AM FP Planetary Gearbox with CIM

[Sh1ine]

Can anyone fill in the blanks as to how you mount a CIM onto the AM FP Planetary gearbox? After you bore our the sun gear how do you prevent the CIM shaft from slipping? Thanks.

[Wayne TenBrink]

Are you trying to put a CIM on an AM-0002?? That item supposed to make an FP emulate a CIM. There are other planetary gearboxes intended specifically for CIM's.

Regardless, I believe that you would need to broach a .125 keyway in the enlarged bore of the sun gear (if there is room) to keep it from slipping on the CIM output shaft.

[Tristan Lall]

Originally Posted by Wayne TenBrink

Are you trying to put a CIM on an AM-0002?? That item supposed to make an FP emulate a CIM. There are other planetary gearboxes intended specifically for CIM's.

Regardless, I believe that you would need to broach a .125 keyway in the enlarged bore of the sun gear (if there is room) to keep it from slipping on the CIM output shaft.

Isn't that a 2 mm keyway on an 8 mm shaft?

The AndyMark planetaries intended for CIMs are the GEM series.

[ADZDEBLICK]

we bored out the gear and pressed it onto the cim shaft (no key, pin, set screw). Haven't had any problems yet.

[IndySam]

There are many teams who mount CIM's on AM Planetary's. You do need to purchase the correct spacer and gear from AndyMark but it looks like the spacer is out of stock.

[ADZDEBLICK]

If i recall correctly, all we had to do was flip over the planetary cap, mount the cim to it, and trim down the cim shaft after the gear was on.

[JesseK]

Can the AM planetary handle the torque output of a CIM under load? I would presume that using this setup in a drive or winch may be attractive due to weight, but I worry about the longevity of the tranmission.

[Cory]

Originally Posted by Chris is me

Broaching a keyway is probably the easiest way to make it work at this point if there's room. 2mm keyway, 8mm shaft because CIM shafts are metric..

You can't broach the pinion. There's already only like .030 of wall thickness between the root of the tooth and the bore for a press fit.

[Sh1ine]

Will a press fit work?

[ADZDEBLICK]

we haven't noticed any issues with our press fit. Your other option is edm the gear so it has a built in key or DD.

[AdamHeard]

It's doable, and not that hard of a process. This post describes what we did; you could easily do it without motor dis assembly to cut the shaft short.

Originally Posted by Chris is me

Are you sure the CIM needs the extra reduction to work? I thought the early math showed the gearbox juuuust worked without it, but I'll bite. There used to be instructions on the AM site.

This is definitely possible, my old team's done the mod. It's a nice way to add a little more reduction to a CIM based power system without needing to change things up too much, which is exactly what the team needs. This has absolutely been done before more than once, AndyMark's website claims you can, etc. etc.

Broaching a keyway is probably the easiest way to make it work at this point if there's room. 2mm keyway, 8mm shaft because CIM shafts are metric. I don't know if that can be done. AndyMark sells a 15 / 32 gear that interfaces with the CIM that will work if the broach doesn't. After the gear's all set and the spacer fits right (which has to be made since AM doesn't appear to have it in stock), trimming the end of the motor shaft is all that should be needed.

I don't remember every step of the process in detail, so if there's more trouble I'll bounce an email down.

Not to pick on you specifically, just an example.

I've seen many, many people speculate on processes they do not know and are making pretty wild guesses. Broaching a keyway in this would simply not work.

If you post a technical answer on chief, you better be sure it's valid. People will read your post, and many will take it as fact and not know better.

[Cory]

Originally Posted by ADZDEBLICK

we haven't noticed any issues with our press fit. Your other option is edm the gear so it has a built in key or DD.

There is no way to put any sort of keyway into the pinion. It does not matter how you put it in-there simply is no material with which to do it.

[sanddrag]

I'm curious if Loctite 680 would hold. I've played with it before, holding a gear on a shaft, and it took some rather large channel lock pliers on the gear, with the shaft in a vise, , to get it to slip on the shaft.

[Andy Baker]

This is one of those cases where I put something up on the AndyMark site to make it available, and forget about it until people start asking questions. Sorry about this lack of communication.

1. The CIM Sun Gear is available. The bore is sized to be a press fit onto the shaft of the CIM Motor. No fasteners are needed. Loctite will help secure this to the shaft, but it is not required.

A press fit in this situation is acceptable, as this is a high rpm, low torque location.

2. We don't have the CIM Spacer finished yet (our mills have been very busy with higher priority things). The intent of this part is to space the CIM Motor away from the AM Planetary gearbox so that the CIM Motor shaft does not have to be cut off. If you don't mind cutting off the CIM Motor shaft, then no spacer is needed.

3. The cap of the AM Planetary will need to be turned over during assembly in order to make this work. You must attach the cap to the gearbox, and then attach the CIM Motor to the cap. No alteration to the cap is needed in order to make this work.

Essentially, while using this CIM Sun Gear, the only thing you have to do to add a CIM Motor to the AM Planetary is slice off the CIM Motor shaft after the gear is pressed on.

Let me know if you have any further questions.

Sincerely,
Andy

[Ether]

Originally Posted by AdamHeard

It's doable, and not that hard of a process. This post describes what we did; you could easily do it without motor dis assembly

Are you recommending that the pinion be pressed onto the motor shaft while the shaft is still in the motor? I wonder if the motor bearings are designed to withstand such an axial load without sustaining damage... especially since small machining tolerances for the press fit can result in large variations in required press force.

If the shaft is not removed from the motor, a shrink fit might be a safer approach.


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