Our team has recently acquired some new sponsors (finally!) and they've donated us some CNC equipment and money. It's a Tormach PCNC 1100. We're happy to accept the CNC, but we're not very experienced with it. I have some experience with machining, but that was a long time ago, before CNC machines were common.
Basically, I'm looking for a bit of advice as I wasn't prepared for this, and I have to make some decisions kind of quickly. If anybody has positive or negative experience with the machine (or CNC with FRC in general), please let me know. I'm hoping the tormach will work for us. I HAVE read the previous posts about CNC tooling from Cory, which were very informative.
We're in a bit of a weird situation so we were wondering if anybody had suggestions for how to use the money- we have a CNC mill, but we don't have a normal mill. We do have access to a lathe, and we're happy with that.
What I'd like to do is take a local class on CAM software (I'm thinking MasterCAM, I have some very basic experience...any suggestions?) and spend money on tooling. I've seen the threads on here, and I've got a preliminary list.
T-Slot hold down kit (purchase)
2 nice Kurt vises (given to us)
Coolant (what type??)
Drill chuck for R8
Collet set(.125, .250, .375, .500, .625) sizes
Endmills:
We've been given some spare tooling, but most of it is weird stuff. We've got lots of tiny (<.125") end mills, and some huge stuff, but nothing great. It's mostly carbide stuff.
I'd like to purchase some of the HSS two sided end mills (for when we break them..) from McMaster- just the normal stuff (.125, .250, .375).
We've got the 4th axis, so we're likely to try doing some gear making with involute gear cutters, but we may wait on this purchase for a bit.
It came with a 6" diameter face mill, which may be a bit big. I don't see us having to do too many face milling operations, so I'll probably hold off on purchasing for a while.
I'll also get an edge finder (did you know they make ones that make noise?) and a dial test indicator (the one where the needle rotates instead of going in and out). Has anybody had experience with McMaster's "economy" indicators? They're a lot cheaper than the Brown and Sharpe.... I don't want to get one if it's like their "economy" calipers, which were the worst (Grizzly IIRC) calipers I'd ever seen. I get suspicious of things like
this.
Is this enough for our first year? Our most ambitious plans would include at most doing gearbox plates, multi sized hex shafts on the 4th axis (how do you program this?), putting some lightening/locating features in some thin walled rectangular tube, maybe some type of wheel/roller, pulleys or sprockets, and lightening patterns in steel gears.
My goal is to not spend a bunch on tooling, so if anybody knows places to get this sort of stuff cheap, it would be appreciated.
This may be a really, really dumb question, but if we'd like to save money and not get a probe style indicator, can we just zero the z axis by slowly lowering until we can't slip something thin underneath, then take off the thickness of the thin piece?
My second question deals with the Tormach. What can we cut and how accurately can we do it? The machine looks good, but I am clueless as to what can actually be cut at reasonable speeds. I've been doing some math, and to me, it looks like the limiting factor will be spindle RPM (5100 or 4400 rpm-does anybody know which is correct) for using the .250 endmill. I'm getting values of over 20 inches/min with a .125 deep cut, which seems like a lot, as I'm visualizing trying to do that on a smaller mill. How rigid is the tormach? I think I'll buy GWizard to do the math for me. I'd like to try sprockets (steel and aluminum) eventually. Is this feasible? Also, how accurate can we get a circular hole? I'd love to be able to do bearing bores without needed a reamer.