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Wannabe
03-20-2004, 02:29 PM
Hello
First thing I'd like to say is that this site is great, lots of info.

I've been browsing this board for a couple of weeks and now I have the itch to modify my mill. I'd like to get some feedback on what type of setup I should go with for cnc mods. IF it's even possible?
Thanks
Here are some pics so you know what I'm working with.
http://www.mustangboss302.com/stuff/mill1.jpg
http://www.mustangboss302.com/stuff/mill2.jpg
http://www.mustangboss302.com/stuff/mill3.jpg

HuFlungDung
03-20-2004, 02:46 PM
Well, I dunno, but I wouldn't sink any money into that one :D

Shop Ebay for any old cnc vertical machining center. Sometimes, you can find a steal on there for $1500 or so, on a machine that is already converted, with ballscrews and servos and everything, but maybe a dead controller (or a Bandit, which is the last step just before a machine moves towards the light :D)

Wannabe
03-20-2004, 03:22 PM
You makin fun of my unit?:D lol
Actually this thing is very accurate, thats why I was even considering cnc. I've made some nice parts with it over the last 20 years.
Maybe I will just convert to some type of power feed on it.
I feel like windmill Johny when I run it:D

HuFlungDung
03-20-2004, 03:46 PM
No... I'm not making...well, yes, okay, I admit it, I was poking a bit of fun :)

Really though, you can pick up some good used iron at a decent price and still have the fun of going through it and wiring on a new controller. I purchased a 20 year old, $130,000 USD turning center that was worn out. I paid $6000USD for it and spent $40,000 on it and it is better than when it was new, except for the air chuck which I have not replaced. That was with a professional retrofit done with a Mitsubishi cnc controller, and new servomotors. I had the bedways reground and new Turcite coating installed, new super precision spindle bearings and all new bearings throughout the rest of the headstock.

Knowing what I have learned since, I could have saved $10k or $20K by using a PC based cnc, but back then, the economy was cooking, so it didn't hurt so bad to outsource the retrofit.

One thing I would be looking for in a mill is enough table travel, and spindle to table distance to get a vise, some work and a drill bit to fit in the available space. This requires a minimum of XYZ of 20 x 10 x 14 work envelope. In actual machining conditions, you will find the work envelope gets considerably smaller than the machine travel specs. Too small = useless because the investment in ballscrews, motors and controllers is practically a fixed cost for this class of machine. So get the most for your money by buying "good used iron" (with ballscrews already present and mounted).

This is just my opinion, of course, as a general machinist looking for maximum versatility per $ spent.

HuFlungDung
03-20-2004, 04:28 PM
Here's one. Might be ballscrewed in XY and not in Z. The description is pretty short.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3804999612&category=12584

Wannabe
03-20-2004, 07:35 PM
I totally agree with your thoughts.
I originally wanted to do a small benchtop mill, THEN I had the vision of doing this one.:D
This pc/cnc stuff is all new to me, and thought if I did the mill I have as a project, I could learn how it all works.
I may go ahead and try it, I will only be out my time, as I can use the parts on a better mill if it does not work.

I only use this mill for a hobby and to make parts for friends, I guess I'm really more interested in building it to get a grasp on cnc than anything:)