Re: Bridgeport! (a BIGGER brother!)

Joe,

Thanks for the additional information. I'll go take another look at the
Bridgeports I saw (without the wife). But I think they were saying 3-4
grand. Not that that was a "final" price. Care to post a pix? High
detail, something I can print out on my laser printer and take to the
shop. I'm sure I saw handwheels. HUGE.

The stepper motors would be perfect. And I have driver cards for
unipolar motors, as well as power supply. I even think I have room in
my garage, er, shop! As long as I can get riggers to move it in for me.

Alan KM6VV
P.S. RANT ON! Good info!

Joe Vicars wrote:

>
> Guys,
> I think you are missing what I am talking about. A Bridgeport Series 1 and 2 CNC were made by the thousands in the 80's. They
> used stepper motors, open loop, 1/2 step unipolar drive. The two machines are identical except for the knee and table. The series
> 2 weighs about 1000-1500lbs more because of a larger envelope (something like 15 x 30 vs, 12 x 18 for the series 1) Most had a
> rigid ram, but some had the regular V-ram style although these are much less rigid. Some have power drawbar, but most I have seen
> have quick change Ericson 30 taper spindle.
> These are not converted Bridgeports, they are dedicated CNC. No handwheels, ballscrews all around and 10 times better Z than
> you get in ANY retrofit of a standard bridgeport head.
> All you have to do is replace the stepper drivers with new ones, and put a phase converter on the spindle motor. That's it!
> You can do the break by hand and blow shop air into the speed control when you want to change speeds, or it's just as easy to hook
> up the air controls.
> As Tim pointed out, the motors won't run at their OEM performance level, but so what? We're talking home shop here and 30 ipm
> should be plenty
> Someone tell me where else you can get a full size 3 axis mill for less than 2 grand?
> The ONLY disadvantage is the size. Many guys may not have room. But I tell you I have a 10' by 20' with only a 7 foot ceiling
> and I would never go back to my old JET. You guys with basement shops would have real trouble with it.
> I don't care where you live, if you look around you will find one dead and rusting off in the corner somewhere. If you can't
> find one for less than 2 grand you're not looking hard enough.
> End of rant.