons: 1. to say thank you to the many folks who have freely shared their knowledge, and 2. to hopefully make some of this a little more accessible for newcomers to the subject.

The link below will take you to a google document that I intend to slowly add to and edit. In fact, there are some missing bits of info that I would welcome some help with.

Also, everywhere that there is an underlined bit of text, it is a hyperlink, either to information or a source for purchasing materials. There are multiple sources for most of these things, and not all of the links are necessarily to the cheapest or 'best', although, over time, I hope to use this as a 'catalog' of sorts for the materials I use most.

I intend for this document to improve and grow, so if you have a traditional oil recipe or process that you would like to share, I would be very grateful to see it. As Damascus says, 'its in the way that you use it,' so please include your process if you have one that's worth sharing.

* I would also note that my excluding some finishes that have been shared (e.g. SKB has been very helpful and generous with information regarding his process e.g. here ), is for the simple reason that I wanted to focus on the most traditional methods and materials-- i.e. no polyurethane (alkyd does make an appearance though). Perhaps a 'modern gun stock finishes of DGJ' is in order, but here I only wanted to untangle the gum arabics and asphaltums and madder roots of my mind.


The document will be accessible by anyone with the link. Feel free to share it if you find it helpful.

Traditional Double Gun Finishes

EDITED (The history behind this has also been discussed previously on these forums incl https://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=54629&page=1 )

I happened to be in London the other day and called in at Purdey. During a discussion the gentleman in charge of the gun room we turned to stock finishes and techniques. He pulled out a copy of Lt Col. Peter Hawker's book and flicked to Manton's recipe Salopian once posted in these forums. He went on to recount the story behind the Purdey finish. Apparently a very long time ago they employed a gentleman by the name of (Harry) Lawrence. Over time they noticed that the finish on the stocks he did lasted a lot longer than others. It turned out he was using his own formula. Purdey tried to buy the recipe. However, Lawrence refused. He did, however, agree to sell the bottled finish to Purdey. This continued until his son, on his retirement, agreed finally to sell the formula to Purdey. To this day it remains a closely guarded secret with just a few trusted people knowing the formula which is locked up in a safe. Apparently they make it in batches and various batches develop a reputation within the company for greater or lesser quality. Those in the know at Purdey, when shown the recipe in Hawker's book, responded "no that's not it." Unfortunately, I couldn't recall the recipe Salopian said had been attributed to Purdey to further the conversation although, in any event, the gent I was talking to was not one of the few 'in the know' anyway.

Woodreaux

One other point you might want to edit. I was conversing privately with Ernie aka Damascus about the amount of terebine driers in his slacum formula, remarking that it was a very high drier content. I don't think he'd mind me repeating his response here:

"The amount I gave was correct at the time. Though it is incorrect now. The driers I used was from a gallon I purchased many years previously with its base formulated around Lead rather than the Cobalt and other heavy metals that are now used today in Japan and Terebine driers. In view of this the required amount is minuscule rather than the amount given in my post."

He's been very kind sharing his knowledge and techniques and I'd hate for those that follow to miss this.

Note that a cobalt drier such as the one listed above will push the color of the finishing oil awards green (when you add a deep dark blue to a golden yellow) which can be rather alarming at first.

According to Langridge:

"When initially mixed together, the driers will impart a blue/green cast to the oil or medium with which it is mixed. Exposed to indirect sunlight for a few days will remove this colour difference (Exposing the oil or medium to indirect sunlight will not sun bleach or thicken the material). If used in correct proportions, the colour of the cobalt drier will not interfere with oil paint brightness or colour saturation."

I also add a little red oil to develop a rich brown colour to the finishing oil.

Note, also, "Cobalt Driers are known as ‘surface’ siccatives (driers) and will only speed the drying of the surface of the paint film. They are not ‘through-film’ siccatives and do not perform as successfully with thick films of oil." I'd very much like to try colorless Siccatif de Courtrai https://www.lefrancbourgeois.com/row/product/white-courtrai-siccative/ https://en.pebeo.com/catalogue/siccatif-de-courtrai-75-ml-75-ml-650401 "This zirconium-based siccative acts in depth and on the surface. It accelerates drying and balances thick layers while hardening. It is very powerful and must be controlled with care. Colourless, it does not alter light colours." I can't find this product in the US however.

FWIW I think you will find "rose pink" is made by "precipitating chalk or whitening with decoction of Brazilwood."

https://ia802203.us.archive.org/20/items/rudimentsofcolou00fiel/rudimentsofcolou00fiel.pdf

I've been mostly off of the forum for a while. I appreciate all the input and can see that some edits to the Digest are in order. Thanks to all of you for your interest and information