Calculating timing belt lengths

[Jonathan]

Here's a spreadsheet to help when working out timing belt lengths. There are plenty of these calculators online, but I made this as I find it makes it easier to compare options when you can list them.
I've put 5mm in the belt pitch to use it with 5M HTD pulleys, which are often recommended here for driving ballscrews, but if you want to use it for a different belt series just enter the pitch. So for instance to use it with XL timing belts, put 5.08mm.

Attachment 8374

As for buying the belts and pulleys, Bearing Station tend to be the cheapest, but sometimes a bit slow to deliver. There's also Belting online who offer a service to bore and tap the pulleys, however they are more expensive.