need help fast!!! Hubless 1/4 pitch sprockets

FIRST General Forum
1

Sorry for the cross post but i need this information fast!

I am currently trying to finalize a drivetrain design and print out some drawings and order parts first thing tomorrow morning

I need to know what is the largest 1/4 pitch sprocket available

and where can i find a place to get it to me as fast as possible (2 days or less)

i am hoping it is at least 72 teeth

ALSO… what is the least number of teeth when using 1/4 pitch chain to minimizing slipping and tooth breakage?

thanks alot

2

Small Parts has them, I don’t know how big you can get them. Call them tommorow, and ask them for the sprockets that go with the hub attatchment for the skyway wheels, tell them you’re with robotics they will know what you are talking about. You can have them shipped 2-day.

hub Part number- FIR-DC01

they talk about the hub in this post:

http://www.chiefdelphi.com/forums/showthread.php?s=&threadid=15646&highlight=hub+skyway+sprocket

There is a picture of it that Matt Reiland posted.

We just ordered some of the same sprockets

They aren’t normally in the small parts catalog, they are in Appendix D

3

I am almost 100% sure small parts stops at 60 teeth they have nothing larger than that

But i do know martin sprocket makes them (or i think they do, they list up to 72 teeth but they seem to have a hub)

i do not know of a distributor though

keep the responses comin!

thanks

4

If you could find a hubbed sprocket the right size you could always take off the hub on a lathe. McMaster doesn’t have what you need. Maybe check MSC or Stock Drive Products.

<edit> you can get a 72 tooth hubless gokart sprocket but it’s for #35 chain. </edit>

<edit2>I found a 70 tooth 1/4 pitch hubless sprocket here It could be a metric pitch so call and check but it looks like 1/4 pitch to me. I believe it is a half inch bore. I thought of it when I remembered my electric scooter sitting right behind me so I counted up the teeth and there you go. Not exactly 72 but heck you can get it and it’s cheap. I’m not sure about the shipping. The company is in Orange County CA and you can actually go to them if you are persistent on the phone.</edit>

5

MSC didnt have em…

Stock Drive Products DOES!!!

Great

Motion Indistries probably has them as well and they are just a few mins away. i think i am set…

just for future reference SDP has them up to 125 teeth hubless 1/4 pitch

thanks for the quick replies!!

6

SDP/SI has up to 125 tooth 1/4" sprockets.

7

McMaster Carr has them. BBC Industries is being nice enough to give us our drive train(sprockets, pillow blocks, chainm clutch) . . . we have a coupla 80 toothers in there. They were going to give us a 120 or there abouts toother, but the diameter was such that It would take over our wheels job of touching the floor. not good.

Anyway, McMaster Carr also has these great sprocket hubs with an adjustable clutch. . . we are using the to prevent our CIMs from drawing more than 40A . . so we don’t have any down time from the breakers. They are fully adjustable, so we just put em through their motions till we get them just right.

By the way, I have no idea how to spell McMaster Carr, so don’t jump on me for it . . I may be right, I may be wrong . . and you guys know who I’m talking about. At least, I’ve seen them talked about before on these forums.