Upgrades to the KRMx02 CNC

Now that my KRMx02 is tuned up and making chips, I thought I'd start to document some of the upgrades I've made.

The image below shows the Z-Axis constant-force spring I installed. The Z-Axis assembly weighs a bit over 22 pounds, so to help equalize the forces on the lead screw I installed a 9 pound-force, 25,000 cycle constant-force spring that I got from McMaster-Carr. The front of the spring bracket will hold the vacuum hose, as well as the coolant and air lines for the mist coolant system I built for $20 (which I'll document some other time). In the photo, the vacuum hose is off to the side for clarity. I built the 'tower' from 3/4" x 1/8" angle stock I had handy, plus a bracket for the spring end from 1-1/4" x 1/16" stock. The angle stock wraps around the extended Z carriage for good stability. There is some adhesive felt on the Z extrusion to prevent the spring from rubbing the aluminum - it s black and just barely visible. Also note how the router power cord is routed.

The result is that the Z-Axis is more difficult to push down by hand (power off) and the motor noise is more symmetrical up and down.

PM me with any questions.

http://i42.tinypic.com/2ed4ggk.jpg

very cool upgrade. :)

Might want to check out the SuperPID upgrade. Instructions for the upgrade can be found here:
SuperPID Upgrade — Kronos Robotics

An air diverter, dust shield and vacuum connection are nothing new, but I couldn't bring myself to pay for one...so I developed my own.
This design can be modified for virtually any router, any vacuum hose size, and almost any CNC router.

Important to this design is to use Polycarbonate (Lexan, Macrolon) and not acrylic. Acrylic shatters and I consider it dangerous as glass.

Below is the top plate of my dust shield and air diverter (white protective film still attached; it uses clear plastic), and a photo of an older version fully assembled (uses a different router attachment). The Polycarbonate bends like aluminum, so those tabs you can see on the plate are what I use to attach to the router body along with a 4" hose clamp. The bottom plate looks similar, but the router opening is simply a 1.5" hole, big enough to let the collet poke thru. I use machine screws and 1/2" diameter Lexan tubing to space the plates apart. Cost is just a few dollars. Note that one machine screw on the right is missing: You need space to get the colletwrench in there and turn it. http://i57.tinypic.com/2442txl.jpg
http://i62.tinypic.com/2ibkahg.jpg[/quote]

What sheet thickness of Lexan did you use?

Thanks.

I have redesigned the AirExchanger so that you can make them yourself.
https://www.kronosrobotics.com/airexchanger

Re-attaching photos.
Z-spring:
Attachment 433524
Air Diverter: This is 2 plates of polycarb - top is 3/32 or 1/8, bottom is 1/16. Joined by bolts through polycarb tube, about 1" long. Bottom has door-sweep brush attached. Top has a white LED ring attached around the router spindle hole.
Attachment 433528