Portescap motors

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Lysander
Posts: 2135
Joined: Wed Aug 22, 2007 9:53 pm

Portescap motors

Postby Lysander » Sun May 26, 2019 8:17 pm

A quick word of advice about these excellent motors.

Usually extremely expensive, I recently purchased a 'new/old stock' RG4 for a Hall that I am currently building. At £35, it was at least half the usual price and I was pleased with the purchase. I took it out of its box to test it yesterday and found that the gear-box had seized completely. Dismantling the unit, I tested the motor, which worked perfectly: it would not drive the gear-box however.

I could see absolutely no flaw at all in the gear train. These units are lubricated for life and so should not fail. Applying a little oil, I added a half-wheeled axle to the final gear and turned the 'box over by hand: a phenomenal amount of torque was required to move the cogs at all.

A plea for help in the other place brought an immediate response. The problem was known, and it was caused by dried out lubrication which effectively binds the gears solid. Two hours in a bath of IPA [which turned the colour of dry sherry!] resolved the problem. A light oil and the gear-box, reunited with its motor, turned perfectly.

I've a number of these units and have not encountered this issue before. They are so well made and reliable, it never occurred to me that this could happen. If any of you use them too, its worth keeping this in mind.

Tony
Men with false teeth may yet speak the truth.......

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TheDuke71000
Posts: 148
Joined: Fri May 31, 2019 1:58 pm
Location: Mora La Nova, Spain

Re: Portescap motors

Postby TheDuke71000 » Fri Jun 14, 2019 4:38 am

Lysander wrote:A quick word of advice about these excellent motors.

Usually extremely expensive, I recently purchased a 'new/old stock' RG4 for a Hall that I am currently building. At £35, it was at least half the usual price and I was pleased with the purchase. I took it out of its box to test it yesterday and found that the gear-box had seized completely. Dismantling the unit, I tested the motor, which worked perfectly: it would not drive the gear-box however.

I could see absolutely no flaw at all in the gear train. These units are lubricated for life and so should not fail. Applying a little oil, I added a half-wheeled axle to the final gear and turned the 'box over by hand: a phenomenal amount of torque was required to move the cogs at all.

A plea for help in the other place brought an immediate response. The problem was known, and it was caused by dried out lubrication which effectively binds the gears solid. Two hours in a bath of IPA [which turned the colour of dry sherry!] resolved the problem. A light oil and the gear-box, reunited with its motor, turned perfectly.

I've a number of these units and have not encountered this issue before. They are so well made and reliable, it never occurred to me that this could happen. If any of you use them too, its worth keeping this in mind.

Tony


Tony et al,
There is another problem with all coreless motors, they do not like any type of power supply unless it is pure unadulterated DC. So Half Wave controllers are out. Feedback controllers are out. And if you are using DCC, and using poor quality chips which often provide half-wave, (because they use 4 diodes in a quadrant to splice AC in half, without any supression of the problem). Then you run the risk of blowing any coreless motors.

Note: The DJ models Southern Class 02 0-4-4T, I recently purchased, uses a small (mobile phone motor) which is coreless, and I already know of one of these being blown in seconds because a Hornby chip was stuffed in it !!!!!

I have a number of locos fitted with Coreless motors, (including Portescap) and some of them can be seen on my layout "Basingstoke 1958-67" (87ft x 23ft), in the Model Railway photography section. But then I learnt 30+ years ago about the problems of Coreless motors when I was helping out at Pendon. So I've always used good quality but straightforward controllers such as the Gaugemaster range (excluding their little handheld Feedback coontroller) to avoid nasty problems.

The Duke 71000



The Duke 71000


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