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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
Last edited by Woodreaux; 06/30/20 09:38 PM.
Jim
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Jim,
Well done.
Thanks, John
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Whoa!! That's a really great resource you are putting together. Thanks for all the effort and time.
_________ BrentD, (Professor - just for Stan) =>/
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Tom C
�There are some who can live without wild things and some who cannot.� Aldo Leopold
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Maybe this can be pinned somewhere that it won't scroll into oblivion.
_________ BrentD, (Professor - just for Stan) =>/
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Brent,
Can Dave do as you suggest, move it to the second forum along with Damascus. Hate to see this get buried.
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Brent,
Can Dave do as you suggest, move it to the second forum along with Damascus. Hate to see this get buried.
He certainly can. The only question is, "Will he?"
_________ BrentD, (Professor - just for Stan) =>/
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Thanks for the feedback.
One thing that I can do to keep it from disappearing is to post when I've updated something substantially. That would work for a little while at least.
In fact, I have already revised most of the section from Diggory Hadoke's info.
(I also fixed (?) the spelling of slakum to be slacum, which appears to be the right spelling. Not sure why I always want it to be a 'k')
Last edited by Woodreaux; 06/30/20 02:03 PM.
Jim
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Jim,
Some one posted way back when in the Spring that Diggorys formula was originally posted or cited in James Howe with modifications with driers. Have you run across them? I inter library loaned his Modern Gunsmith but with the shutdown it never arrived.
John
Last edited by susjwp; 07/01/20 06:19 AM. Reason: Spelling
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I'm looking at it now, and I don't see one that's exactly the same. I'll post them all in a minute. He has 7 linseed oil formulas
Images of the boook posted below.
Edit: I first posted that Diggory's was closest to Howe Formula #5. But I misread the volumes of ingredients. A closer inspection would suggest that Dig's oil is not derived from one of the Howe forumlae.
Last edited by Woodreaux; 07/01/20 02:30 PM.
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Deleted to de-clutter post.
Info available in the document
Last edited by Woodreaux; 07/03/20 06:13 PM.
Jim
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Jim,
Thanks and very impressive. Another set of formulas to add to the digest. And yes, they are not a ditto of Diggorys. I always assumed we coated/soaked with alkanet before finishing but adding it to the final finish sounds interesting.
John
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Thanks John. When I saw how specific Howe is in the formulas and applications, I had the same thought. I'll add them to the digest once I've gotten the info into outline format. I have made some more substantial additions and edits to the 'digest' and will continue to do so as I gain info. It is now up to 16 pages, and includes forumlas and processes from Damascus, Salopian, Dig, and Ken 61. If there are other traditional methods hidden in the forum posts, I would be thankful for someone pointing me in the right direction. Here is the link again, to make it easier to find since we are up to a second page of posts: Traditional Double Gun Finishes
Jim
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Jim,
Again, nicely done. All this information in one place. I am going to order more alkanet and try as per Howe boiling in turpentine and strain.
Thanks, John
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Thanks for a nice resource that you have complied all in one place Jim. I might have to circle back and give slacum a go once again.
Steve
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If you do give it another try, let us know how it goes. Glad to see your greener re-stock project on the pro page. Looking forward to seeing it come together.
As for the slacum digest, it's up to 40 pages now and includes lots of different formulas.
From DGJ- Damascus, Salopian, Dig, Ken61, and Balistix999. From non-DGJ sources- J Howe, D Newell, D Mills, D Westbrook, B Farman, N Kypridemos. Eventually, I'll get around to sorting out the info in Dunlap and Walter Howe's books.
Jim
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I've changed the restrictions to the document so that anyone interested in accessing it will need to have permission. This is mostly for my own curiosity so that I can know who is using it.
If you would like access, please send me a message with your email address, and I will be glad to add you.
Any feedback or suggestions for edits or additions would also be appreciated.
Jim
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Jim, Well done in compiling all this information. When I was heavily involved in stock finishing I found that Naptholene was a wonderful constituent.Much knowledge and information can be gained from the Paint Industry (PPG) after all they provide gloss finishes and air drying products.Although it is a product of our times I dislike poly.
Last edited by salopian; 12/12/20 04:38 AM.
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Thanks! I've got two questions for you: 1. For the naphthalene, did you just dissolve mothballs in your finish? 2. Your Manton recipe included rose pink. I've seen it listed in many old recipes for varnishes / paints, and I've learned that pink is a generic name for a kind of pigment, rose being the color that we associate with 'pink'. nonetheless, I found it extremely difficult to locate online. A couple of interesting links regarding pinks and rose: Rose Madder Pigment Rottenstone Pink
Jim
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Updated with a "digest" of the Purdey process as demonstrated by Purdey finisher James MacDonald.
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James, Naptha purchased from chemical supplies company.Rose Pink is in an old recipe but I never tracked it down .Does dissolved mothballs produce Naptha ? Can I access the Purdey finishing treatise?
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I thought you were referring to Naphthalene, which is a major constituent of mothballs. As opposed to Naphtha, which is standard lighter fluid. I was wondering if maybe the naphthalene gave a certain old-closet kind of smell to the gun! If you look at the Digest, PAGE 37 (Direct Link), I've just reformatted the outline of the purdey process. The full video can be accessed by clicking the underlined link in the title of that section or by clicking here HERE To go to the specific time for a given step, you can look at the time in the screenshot that I included from the instagram video. On that note, every place in the Digest that has underlined text is a hyperlink that will take you to the source of the information, a purchasing source, etc.
Last edited by Woodreaux; 12/13/20 11:33 AM.
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Is there any actual formulas for the purdey slakum? I live in the humid south and my minimal experience with the slakum I've mixed is getting them to dry without excessive dry times.
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From Salopian: "Here you go boys, Purdey's London Finishing Oil For Darkening, Filling & Polishing All measures are in English (UK) 1/2 pint of Raw Linseed Oil 2 ozs of Plaster of Paris (Dental Quality) 1/2 fluid oz of Butter of antimony 1/2 Gill Spirits of Wine 2 teaspoons of Vinegar 1 teaspoon of Venice Turps. You can leave out the Antimony if you don't want to darken the wood. Leave out the Plaster if you don't need to fill the pores. That's what is in Slacum Oil." see also: https://www.doublegunshop.com/forums/ubb...e=0&fpart=1As for climate, England is fairly humid even if it isn't quite the bayou. I suspect drying times have more to do with ingredients and application than the atmosphere. nonetheless, I built a drying cabinet to have a little more control
Jim
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FWIW, for oil finishes, I find UV light does more to help drying that most other factors. I don't think it is drying so much as curing that is involved. A couple hours outside in the sun helps a lot (though dust/lint problems then become an issue).
_________ BrentD, (Professor - just for Stan) =>/
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Thanks! I saw that on the document but wasn't sure if it was it. Will boiled linseed work or does it have to be raw?? Another question is will the pure grain ever clear be the same as the ethyl alcohol? The last I made I heated up and cooked. Is this prepared in the same way? Thanks and sorry for all the questions.
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Hi
Does anyone here have any first hand experience with J.V. Howe's formula number 1? I would like to hear about it.
PhysDoc
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An old thread but this treasure trove deserves continuity. Thanks to Woodreaux for compiling all the info from various sources including the threads here that I've plowed through many times!! Some comments and some questions:
Dig's Red Oil. I had noted Dig mentioning "I find I get better colour from alkanet root steeped in raw linseed for several months - rather than using it in alcohol or turpentine, which dilutes it too much in my experience." So "raw" rather than the originally mentioned BLO.
Question: specifically for red oil, do people use raw, unfiltered edible flaxseed oil or refined linseed (flaxseed) oil? Refined is incredibly pale and steeping it with alkanet root produces a very low viscosity, bright red rather than red-brown oil. (At one point many years ago I purchased some red oil from Dig and it was markedly red-brown versus the bright red produced by the batch I did in 2016. I steeped 80g of alkanet root in 250mL each of food-grade flaxseed oil and walnut oil for a year. To this day it remains of very low viscosity - there's no way it would sit on the stock in the way the red oil does in the Purdey video - and bright red rather than red-brown. I'm actually afraid to try to use it. Damascus had suggested colouring it with Vandyke Brown Artist's oil paint.Thoughts?
Dig's Finishing Oil recipe:
Raw linseed oil – 16 oz Spirits of turpentine (best you can find) – 2 oz (Diamond G Forest Products produces a highly recommended version) Carnauba wax – 200 grains Venice/venetian turpentine - 2 teaspoonfuls Mix together and heat until it simmers. Simmer for ten minutes then allow to cool. (A small measure of modern terebine / Japan driers) Be careful it does not catch fire -!!!!
I changed BLO to raw and added the line in parentheses because Dig had noted later that he was experimenting with modern terebine and had later commented "The finish I am using at the moment with best results is with turpentine rather than terebine as a drier and raw rather than boiled linseed oil." ("Modern terebine" in the US would be something like Japan driers.) I was a little confused regarding the driers and what would be replaced with terebine given the two types of turpentine. The document clarifies this by having "2 Ounces Spirits of Turpentine or Terebine Drier." Thank you.
The Purdey formula provided by @Salopian doesn't contain any wax. When he posted the recipe he noted "You can leave out the Antimony if you don't want to darken the wood. Leave out the Plaster if you don't need to fill the pores. That's what is in Slacum Oil." (See post above from Woodreaux.) Yet later he commented "Artist's linseed obviously is more refined and if you are making personal amounts it has to be the way to go because the cost is relatively small. If you want a filling oil use the carnaube and the plaster of Paris. If you just want a smoooooooth finish just use the modified oil finish less the wax and silica." I note the "carnaube and the plaster of Paris" but maybe he purely meant the canaube in Dig's formula and the PoP in the Purdey one. I'm wondering whether the formula ought to contain wax, particularly as the folks at Purdey mentioned in their IG video that “It has a drier and it has some wax, and that’s about as far as we’re prepared to go” (Tom.) Thoughts?
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It might also be worth adding to the document the other red oil recipe posted by Salopian:
"Sheraton, the furniture maker used 'red oil' to colour mahogany. Here is a modified version of his 'red oil' recipe. Take 4oz of alkanet root, broken into short strips,as much opened with the hand as possible, so that the bark of the root which tinges the oil may fly off, steep in 1 pint of raw linseed oil to which you have added 1 tablespoon of the oil of the spruce, steep for a week and strain it through a cloth. This makes a strong colour, you may have to dilute the colour with more linseed oil to suit your need. Oil of the spruce I believe is turpentine."
However it seems that spirits of turpentine, aka turpentine, is quite different from "oil of the spruce". Apparently, turpentine oil is made from the resin of the pine tree, while pine oil or "spruce oil" is distilled from the needles. Turpentine is a volatile and flammable liquid, while pine oil is a relatively stable liquid.
Last edited by JJJ; 08/24/23 08:13 PM.
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FYI a discussion of Venetian Turpentine. It is a resin/balsam extracted from the Larch tree, Larix decidua, Pinaceae. HereNOTE: "There is a product called Venice Turpentine that is used for treating horses’ hooves and is a dark brown sludge because it is just rosin dissolved in a solvent. Rosin is the solid residue left after a resin has been distilled to yield the essential oil or spirits of turpentine; it is a very poor material and should not be used for oil painting." The ingredients list for Hawthorne Venice Turpentine, Pinus Palustris (Gum)- 65%, Turpentine Essential Oil (Larix decidua)- 20%, Mineral oil- 15%, confirms the point. 65% rosin. So the Hawthorne product doesn't appear to be 'proper' Venetian/Venice Turpentine. True Venetian Turpentine isn't cheap! Luckily not much is needed. http://www.sennelier-colors.com/en/Venice-turpentine_fiche_4242.htmlhttps://www.jacksonsart.com/en-us/search/?q=larch+venice+turpentinehttps://www.dickblick.com/items/sen...4e2dw4N2aFqczn9xHIWW1aABhLkaAicbEALw_wcB
Last edited by JJJ; 08/22/23 12:22 PM.
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An old thread but this treasure trove deserves continuity. Thanks to Woodreaux for compiling all the info from various sources including the threads here that I've plowed through many times!! I'm glad the 'digest' has been of use. I will gladly add the information from Sheraton. The other finishing world that I think compares well to guns is that of the luthier. Although violins and such are not exposed to the same kind of weather, etc, they do bear a great deal of handling and use. I might put a few of the very old violin varnish recipes in the 'appendix' of the digest at some point. I've been out of the shop more than I would like for quite a while now, but I do hope to get back to gun projects, including refinishing. Thanks for the affirmation of the time I spent on compiling the finishes. I would love to see any examples from anyone who has experience with any of the recipes.
Jim
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Hi Woodreaux, on reflection I suspect the reason for the oil of spruce in the Sheraton recipe may well simply be for its scent. Without that the recipe is similar to all others. I've done a lot of digging into this subject over the last week. It's useful, IMHO, to reflect on the art world and how and why certain of these components are used. Here are a series of notes I've taken thus far. * Linseed oil is a 'drying oil’. "Linseed oil is a triglyceride, like other fats. Linseed oil is distinctive for its unusually large amount of α-linolenic acid, which oxidises in air.” "Having a high content of di- and tri-unsaturated esters, linseed oil is susceptible to polymerization reactions upon exposure to oxygen in air. This polymerization, which is called autoxidation, results in the rigidification of the material.” Wikipedia* https://www.naturalpigments.com/artist-materials/choosing-drying-oil-for-your-art* One issue with linseed oil is its tendency to yellow over long periods of time. As a result, "Linseed oil use has declined over the past several decades with increased availability of synthetic alkyd resins—which function similarly, but resist yellowing.” * A ‘varnish’ is a combination of a solvent (eg turpentine) and a resin Resin (eg Venice turpentine) * Resin is added as a softener or plasticiser, to counteract hardness or brittleness in a varnish compound. (A small amount of beeswax can be used in the same way.) https://www.jacksonsart.com/blog/2022/03/10/larch-venice-turpentine-a-resin-not-a-solvent/* When a varnish is combined with a drying oil, it’s called a ‘medium'. A medium is a liquid that is added to oil paint in order to change the performance of the paint in some way. * https://www.malcolmdeweyfineart.com...iquid,the%20paint%20easier%20to%20blend.* Many companies now produce a range of artist mediums than vary in their drying time and other properties (eg viscosity) * Driers help speed up the ‘drying’ process of a medium. Wikipedia* Terebine driers, in the UK, is a blend of metallic driers formulated to speed up the oxidative drying of solvent-based oil and alkyd based paints, stains and varnishes. The US equivalent would appear to be ‘Japan drier’, another generic term, which is largely naphtha plus cobalt and other metallic components. The name comes from the 17th century European practice of "Japanning," a process designed to imitate Asian lacquerwork. https://www.facebook.com/UtrechtArt...ht-japan-drier-is-a-/10154485032236704/#* "With an alkyd resin base and the tendency to alter the appearance of oil colors over time, Japan Drier is not recommended for fine art use. When left to dry to a high tack, Japan Drier can, however, be used for gold and silver leafing.” "Driers made from lead, manganese and other proprietorial mixtures that do not wholly contain cobalt driers are to be avoided as they promote darkening and loss of flexibility." * Cobalt drier is strongly recommended as a drier for fine art oil painting. "Cobalt Drier is the only siccative that has been scientifically proven to be the least harmful to use for fine art painting. Cobalt Drier speeds drying of oil colors and oil painting mediums. Because it is extremely strong, Cobalt Drier should be used sparingly by applying it in drops. It should not be mixed directly into oil paints, but first mixed into an oil painting medium, which can then be added to the paint.” * A cobalt drier accelerates the drying time of linseed oil from 2-3 days to 1. See table of drying rates: http://langridgecolours.com/cobalt-...embrittlement%20of%20the%20paint%20film.* https://www.dickblick.com/products/...Fsearch%2F%3Fsearchword%3Dcobalt%20drierI'm not surprised that Dig switched to adding 'Terebine' driers. Without a drier it takes linseed oil 2-3 days to 'dry'. I've made up a batch according to his original recipe (ie with the spirit of turpentine acting as a solvent alone) and will be adding a cobalt drier in the coming days to speed things up. Hopefully these notes are useful to some! EDIT: this remark in the Langridge page is informative: "Cobalt Driers cannot speed the drying of artists’ varnishes as they contain no oil. Artists’ varnishes dry by evaporation of the solvent." So if I look at Dig's original recipe, we have, I believe, a varnish - the larch resin (Venice turpentine) and carnauba wax dissolved by a solvent (spirit of turpentine) - mixed with a drying oil (linseed oil) to create a 'medium'. It has no drier accelerating the 'drying' of the oil. The solvent will dry by evaporation, but the oil drying is by polymerization (with exposure to oxygen). A solvent won't speed polymerization (although in oil painting it does thin out the medium, makes the paint leaner, and thus the paint will dry faster than a thicker, more viscous, non-dispersed, more oily paint film). But the amount of solvent needs to be significant for this to effect. *** So our gunstock oil needs a drier to accelerate this polymerization process if we aren't to wait 2-3 days between coats (or we wish to have access to a tacky film (which is wiped off) to help speed the filling of grain. Hence the change to using Terebine drier. (I'd likely keep the solvent.) The cobalt drier mentioned above is very powerful. The recommended dilution is a mere 1% which is about a teaspoon addition for Dig's original formula. *** If you look at the table in the Langridge link above you'll see that even a 'General Medium' of 1 part Linseed Oil + 1 part Gum Turpentine has an approximate drying time of 2 days. That's a 1:1 ratio. The ratio of spirits of turpentine to oil in the original formula is 1:8. ("Times listed are for paint films reaching a non-tack surface and not for complete through-film drying.")
Last edited by JJJ; 08/28/23 07:58 PM.
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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.
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Boxlock
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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.
Last edited by JJJ; 09/10/23 09:52 AM.
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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.
Last edited by JJJ; 10/22/23 09:08 AM.
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Woodreaux, earlyriser |
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Sidelock
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Sidelock
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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
Jim
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earlyriser |
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Sidelock
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Sidelock
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I apologize for not responding more completely before. You have done a lot of work and brought up many interesting points and additions or corrections to the information I had seen before. I would like to reply to much if not all of what you've brought up, and I'll start with this later point about 'rose pink'. I think you will find "rose pink" is made by "precipitating chalk or whitening with decoction of Brazilwood." Thank you for finding that reference, because I think that it sort of clears some things up for me-- starting with why things get so confusing when the older sources describe colorants and such. But it also finally demystified this one element, and I have now found some sources for buying rose pink, if one were so inclined. My summary (with additions from other sources) is as follows: - "Pinks" are a kind of lake, and may be of yellow, green, or red hue. - "Lakes" are pigments made by precipitating a dye with an organic, inert binder. - "Rose Pink" is a kind of lake with coarse texture and rose color, e.g. whiting and 'brazil wood' coloring. - "Brazil wood" can refer to several species, but is most precisely the common name of Paubrasilia echinata, which was previously classified as of the genus Caesalpinia. "Western" Brazil wood, aka pau brasil, aka pernambuco, is prized for both pigments and, more commonly today, bows for musical instruments. The color derived from Brazil wood extract varies depending on the mordant used to make the pigment. The Brazilwood tree is vanishing along with the Brazilian rainforest, which is the only place it grows, so most Brazilwood pigments sold today are derived from the related (and non-endangered) Asian trees of the genus Caesalpinia, aka Eastern Brazil wood or sappanwood. So, if someone wanted to produce a true Rose pink today, the closest they might come would be using whiting and sappanwood extract. Or one could buy one already made such as this I've started editing the Slacum Digest to add this info and make corrections. Some screenshots from the referenced book:
Last edited by Woodreaux; 03/07/24 03:57 PM.
Jim
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Sidelock
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Sidelock
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It has been a while since I have updated the Slacum Digest, and I still need to make some corrections/additions, including some made by JJJ above. ArtLavely's questions re: alkanet prompted me to look at the Digest again. For those who are interested, below is the link to the google docs file, which I will continue to update as I learn more and have time. (note: the table of contents is out of date, and I'll correct that at some point). Traditional Double Gun Finishes
Jim
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