V1E LowRider 3 Pen / Drag knife / Drag Bit (RDZ Engraver) mount and adaptor

2023/12/14 UPDATE:
- Created more accurate XY constrained v2 mount.  
- Modified to have more vertical spring/flex while making more rigid in XY by encasing the spring section.
- Printed with PETG.
- Requires printer to have decent bridging settings. 
- Needed some cleanup and manually forced motion to free up, and wear in, the print in place spring.

2023/3 ORIGINAL:

• Recommend PETG for lr3-aza-pen-mount, will help with flex.
• Used PLA for lr3-aza-drag-bit-adaptor, but PETG would be fine too.

Created while trying to etch Specular Holograms, which require very shallow scratches.  Was initially using a diamond drag bit in the router, but that puts too much pressure onto the stock, and ends up engraving/gouging too deep.  So…

Looked around for existing mounts but couldn't find one that supports reusable zip ties.  Also, other mounts I stumbled onto were too high for the drag bit being used.  Am looking for something rigid in XY, but has some flex in Z axis, want to make light contact.

Latest details and discussion on V1E forum https://forum.v1e.com/t/lr3-mod-pen-drag-bit-knife-mount-and-adaptor/37182 

Design goals/features:

• Holes for reusable zip ties.  Made tight enough to hold zip ties when not in use.  No need to burn time finding some.
• Included 18mm dia, 3mm height cutout for drag knifes from V1E Shop (testing pending…)
• Mount attaches to my Makita router in specific location that:
  • 1) Doesn't block visibility of the bit where a gap in the dust shoes exists. 
  • 2) Doesn't block access to changing router bit (verify…)
• Mount shape design leverages and hugs features on the LR3 Router mount, this helps increase rigidity.  Design enables just one ziptie needed to fasten mount to the router.
• 3.3mm Diameter hole on the adapter enables push to release/remove bit.  Alternatively can use to mount something with M3 bolt.

Included .3mf with parts oriented ready for printing without support.  Print depends on small bridging and couple of small 60deg overhangs.
 

Future Improvements: (please ping if you remix and make better, cheers!)

• Could be stiffer in XY.
• Lost Z step ~25mins into an engraving session, scratches were noticeably lighter.  So, could probably be stiffer and/or less play with higher tolerances.  Not sure, mentioning as something to look out for.

Related work:

• V1E's https://www.printables.com/model/237997-basic-lr3-pen-mount
• Doug's https://www.printables.com/model/225516-lowrider-3-cnc-add-on-pen-holder-drag-knife-holder  
• Dan's https://www.printables.com/model/388240-low-rider-3-pen-drag-knife-mount 
   

Cheers!

See main description for differences.