we here at team 253 are trying to figure out how to attach an 8 inch andymark pneumatic tire (am-0970) to a CIM. How would we go about doing this? Preferably in laymen’s terms. Sorry about technical ignorance, we’re a fairly inexperienced team and we lack significant mentorship.
One of the more common methods is to purchase Hub that slides over the CIM output shaft, with a key, and bolts to the wheel just like a sprocket or pulley would. However you will need to retain the wheel somehow, and make sure you balance it or it might “death wobble.”
You could mount the wheel to an 8mm key hub from andymark. Then put the hub on the output of the cim motor. Then put an 8 mm retaining ring clip (andymark) on the cim shaft. That will connect them
Try this hub…
URL=http://www.andymark.com/product-p/am-0320.htm
or the 1::2 or 1::6 Spin Box gearbox.
I have found the wobble may be overcome by carefully centering the hub on the wheel.
Have fun!
Remember that the CIM will get very unhappy if the other end of a wheel shaft is not held with a bearing. So on the other side of the wheel from the CIM, make sure you mount a bearing there.
To save you some time our team tried the AndyMark Hub but the wobble factor egg shaped the hole on the hub. Then we tried to reuse the hub by drilling it out to 3/8" and rigged up a belt drive with a 1:1 ratio. That to failed mostly due poor drilling and not enough support. We now are waiting for this http://www.vexrobotics.com/vexpro/gearboxes/versaplanetary.html which can be changed to 1:1. Using a hex hub and locking collars from AndyMark. We are also an inexperienced team and got the idea from another post hoping this will work for us.
Although not as simple as using an Andymark hub (which is probably your best option) you can try mounting the CIM to a VersaPlanetary. Our team did that (to attach to another kind of wheel) and it works great. 3847 gave some basic instructions here.
I would advise milling a .50 inch spacer block (in place of the motor mounting plate) and then cutting the motor shaft to the proper length. This is will give you more shaft and prevent you from having to cut the keyway back farther than it was originally.
A couple other AndyMark products worth mentioning in this thread:
Not an all-in-one solution, but it may be useful to many teams contemplating how to attach their CIMs to their shooter wheels.
Here’s how we did it. 8mm retaining clip from Andymark on CIM, 8mm hub as others have recommended. We fabricated our motor mount locally. Hope this helps a little!
Team 3355
Pic 1:
http://i4.photobucket.com/albums/y120/pilum40/th_pic2-2.jpg](http://s4.photobucket.com/albums/y120/pilum40/?action=view¤t=pic2-2.jpg)
Pic 2:
http://i4.photobucket.com/albums/y120/pilum40/th_pic1-1.jpg](http://s4.photobucket.com/albums/y120/pilum40/?action=view¤t=pic1-1.jpg)
Pic 3:
http://i4.photobucket.com/albums/y120/pilum40/th_Arlington-20130131-00873-1.jpg](http://s4.photobucket.com/albums/y120/pilum40/?action=view¤t=Arlington-20130131-00873-1.jpg)
We turned a 4-5" piece of 1/2" hex aluminum down to 3/8 or 7/16 but left a taper at the shoulder and threaded to accept a hex nut. We then drilled out the end to match the CIM shaft. Using a 3/32 slit saw in a vertical mill, we machined 4 slots to make a collet. The hex shaft fits a hub as shown. It works well and hasn’t slipped so far… In assembly it will have loctite. A bearing captures the other end of the shaft.
http://www.chiefdelphi.com/forums/attachment.php?attachmentid=13736&stc=1&d=1359673416
