Since my work with my old Buescher Eb is going so well, I decided to remove some of the numerous dents from it. These are all on the outer branches and range from a lot of little almost "pinhole" dings through some larger ones that are perhaps 2" long and about 3/4" wide. Some time ago, following some postings that Dan Schultz (http://thevillagetinker.com/) made in a thread on Tubenet, I acquired some of the material he recommended and these then sat dormant for almost a year. In particular, I got a Neodymium Super Magnet, 1.5 in x 1.5 in (Model ND069-1) from Magnet4less.com (about $47 including shipping) and a 1 7/16" chrome steel bearing ball from Bearingballstore.com ($8 + shipping).

A couple of days ago I started out by trying this approach on an old Martin baritone I got specifically to restore and practice on. I put on a pair of leather gloves (following other recommendations on Tubenet) and placed the magnet in one of those microfiber cloths that are readily available in auto stores, supermarkets, etc. for various kinds of polishing. Dumped the ball down the bell of the baritone and gingerly approached it with the magnet ... CLANK! That sucker is strong. (The best technique is to let the ball settle in some position, then apply the magnet to the horn some distance away and slide it toward where the ball is.) I then proceeded to carefully role out a shallow dent on the outer branch of the baritone. This was a huge success!! I then did several others, to the point that the baritone is now dentless, and with no mishaps. I managed to get the magnet off the horn by twisting it away from the surface and putting it safely in a plastic container, and then in a cardboard box with a very visible warning label attached: "STRONG MAGNET. STAY AWAY. DO NOT APPROACH WITH ANY ELECTRONIC DEVICE." (I am particularly careful about this because my eldest child has an implanted pacemaker and defibrillator, and he really doesn't need for the pacemaker to go into test mode or for the defib to trigger if not absolutely necessary.)

Today -- emboldened by my success -- I tried it on the tuba. The results so far are GREAT. I'm waiting on a 2" ball (ordered from Ferree's for even less cost, since I had to order valve guides from them anyway) to take on the lower bell section and bottom bow. But above the bottom bow I have at this point removed almost all of the dents, and the result looks fantastic.

Some observations:


  1. This takes a LOT of effort. At least this is true on "vintage" instruments. I'm sure it would be easier on my red brass Cerveny tuba (which at some point may get the treatment for its 3 little dings), but that will require greater care. These old horns seem to have quite hard brass, and numerous passes (30, 40, 50, or more) are required to remove a significant dent.
  2. The effort is mostly proportional to the depth of the dent, and not to its extent. So even tiny "point" dings can take a lot of effort. But they CAN be removed.
  3. I have been very careful to proceed slowly and with great caution. I don't want to be careless and get hurt with this magnet, and I don't want to mess up the instrument through a moment of incaution. But so far things are going very well I can't imagine how much it would have cost me to have these dents removed by a brass repair technician.


One challenge yet to be met is to remove a fairly lengthy flattened area under a guard strip on the outer wrap. I'm hoping that I can do this without removing the guard strip, but we'll see. And I'm looking forward to getting the larger 2" ball which I will use on the bottom bow and lower bell section.