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Face or turn?

Before I had a CNC lathe, I used to purchase these. Now that I am turning them myself, I'm learning things.
The part finishes at 1.06 wide. I ordered 1-1/4" long pucks to make them since I can't material handle a bar of that diameter into my saw. I received the pucks and they were consistently sawn at 1.375-1.400.
So that is how I ended up with so much material.


I have had it where it was assumed the 1.25" overall length was going to be my finished length, so the guys cutting the stock for me added some extra.You may need to be more specific in the future.
 
Execute some distance with some feedrate with a single G01.
Now, divide the same distance into 1000 parts, and use 1000 G01 for each segment, using the same feedrate. May use incremental mode, in a loop, for convenience.
The cycle time in the second case would be more.
Of course, block-processing time also comes into the picture, but the major cause is acceleration/deceleration.
Thought so.
 
Execute some distance with some feedrate with a single G01.
Now, divide the same distance into 1000 parts, and use 1000 G01 for each segment, using the same feedrate. May use incremental mode, in a loop, for convenience.
The cycle time in the second case would be more.
Of course, block-processing time also comes into the picture, but the major cause is acceleration/deceleration.
You've got to be kidding. This is about four pases down the face or six or seven the short way. No big deal, either way he'd be done with the parts long before he could get off playing with his dick like this.

No, block processing time does not come into the picture, it's a lathe. 4" part out of hardish 4140, the machine can keep up with whatever you ask.
 
When I said that the cycle time would slightly increase, it was a theoretical statement. It may not be noticeable in usual cases, but can be observed in extreme cases. It is all because of acceleration/deceleration associated with each start/stop. One may conduct the suggested experiment to see this.

And, every CNC, whether lathe, mill or whatever, has a block-processing time.
 
I have a part made from HT 4140. 4-1/4" dia. After working the front, the part is flipped and all extra material needs to come off.

That is about 0.350 in Z and from 4-1/4" down to 1.18 hole thru the middle.

So, should I take multiple facing cuts down to center line, or take short OD turning steps down to size?

This is a larger part than I normally make, yeah yeah, and I wasn't real happy with chip control on facing, but maybe that was just my insert.

So how would you guys do that?
What is the OAL of the part and how much are you chucking on to do the second side? Any parallelism requirements?
 
Execute some distance with some feedrate with a single G01.
Now, divide the same distance into 1000 parts, and use 1000 G01 for each segment, using the same feedrate. May use incremental mode, in a loop, for convenience.
The cycle time in the second case would be more.
Of course, block-processing time also comes into the picture, but the major cause is acceleration/deceleration.
I am fully aware of this. I have used a similar situation to show the difference between Haas and other lathes to show my bosses how slow Haas are even when programmed to the same feed rate.
 
The part is held in Aluminum soft jaws on a 6" Chuck. The jaws are bored out to .550" deep. The part gets faced off and a keyway cut thru the bore in this operation.
Material is 4140 HT to about 30HRc.
The part is saw cut 1.30-1.40" long, first opp. is taking minimum off the front to clean up, drill and bore.
I'm only holding onto about 0.15" for the first opp but since not taking much facing that is fine.
 
The part is held in Aluminum soft jaws on a 6" Chuck. The jaws are bored out to .550" deep. The part gets faced off and a keyway cut thru the bore in this operation.
Material is 4140 HT to about 30HRc.
The part is saw cut 1.30-1.40" long, first opp. is taking minimum off the front to clean up, drill and bore.
I'm only holding onto about 0.15" for the first opp but since not taking much facing that is fine.
I prefer to face this kind of part rather than turn it. It’s faster, and as was noted by a previous post, using the 100 degree corner is an option I use all the time leaving .005 on the face. Index to your normal CNMG turning tool, G0 X1.5Z0. G1G42Z0.F.0097;G76X4.xxx L-.02; X4.xxx+.002Z-.07;G40X4.25F.05; G00 home;
 
Face turn? Is there any way to orient the tool to turn the face with it at around 45 degrees ish in the cut? I could do it on my manual lathe just fine with my rotating tool post. Or get the tool that SeymourDumore posted if you have enough parts to do. Still I would rather have the cutting edge engaging the part closer to 45 degrees vs 10.
 








 
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