moondog Posted November 12, 2009 Report Share Posted November 12, 2009 Hello all, I'm very new at this so i could use all the help i can get, would anyone please help me find the answers to the following questions. 1). what is the best way to clean out the marrow, sinews, and fat from a cattle schin bone? Should this be done before or after soaking it in water and soap? Also, is it bad to boil the bones with the meat and fat in it? if so what is the best way to get the oils out so that it doesn't leach into the rest of the bone? 2). After my bone is prepared and I have a pattern carved out, what is the best way to sand my pieces to a smooth surface. the areas that i am looking for in particular are the insides of curves and rounded areas where a flat sand paper cant get to. I've heard people suggest wet sand paper, but i'm not sure how to do this. 3). What is the best way to polish and whiten the finished piece? Link to comment Share on other sites More sharing options...
Yuri Posted November 12, 2009 Report Share Posted November 12, 2009 I use a lot of bones (not only cow), so have a bit of experience. What I do is when I get the bone, try to clean it as soon as possible. The first thing is to cut off the two ends. The line where they are cut off should leave no spongey bits in the inside , but only clean bone. Next step is to press out the marrow. Normally with cowbone it should come out in one or two solid pieces. Next put it in a pot of cold water, and put the pot on the range to boil up. After the water starts boiling, I take the pot off immmediately. Some carvers leave it on for longer, some for as much as an hour, but I found that the bones will tend to get more brittle the longer they boil. Now is the time for the scraper, to clean the outside of the bone. A knife will work, but I use a specially made sraper, which is simply an old triangular file set in a handle, with the file teeth ground off, and the edges ground sharp. Works like a dream. At this stage you should be left with a tube of clean bone. You can put it into another pot of clean water, and boil it up again, to get rid of the fat still clinging onto it. If there is a bit of spongy stuff left in the middle of the bone, carve it out, before re-boiling. If you do not, it will impregnate the bone with fat very quickly. (there is fatty matter throughout this spongey part.) As to the sanding, well, folded up sandpaper held in the fingers still works the best. There is no substitute yet discovered for this kind of work that is better than skillful fingers. When the carving is complete if there are some fatty splodges in the bone, white spirit is the stuff to use. Now, I'm in New Zealand. What is called white spirit here is not apparently called the same everywhere else. It's a petroleum product, not an alcohol, that's all I can say. It is also very flammable. I'm not entirely sure, but I think it might be the same as lighter fluid. They use it for camp stoves, too. Degreases bone very quickly. For bleaching you can't beat Hydrogen Peroxide. (of platinum blonde fame) This comes in different strenghts, use the strongest you can get. (My way it's 6% solution) I tear a piece of cotton wool big enough to envelope the whole carving, soak it with the Hydrogenperoxide, wrap the carving in it, then wrap the whole thing in a clingfilm strip, so it doesn't leak out, and leave it for a few hours. The warmer it is, the quicker it works. Link to comment Share on other sites More sharing options...
moondog Posted November 12, 2009 Author Report Share Posted November 12, 2009 I use a lot of bones (not only cow), so have a bit of experience.What I do is when I get the bone, try to clean it as soon as possible. The first thing is to cut off the two ends. The line where they are cut off should leave no spongey bits in the inside , but only clean bone. Next step is to press out the marrow. Normally with cowbone it should come out in one or two solid pieces. Next put it in a pot of cold water, and put the pot on the range to boil up. After the water starts boiling, I take the pot off immmediately. Some carvers leave it on for longer, some for as much as an hour, but I found that the bones will tend to get more brittle the longer they boil. Now is the time for the scraper, to clean the outside of the bone. A knife will work, but I use a specially made sraper, which is simply an old triangular file set in a handle, with the file teeth ground off, and the edges ground sharp. Works like a dream. At this stage you should be left with a tube of clean bone. You can put it into another pot of clean water, and boil it up again, to get rid of the fat still clinging onto it. If there is a bit of spongy stuff left in the middle of the bone, carve it out, before re-boiling. If you do not, it will impregnate the bone with fat very quickly. (there is fatty matter throughout this spongey part.) As to the sanding, well, folded up sandpaper held in the fingers still works the best. There is no substitute yet discovered for this kind of work that is better than skillful fingers. When the carving is complete if there are some fatty splodges in the bone, white spirit is the stuff to use. Now, I'm in New Zealand. What is called white spirit here is not apparently called the same everywhere else. It's a petroleum product, not an alcohol, that's all I can say. It is also very flammable. I'm not entirely sure, but I think it might be the same as lighter fluid. They use it for camp stoves, too. Degreases bone very quickly. For bleaching you can't beat Hydrogen Peroxide. (of platinum blonde fame) This comes in different strenghts, use the strongest you can get. (My way it's 6% solution) I tear a piece of cotton wool big enough to envelope the whole carving, soak it with the Hydrogenperoxide, wrap the carving in it, then wrap the whole thing in a clingfilm strip, so it doesn't leak out, and leave it for a few hours. The warmer it is, the quicker it works. Hey yuri, thanks a lot for your help. I will give your suggestions a try. How do you buff and shine your peices? Link to comment Share on other sites More sharing options...
Janel Posted November 12, 2009 Report Share Posted November 12, 2009 I moved this thread to Techniques, because there is another active thread discussion on the same topic. Janel Link to comment Share on other sites More sharing options...
Yuri Posted November 13, 2009 Report Share Posted November 13, 2009 The buffing and shining question. I personally don't particularly like the highly polished finish. To my eyes it decreases the appeal of at least sculptural pieces. Sort of like the diffrence between glazed porcelain and bisque porcelain. I far prefer the bisque when it comes to sculptures. Anyway, once again it's down to elbow grease, simply keep on going with finer and finer sandpapers, until you get to the finish you like. At some stage it's possible to replace it with steel wool, again in the appropriate grade, but it is not appropriate for all work, as it tends to take the edges off very delicate carving. If you really like superfine finish, I sometimes in the past used what here, in NZ is marketed as "Brasso", it's a polishing liquid for brassware. (there is "Silvo", a finer grade.) I simply soaked a rag with it, let it dry, and then use it as a polishing cloth. (but I have to say, that was quite a while ago I last used it...) Link to comment Share on other sites More sharing options...
jsjs Posted December 3, 2009 Report Share Posted December 3, 2009 Hi, Just found this, it relates to preparing musical instrument saddles but I thought it might be relevant to the group http://www.bearmeadow.com/build/materials/...bone-clean.html Link to comment Share on other sites More sharing options...
Baz Posted July 5, 2011 Report Share Posted July 5, 2011 I checked out the Luthier's notes (very comprehensive thanks jsjs) As he/she says - may be a bit too much for us ordinary carvers, but well worth the read - I got a lot out of it. As far as finishing goes - whatever pops your cork, but I keep a finished piece (after sanding) in my pocket and just rub between fingers and thumb. you'll be surprised at the result. A word of warning, make sure it's your jacket pocket or you might get the occasional funny look I also do a lot of reading, which the ideal time also to do a bit of "guilt free" rubbing - TV time is good too as I find that artificial light by itself is not bright enough Anyway that's my ten cents worth Cheers Barry Link to comment Share on other sites More sharing options...
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