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View Full Version : Anyone willing to help?

Mschmeh144
22-04-2015, 10:15
Hello all
As we found out today, after attempting to finish this off season project tote bot, we don't have the matching size sprockets for our chain drive. At this point, it doesn't matter what size the chain is, there's nothing we can make work. Our final option is to go ahead and rip out drive trains from old robots
So, is there any other option before we have to rip them out?
ToddF
22-04-2015, 10:51
Are you trying to get something built for the Championship? If not, just order more sprockets. If so, come by our pit (Archimedes). We bring all our sprockets as spares and to lend out.
Qbot2640
22-04-2015, 11:56
Hello all
As we found out today, after attempting to finish this off season project tote bot, we don't have the matching size sprockets for our chain drive. At this point, it doesn't matter what size the chain is, there's nothing we can make work. Our final option is to go ahead and rip out drive trains from old robots
So, is there any other option before we have to rip them out?

I'm assuming from your statement that this is an off season project, that you have some time. Please describe what you are trying to do. We commonly use #35 chain in our mechanisms and would be happy to help...plus, there are sprockets, hubs, and chain that can be obtained rather affordably from AndyMark and Vex. If, on the other hand the old robots are non-operational...then stripping them down can be a great way to get new members started with the whole "build experience".
Mschmeh144
22-04-2015, 13:48
Yes, this is a off season project. The only time constraint is to have the bot at least working or almost 100% by the time championships is over.
Qbot2640
22-04-2015, 14:45
The linked table:
Roller Chain Dimensions (http://www.gmtel.net/web/drittmer/Technical/mechanical/Roller%20Chains.pdf)

will tell you what chain you have - sprockets should be stamped. #25 and #35 are the two sizes I've commonly seen in FRC - but I'm sure there are exceptions.
tr6scott
22-04-2015, 16:07
Checkout AndyMark booth, they can be amazing at champs, with free stuff to GP teams.

Thanks Andy!
Mschmeh144
23-04-2015, 09:36
Update, we found that when we tested the chain system, the frame was unable to hold,so we are rebuilding the entire frame from scratch, basically, starting over. The chain we used was not the chain we thought it was, assumed it was 25, it turned out to be 35. We have all the parts for the 35 chain. Sadly this is a major setback in this project, but thanks for the offers to help :).
GeeTwo
24-04-2015, 22:48
If you can't find any numbers on the chain, measure the chain pitch (distance between centers of rotation at the ends of a link). This distance, in eighths of an inch, will give you the "tens place" of the chain size. #25 is 1/4 inch, #35 is 3/8 inch. The ones place signifies details in constructin (width and bushing vs roller chain).