The Talking Machine Forum — For All Antique Phonographs & Recordings

This subject has been discussed frequently lately with several different approaches to solving the problem of removing a swollen bearing from the saddle without damage. My purpose here is not to condemn any other method that has been discussed because it is apparent that they do work. I chose another method of bearing removal because of my aversion to any method that might cause damage. There are now 3 Edison phonographs in my collection that have swollen bearings along with frozen mandrels. I have been a tool-maker for over 35 years and have extensive experience working with cast iron. As others have already stated cast iron is strong but brittle because of its granular structure so putting any kind of force on it is not a good idea. One person has successfully removed 10 swollen bearings by gently tapping off the mandrel with a block of wood and using other methods to extract the bearing. Not wanting to risk bending the shaft or breaking the saddle by tapping the mandrel off or resorting to using acid my choice was to use a gear puller to very gently and easily remove the mandrel with no chance of bending the shaft. Then a tool was constructed to once again, easily and gently cut the swollen bearing out of the saddle using a cordless drill to drive it I tried the tool out today on one of my Home phonographs and I must say it worked beautifully cutting the bearing out in less than 5 minutes. Now the shaft is free and can be disassembled, cleaned and the mandrel pressed back on. There is just a very thin shell of the bearing left in the saddle and that will come out very easily. I was going to try and make a video of the whole process but my wife was busy today so no video. Here are pictures of the tool, the tool mounted on the shaft of the Home and the bearing saddle after the tool cut through the bearing.

Very nicely done !

Is that a hole saw that you mounted to a shaft? Or, did you make the saw too? Lee Kirk was making and selling core drills like that years ago. Sadly, he passed away a few years ago.
Dave

Very interesting and effective method. You, being a toolmaker have an advantage that I can only wish for, so I must employ other methods. When I retired 14 years ago one of my goals was to learn toolmaking and invest in a small lathe and vertical mill but alas, life intervened and it hasn't happened and now probably won't. We have evening woodworking classes at high schools everywhere around here but unfortunately no "Machine Shop for Geezers".

Jim

Dave D wrote:Is that a hole saw that you mounted to a shaft? Or, did you make the saw too? Lee Kirk was making and selling core drills like that years ago. Sadly, he passed away a few years ago.
Dave

Dave: Yes that is a hole saw attached to the shaft. Since I only have 3 machines to do my objective was simplicity that's why a ⅝" hole saw was used. The body of the tool is made from ¾" cold rolled steel turned down to ½" on one end for mounting in a cordless drill chuck. The other end is bored out to .594 to accept two plastic bushings machined out of Delrin that are press fit into the bore. The Delrin bushings have about .001 clearance with the mandrel shaft to keep the tool centered and rigid to reduce chatter and wandering. The bushings are about ¾" long and have space between them when installed. Bt the way, Delrin is a high impact plastic that has a low coefficient of friction and it won't mark the shaft that's why I chose it. The hole saw is a snug slip fit into the bore for about ½" and has been tack welded in 4 places to keep it in place.

Thanks for the consruction notes! I will place this on my own project list.
Dave

I looked for the gear puller that was used to remove the mandrel from the Edison Home pictured in my other post. The next machine up is a machine that is new to my collection, a beautiful Edison Triumph model E with a Music Master horn. This is one machine other than an Edison Opera that I've always wanted so no chances will be taken with its restoration. Since the puller couldn't be located it was decided to just go ahead and make a dedicated mandrel extraction tool. I'm going to give it a try this weekend and will post pictures incase anyone wants to copy it.

I can't wait to see your mandrel pulling tool. I always enjoy seeing shop-built tools.
Dave

Dave D wrote:I can't wait to see your mandrel pulling tool. I always enjoy seeing shop-built tools.
Dave

Dave: The mandrel puller works great on the Edison Home however it was a near disaster on the Edison Triumph. When I inspected both machines it looked like the mandrels were both constructed the same way on each one but that is not the case. With the great success on my Edison Home couldn't wait to try it on my Triumph so it could be put back in playing shape. The tool was mounted on the Triumph mandrel and everything looked fine so a little pressure was applied, everything seemed OK but the tool was removed just to check everything over before proceeding. With the tool off everything looked fine so it was remounted and pressure applied once again. All of a sudden there was a "pop" and after looking things over I could see a disc that looked like it had been soft soldered to the mandrel had popped off. Took the tool off and inspected the damage and it looks like it can be repaired but the mandrel is not off and the shaft is still stuck. Does anyone know how the triumph mandrel comes off? It certainly doesn't seem to be pressed on like the Home. Here are pictures of the tool but once again this tool does not work on a Triumph!

Thanks again for sharing your designs. So sorry to hear of the problem with the Trimph mandrel.
Dave