Re: [CAD_CAM_EDM_DRO] Build my own CNC lathe - possible?

Alan Jack,
 
            Having had the oportunity of working with HLV Hardinge Lathes for twenty years, my preference wiould be an old one, retrofitted with E-Leadscrew, and Mach3, that would be a real good setup, just my opinion, for what it's worth,
 
I noticed a chucker on ebay $2000 us,


........Edmund.........

--- On Sun, 4/11/10, Jack McKie <freshwatermodels@...> wrote:


From: Jack McKie <freshwatermodels@...>
Subject: Re: [CAD_CAM_EDM_DRO] Build my own CNC lathe - possible?
To: CAD_CAM_EDM_DRO@yahoogroups.com
Date: Sunday, April 11, 2010, 2:14 PM


 



Alan,
 
You might be able build a better CNC lathe from more or less componants than you would end up with by retrofitting a manual lathe.  I think that the cost of the linear beqarings and ball screws would be a lot less than a good lathe and they don't require complicated lubrication systems.
 
I have two lathes that I have considered retrofitting but decided not to since I would prefer to design the lathe with the type of products I want to turn in mind.   Ideally I would like to use a headstock from a commercial lathe.   A 5C Hardinge headstock might be ideal.
 
On the other hand an old Hardinge Chucker lathe makes a very nice cnc lathe.  One shop I worked in had a chucker with a gang of tools on the cross slide.
 
Jack

--- On Sun, 4/11/10, Alan Rothenbush <alan@...> wrote:

From: Alan Rothenbush <alan@...>
Subject: [CAD_CAM_EDM_ DRO] Build my own CNC lathe - possible?
To: "CAD" <CAD_CAM_EDM_ DRO@yahoogroups. com>
Date: Sunday, April 11, 2010, 2:40 PM

 

Lazy Sunday morning, drinking coffee, daydreaming and a crazy plan starting to coalesce.

1. I've CNC'd my old Sherline lathe and have been playing with it in earnest, to get my head around the use of a CNC lathe. (Long time user of a CNC'd mill).

This pretty cool!

I took the trouble of adding manual handwheels to it (just in case) but I can see that a nice MPG will completely obviate the need for these.

Problem is, there's some backlash in the system and due to the age of the Sherline, it's not easily removed. (Uses the OLD style leadscrew nuts). I'm compensating in software, but of course that's not the same thing.

Still, a CNC lathe is cool.

2. My primary lathe is an old Southbend 9" x 18" that's a bit of a Frankenlathe; bed, headstock, saddle and tailstock are all from different machines. It still turns out pretty good pieces, I think, but there's a TINY bit of taper and a TINY bit of roughness in the turning, a bit more play in the nuts than I'm happy with, bit of wear in the cross slide, a slightly sloppy tailstock and so on.

None of the faults are show stopping, but there's enough of them that I've gotten it into my head that I want something better, plain and simple; something NICE, and preferably new or nearly so.

Now, it's about the biggest machine that will fit my space and it will do 99% of what I typically turn, so I REALLY don't want to contemplate anything bigger.

Looking around, though, for "new" and "nice" in a benchtop of that size, the pickin's are slim; really, all I see is a Prazi D6000 for $6500.00 That's really outside my price range as a hobbyist.

3. Whatever I buy, I'd have to CNC; no question. I'm hooked. So even if I did talk myself into $7k (adding in taxes and whatnot), do I really want to start drilling holes in a brand new machine? Probably not; I'm not that brave.

4. Staring at the McMaster Carr online site and peeking at eBay, I keep looking at all these linear rails and I've got to wonder; couldn't a guy build his own CNC lathe for a WHOLE lot less?

Some stout linear rails fastened to a suitable base (the ground flat bed of an old lathe, for example). Standard linear slide for the cross slide. Ball screws.

Use an existing spindle out of something, maybe even another Southbend so all the existing attachments can be reused.

Fab up a headstock and line bore it right on the machine itself; same thing for a tailstock.

Sunday morning on the couch, this SEEMS doable. Am I dreaming? Hallucinating? Any opinions (including "you're nuts") appreciated.

Alan

[Non-text portions of this message have been removed]








[Non-text portions of this message have been removed]