Re: My CNC Mill retrofit project

>Message: 3
> Date: Fri, 08 Oct 1999 12:50:38 -0500
> From: Ray Henry <rehenry@...>
>Subject: Re: My CNC Mill retrofit project
>
>
>Andrew
>
>I figured it out. This is just like back in grade school when the teacher
>baited a hook and cast it into the classroom. I always raised my hand and
>got suckered in - until I finally became sullen, non-responsive, and was
>labeled MR. (Way back then they didn't have degrees of learning disability)
> And all of that happened in first grade.
>
>Your post reminded me of the movies "Lethal Weapon x" where they always
>argue and then manage to snip the wrong wire. Time and again I've stared
>at machine wiring and wiring diagrams for hours trying to understand a
>relatively simple machine failure. (MR strikes again)

[Well, I really hope I don't snip the wrong wire- there's a lot of delicate
electronic gear in this thing that is itching to go up in smoke...]

>
>To splice in a new machine brain is not a trivial task. But it should be
>instructive for all of us if you take the time to sort out and clearly
>doccument each step and each decision in the process as you make them.

[I can do that. No decisions yet, though.]

>Have you got enough web space to allow for an on-line running commentary as
>you complete this project?

[Oh, sure- I've got plenty of web-space. What I'm running out of is
Physical space.]

I'd be happy to work on some of the pages and

>diagrams.

[Thanks, it was more hassle scanning those blueprints than I'd imagined. I
had to get in there and rewrite a lot of labels so they'd be legible, ]

I could start by cutting up your .gif's so they could be more

>easily viewed.

[I thought of doing that, but then it gets difficult to figure out the
connections between one part and another. I think there's a Java applet
that lets you zoom in on parts of an image, but unfortunately I don't speak
Java- parlez-vous?]

>
>From the photos and diagrams on you site it looks like a nice little
>machine.

[Little? It makes my Bridgeport look like a dwarf.]

I'm not familiar with the brand. Is it manual tool change or is

>there a tool caroussel and a changer arm?

[It's got a quick-change collet, but it's manual.]

>
>I just glanced at your wiring diagrams and the power to your old system
>looks a bit like this:
>
>1. Three phase 220 volt power.
> Into machine through main disconnect and fuses --
> to Lovejoy?

[I think that's right. The Lovejoy seems to vary the speed of the spindle
motor.]

(spindle oil cooler?)

[I'm not sure it's got that.]

> through reversing starter to knee motor
> through starter to flood coolant motor

[Sounds right. Would these still be 3-phase?]

> legs 1 and 3 feed through a line filter to a control transformer
> legs 1 and 2 feed a drive transformer through some kind of
>resistor/relay set

[There are a couple of good-sized transformers, I assume one runs the DC
servo motors. What's the other one for- the control circuit?]

>
>Will you keep it three phase?

[Yes, that's the plan.]

>
>Matt figures that you need opto 22 stuff. It looks like there is some
>already there. They're shown in the top center of the bottom right photo.
>
>http://www.computersculpture.com/rammill_page.html

[That's what I thought- they're arranged in a vertical line in the middle
of the control box.]

>
>It looks like the cards hold four devices each and there are three of them.
> Your mill gif shows them between the power supply panel and a row of
>control relays. That part of the drawing is laid out the same way the
>control box is laid out.
>
>If I'm reading these things right, the photo shows 8 opto devices in place.
> The layout shows 10 being used. The schematic shows 11 being used.

[Does that mean I need some more?]

You

>might want to keep the 110 volt wiring (red maybe) from these opto devices
>to the relays/contactors that they control in place for a while.

[I was intending to keep as much intact as made sense- is it possible to
keep both control systems alive at once?]

Your new

>wiring from a parallel port or stg or (?) would go to the input screws on
>these boards.
>
>Ray

[Do I need to hook up a 25-pin plug to these? What about the feedback loop-
how do I find the output from the encoders? Does the EMC program require I
use a STG board or the equivalent? Thanks for the input, Ray- this stuff
really makes me feel retarded...]

Andrew Werby

>
>

Andrew Werby - United Artworks
Sculpture, Jewelry, and Other Art Stuff
http://unitedartworks.com