adding cnc to lathe (which one)

[mark c]

Hello all
Newbie here. I've been involved in CNC for many years, running set up and programming and now want to get one for a home shop. Was looking at the Harbor Freight 8 x 12. Would this be a good one to add cnc to? I have no designs that it will be like anything I have at work ( huge horsepower, 31" swing, live tooling, C and Y axis capabilities) but want something that has a little power and rigidity. Will be cutting alum, probably no bigger than 5" dia, using Fanuc style canned cycles.
Next, has anyone done this to this lathe? I'm new to this aspect and want it to turn out "right". I've seen posts about some aspects, but haven't seen a "Adding CNC to mini-lathe for dummies". I'm sure the info is here but need a push in the right direction.

Thank you all in advance

Mark

[mark c]

Anybody??????

[cbcnc]

Mark,

I guess lathes aren't as popular as mills and routers are. I would love to have one but don't.
The only thing I know of that comes close to a "how to" for mini lathes is on the DAK Engineering site. Otherwise the home of TurboCNC.
Here is Dave's address and the article on converting the lathe:
http://www.dakeng.com/lathe.html

Chris

[mark c]

Thank you
I'll check it out

Mark

[CNCPlastic]

I think industrialhobbies.com converted one recently, you might check with Aaron over there.

[mark c]

Cool
Thanks

Mark

[gdl357]

I found this, for ideas.

http://home.netcom.com/~madynmetal/U...20steppers.htm

[mineralman]

Just getting caught up on my reading. Mark, have you looked at the Lathemaster 8x14 to CNC (www.lathemaster.com)? You mention you want something solid and rigid, and this one is truely head and shoulders above the 7x12 or 8x12 lathes (no affiliation, blah, blah, blah. Just a very satisfied owner of one.) I used to own a 7x12 but recently sold it.

This is not totally altruistic, as I'm contemplating CNCing mine, and would surely like someone else in the same boat so to speak.

Larry
New Orleans

[RotarySMP]

My feeling (having converted a 7x12) is that you should get the biggest, least featured, cheapest, most rigid lathe you can.

Most of the discussion of the various flavours of 9x and 8x lathes centers around the half-norton gearbox, wobbly compound, cross slide feed slot burrs, change wheels etc.

When you do a CNC conversion, all this stuff ends up at the tip (actually collecting dust in a box under the bench

There are a few really stripped down models of 9x out there, and that would be what I would go for. Aim for one with a t slotted cross slide. From what hve gathered all the chinese 8x and 9x lathes are decendants of the Austrian Emco's which were 7x lathes. The 9X has quite a tall headstock and is thus less rigid.

Toss the single phase chinese motor and put on a treadmill motor and controller or three phase and VFD on the spindle.

Toss the leadscrew and mount a ball screw. Toss the apron and hang the ball nut on a plate.

Toss the compound, make up a ball screw drive for the cross slide. Mount a Phase II AXA to a plynthe. Build an enclosure. Add an spindle encoder. Run TurboCNC on an old Pentium or celeron, will be up and running.

It was just a shame I don't have space for a 9x lathe, as I end up torturing the 7x12.

[mark c]

Thanks for the ideas guys. I'm going to buy something, but not as soon as I'd thought. Probably not for a month or so. I'm still reworking my micro-mill. Lots more work than I'd thought it would be.
I'll probably go for the Lathemaster 8 x 12. I want something that's strong as well as "ready to go" as far as slop and squareness goes. I do plan on using TurboCNC, if only thats what I'm familiar with. Would like to run a different motor and encoder too. Just not sure how to do all this. Will be asking lots more questions in the future.
Larry, we'll collaborate for sure here. Nice to have parallel effort in a learning process. Let me know if you start anything.

Thanks again guys
Mark
mccoates@sbcglobal.net

[RotarySMP]

For an encoder, turbocnc is only looking for a one pre rev pulse, so there are some really simple ways to get it. I used Dave K's circuit and an optical gate, but even easier are the optical gates with the driver and schmitt built into them. Then you just need to supply 5V, gnd and a signal out pin.

[balsaman]

Thanks for the ideas guys. I'm going to buy something, but not as soon as I'd thought. Probably not for a month or so. I'm still reworking my micro-mill. Lots more work than I'd thought it would be.
I'll probably go for the Lathemaster 8 x 12. I want something that's strong as well as "ready to go" as far as slop and squareness goes. I do plan on using TurboCNC, if only thats what I'm familiar with. Would like to run a different motor and encoder too. Just not sure how to do all this. Will be asking lots more questions in the future.
Larry, we'll collaborate for sure here. Nice to have parallel effort in a learning process. Let me know if you start anything.

Thanks again guys
Mark
mccoates@sbcglobal.net

It's good to know that the Lathemaster 8x14 is the same as the Harbor freight 8x12. I own the HF version, and reviewed it here:http://www.cnczone.com/modules.php?n...rticle&artid=6

Up to today I thought the Lathemaster was 2" longer, but today I took my chuck off and installed the #3 morse taper dead center in the spindle, and it measured 14" center to center, so the HF version is also 8x14.

The lathemaster comes with more accessories. It's also $200 more. It's never in stock.

Eric