Any other CNC hobby machinists here?

I'm doing a CNC conversion on a Harbor Freight 7 x 10 benchtop lathe. I'm about 90% done, with a few misc. items to finish up on it. Here's some pics.

Tried to embed a YouTube vid, but it didn't work like I thought it would.






http://www.youtube.com/watch?v=8tX5gzBz7Nk

 

Wow that looks pretty sweet. I didn't even know that you could convert something to CNC. Take pics of what it can do someday when it is operational.

 

Unbelievable, rep for you. What do you do for a living?

 

Thanks guys, I was a machinist for several years, followed by doing tool design for several more years. Now I work at Toyota doing new bodyweld equipment installation.

Hobby CNC has really come of age, it can be done as cheap (as in my conversion) or as expensive as you want.
I'm also working on a 4-position automated tool changer for it.

 

I went to school to be a Machinist but ended up a UPS driver.I sold all of my tools but i would like to get back into it on the side. I miss all the fabricating.

 

Machining is awesome, but it's really hard to beat UPS for a great career. Benchtop machines can be had pretty cheap at Harbor Freight. Right now the 7x10 lathe is on sale with coupon for $350. I think it's normally about $500

 

Very cool, I've been wanting to convert my vertical mill for power/controlled feeds on the x and y axis. I would be interested in more info on the motors/steppers and drivers your using?
I'm guessing your using pc based software for control? Something you purchased or wrote yourself?
Thanks

 

SUB'D! make me parts!

 

Lol, not machining anything yet Anthony. I will probably machine aluminum, hardwoods and plastics on it. I really don't have anything specific to make on it, the lathe CNC conversion is a hobby in and of itself.

Geode, what kind of mill do you have? Pics?
You can get CNC control boards off ebay for around a hundred bucks, but the best unit and one of the easiest to hook up is a Gecko G540, which is what I'm using on my lathe. If your mill is a full-size mill, this may not support large enough stepper motors. If it's a bench mill, it should work great. My old bench mill used a really cheap board & small stepper motors I got off ebay, before I really knew anything about doing the conversion. It moved the table, but the steppers were too small to do any real work. You need stepper motors powerful enough that you won't lose steps (thus screwing up the part program). Right now I'm running the free version of Mach (just Google Mach CNC). Down side to the free version is that it doesn't support threading. The registered version does, which is $175. Not sure if I will use that, or one of another few free CNC programs available. Mach has the best user interface.
If you want good info on CNC conversions, check out www.cnczone.com
They have a ton of sub-forums.
Here's my lathe thread and Here's my mill thread



Here's a pic of my ultra-cheap conversion I did on an X2 Harbor Freight mill a few years ago. Sold this mill due to moving and not having room for it, but I kept my lathe

 

We've done a little bit of cnc work on my computer integrated manufacturing class. Nothing too drastic, just learning the basics and what not. We used auto desk inventor to make the parts then ran it through a few programs to get the codes written. Originally I had planned to make a circular box with sort of a gear tooth edge if you can imagine that with "Trd" on the top. The trd part took forever and when I finally got finished realized we didn't have the right bits to make it. Well anyways enough of that haha that looks sweet!

 

The mill is an enco model, it's bigger than a bench top model but not a lot.
I looked at the Gecko drives last year, they look really good.

The biggest hurdle for me seems to be making sure I get a stepper motor with the required torque, which also affects the drive obviously. It looks from your pictures that the stepper motors axle runs through the motor, so you can still use the hand crank?

Your setup looks great!

 

better picture.

 

Nice mill!

The motors I'm using on the lathe are a dual-shaft setup, so I just attached the hand crank on the other end of the motor.

If you want to use a Gecko G540 for the controller, the best motor to use with it is a 381 oz. in. stepper, which should have plenty of power. You could even do a 2:1 timing pulley reduction to achieve even more torque, which wouldn't be a bad idea since your mill is good sized.
IIRC, the 381 oz. in. motor is the optimum motor for use with the G540 controller. You can use larger or smaller motors (mine are 254 oz. in.) but you lose a little more power. I got my motors at www.kelinginc.net
The 381 motors are about $50 each. Keeping it cheap, you a probably do a simple 2-axis setup for around $500. If you went with ball screws, you'd be pushing $1000 or so, as there's a lot more involved when you retrofit to ball screws. They're really nice to have, but not really necessary for home/hobby use. Seems like most people that do CNC conversions go with ball screws. My lathe has ACME screws, and it will be fine for my intended use.

 

Hey thanks for all the information. I would probably go with the reduction to pick up the torque, and speed is not an issue. Thanks again, it will be a few months but hopefully I'll get the chance to retrofit the mill by summer. Incidentally, the mill is quite good for being a "cheapy". I want to say I paid about $1200 new. I used a similar mill at work for a few years and was very satisfied with the performance.

Regards

 

I love it! I almost went this route, the conversion is pretty easy if your the mechanical type, I didn't have the room...dont have the room...yet

I grew up in a small town in Montana...on a ranch. I remember as a kid my uncle had this crazy lathe he built himself to turn pieces of industrial equipment...Wagner...Skidder...Semi Truck drive shafts...the lathe was maybe 25' long. He had a motorcycle transmission with the chain and sprocket to power the lathe of a electric motor, the same lever you would kick with your foot when shifting gears on a motorcycle sat right next to the floor. I remember him shifting gears turning various pieces and teaching me the fundamentals...I loved it! I recently spoke with him to ask what would be a good setup for hobbyist type work...what you have is pretty much what he recommended. He told me to hit up the government auctions and find the old WWII equipment...solid stuff...buy some CAD equipment and your good to go.

I have had so many obstacles with my projects in the last couple years, all needed was a damn lathe! This would be a great solution.

 

No CNC here, I turn handles....

HF8X14 & PM12X36

 

Beautiful lathes, love the 6-jaw on the 12"

Mjohn, that old lathe your uncle made sounds pretty awesome... A motorcycle transmission, very sweet! Yeah, auctions would be a good place to look. Old WWII equipment is crazy heavy-duty, and can be had cheap. Might be a pita to move though, due to the weight and size.
That Harbor Freight 8x12 that zero4 has in the pic (the smaller red one) is an excellent hobby lathe. I would love to have that one, but needed something that I could move around myself, and the 8x12 was a bit too heavy.

 

at work we've got 4 haas cnc mills. a haas cnc lathe. an old hitachi cnc lathe. a cnc bridgeport and about 5 other bridgeports with digital readouts. we've also got a big old horizontal mill.

ive run most of them but dont have much experience with programming.



that harbor freight mill you put together is awesome for home! what did that come out to after all was said and done?

 

Thanks. I had em on both lathes. 5" & 6-1/4"

Yup, the 8x14 is definitely too heavy to move around by yourself. My brother & I struggled a bit getting it up on a high bench.

What HF calls the 8x12 is actually an 8x14. It is the same lathe as what Lathemaster sells (CQ6120X320) but without all the accessories. They are made in the same factory & are said to even follow the same serial number sequence. The backsplash on mine is actually from Lathemaster, HF discontinued that & it can't be purchased anymore (it does not come with the lathe as they picture).

Definitely a great starter lathe & with just a few minor tweaks it can turn out great parts. If anyone is interested & I can give you tips on what to improve. I was lucky I purchased mine on sale & stacked a 20% coupon (HF got smart & won't let you do that anymore). I paid $361 out the door 2 years ago.

 

Holy CRAP! $360 OTD? That's about the same time I bought my 7x10, which I got the same way you got your 8x14, but I was $320 OTD. So did that 6-jaw cost about twice as much as the lathe?
BTW, HERE is a good source for replacement parts for just about any HF or Sieg machines.

@ Owrx2, check out the link I posted to the mill, it gives the part numbers for the purchased parts. OMG, it was DIRT cheap to do that little conversion! Check out the thread, and look at the simplistic parts that I made for it. LOL, I'm almost ashamed of how simple it was! I bought a package deal that had 2 motors, the controller, cables, and power supply for like $100.

BUT, the motors and the controller board were not appropriate for that setup at all. The motors were way underpowered, and they lost steps easily. You can get decent motors for about $30 ea. But like anything else, you can spend as little or as much as you want. There are a lot of cheap Stepper Controllers on ebay, but I have no clue as to which ones are decent and which are junk. I'm using a Gecko G540 controller on my lathe, which is an extremely popular unit due to it's unmatched performance and almost idiot-proof hookup. It's pretty much the de-facto standard for small machine conversions. That unit alone is around $300. It will control up to 4 stepper motors. You also need a 48V power supply, which is around $50. Add a printer cable and a couple 9-pin cables and you've got pretty much everything you need. I used the existing ACME screws on my mill, but most people opt to replace them with ball screws. I just wanted to keep it simple and cheap, so I didn't get involved with swapping out the screws.

EDIT: just finished up this little addition to the lathe, a powered tailstock quill. Not really needed, but I thought it would be cool.

It's not running a program in the vid, just a little jog move.

http://www.youtube.com/watch?v=rniq3hdyT1k?fs=1