Re: home-brew CNC lathe

JanRwl@A... wrote:

> I took the photos, and I admit, I am NOT a trained studio-

portraitist! I am

> not sure WHICH lead-screw you mean, the "X axis" or the "Z axis".

Thanks Jan, saw the screws. However, I was more refering to the first
photo:

PET-Controlled X-Y PCB-Drill
Totally home-brew.
Posted: 25-Sep-2001

Expectation to see the drive down the middle made me missed the
screws, I think, at the sides. Just like to ask 1 more question. How
does having the drive at the side rather than down the middle affect
the smoothness of the movement? Does it induces some kind of unwanted
torque/rotation that interfere with linear motion? Actually, having
the screws at the side out of the way is so much more convenient and
I think preferable if there are no minus points.

Thanks again.

So, I will

> explain both:
>
> Due to the bad "posing" of the photo with the dust-guard door

closed, you

> can't see the "Z-screw", but it leads from that handwheel on the

far-right

> into the headstock, where the "Z stepper" is face-mounted on the
> inside-surface of the headstock's left face (1.5" thick 6061-T6).
>
> The "X lead-screw" is directly fastened to the shaft of the motor

on the

> far-rear end of the saddle, and this is totally hidden by the tail-

stock

> body. However, you can JUST see the outline of the TOP of this

motor in the

> third snapshot in this group, right behind the left end of the tail-

stock

> body. That outline is the nearly-white, bright area, so intensely

lit by the

> working-lights above it.
>
> BOTH are Superior Electric bipolar KML092F07 steppers, driven by a

Slo-Syn

> SS2000DP4 dual-driver-with-power-supply "box". Opto-isolator

inputs. Works

> fine, but VERY expensive. Were I to do this same machine again,

I'd use

> Gecko G210 drives and my OWN power-supply!
>
> The lead-screws are 4 mm/rev. ACME with preloaded Turcite nuts by

BSA.

>
> Questions?
>
> The little PCB drill in picture 1 of that group can drill a board

so fast

> that I can be DONE with all the holes faster than attempting it by

hand, even

> when I include the time to measure and "type-in" the X-Y

coordinates!

>
> Now, THAT uses surplus Size-23 motors and home-brew drivers made

with a

> now-difficult-to-find 29HGA41 (or whatever) IC once made by Sigma,

later

> G.I., but who knows, now! I haven't bought one in years. Long

story!

>
>
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