Suggest a turning center for these parts-

[Milacron]

Moderate production, but goal is to eliminate secondary operations and make these parts with as few employees as possible. I forgot to ask material but presume mild steel on the cam, and SS on the smaller parts.

For sense of scale, threaded end of cam shaft is about 1/2" diameter.

www.practicalmachinist.com/parts3.jpg

Budget unknown but guesstimate $50,000 for used TC if live tooling equipped, less if standard TC.

So really the big question is, can live tool TC be justified here or not, and if so, what might be out there in that budget ?

Ironically I owned and sold a like new live tool, subspindle machine for $48,500 a few months ago (the 1993 Hitachi Seiki CAB65 with all the goodies)..but don't forsee finding another like that 'for stock' anytime soon, so looking for one from another dealer if that's the way to go. But first need to know if that is indeed 'the way to go'

 

[WILLEO6709]

for that money you might be ahead with a small vmc and a simple turning center. The older citizens you see on ebay would fill those parts nicely, but I don't know how much cam profile milling they were capable of. I look forward to reading more responses.

 

[metlmunchr]

Is the crankshaft looking assembly made up of 2 parts or 3? Looks like the main shaft is pressed into the counterweight, but not sure of that. That the crankpin is pressed in is obvious.

If 3 pieces, then the counterweight looks like a mill part to me, and that should substantially reduce the required size of the live tool machine and eliminate the need for a subspindle.

If 2 pieces, then the machine will need to be bigger to make decent time in profiling the counterweight, and I think it would need a subspindle to do the milling unless it could be turned around in the main chuck for access to the big end once the shaft portion is turned.

If the counterweight is a separate part, and would be done on a mill, then, given the simplicity of the milling ops on the other parts, I'd question the need for a live tool lathe at all. One machining center could carry setups for all the parts, and one operator should be able to feed both machines. Of course, whether or not they've already got a machining center would be a deciding factor in this too.

Not an answer.....just some more questions

 

[Boris]

I see no problem with the small lathe /small VMC option path route thing.

Assuming the cam thing is a 2 part item

lathe

turn thread/shaft/major OD of cam, part off

Mill

Locate part in a 3 jaw chuck using custom soft jaws milled/turned to shaft diameter.
Flash over top surface to remove part off finish/pip, Mill profile, drill and ream offset hole.


As for the small hexagonail thing,

turn complete less thread, then place in chuck with another set of soft jaws, and mill hex, then back on lathe in suitable collet and turn thread.

Place the 2 machines facing each other, and operator can run both.

Of course thers always a another way to do stuff but thats my way.

Boris

PS Use cattle prod on operator if he is'nt working hard enough

 

[Milacron]

Cliff, the crankshaft looking thing (what I was calling a cam looking thing) is 3 parts..the cam or counterweight part is press fit on. But maybe they would like to do it as one part...awful lot of material removal if so...could that be cost/time justified at all to try and do from one large round bar or would it pretty much have to be forged to make any sense ?

Also, FWIW, they already have a very nice late model CAT 40, VMC with 30 tool changer.

 

[Mark McGrath]

Everything except the counter weight on a sliding head cnc with driven tooling.Counterweight turned,and crankshaft bore and crankpin bore done and parted off from bar on fixed head cnc with live tooling.Counterweight profiled on VMC using crankshaft and crankpin bores to locate and hold it.Weight could be finished complete on lathe but cycle time would go up due to amount of milling.
Mark.

 

[Ox]

If the crank shaft is 1/2" - then running the big part from solid on a Swiss is outta the question doo to size. (I know they make bigger Swiss these dayz - but not for 50 G's)

If made from many parts - then a Swiss or any smaller live tool machine could run them... well ... are those holes in the top left part on an angle? If so you would need a machine that has an angle cross drill unit available for it. You could be talkin' 6-10 G's for that alone, but would allow you to go back in and deburr the through-hole before you cut it off.

One thing to consider also in making the crank throw on a lathe is the fact that you would need to have your small diameter mills hanging out a long ways to get past the shaft if done on the main spindle. Some have mentioned running the crank throw on the sub - but C axis is not all that popular on most subspindles - especially anything that is in your said budget. And I too would say that it could be done quicker in a VMC. (And I LOVE to run parts complete on the lathe...)


Fetch a hydromax type comp front jaw and stack up 3-4 of them in the 6" Kurt and drive on!


If it were my parts - I would want the crank made as one pc plus the pin. Maybe not the cheapest to make - but a lot better part when finished.


Think Snow Eh!
Ox