Quote:
Originally Posted by BrendanB
This past year we used this calculator produced by 1640 to space our wheels apart using 35 chain. We CNCed our drive plates, assembled, and haven't touched the chain since. It has stretched a little over the course of a long season with 6 events but it still runs great. We had a plan for tensioning if needed using a round piece of delrin with an off center drilled hole for mounting so we could rotate the piece around until proper tension was re-achieved and tighten the mounting bolt.
However I would assume since your single chain run is nearly the entire length of the robot (assuming you direct drive the traction wheel) the chain slack would be more noticeable compared to teams running an 8wd with C-C around 8in as you have more links to stretch out. A bearing block system might be more appropriate but you can use the chain calculator to help in design so your bearing block starts where you need it and tension from there. |
For 1:1 ratios, the math becomes dead simple. For Chain, the c-c must be a multiple of the chain pitch (.25 for #25, .375 for #35). It can be a multiple of the half pitch if you're willing to use a half link.
For belt, it must be a multiple of the half pitch (BUT don't assume all belts are sold!). Required toothcount on the belt (B) is;
B = T + 2*C-C/P
T = Pulley toothcount
C-C = Center to center (in same units as P!!!)
P = Pitch (in same units as C-C).
For both chain and belt there are arguments for adding a fudge factor to the c-c. I generally don't for shorter distances, but will more commonly do so for longer distances (or for small pitch belts).