Motor advice

[quazz19]

Hi ya, 

 

I have a set of shs 12:1 gears in a Vfc gearbox, completely standard otherwise.

 

I’ve bought a zci 22tpa 18k high torque motor i want to fit. 
 

at what stage do I need to worry about PME? I use a 9.9v life and a m100 spring.

 

so my question is will the set up be ok or do I need to short stroke? 
 

thanks in advance for any advice. 

[matas17]

8 minutes ago, quazz19 said:

Hi ya, 

 

I have a set of shs 12:1 gears in a Vfc gearbox, completely standard otherwise.

 

I’ve bought a zci 22tpa 18k high torque motor i want to fit. 
 

at what stage do I need to worry about PME? I use a 9.9v life and a m100 spring.

 

so my question is will the set up be ok or do I need to short stroke? 
 

thanks in advance for any advice. 

When I personally build gearboxes for myself I rarely short stroke anymore and leave gears alone, just have it well shimmed, aoe sorted and rof turned up or turned down on gate titan software. In rare occasion when i want to see how fast of and ROF I can reach that I short stroke gears. At the moment my vfc mcx gearbox is short stroked by 2 teeth on 13:1 gears and i get around 35rps. 

Edited February 24, 2024 by matas17

[Pseudotectonic]

(Just my rule of thumb) anything above 28 RPS is at risk of PME so will need short stroking

 

You can calculate your paper ROF and see if it is over 28

 

e.g. say the 22 TPA is 25000 RPM, at 9.9 V this is 25000 x 9.9/11.1 = ~22300k

 

22300 / 60 / 18 = ~21 RPS so should be very safe in terms of PME

 

This did not take into account efficiency loss which will make the number smaller

[Leo Greer]

You should be okay. My calcs put you at approximately 26 RPS with 9.9v and 12:1, and at that point it’s down to individual build. I put together a 1J setup that did 30 RPS and it was fine, but I’ve also had troubles at 28 with another build.

[Sewdhull]

Ignore 

Edited February 25, 2024 by Sewdhull