Archive for December 2nd, 2017

MPCNC: Belt Tensioners

The GT2 / GT3 beltĀ specs call for 10-ish pounds of tension, but I don’t yet have a good feel for the actual MPCNC belt tension … and it’s hard to measure in-situ. So I picked up some spring tensioners and yanked one with a luggage scale:

GT2 Belt Tensioner - 4 kg

GT2 Belt Tensioner – 4 kg

You’re looking at 4 kg = 8-ish pounds of tension. When they’re relaxed, the arms sit at roughly right angles.

I installed them on the far end of the belts, although that’s a bit snug under the roller:

GT2 Belt Tensioner - installed

GT2 Belt Tensioner – installed

An endstop switch will eventually add some clearance and it’ll be all good.

Even though they’re neither linear nor precisely calibrated, they’ll serve as a reminder to check the tension every now and again.

Install them with the same casual disregard you reserve for fish hooks and you’ll emerge unscathed.