Building a CNC - Frame modifications and (re)assembly

Now for the frame.

First I had to fix a construction misalignment (explained in the picture bellow), that caused the the stepper motor axis to collide with the linear rail bar and twist and rotate eventually breaking the coupler in two.

I did it by cutting the corner stuffing (inside the cutted tube and over the corner) a metal bar that I had laying around (and was pretty much the height I needed), and then weld it and cut it to the desired length. The picture gives a clear idea. The fact that the bar entered in the tube also acted as an reinforcement. I was quite happy with the result.

Modifying/fixing the rail angle

One other thing I didn't liked in the initial design was the bottom bars in the frame. The initial idea was to put the bottom plane over these bars. But any millimetric offset would mean that the "floor" of the CNC would be like bump or a dip. So I removed the bars, used them to reinforce two of the sides (for the axis that clamps on the top side. The bottom side would probably cause collision problems) and the corners in the bottom square.

Modified Frame

 To finish I gave it a black paint cover and the axis a red tone as you can see bellow.

After the paint job

Finally I reassembled the CNC and gave it a spin. It's a working machine. OHHHHH YEAHHHH.
The picture bellow was taken before all electronics were in place but the machine is all now fully loaded and tuned.

Assembled Axis and Frame

Now I must thing of a name for my baby/beast CNC..hummmm
More modding is on the way. Electronics are next. So stay tuned...

Building a CNC - X and Y axis modifications

I've been working on changing some less well thought/crafted parts.

The way the RM1605 ballscrew thread was mounted/fixed on the X and Y axis was one of them. The fact that I was depending on some rubber pads to align it with the stepper motor shaft was not ideal and was a source of alignment issues.

To fix that, I rotated the BK and BK block by 90º, so it would stand on it's side. These block are 60cm wide (aprox. the same as my NEMA23 stepper motors) and allowed an almost instant misalignment free position.

Here is the new supports welded to the X axis.

New supports

X-axis fully assembled

To be continued...

Building a CNC - The end (a new beginning)

After a 8 months break I restarted to think on my CNC and the away I could put this puzzle together since I didn't thing the design all the way through.
It toke me about 4 hours to come up with a plan the result was a working CNC :-P.

I actually had to undo a couple of parts I have showned in past posts, and replace others. To make the last parts and since no welding was needed, I used aluminium rectangular tubes (easier to work with).
I've also relocated all the electronics to an old Pentium II PC that I had laying around, and now have a neat single tower PC/Controller solution that I will also show.
In the next posts I'll try to show what I've done to assemble the CNC, what I've accomplished in terms of results, and some of the problems I've encountered and I'm currently fixing/working.

To be continued...