28-01-2013 01:39

DampRobot

Re: pic: MiniCIM Versaplanetary

So, essentially, the Mini-CIM mounts to the holes that hold the gearbox together? Also, how do you mount the CIM shaft to the pinion? I didn't know that there was a 8mm pinion available for those gearboxes.

28-01-2013 01:41

AllenGregoryIV

Re: pic: MiniCIM Versaplanetary

Check out the blog post for the full instructions. You don't use the holes that hold the gearbox together you use the other two holes. There isn't a pinion at all, the gearbox accepts an 8mm shaft and key.

28-01-2013 09:38

Kellen Hill

Re: pic: MiniCIM Versaplanetary

Are you planning to use these on your drivetrain?

If so, what reduction are you using in the gearbox?

28-01-2013 11:13

Chris is me

Re: pic: MiniCIM Versaplanetary

I really wish you had posted this two weeks ago. At one point I designed a mechanism that fed a mini-CIM through a VP and we had to redesign everything once we realized it wasn't a stock fit. I guess we should have been more creative.

Novel design nonetheless!

28-01-2013 11:36

AllenGregoryIV

Re: pic: MiniCIM Versaplanetary

No, we wouldn't risk that. We have a use for one right now and it will probably see the actual robot but it won't be on the drive train. With 6 regular CIMS allowed there is no need (unless you have a serious power need for a climbing device) to use anything but large CIMs on your drive train.

I wish we had known as well, we didn't find it until JVN hinted at the possibility. I still can't believe VEX designed all of these features into the gearboxes and never talked about it.

28-01-2013 11:46

Kellen Hill

Re: pic: MiniCIM Versaplanetary

I was thinking of putting the large CIM into the planetary. Should mount the same as a mini CIM unless I'm mistaken.

We currently have a couple old Banebot planetaries and are looking to switch them out.

28-01-2013 11:52

AllenGregoryIV

Re: pic: MiniCIM Versaplanetary

Oh, yes the input would be the same but again this current setup has very little keyway profile so for heavy torque applications it might not be the best design. (This is just from FRC experience I'm not a Mechanical Engineer.)

We are using the VEXpro single speed gearboxes but I would think the VPs could work in place of the large BB gearboxes. Check the torque ratings table on the VEXpro website for guidance though non of those are for this setup as it isn't officially recommended by VEX.

The single speed gearboxes we are using are 5.33:1 so a 5:1 VP would be a suitable replacement.

28-01-2013 15:02

ken.3038

Re: pic: MiniCIM Versaplanetary

Our team is going with a single wheel (8" pneumatic) with a curve. The first attempt was a CIM direct to a hub mounted on the wheel but failed. The hub egg shaped from the CIM shaft. Next we tried a belt driven shaft mounted with bearings but there is to much vibration. We have ordered 2 Versaplanetary gearboxes which one will be changed to 1:1. Mounted to a AndyMark 1/2" hex hub. The idea came from your thread with your small shooter. I shouldn't have cut the shaft with a 1:1 correct?

28-01-2013 15:41

AllenGregoryIV

Re: pic: MiniCIM Versaplanetary

If you are mounting a CIM to the VP you will have to cut the shaft no matter what gear ratio. The shaft can't go all the way through the input stage, unless you did some really interesting modifications. You could use standoffs and cut the shaft less than we did.

28-01-2013 16:29

billbo911

Re: pic: MiniCIM Versaplanetary

I believe a solid machined block might give a more secure interface than standoffs.
As you suggested, this would give both the Mini CIM and CIM the ability to interface to the VP without modification.

Are you catching this John? It would make an already great transmission even better.

28-01-2013 17:47

AllenGregoryIV

Re: pic: MiniCIM Versaplanetary

I agree with the secure interface idea. However I'm not sure you can do it without modification because the keyway on the 8mm shaft of the CIM and MiniCIM doesn't extend to the end of the shaft.

04-02-2014 01:09

DampRobot

Re: pic: MiniCIM Versaplanetary

I've seen VersaPlaetaries configured like this on Build Blitz, but I couldn't find any more info on how to use the VersaPlanetaries in this way with the new version. I assume others have done this successfully since then. How did you do it with the new version? Specifically, what plates did you use, did you cut off the CIM shaft, and did you still have to use 8-32 screws in place of the 10-32s in the CIM?

04-02-2014 01:12

R.C.

Re: pic: MiniCIM Versaplanetary

We are using MiniCIMs in Vp's. What we are doing is cutting the shaft. Drilling out the CIM mounting holes to #10 (the input housing only) and then turning down socket bolt heads to fit nicely, works well.

04-02-2014 01:15

DampRobot

Re: pic: MiniCIM Versaplanetary

Do you use any of the plastic/aluminuim plates or no?

04-02-2014 01:16

AllenGregoryIV

Re: pic: MiniCIM Versaplanetary

We're still cutting the shaft & still using 8-32 bolts, and still haven't had one fail yet. We do use the aluminum plate since it pilots the CIM. We had one on our lift (not for climbing but for defense) and one on our shooter last year and never replaced either one. I still don't think the #8 bolts should work but they do, and the best part is you don't have to modify your versaplanetary at all.

04-02-2014 01:16

R.C.

Re: pic: MiniCIM Versaplanetary

We use the plastic plates, drill the 775 guy out to 3/4. Our thought was that if we are going to replace a MiniCIM on this years robot its going to be for weight (BAG!). So we kept the BAG plates unmodified and the drilled out the 775 ones.