I’ve made some good progress with the DIY Router project this last weekend.  In my last update on May 4, 2011 you could see that I was working on getting the uprights mounted.

Since then I’ve drilled and mounted the plates to hold the Y-axis cross beams (seen in the photos as the black plates left and right of the X axis) The plates are Blanchard ground aluminum which I took off some old linear assemblies, good flat metal, cheap but it does have some extra holes in it.  The 6 bolts are just 3/8″ galvanized carriage bolts, they fit in the Bosch/Rexroth extrusion’s T-slots and provide locking action when tightening down the bolts. These will probably be replaced with stainless hardware at some point.  The 4 stainless bolts in the front secure the Y-axis extrusions along with the corner brackets in the back (not installed in this photo).

I’ve also drilled and tapped the steel backing plates for the Y-axis linear rails which slip into the T-Slot of the Bosch Rexroth extrusion and then have the NSK linear rails bolted to them.  The rails mounted up pretty easy and were easy to align.

Additionally I purchased an 8 inch x 8 inch plate of mill finished aluminum and an 8 inch x 8 inch plate of Blanchard ground aluminum. The mill finished will be used to mount the router to the the Z-axis linear unit, and the Blanchard ground plate will be to mate the NSK Y-axis linear rails to the Z-axis linear unit.

I purchased some linear drive components from a few places last week and have been busy installing those:

4 * Bearing blocks for Acme 1/2-10 Linear Screws from CNCRouterParts.com
4 * Thrust Roller Bearings for Acme 1/2-10 rod from CNCRouterParts.com
2 * 5 Start Acme 1/2-10 Anti-Backlash Acetyl (?) Lead Nuts from dumpstercnc.com
2 * 5 Start Acme 1/2-10 – > 1/4 Acetyl(?) Shaft Coupler from dumperstercnc.com
4 * 5 Start Acme 1/2-10 Acetyl Threaded Shaft Clamps from dumpstercnc.com

For the drives on the X and Y axis I am using a combination of a spiral cut 1/4″ to 1/4″ coupler to a piece of 1/4″ drill rod which connects to the 1/4″ to Acme 1/2-10 coupler which connects to the 5 start precision ground 1/2-10 linear rod I purchased from McMaster-Carr. After the 1/4″ drill rod to 1/2″ acme coupler is a thrust roller bearing, and axial bearing block, and another thrust roller bearing.

The free end of the Acme rod is free floating in one of the bearing blocks at the opposite end of the X-axis. I over-size the mounting holes in the large aluminum cross plate as well as the over-sized the hole for the Acme rod as well so so I could adjust the center position of the free floating rod by about a 1/4 inch in any direction.

I also mounted a cross brace between the bearing blocks to help keep things aligned all the way around.  The piece is a 0.75″  x 3″ 80/20 extrusion that I bought from 80/20 on eBay along with some aluminum bar stock and angle pieces.

And finally I mounted up the Anti-Backlash Acme lead nut to the X-axis. I would have preferred to do it differently but I don’t have access to an easy way to slot the mount and this seems more than sufficient, though a bit ugly. I used a piece of 3 inch x 3 inch by 3/8ths angle aluminum to make the tab and then slotted it using the miter saw. It wasn’t perfect by any sense BUT it was suitable and a means to an end.  Maybe once I have the router running I’ll be able to re-make some of these parts I’m hacking to make work.  At least their flat and straight and align well.

I bolted the angle bracket to the 80/20 extrusion and fed the screw in.  I made a few adjustments to center the A-B nut in line with the screw an also adjusted the rear bearing block for the free floating end.  The A-B nut was a very tight and high friction fit, even when freely fitted to the ACME rod outside of the machine, so I lubed up the Acme thread with white lithium grease and connected the Gecko 540 to the stepper and ran things back and forth a few times, it loosened up a bit and is a lot smoother now.

Here’s a quick video I took of the X-axis running back and forth.  The file is just a stepped depth circle cut, so you’ll see the x-axis pause briefly at the back end of the router, that’s where the Z-axis would drop down a little bit further, then continue running the circle.

I need to do some alignment work on the uprights, the bearings on the linear rails are a little snug since I put the gantry back on top.  I’ll release the ball screw, check the measurements and add some shims and it should be all good to go for further testing.

The next step is to work on the drive setup for the Y-axis, that’s already under way but I have nothing interesting to show at the moment.  Stay tuned!

Update May 21, 2011

I’ve gotten all 3 axes working on the router now. I spent most of this week working the x-axis out and getting it going. It took a bit more work than getting the y-axis up and running and some creativity as well but in the end it worked out fine. I’ll post some more details and photos on it in my next update  (Part 11) but for now here’s the video of all the axes working together.  Still a lot of work to do on this. I picked up a bunch more screws from Fastenal so I’ll be able to permanently install a lot more parts which are missing at the moment. It’s incredible how much money you can spend just in screws to get everything put together.

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Next: Almost Finished!
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