cnc micro mill

[scubasteve4sq]

Nathan, what do you think of the g0704 for knife steel work? What about the tormach pcnc1100?

 

[Nathan the Machinist]

What's your heaviest machine in your shop Nathan?

Fred

Thee Olde Grey Pig, a 16X30, is pretty close to 9,000. That's a pretty typical mid size 40 taper. Big stuff such as the stout Japanese iron and 20X40 mills, which we don't have, range from about 12,000 -> 20,000.

 

[Nathan the Machinist]

Nathan, what do you think of the g0704 for knife steel work? What about the tormach pcnc1100?

I have no opinion on those, never used one.

 

[Stacy E. Apelt - Bladesmith]

While we are discussing mills for knifemaking, what is your opinion of the Tormach 1100. How much more will be needed to get it up and running in CNC from the $8K advertised price.

 

[Nathan the Machinist]

While we are discussing mills for knifemaking, what is your opinion of the Tormach 1100. How much more will be needed to get it up and running in CNC from the $8K advertised price.

I tooled up a small machining center a few months ago for about $3,500. That included tool holders, collet chucks, drill chucks (25 CAT40 tools in total), Kurt vise etc. This is quite a bit less expensive than people frequently think.

You can get a Kurt vise for $455 and free shipping from Enco if you order from their sales catalog and use code: SAVE20VIP and VIPSHIP

Maritool has high quality tool holders etc at a very good price

So it's not as bad as people think. And you wouldn't need that many tool holders to start, though you will need a good edge finder, parallels, dial test indicator, clamp set etc. So all told, about $3,500 to properly tool up a CNC mill is probably a pretty good guess if starting from scratch. EDIT: you can spend way more that that, but we're talking small scale here. That assumes you already have measuring tools and stuff like a bandsaw etc to feed it.

Eventually you might want a coaxial indicator, a few boring heads and tap heads and perhaps a right angle head etc, but you can get by without these

My first CNC mill got by with just 6 tool holders for years. Chinese vise too (that's usually false economy btw). Wasn't real productive though...

Cutting tools is another thing. You'll eventually want a roughing and finishing facemill and inserts are typically $10-$20 each X ~6 per cutter body. A good Lakeshore Carbide 3/8" stubby endmill is around $18 each. It's not too hard to consume $100/day in carbide.

When you're learning the ropes there is a good application for HSS or import cutting tools, but ultimately it's no different than grinding belts, you know the deal...

 

[Nathan the Machinist]

While we are discussing mills for knifemaking, what is your opinion of the Tormach 1100. How much more will be needed to get it up and running in CNC from the $8K advertised price.

If it were me, I'd rather get a good older CNC mill with an industrial control, but I understand the appeal of a small new CNC.

If I remember right, it's about 1,000 lbs? I expect you could probably do a lot with that. It would certainly be better than nothing.

You could surface mill bevels, but this is slow and consumes a lot of carbide per bevel. Side milling and face milling is much faster, cheaper and gives better results, but it takes a mill with balls to do it right in knife steel. My smaller mills won't do it, only the pig...

If you're profiling blades a smaller mill should do fine. Milling scales too, it doesn't take a lot of grunt to cut micarta. You do need some kind of sump filtration if you're doing much of it, or good dust collection.

It's like buying a car isn't it? You can get a nice BMW pretty cheap if you buy an older one. But then there is the upkeep. Or you can get a new Hyundai.

 

[12345678910]

You'll eventually want a roughing and finishing facemill and inserts are typically $10-$20 each X ~6 per cutter body. .

What's the difference between the roughing and the finishing.

Do you just have two identical tools and inserts, with one designated roughing and the other kept for a finishing pass ?

Or are there different geometries

 

[Nathan the Machinist]

What's the difference between the roughing and the finishing.

Do you just have two identical tools and inserts, with one designated roughing and the other kept for a finishing pass ?

Or are there different geometries

If you're smart (which I'm not) you have a 45 degree insert face mill for roughing, which is durable and removes material smooth and efficient, and then finish with something with a sharp honed edge. In knife steels you want to finish with something sharp and free cutting and without a wiper flat to prevent smearing and distortion.

In practice, I use an antiquated APET 1604 insert design. I use two facemills, one for roughing and another for finishing. I use fresh inserts for the finishing pass and use used inserts for roughing. (to anyone getting into this, I'd recommend something more current, but I use what I got...)

For the best finish, I use a single insert, spun around 500 SFM, fed .004" IPT and .003 DOC, under flood coolant. I'd run ground stock, but I'm engraving my mark and it's better to deck the top then engrave to control depth.