[cyberkeith]

Started this build a long time ago. I am just now getting to the fun part of seeing the computer starting to take control.
Have run into many problems along the way. Wrong parts from China, broken drill bits in aluminum, remaking parts due to both my errors in scribing and some parts having holes drilled wrong from overseas.
Still plenty of work ahead, and I love every minute of it!
Attachment 222632

[CarveOne]

There are always problems of one kind or another when building one of these machines. The trick is to stay focused on the end goal. Namely, whatcha gonna build next?

[cyberkeith]

Just about finished with the Z Plate. Bought a router mount which fits great. Here are some pictures of the layout during the process.Attachment 226816Attachment 226818Attachment 226820Attachment 226822Attachment 226824Attachment 226826

[matth]

With the layout of your frame wouldn't it be an idea to run a heavy brace across the bottom of the gantry uprights? This would stiffen the structure further.

Nice looking machine so far.

[cyberkeith]

Plan to add cross brace if needed. I left room for it.
Today started to add limit switch to the z-axis.Attachment 227112
Very small screws using 4-40.

[cyberkeith]

I see so many sizes to choose from and feel a little overwhelmed. Also concerned with quality, when on a tight budget. I plan on adding a water cooled spindle so I think that will affect the size choice any input would be welcome.
Thanks, Keith

[cyberkeith]

1st Cut is attempt to test by surfacing the top MDF layer. using 3/4 router bit.Unfortunately the motor coupling broke just as I finished the second pass.
The couplings are cheep ones that came with the screws.
Started reading some about this and see that these probably allowed too much backlash, combined with slight a miss-alignment, my fault. Few days for new parts.
Motors are 495oz, driving 2005 screws. gantry total weight is 133 lbs.

Any input is appreciated.

Attachment 236590Attachment 236592Attachment 236594

[tauntdesigns]

Bummer

But, it looks like it was cutting good until the mishap.

[Devastator]

At least it did what it was supposed to do and saved your motor shaft.

[ger21]

While those couplers allow a little bit of angular misalignment, they don't tolerate much axial misalignment at all, as you've seen. It's important that the motor and screw are perfectly aligned.

[cyberkeith]

You are completely correct Gerry, the alignment is off on this one. I will have to make aa new plate and re-mount the motor. I knew this was off a bit, kept speeds lower, but this did not last but maybe 4 minutes of steady run time.
Attachment 236810
Was running at 70 ipm.
Thanks for catching that.
Keith

[cyberkeith]

Received new coupler today. Now to make some changes and make sure everything is lined up correctly. I have re-made three motor mounting plates over the course of this build. Hopefully soon, I can use the CNC to make new parts for itself at a far greater accuracy then I am able to achieve.
Attachment 237014Attachment 237016

[nlancaster]

Instead of trying to make parts perfectly accurate, why not build in adjustments. Example, that misaligned stepper mount, just take that mount and enlarge the holes, and possible oval them to allow you to position the stepper perfectly inline with the ballscrew. Problem solved.

[Ken_Shea]

What nlancaster suggested was my first thinking as well.
Those are much better couplers for strength.

That sure is a nice build Keith.

[cyberkeith]

i slightly enlarged the mounting holes on the FK12 bearing block, then flipped it 90 degrees and that was enought to bring me pretty close to proper alignment. Went back to same coupler since the space between the two shafts was just under what the new coupler required. Installed that coupler on the z Axis.Attachment 237260Attachment 237262
Top of z-axis
Attachment 237264
Attachment 237266
Should finish up in another day.
Need to check on how tight to set the locknut on the bearings, not sure. Have them all just snug. Even with a 133 lb gantry, it only takes a feathers touch to turn the ballscrews with the motors detached. No binding yet.
Keith

[cyberkeith]

Doing some simple engraving with the CNC. Learning the software end of things here. This forum has been so much help in understanding. The information everyone shares on thier own build experience helps us who struggle in uncharted waters.
This Fish I cut last night was about 10,800 lines of gcode. I used the open source program Pycam to convert it from a DXF file.
Attachment 237756

[cyberkeith]

Small gcode programs that work well for testing, I found these on this forum... Thank you
Attachment 237758

[cyberkeith]

Cutting Acrylic today with new Bit...

Much better then my first try with wrong bit
Attachment 249268

Attachment 249270

thank you cnczone members for directing me to the right bit!
Keith

[bobmagnuson]

Wow, what a difference the correct bit makes. What bit did you end up using?

[cyberkeith]

I used Onsrud 63-530 up, 0 flute end mill. First cut was 1/4 inch deep, then full depth at 0.460. just the two passes.