Guys running CNCs..What type of machine do you have?

J

J S Machine

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Oct 15, 2007
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I've decided that the only way I'm going to get to the level I want to be at is by going CNC. I program and run them for a living, but I don't have one at home.

I do have a Little Machine Shop 3900 High Torque Mini mill - the one with the longer travel in all the axes and belt drive head. I have considered converting this to CNC. It would be a lot of work and probably cost me about $1k by the time I was done with it, but I can probably swing $1k a whole lot easier than I can a more significant amount. My concerns are whether or not the little mini mill will be capable enough to do decent work. I don't want to invest $1k on something that isn't going to work for me that well.

Les George recommended Tormach. Those look like some nice machines. I don't need anything big...just a mill with enough travel to do the average sized knife..like maybe 12-14" travel in X, 6-8" travel in Y, and whatever in Z would be ok. Of course bigger would be nice, but if it keeps the cost down that size would be fine.

Any suggestions? What are you guys using?
 
It really depends on what you're going to do with it. I can't imagine your LMS ever being reliable enough to be more productive than working by hand. It will either be painfully unreliable or painfully slow.

A tormach is a happy medium, and can even be efficient enough for moderate production. Novakon makes similar machines at similar prices. In general, they offer a bit more bang for the buck, but tormach makes up for it in reliable support, and currently have the advantage in available accessories.

A fully optioned Tormach isn't far off from the base price of a Haas mini mill, though..
 
I had to completely rebuild the LMS machine to get it up to par. I went in and stoned all surfaces, deburred everything, and shimmed the rack. Also had to shim the column where it mates to the base because it wasn't square from the factory. The machine is in better condition than about 99% of them you would find in use..I'd be willing to bet that. As far as it being slow with a conversion, that's okay for the time being. Just as long as I can depend on it to do decent work for a while, I think it may be worth it. For tactical folders, or any knife that I want to build with numerous parts, I need repeatability. It's just very difficult to get that when cutting every piece with a band saw and grinding by hand.

I would love to have something like a Tormach, but I just don't have that kind of money laying around. I'd have to take out a loan to get it. I know that it would be the best option, but I have two small kids at home and I have to worry about them first.
 
Based on the pictures, I'm going to assume that LMS mill is based off the Sieg x2. You'd probably have better luck stepping up to something based off the x3, or even better the sx3. The sx3 is belt driven so it's a lot quieter and has a lot higher torque. That is what I built my cnc conversion off of. I'm pretty happy with it. However like JS said, these little mills have issues right out of the box. Mine was a pretty good one, even so I had to make a new Z gib for it, which is no easy task. Luckily I work at a machine shop so I knew the right people to get lessons from for that. Also access to the right tools of course.

Anyway, like I said, I'm pretty happy with my SX3 conversion. I use it mainly for making scales, no actual knives for me yet, but for that it does very well.

Also, take into consideration what you want to use to drive the machine. I'm using mach3 and I think it's pretty nice. Very easy to use, has a lot of neat features. Also figure the cost of cam software and tooling, it starts to add up.
 
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i have a mini mill an dnow a bridgeport and cant even think about a CNC that is smaller then the t0ormach. might in the early makig if you are thinkign CNC parts to have the parts making outsourced till you can buy a more proper CNC

water jetters and smaller CNC shops will take on small runs for a cost and i bet you save $$ by having your own cad files for them (lets you learn one step at a time writing code )
 
Is it possible to make them after-hours at your work? Could you ask your boss about renting machine time?
 
I'm using an old slow (early 90's) VMC for my big mill and a new minimill for my small mill.

A lot of makers use the Haas minimill or their toolroom mills. Having used the Haas mini in the past I decided to spend just a little more and went for the Romi D400 minimill which doesn't have the problem with the tool change height so close to the workpiece and it's almost twice as beefy. It's a 12X16 machine that weighs about 6,200 lbs.

When I got started with CNC, like most folks I started with a CNC knee mill. These will do CNC work and they're not a bad place to start, but really you want a proper bed mill to take advantage of the speed, power and accuracy that CNC makes possible. If possible, find something with a Fanuc controller. They're less flaky and more durable.

My favorite CNC when I was first starting out was a dynamyte 4400 VMC with a PCNC retrofit. It was pretty intuitive and relatively inexpensive so it was a great way to learn without jumping head first into a major investment. And at under 7' and less than 4,000 lbs it was pretty easy to move around and fit under a garage door. Its travels were only 9X14 so it couldn't do large work but it was awesome for knife making. It did the majority of the work on this dagger: http://i566.photobucket.com/albums/ss107/Nathan_the_Machinist/carothers_dagger.jpg~original

Unless you're a big outfit or a real machine shop with employees and overhead and need to start cranking out $500/day/machine, a PCNC retrofit is a pretty good way to start in CNC. Avoid the thinking error that you can put a retrofit on a manual machine and save money, it's a fools errand. Either start with a working machine or put a retrofit on an old CNC with a bad controller on it. Converting manual machine to CNC is like putting a Chevy small block into a wagon. It may work, but by the time it works properly you could have bought something much better for less.
 
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