Lookin' to go CNC on my lathe

[Justturnin]

I have been looking into setting up my Griz Lathe as a CNC. I have found tons of stuff showing off a completed conversion but little on what is necessary to complete it. Does anyone know of a good book or website that could break it down for me? I dont just want to do it, I want to know how to use it when I am done too... I have some things I want to try to make and they cant really be done manually and consistent at the same time.

Ohh yea, I know there are forums dedicated to this and I will likely be joining a couple once I get ready to take the step but wanted to see if anyone here had done it.

 

[cwolfs69]

I have been looking into setting up my Griz Lathe as a CNC. I have found tons of stuff showing off a completed conversion but little on what is necessary to complete it. Does anyone know of a good book or website that could break it down for me? I dont just want to do it, I want to know how to use it when I am done too... I have some things I want to try to make and they cant really be done manually and consistent at the same time.

Ohh yea, I know there are forums dedicated to this and I will likely be joining a couple once I get ready to take the step but wanted to see if anyone here had done it.

go to the grizzly site. i believe they sell a kit to convert and instructions.

 

[Paul in OKC]

go to the grizzly site. i believe they sell a kit to convert and instructions.

They do, but I think it is pretty spendy. Will have to do some digging. I think I ran across a site a bit ago on this. In the mean time, the cnc zone site is a decent place for info.

 

[Justturnin]

go to the grizzly site. i believe they sell a kit to convert and instructions.

I didn't even think to look there. Looks like they are for the mills and are pretty pricey.

Will have to do some digging. I think I ran across a site a bit ago on this. In the mean time, the cnc zone site is a decent place for info.

I tried to register w/ CNCzone but I get a message that registration is disabled by the admin.

I found a setup on ebay for about $175 w/ 3 stepped motors but I know there is more HW that must be invested in to be able to mount and connect like new screws and such but not sure what else.

 

[mredburn]

I have found it is sometimes cheaper and easier to buy a cnc lathe and resell your old lathe.
Less hassle and the difference between the old lathe and new cnc lathe is less than the conversion costs.

 

[Ed McDonnell]

Are you sure you want a CNC Lathe? A cnc lathe will make round stuff fast with a high degree of repeatability, and be able to easily produce crisp v cuts without tooling changes.

A cnc router / mill with a rotary axis will make any shape. Round, oval, hexagonal, spiralled.....whatever you can imagine. It will also do 3D carving / engraving in the round.

A good cnc lathe will make round stuff faster than a cnc router / mill (with rotary) will make round stuff. A rotary capable cnc router / mill will make many more things that are just not possible to make on a cnc lathe.

None of the cnc hardware will do much useful if you don't know how to generate the code to run them. Good software that will save you from having to manually write the code ranges from "WOW!!!" to "eye-poppingly, head explodingly" expensive.

Just some thoughts.

Ed

 

[mredburn]

Ed has a good point, have you researched software to generate the G-code or looked at whether or not you can write it yourself?

 

[randyrls]

I will add to Ed's comments that Don Symonds (sp?) some time ago showed (here?) some dynamite engraved pens. I suspect you could even do metal overlay engraving.

 

[skiprat]

I love Mike and Ed's replies. I too have explored this avenue and decided that one day when I win the lotto, I will get a pre-made CNC mill with the 4th axis ( rotary table ). I would want it to work stuff like stainless and titanium though.
I do however want to one day build a basic 'flat wood' version, just for the learning curve.

Like Mike says, all the stuff bought individually really adds up. Controllers, steppers, new ball leadscrews, software....etc etc.
And of course the ability to accurately modify what you already have.

But don't give up to soon. Join the forums mentioned for a few months first. But please don't just buy a bunch of stuff off the interweb. You'll really just waste your money if you try to cobble it together.
Good luck!!:biggrin:

 

[mredburn]

I had a std Taig benchtop mill. I bought a barely used cnc Taig mill for less than the conversion pieces after I sold my original std mill. Plus there are handles on the stepper motors so I can still use it as a manual mill. There are a lot of people that find its not as easy as "push a button" and make parts. The cnc mill was cheaper than the software I bought. I have modified my Sherline lathe to cnc. It will cut parts but I havent found the time to learn G- code and I havent found software that I will buy just yet. Even with cnc capabilities it wont cut threads. For that you usually need a tach plugged into the controller to read the rpms, and a variable speed motor that is controlled by the controller. It is definetly not impossible but do a lot of research by other that have done the same model.

 

[mredburn]

Oh and with all the talk about software and G-code you will need to buy or build a controller for the machine. I have done both. More $ to the list.

 

[Paul in OKC]

CNC Fusion, Mini Lathe CNC Conversion Plans - LittleMachineShop.com, http://www.xylotex.com/, http://www.mini-lathe.com/CNCmlrs.htm
Couple of links to some info.

 

[Justturnin]

Thanks for all of your input guys. That is why I asked here.

Paul, just great links. I think my main deal would be to put a shopping list together to make the conversion so I can get an accurate price list for it.

I have looked at some CNC lathes but they are smaller than my lathe and I don't want to give up the size of my lathe for CNC.

Ed, you are sure right about the Mill and I have one of those on my radar too. It may happen before the lathe because I may end up needing it to manufacture the parts for my lathe.

Programs, I am aware of them and their cost for a good one. I have no experience with them but all that means is I have to learn, that does not bother and even kind of excites me.

From what I have seen online a conversion will run about $1k - $1500 and from the parts I have been able to identify I assume most of that is software so I would hope it would be a one time purchase and then I can use the same software to run the lathe and mill if that is what I end up with. Either way this post is step one in my research and it will be a while before I pull the trigger if I do.

EDIT:
hahha....or maybe most of that cost is the ball screws... I just looked them up.

 

[Ed McDonnell]

There are always going to be tradeoffs between cost and capabilities.

Acme threaded rod with anti-backlash nuts will give pretty good performance in soft materials at a tiny fraction of the cost of ball screws. Skate bearings running on plate metal rails or bronze sleeve bearings on hardened steel rods (preferably fully supported) work pretty well at a tiny fraction of the cost of industrial grade linear bearings. Stepper motors are a lot cheaper than servos, but are less tolerant of operator error in many ways.

If you want to work stainless and tungsten, you will need to spend a lot more than if you are talking about wood and plastic. For me, half the fun was learning as I built. Fortunately learning new stuff was fun because there was a whole lot of learning to be done.

Buying a machine, plugging it in and getting to work is great. But there is something special about building your own machine from scratch and having it turn out work that far exceeds whatever you expected to be able to do.


Ed

 

[ironman123]

Chris, I went Xylotex 3 Axis on my Micro Mill and when I bought a Rotary Table, I bought a single axis card and another stepper motor and hooked them up as my 4th Axis and I use Mach2 and Mach3 along with their Lazy Cam. Lazy Cam writes the G-Code from my Cad Drawings in DXF. Every once in a great while, I will have to wrire some code or change some.

There are tons of CNC gear and programs out there. Do careful research for just what you need before biting the bullet. Good luck on that endeavor.

Ray