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Re: My first talking machine and info on it's restoration
Posted: Tue Nov 24, 2020 5:42 pm
by dzavracky
Great job! You should definitely be proud of the work you did on this machine
Cheers
David
Re: My first talking machines and info on their restoration
Posted: Fri Nov 27, 2020 1:48 pm
by Herderz
Thanks dzavracky. I got my records that I got off ebay today. 8 Margret Whiting records in a album for $15 delivered. All in great condition.
I also sorted through all the needles that came with the machine to Kul-out used from new using a 10x sight glass that I have. 75% of them had been used.
I played 4 songs from the set and man it sounds clean with no distortion for mono-analog recordings this old. Very loud for my shop with only loud tone needles. I can see I am going to have to get soft tone needles for when I move it into the house.
Re: My first talking machines and info on their restoration
Posted: Fri Nov 27, 2020 3:20 pm
by Herderz
After playing the new records on the cabinet machine I played one on my Birch model 700 portable that I have had for years. Although not as good of sound quality the volume was lower and it still ran pretty good.
I decided to restore this machine also, having not done anything to it after buying it years ago at a yard sale for $30 and getting some help from a talking machine friend and clock collector on setting the reproducer angle. This will be while waiting to come across a nice horn project. It has a stained canvass case with much wear over the years with leather handle which is in good shape.
It has a maple "I think" motor board, Card board or paper horn with the exit out the backside of the playing surface. All the hardware is there just needs a little detailed attention.
The motor is a General Industries Motor, with a 1 spring main drive. It has a casting number but I have no clue what it means, 19602? I looks in good shape but it has wear somewhere in the gear train. Just a little noisy compared to my rebuild of the Meisselbach motor on the cabinet. I am sure I will find it upon breakdown and cleaning.
And here we go!
Re: My first talking machines and info on their restoration
Posted: Sat Nov 28, 2020 1:56 pm
by Herderz
I broke down the motor and cleaned everything up. It was not muk'd up as bad as the Meisselbach on my other machine. It still took some time to clean every gear tooth and inspect. The spring drum gear has slight wear or burring on the outside face but this is common on spring drives due to the gear having to be on one side of the spring or the other. This causes deflection of the gear mesh due to force trying to push the gear sideways (cocking) instead of a parallel mesh. I just take a small stone and knock the burr off the side of the gear. The fiber gear is in good shape and no noticeable wear at the top spindle bore with the shaft being held into the casting by a spring clip on the top side. These type clips are very hard to get off without tapping the spindle through the casting to remove, it is a pot medal casting and that can break. No problem with the main spring so I didn't crack open drum.
Re: My first talking machines and info on their restoration
Posted: Sat Nov 28, 2020 2:02 pm
by Benjamin_L
You did a phenomenal job cleaning up the cabinet, be cautious with later 40s-50s records.
Acoustic machines aren't great with later 78s as they wear down faster and can over power the mica diaphragm. (They're designed mainly for acoustic records before the 1930s.)
Re: My first talking machines and info on their restoration
Posted: Sat Nov 28, 2020 2:21 pm
by Herderz
After polishing each gear shaft pinion ends and the bores and bushings I checked the clearances and everything looked good put the first gear off the drum drive gear. It had quite a bit of wear. You can see the gap between the pinion shaft of the gear and the bushing at the bottom, that is not a shadow, in the next pic. You can also see at the top the burring that has occurred over time. It is curling the brass out of the bore. This is a sign of poor lubrication over time.
The bore hole is oblong showing how the force of the train has pushed or wore the bore in the direction of the spring force.
Re: My first talking machines and info on their restoration
Posted: Sat Nov 28, 2020 2:30 pm
by Herderz
Thanks Benjamin L. I did not know that. Is that why they went to metallic diaphragms?
Re: My first talking machines and info on their restoration
Posted: Sat Nov 28, 2020 2:47 pm
by Herderz
After polishing the gear pinion on the lathe and measuring it at 4 mm. I needed to replace the worn bushing. I have many sizes of bushings being in the clock world so I needed a bushing with a 4.1 mm. bore and a 6.5 mm OD. I had a 4 mm. bore so I reamed it to 4.1 mm. with a broach and the 6.5 mm OD is a standard in the clock world also.
I removed the old bushing and pressed the replacement in. I assembled the gear back into the plates with only the spindle gear to check gear mesh and drag. It came out perfectly.
Re: My first talking machines and info on their restoration
Posted: Sat Nov 28, 2020 2:50 pm
by Herderz
I reassembled the motor, oiled and greased it and wound it up and let it run down a couple of times. I think it will run smoothly now.
Re: My first talking machines and info on their restoration
Posted: Sat Nov 28, 2020 4:54 pm
by VanEpsFan1914
This is probably one of the best restorations anyone has attempted on a Birch 500.
If you can rebuild the soundbox, it will play your 1940s records better than the upright phonograph.