Is this normal? - RC-Monster Forums

George16 · **Is this normal? -** 02.25.2009, 05:31 AM

I just finished installing my Castle 2200Kv motor on my ST RR and noticed that the motor shaft have about a 2-3mm fore/aft play. I didn't notice this much play on my TeknoRC Neu and Medusa motors.

Here's a vid:

JERRY2KONE · **Depends -** 02.25.2009, 07:08 AM

Most of the motors that I have seen in teh commercial industry are manufactured to some pretty stricked tollerances, but I have noticed that a lot of the R/C motors seem to have a lot more end to end thrust movement than I am used to. It does seem a bit odd though. For companies making such high end motors for racing and whatnot you would think that the tollerances would be a little bit tighter.

phatmonk · 02.25.2009, 07:44 AM

I noticed the exact same thing about the CC 2200.Cant you add shims?I remember seeing a diassembled Neu 1515 and it appeared to have shims on the pinion side of the stator shaft.

plettenbergs · 02.25.2009, 07:57 AM

i just checked my motors and none of them are like that!! looks like a bearing problem is arround the corner??

George16 · 02.25.2009, 08:00 AM

I really don't want to open it up and install some shims. I posted it here for everyone (including Patrick and the Castle guys) to comment on it since they manufactured it. I do know that motor/pump shafts have tight tolerances like Jerry stated.

I'm going to run it as is and see what happens.

02.25.2009, 08:09 AM

I just checked my Castle 2200Kv motor and it has very little endplay.

I'd say less than 1mm, no where near the amount thats in the vid.

George16 · 02.25.2009, 08:20 AM

Hmmmm, this is not good then.

I was really surprised to be able to move it that much as shown on the video. I can accept 1mm of play but not greater than that.

JERRY2KONE · **Contact directly -** 02.25.2009, 09:22 AM

Quote:

Originally Posted by George16

Hmmmm, this is not good then.

I was really surprised to be able to move it that much as shown on the video. I can accept 1mm of play but not greater than that.

Why dont you just shoot Patrick a PM directly to share the info with him that way first, then come back and let us know what the scoop is?

RC-Monster Mike · 02.25.2009, 09:32 AM

That is excessive endplay for sure - almost as if it is missing a shim altogether.

George16 · 02.25.2009, 09:36 AM

Thanks Mike. I'll try to give them a call tomorrow morning after I get up from bed (0430 a.m.).

If they tell me to return the motor, it means I'll have to wait for at least a week again argh.

Pdelcast · 02.25.2009, 12:54 PM

George,

What I see there isn't unusual -- that's only about 1-2mm end play. Some older batches had even more play than that -- because we were allowing the rotor to self-locate during run for best efficiency. As we get our rotor manufacturing (and magnet location consistency) better, we are tightening the end-play up.

As the motor ages, the end-play will increase -- but as long as the end play is the rotor moving between the bearings, no problem. If you start to see the internals of the bearings moving (the race and balls getting worn, or the shields starting to wear and fail) then it is time to replace the bearings.

Patrick

phatmonk · 02.25.2009, 01:54 PM

Pdelcast could a shim be used to tighten up any play?Granted ofcourse a shim that allowed a little movement and no binding.

Pdelcast · 02.25.2009, 03:48 PM

Quote:

Originally Posted by phatmonk

Pdelcast could a shim be used to tighten up any play?Granted ofcourse a shim that allowed a little movement and no binding.

Any kind of shim on the shaft would have to be made of a material that won't gall -- something like brass.

I don't think the play will cause any issue, because under torque the rotor will always stay in the same position.

George16 · 02.25.2009, 04:34 PM

Thanks for the input Patrick. I'll run it as is when the weather clears up. I just hope it will not cause any issues as you stated. However, if it becomes an issue, I would expect you will warranty it.

JERRY2KONE · **Whats uuuuuuupppppp lito? -** 02.25.2009, 06:02 PM

Hey I just had a vision and was wondering if you had gotten permission to run any of your toys on the flight deck yet? The vision was you loosing control and watching your truck take off like one of the jets over the side. I can only imagine that having you driving one or your R/C's on the flight deck during an underway would be a cool way to stir up some new R/C enthusiasm. Who knows you might cause some more ADDICTIONS. Kind of funny when you think about what your new job is????