farfel Report post Posted October 12, 2007 A friend of mine took the top off his student-grade fiddle to find the source of a rattle. The top looks awful thick, (maybe to make the instrument more durable for student use ?) I suggested that as long as he has the instrument apart, he might try to sand the top thinner and maybe it will sound a little better. If this makes sense, any suggestions about how thin it should be? Quote Share this post Link to post Share on other sites
FiddleDoug Report post Posted October 12, 2007 Did he find the source of the rattle? As for thinning the top- The top is not one thickness over the whole area. You should find out the appropriate thickness for various areas before thinning. Do you have an appropriate caliper (that reads in hundredths of a mm) to do the measurement? Also, finger planes and scrapers are the usual tools for the job. Quote Share this post Link to post Share on other sites
Andres Sender Report post Posted October 12, 2007 The top may or may not need to be of differing thicknesses in different areas depending on whose concept of which example of which maker it is, and how well that concept was executed, if at all. Unless the top is grossly over thick there is no guarantee that amateur thinning will improve the instrument, and without knowing what the arching shape is it is impossible to make a recommendation. Regraduation of the back is usually more effective in making changes, but again this depends on the model and the current state of the graduations. Oh and readings in .1 mm will do. Quote Share this post Link to post Share on other sites
Wm. Johnston Report post Posted October 13, 2007 I've never owned a caliper that can read hundredths of a millimeter and frankly I don't ever see myself buying one either. I would have no use for knowing the thickness of my wood down o a hundredth of a millimeter. I usually don't even measure the thicknesses while I am graduating a plate. I only check my thicknesses after I am done just out of curiosity. Without seeing the violin top in question its impossible to say whether regraduation would help the tone of the violin. Quote Share this post Link to post Share on other sites
Torbjörn Zethelius Report post Posted October 13, 2007 quote: Originally posted by: farfel A friend of mine took the top off his student-grade fiddle to find the source of a rattle. The top looks awful thick, (maybe to make the instrument more durable for student use ?) I suggested that as long as he has the instrument apart, he might try to sand the top thinner and maybe it will sound a little better. If this makes sense, any suggestions about how thin it should be? Make it no thicker than five mm's. Really, there's not enough information to say anything useful here. As for calipers, I could totally do without them. Quote Share this post Link to post Share on other sites
Craig Tucker Report post Posted October 13, 2007 quote: Originally posted by: farfel A friend of mine took the top off his student-grade fiddle to find the source of a rattle. The top looks awful thick, (maybe to make the instrument more durable for student use ?) I suggested that as long as he has the instrument apart, he might try to sand the top thinner and maybe it will sound a little better. If this makes sense, any suggestions about how thin it should be? This isn't the best idea if your friend isn't fairly experienced with either lutherie or general woodworking, but if it's an inexpensive, replaceable student fiddle - it sounds like something I might have done some years ago ;-0 First off, how thick is the top? if he's going to sand, he's probably got quite a bit of sanding to do - he might lose interest before removing two or three mm's - that's what usually happens. This (plate thicknessing or re thicknessing) is normally done with a small plane, gouges (which require some skill) and/or at least, a sharp scraper. If this is simply a typical thick Strad model student violin, he might want to think about going down to around 3mm ( and perhaps slightly thinner at the extremedies) and then see how that works. Some sort of measuring device should be used for this. It wouldn't be out of the question to go with a stopped drill press to mark an accurate depth. Calipers, or a depth marker may not be necessary for an experienced maker - but such a tool is pretty much required for an inexperienced one. The bass bar area will be problematic as usually the bar is removed for rethicknessing and then a new one is fitted. But now you might as well stop and start tooling up a bit because several simple but necessary things (tools and jigs) will be required. But he prolly blew the whole thing when he removed the top anyway... Quote Share this post Link to post Share on other sites
Lyndon Taylor Report post Posted October 13, 2007 I don't think regraduating and altering should be encouraged especially when rank amateurs are involved, youre assesed student grade fiddle might be a decent violin that you will damage the value of by altering it, I know there are a lot of people who say if the violin is cheap enough go ahead and alter it all you like, I disagree, in 600yrs an unaltered 20th Century Strad label will be worth more than a regraduated one, so who are you really doing a service to regraduating, certainly for the cost of a regraduation you could buy a better fiddle that's what I would reccomend, theres an old expression you can't kick a dead horse, thats what a lot of factory German and Czech 20th Century stuff amounts to, regraduating doesn't get rid of the lousy sound just moves them to different frequencies, still just as lousy most times, I hate to find an instrument I am working on has been regraduated, although if its cheap junk it doesn't bother me as much, still lets make regraduating and revarnishing, archaic practices of the past PPLLEEAASSEE sincerely Lyndon Quote Share this post Link to post Share on other sites
farfel Report post Posted October 13, 2007 He's gone this weekend at a bluegrass festival so I cant get in touch with him to ask more questions but I do remember that it is a Strad copy student fiddle, and it looks like the top was glued on with titebond! As best as I can estimate, it was about 5-6mm thick at the f-holes whereas my Maggini copy measures about 3mm at the f-holes. He does have a caliper that can reach all around the fiddle top. I'll give him your responses and let him decide what to do. I would sand the top to 3mm....what the heck, try it. He's a little "enthusiatic" and didnt think this through. I had to call him and stop him from removing the back after he removed the top! I think the source of the rattle was a loose top, which is why he removed it first. Thanks for all your help. Quote Share this post Link to post Share on other sites
Craig Tucker Report post Posted October 13, 2007 Clip; "but I do remember that it is a Strad copy student fiddle, and it looks like the top was glued on with titebond! As best as I can estimate, it was about 5-6mm thick " White or yellow glue is becomming standard, even for Pfretzschner/Roth student violins. Don't get me started. Quote Share this post Link to post Share on other sites
