Dear Martyn, My comment on the Stand Oil was from your most recent email on the topic , if I misunderstood it I apologize. I may not be able to access your earlier posts as I'm not active on the list, and emptied my computer about a year ago. I now save everything as I have a new system. I am interested in the links to the Strad techniques. I tried to confess lack of direct knowledge on the finishing of the lute top, but being a normal pontificator (Murph Says) I tried to offer thoughts. I look to be corrected, I like to learn. I have a good knowledge of the use of finish on woods as I am a wood turner who makes pieces from both seasoned and green wood, and hollow forms with walls of about 1/16. But these skills don't carry over to the musical instruments. the only commercial product I use is WaterLox, a combination of tung oil, some resins, and mineral spirits. It is a water-proofing designed in the early 20th C. for boats and piers - but not a hard sealant. Where we might disagree is the matter of coating versus a finish that soaks into the wood. For my work I prefer the soaking in rather than the coating, I think of the wood as wanting to remain in contact with the changes in moisture around it, but with a bit of a slow barrier to change. A hard coat, in general, can be cracked and invaded - and that can cause a differential moisture absorption or release. I'd like to look at the Strad links, although some current research attributes the sound of the Strads and Amatis more to the tight grain wood they had available in the Little Ice Age than the finishes they applied. That is open to argument, and probably is a combination of both. One more point. When I turn a bowl or other piece from "green wood", and by green wood I mean any wood not cut and kiln baked. I have turned pieces from wood cut and dried for three years and it is still living. Oops, broke the sentence. When, etc., the wood will warp as I turn it. It is a pain and a joy, one has to finish the turning quickly then wait to see what final shape it takes. No finish will stop the warping, and the chosen finish will enhance it. Hope to hear back on your thoughts. Best, Jon
On 1/24/2015 7:23 AM, Martyn Hodgson wrote: Dear Jon, This isn't really right. If you look at the earlier communications (in the archives of this list) you'll see I specifically cautioned against the use of modern commercial Stand Oil which, as you say, is generally heat treated Linseed oil and doesn't seem to ever harden off after application. Stand oil was originally simply Linseed Oil which was partly oxidised (thus becoming more viscous) by being allowed to stand in dishes. You can easily do this yourself - it takes a few months to get to the required consistency. The point is that it doesn't sink into the wood particularly but leaves a thin surface coating which, being already partly oxidised, soon hardens ( a few days) into and invisible coating resistant to moisture and the like. But plse look at previous postings on the matter and on links to Strad's methods. MH __________________________________________________________________ From: Jon Murphy [1]<j...@murphsays.com> To: Paul Daverman [2]<daverman.p...@sbcglobal.net>; [3]lute-builder@cs.dartmouth.edu Sent: Saturday, 24 January 2015, 11:49 Subject: [LUTE-BUILDER] Re: Lute top finish/treatment I haven't worked with lutes for a long time, and should probably drop off the list - but I like reminiscing <g>). I'll venture an answer, I do work still work with harps. Wood is never dead until it petrifies, it always takes in or gives off moisture depending on the environment (humidity and temperature). If you don't treat it at all it will be more susceptible to the changes in atmospheric conditions, but if you seal it then it can't "breathe". I wasn't familiar with the Stand Oil that Martyn mentions, but just Googled it and see it is a pure linseed oil heat treated. That fits my criteria. You mention a beeswax concoction, I am familiar with them from my wood turnings as I make several "concoctions" for different purposes. The beeswax concoctions at the simplest are a mixture of pure beeswax and generic mineral oil - but could be mixed with a vegetable oil (like linseed or tung). The tung adds color, the linseed doesn't. Your purpose in treating your sound board (the lute top) is to maintain its flexibility and sound production. The lute, like the guitar and violin (each to a greater or lesser extent) produces its sound in combination with the enclosed body of the instrument. The function of the sound board is somewhat modified by the nature of the transmission of string vibrations through a bridge over which the several strings are in contact with the sound board. That sounds gratuitious, but the harp that I deal with is quite different. The sound transmission of the harp is almost entirely from the vibrating strings in air, the function of the sound board (top), which is under tension from each string, is to pass the sympathetic vibrations from one string to another by direct vibration. The bridged instruments, like the lute, separate the sounds and produce the fullness in the body and top by combining them there. I could put a sealing finish on a harp sound board (athough I wouldn't, it would reduce the sound a bit), but not on a bridged instrument. The sealant stiffens the soundboard and it is a part of the sound in a bridged instrument. I think you should treat the sound board (the lute top) on both sides. I wouldn't use a varnish, it soaks in but hardens. I certainly wouldn't use a shellac as it is a surface coat and stops the breathing (although I do use a home made shellac compound with mineral oil for some pieces). You want something that allows the "living" wood fibers to absorb or give off the moisture, but not too fast. If you use a pure oil, like the Stand Oil, you would want to refresh it now and then.. Here is a pure speculation, and I leave it open to suggestions. A gentle sealant like one of the beeswax (or other wax/oil) concoctions for the underside of the sound board and a pure oil for the topside. Inhibit the drying of the internal wood cells through the internal body, but don't block it. Once the instrument is built you can't change the finish on the inside. Use an oil on the topside, and reuse it. Best, Jon On 1/23/2015 6:59 PM, Paul Daverman wrote: > I am wondering if some of the builders would be gracious enough to > weigh in on their treatment of the lute top. Some say absolutely > nothing should be put on the top. Others say varnish. I believe > Lundberg had given a recipe for a bee's wax concoction. I'm curious if > there is a consensus or standard. > > > Thanks, > > > Paul > > -- > > > To get on or off this list see list information at > [4]http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html -- References 1. mailto:j...@murphsays.com 2. mailto:daverman.p...@sbcglobal.net 3. mailto:lute-builder@cs.dartmouth.edu 4. http://www.cs.dartmouth.edu/%7Ewbc/lute-admin/index.html