DIY Laser/XY Gantry
RussleH and 'RepRap' Matt (talk) took a look at the work is of the IMP Pick and Place at Ciseco
Pictures here
https://www.dropbox.com/sh/bhjxykpmvo0xxca/QPXxOIEow-/IMP
Locking a magnetic tape linear encoders, simlar to used on the PnP
This can give very high accuracy position feed back and at high speed
http://www.machine-dro.co.uk/digital-readout-systems/magnetic-tape-linear-encoders.html?p=1
Possible driver systems
- Fixed motor and looped belt to carriage
- Carriage mounted motor and fixed belt
- fixed motor driving a leadscrew
- fixed motor driving a ballscrew
Motors for each of the above could be one of the following
- DC motor
- stepper motor
- brushless servo motor
What speed do we need?
- for cut
- for none cut moves
- for etch/scan
Type of Gantry
There has been discussion over the XY gantry system.
There are two main ideas:
- Use a belt drive
- Use ball screws
Most lower cost laser cutters use belt drives.
Most larger machines use ball screws.
Here are notes on the two ideas:
Belt Drive
Belt Drive costs
Ball Screws
More information on ball screws can be found here: http://www.cnczone.com/forums/linear_rotary_motion/8813-ballscrew_basics.html
http://www.nskamericas.com/cps/rde/xbcr/na_en/Ball_Screw_Tutorial.pdf
Ball Screw costs
How accurate do we need?