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Bearings, rails and mechanical hardware

Bearings, linear rails, couplings, gears, pulleys, aluminum extrusion and fasteners for machines, printers and robots.

116 results

About bearings, rails and mechanical hardware

The mechanical side of a build: the parts that hold it together and let it move. Bearings include 608, 695 and F623 ball bearings, thin-wall and thrust bearings, pillow blocks and LM8UU linear bearings, alongside hardened linear shafts, MGN miniature linear rails, ball screw kits and anti-backlash lead screw nuts. Motion passes through flexible jaw and clamping shaft couplings, spur and bevel gears, gear racks, and GT2 and HTD timing pulleys and belts.

For frames there's 2020 V-slot aluminum extrusion with corner brackets, T-nuts, gantry plates and V-wheels, plus M3 screw kits, brass standoffs and heat-set inserts. Stepper mounts and vibration dampers, cable drag chains, lever and push-in wire connectors, screw terminal blocks, ferrite magnets and enamelled magnet wire round it out. Check bore and shaft sizes in millimetres, and the extrusion's slot size, before you order.

116 listings today, from $2.36; half cost $11.03 or less.

What to look for

Start from the motion. Ball bearings carry rotating shafts, linear bearings and miniature rails carry sliding carriages, and a lead screw or ball screw turns a motor's rotation into straight-line travel. For frames, 2020 V-slot extrusion with corner brackets and T-nuts is quick to build and easy to change later.

Specs that matter

Bearings are sized by bore, outside diameter and width in millimetres: a 608 bearing is 8 x 22 x 7 mm. A shaft coupling needs one bore for each shaft, and a pulley needs the belt's tooth profile (GT2 or HTD), a tooth count and a bore. Check screw threads and lengths against the extrusion or part they go into.

Compatibility tips

Match T-nuts to the extrusion's slot profile as well as its size. A NEMA 17 motor has a 5 mm shaft and a T8 lead screw is 8 mm, so the pair needs a 5 x 8 mm coupling. For household wiring, use connectors certified for that use and follow your local electrical code.

Questions about bearings, rails and mechanical hardware

What do bearing numbers like 608ZZ and 608RS mean?
The number gives the size: a 608 bearing has an 8 mm bore and a 22 mm outside diameter, and it's 7 mm wide. ZZ means metal shields on both sides; RS or 2RS means rubber seals, which keep dirt out better but add a little friction.
Which T-nuts fit 2020 extrusion?
2020 extrusion is 20 x 20 mm with a 6 mm slot, and most frames built from it use M5 T-nuts and screws. Match the T-nut to the slot profile (V-slot or T-slot) as well as to the thread you need.
How do I join a motor shaft to a lead screw?
Use a shaft coupling with one bore for each shaft, for example 5 x 8 mm for a NEMA 17 motor driving a T8 lead screw. Flexible jaw couplings absorb small misalignments; rigid clamping couplers hold the shafts exactly in line.
How long does delivery take, and what does shipping cost?
Most parts ship to Canadian addresses directly from our supplier partners, most of them outside Canada, and most orders arrive within 1 to 3 weeks; the product page shows its own estimate. Items marked eligible on their product page ship free once the eligible items in your cart total $20 or more (a cart of many low-priced parts needs more than $20 of them, and the cart shows how much). Until then, and for items that aren't eligible, each item pays its supplier's shipping quote for your address, and checkout shows every charge and the tax before you pay.

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