Bearing

From RepRap
Revision as of 21:24, 29 May 2013 by Virtlink (talk | contribs) (Moved linear bearing info to its own page (will move ball bearings shortly))
Jump to: navigation, search
Bearing

Vitamin

No image available.png
Lineair and ball bearings.
Wikipedia Bearing

A bearing ensures two parts can slide or roll along eachother with minimal friction.

Ball Bearings

Cheap and widely available

The first digit refer to the kind of bearing, the second its robustness, the third usually for the bore size. Then ZZ = double shielded ; 2RS = double sealed ; etc.

If we were generating a lot of dust and grit -- perhaps with a Milling and Drilling Head -- we would want two rubber seals ("2RS") to keep the dust and grit out. But most RepRaps are *not* generating a lot of dust and grit, so we usually prefer metal shields ("ZZ") or unshielded (??) in order to make it easier to add a little lubrication oil.

Learn more here : http://www.gizmology.net/bearings.htm

For the most common size :

  • 623 = 3 x 10 x 4mm (ID-OD-thick)
  • 624 = 4 x 13 x 5mm
  • 626 = 6 x 19 x 6mm
  • 608 = 8 x 22 x 7mm
Supplier From Model Approximate Cost Additional notes
Charlie's 3D Technologies Belgium 608zz 0,61 € -
Paoparts France 623zz, 624zz, 626zz, 608zz 0,69 - 1,20 € -
Reprapsource Germany 624zz, 608zz 0,69 - 0,79 € -
Reprapkit UK 624zz, 608zz, 6810zz 0,85 - 0,95 £ -
3D Maker World US 608zz $0.75 ea -
Bocabearings US many - -
VXB US many - -
DDB-Tech China many - -
Technobots Uk many - -
CIE Auto Source China many - -
wholesale skateboard US 608ss $ 0.38-0.50 ea minimum 80 pcs
imprimante3DFrance France 608ZZ, 623ZZ, 624ZZ, 626ZZ - Paris area

The "608" size ball bearings in particular are extremely low cost. Their 8 mm bore size almost forces us to mount them on:

The "626" size ball bearing have a 6 mm bore size. We can mount them on

The "624" bearing have a 4 mm bore size. We can mount them on

(The 626 and 624 bearings seem to cost more than 608 bearings, but M6 and M4 bolts and threaded bar cost less than M8 threaded bar and bolts, so it's almost a wash).

Linear Ball Bearings

See: Linear bearing

Bushing

Less noisy than linear ball bearing but not always practical to integrate

DIY PLA bushings

DIY UHMWPE linear bearings (ultra high molecular weight polyethylene) are self-lubricating, so rails can stay clean and dry.

Supplier From Size Material Approximate Cost Additional notes
Goldmine US 8 mm bronze 1 $ don't use on 5/16" rod
iglidur D6 Paoparts France 6 mm plastic 1,20 € -
iglidur D8 Paoparts France 8 x 9 x 12 mm plastic 1,50 € -
Everything Igus multiple - - -
Sdp-Si US 8 mm plastic 1,80 $ self-aligning
Spyraflow US 8 mm bronze  ? self-aligning
Techpaladin US 8 mm bronze 1,70 $ self-aligning

Linear Rail

  • Igus
  • schneeberger.com
  • pbclinear.com (also for many linear bearings)
  • Hiwin (look on ebay)