Joints for Delta Printer

From RepRap
Revision as of 09:39, 7 May 2014 by DavidCary (talk | contribs) (link to article that goes into more detail, etc.)
Jump to: navigation, search

Delta

Principle and Requirements

TBD

The precision of nozzle positioning depends on rod length and a correct nodal point.

Variants

Cardan Joint

TBD

DIY Cardan Joint

TBD

PROs:

  • Very low cost
  • TBD

CONs:

  • Precision depends on manufacturing and assembling. Little manufacturing and assembling error results in a much bigger nozzle positioning error
  • Needs more space in construction
  • TBD

Industrial Cardan Joint

Industrial Cardan

TBD

Main Problem: In only 4 directions the joint can be tilt up to 90°. In directions between the usable angle is limited to about 30° (depends on design).

PROs:

  • Ready to use
  • M4 or M5 mounting threads
  • Less friction
  • Threaded rods can be used in between


CONs:

  • Cost per joint about 12 Euro
  • Have to be constructed in 45° angle to minimize limits
  • Have to be mounted in optimal working direction

Rod End Bearing

Rod End Bearing

TBD

Main Problem: At rotation axis the joint is designed for endless rotation. But at the tilt axis the joint is limited by construction. As manufacturer documentation tilt is limited to ±30° (Source: igus.de). To use the maximum reaching area as printing area a tilt angle of 35…40° is necessary. In result you can use only a limited printing area.

PROs:

  • Ready to use components
  • Threaded rods can be used in between

CONs:

  • Limited printing area
  • Conical spacer required
  • TBD

Magnetic Joint

Magnetic Joint Example 1
main article: magnet joint

TBD

Note: V2A balls are not magnetic and can not be used!

PROs:

  • Precision by design
  • No backlash
  • Implicit correct and well known nodal point
  • Low cost. About 1 Euro per joint
  • Simple construction
  • Easy assembly
  • Easy disconnecting for service and transport

CONs:

  • Limited holding force
  • Magnets are sensitive to shock and high temperatures

Magnet in Tube Variant

Magnet in Tube Variant

TBD

PROs (additional):

  • TBD

CONs (additional):

  • Precision depends on tube cutting and deflashing
  • TBD

Moving Ring Magnet Variant

Moving Ring Magnet Variant

The bearing balls are glued to the lift and carriage. The ring magnets are part of the rods.

TBD

PROs (additional):

  • TBD

CONs (additional):

  • TBD

Fixed Ring Magnet Variant

Fixed Ring Magnet Variant

The ring magnets are pressed in and glued to the lift and carriage. The bearing balls are part of the rods.

TBD

PROs (additional):

  • Depending on design up to (and over) ±90° tilt angle

CONs (additional):

  • TBD