8mm Forum: Pathe Gem

This is topic Pathe Gem in forum 9.5mm Forum at 8mm Forum.

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Posted by Terry Sills (Member # 3309) on September 05, 2015, 03:46 AM:

I have a 9.5 Pathe Gem which works ok but the motor "hunts", that is to say the speed varies. Does anyone know what governs the speed and how to adjust/cure this problem so that the speed remains constant?

Posted by Mike Shaw (Member # 4640) on September 08, 2015, 06:10 PM:

There's no adjustment for this Terry but if the machine as been laying idle for some time you'll find the original belt as gone hard and is out of shape...so replace....also if motor mounts are weak this can course problem....If belt the problem you will find original belt made out of fan belt material replace with 'O' ring of right size or else will pull motor mounts towards shutter.

Posted by Terry Sills (Member # 3309) on September 09, 2015, 02:17 AM:

Thanks for that info Mike. I will have a look at that.

Posted by Terry Sills (Member # 3309) on September 14, 2015, 01:34 AM:

Well it seems the belt is not the problem. The motors acts in the same way even without a belt. It seems to be a motor fault. Are there brushes on the Gem motor?

Posted by Vic Newey (Member # 5181) on December 27, 2015, 08:40 AM:

Did you find the fault eventually ?, I have a similar problem which I think is related to the speed resistance windings. Speed on mine only worked when the lever was far to the left but the motor kept slowing & speeding up again and I've just unwound mine and found it's broken in several places so presumably it's causing fluctuations in the voltage going to the motor.
I'm now looking for details of the correct wire to get to replace it as it's a simple job that just requires patience to get the windings tightly together.

Posted by Terry Sills (Member # 3309) on December 28, 2015, 02:40 AM:

Vic
No I didn't investigate further but what you describe sounds very feasible and is most likely the problem with mine. I will have to get round to it sometime soon. I have been very fortunate to obtain another Gem that came with the original box and instructions- very unusual to find in such good condition- and good working order too. I think I have some resistance wire somewhere that might be suitable for the job. Does it have to be exactly the same spec as the original?

Posted by Vic Newey (Member # 5181) on January 01, 2016, 08:54 AM:

Thanks for the reply Terry,

I would think the wire has to be very similar guage, I carefully rewound mine with some heavier guge wire that I had in the shed & although it runs o.k the speed won't alter & stays constant, I've ordered a spool of resistance wire off Ebay, I found a mention of the correct guage on this forum & the wire on order is about right so I will post an update when it arrives.

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