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Discussion in 'Basses [DB]' started by Martin Sheridan, Dec 11, 2003.


  1. Martin Sheridan

    Martin Sheridan

    Jan 4, 2001
    Fort Madison, Iowa
    Bass Maker
    Makers and players who have seen them know that the instruments made during the "golden period" between 1550 and 1750 in Italy have a unique look. It's often attributed to the varnish, but it seems to have more to do with the ground; something they put on the wood before varnishing. I've used many different grounds some commercially bought and some cooked up in the shop, and it seems like every instrument gets a different treatment. Someone once described this ground as having the look of a soft light coming from the wood under the varnish. I've noticed that sometimes this light is on and sometimes it isn't.
    I'm not sure if there was something different about the ground or just the way the wood itself reacted to it, or maybe the way the light was hitting the instrument that day. The closest I've come to that look was when I rubbed some oil varnish directly into some aged and darkened spruce and maple. However on my last visit to
    the Shrine to Music Museum, most of the instruments did seem to have a golden yellow color applied under the varnish. The exception was the Stradivari Harrison violin.
    I've tried gumboge, coffee(it tastes good too),
    commercial preparations, potassium silicate and sodium silicate and I'm thinking about trying the Fulton Propolis soap. Karl Roy told me that before Sacconi died he told him that he had changed his mind about potassium silicate and thought it was washed linseed oil and a very small amount of bees wax(sounds like grandmas formula!). I'm just now finishing a cello and I'm really tempted to try it.
    I think the varnish researcher Gary Bease believes they just put an oil varnish right over the wood and that they either put the instruments in the sun long enough to tan them, or the wood darkening was just something that happened over a period of time. I've always found it hard to believe that they could have kept the instruments off the market long enough to tan them. They had to eat, same as us. Although when Stradivari died I believe there were still 70 or 80 instruments in his shop, but I don't think most makers would have had the luxury to make so many and hold on to them.
    Sometimes I'm not even sure that it matters,or that we can't come across something entirely new that looks as good or better. Yet when I see an authentic example from this period I find them incredibly beautiful.
    Anyone want to share the secret, or their favorite sauce?
     
  2. Maybe they used a heat activated blush. I build flintlock rifles and one of the main finishes used for maple in the 18th century was aqua-fortis which is Nitric acid with metal filings disolved in it. You apply it to the wood and after it dries you "blush" it by heating a piece of metal and holding it about 4" above the wood. This will darken the wood and bring out the figure. Aqua-fortis would be too dark for a violin or Bass but I am sure there are other agents that could be used to do what you speaking of.


    Joe
     
  3. Let us know how the propolis soap ground works for you. I have a bee keeper friend who says he has a coffee can full of raw propolis that he has been saving for me. I asked about the Propolis ground on TOBI-L and no one seemed to know much about propolus as a ground. They did however show a marked dislike for the Fulton propolis varnish. Are you planning on puting an oil varnish on top of the ground?

    Have you or Anton played around with the David Rubio mineral ground. From what I've read, it comes closer to the composition found in the Strad and other Cremona samples examined with the scanning electron microscope than any other ground examined so far.
     
  4. Martin Sheridan

    Martin Sheridan

    Jan 4, 2001
    Fort Madison, Iowa
    Bass Maker
    Anton tried the propolis soap and thought it ruined the sound, but I don't know if he tried it on more than one instrument. It does have the right look. He also used the Rubio ground but doesn't think it's right, but uses something similar of his own composition. He changes the "sauce" as he calls it so frequently that I can't keep up with it.
    I've read that some of the tests have found a mineral ground just below the varnish and some haven't. That doesn't surprise me. Maybe they experimented as much as we do. The mineral ground seems to make the instrument very dark, but after you put on the varnish it looks right under the varnish, actually lighter after the varnish is applied. I'm interested in propolis because Sacconi said that you could rub the varnish(or even a spot where it had rubbed off?), and you could smell propolis. However, if the washed linseed oil and beeswax idea is right that would also explain the propolis smell.
    Also, I love the smell of propolis, so I'm thinking of adding a little of the commercial Hammerl propolis oil varnish to my varnish just because it smells so good. I attended a cello conference in Illinois a couple of months ago and Bill Lee was there with some of his cellos. After they had been out of the cases for awhile, the whole room smelled like propolis. I think they might be using it on the inside. Alcohol/propolis varnish takes forever to dry...like months. The commercial propolis oil varnishes only contain a small amount for the same reason.
    I'm only using oil varnish.
     
  5. I've read that many makers using the Rubio ground are using rosin oil after the ground and say that it becomes total transparent. I've never tried rosin oil. Do you know anything about it?
     
  6. Martin Sheridan

    Martin Sheridan

    Jan 4, 2001
    Fort Madison, Iowa
    Bass Maker
    I have to correct part of my earlier comment. The reason the instruments look so dark is that we are using a kind of glazing method.
    We're also using rosin oil, but I'm not sure how, since I don't varnish the instruments made here. I just do my own when I have time. I use a glazing method with artist oil colors.
    Anton is a great experimenter, and anything I might say or know about his methods won't be true next week!
    Kremer Pigments has a web site, and their catalog gives complete instruction on the Rubio method.
    The Southern California Association of violin Makers has a web site where Fulton tells how to make the propolis soap.
     
  7. I've got the two Fulton books. He goes into more detail in the books than in the article on the SCAVM site. Bill Fulton published the Propolis ground/varnish several years before he came up with the Terpene varnish. I'll have to go back into the book and see if Bill recommends the propolis ground under the Terpene varnish. I like the Terpene varnish.
     
  8. Martin Sheridan

    Martin Sheridan

    Jan 4, 2001
    Fort Madison, Iowa
    Bass Maker
    I always meant to order that book. I respect the work that Bill has done. Did he write about the propolis soap in the book? I was under the impression that was something new?
     
  9. Bill Fulton's varnish book has a publication date of 1988. The first part is all about Terpene Varnish. The second section is about Propolis and was originally published as a stand alone book several years before the Terpene varnish. I met and talked to Bill at the CAS/MVA joint meeting in Dearborn, Mich in 1996. There wasn't much discussion about Propolis at that time. Everyone there wanted to talk to him about bending plates and Terpene varnish. I would guess that half of the members attending used or were thinking about using Terpene and the other half wanted to know more about bending plates. I think Anton has or had a copy of Bill video on plate bending.
    I did get out the book and scanned through it. Apparently the Propolis soap is part of the Propolis varnish as well as the ground. I found a reference where he does recommend using the Propolis soap as a ground under his Terpene varnish.
     
  10. nicklloyd

    nicklloyd Supporting Member/Luthier

    Jan 27, 2002
    Cincinnati, Ohio
    Holy jeepers, you guys are getting along!

    You'se ever use "wheat size" as the ground? Flour, water, tea, and drano. It's pretty much the same recipe in Weishaar's book... I've been using it, and it does a great job. Seals pores and brings out figure. Then it's just a couple of thin garnetlac coats after that.
     
  11. Ah come on Nick. You knew that had to be something in the violin/bass world that we could agree on. Enjoy it - it may be a while before that happens again!

    !!!! Drano!!!! I wonder how Strad cleaned his drains?
     
  12. Martin Sheridan

    Martin Sheridan

    Jan 4, 2001
    Fort Madison, Iowa
    Bass Maker
    He probably used propolis soap to clean the drains, but only propolis that came from the immediate area around Cremona.
     
  13. While taking a brief rest from our rather heated discussion of weight and A0/B0 and heavy extensions, and subjecive bulls**t, etc. I took time to re-read the Fulton varnish book. After comparing the section on propolis varnish (orginally published in 1969) with the the extract from Bill Fulton's 1997 SCAVM article on the propolis ground, I have concluded that the 1997 SCAVM article contains the best and most up to date info on the prepartion of the propolis soap ground. So.... don't buy the book unless you want to know the history of the propolis varnish, Fulton's ideas on the recreation of the Cremona varnish, and everything about the prepartion and use of the Terpene violin varnish. I'm hoping to get my coffee can of raw propolis this week and I'll start makin' soap soon.
     
  14. Martin Sheridan

    Martin Sheridan

    Jan 4, 2001
    Fort Madison, Iowa
    Bass Maker
    Let us know how that turns out. It does have a very authentic look, but also how it affects the sound, even if your opinion is subjective(hee,hee).
     
  15. Well, I just received the raw propolis from my friend the bee keeper. It is going to take a lot of faith to believe that this stuff will eventually produce a beautiful yellow ground. As it is now, it is just simply vile looking and smelling "rocks". The book says to place it in alcohol for two weeks and then to filter out the gook. We'll see! Stay Tuned.