Originally Posted by JohnnyTurn  Work shift does not need to be used at all. If it is used, it's only used on the Z Axis. |
You would screw yourself real quick if you started moving the X workshift.
Originally Posted by JohnnyTurn Here is a good use of the workshift:
Running a chucking job and through the day you need to adjust for length control. You don't need to move the facing tool in. Just move the Z work shift in the minus for less stock removal and plus for more. This way you do a GRID SHIFT of the Absolute Coordinate System and all your tools move in/out the same amount. |
Changing the workshift gives the same result.
Originally Posted by JohnnyTurn Don't try the novice method of wear offset times 6 tools in the Z to get this result. For some reason, it does not work. |
Why doesn't it? What would be the difference between moving the workshift .006 and moving every tool by .006? However, I agree with you 100% on this. Dumb to stand there and offset 12 stations when making one change to the workshift is all that is needed. Definitely less chance of making a typing error.
Originally Posted by JohnnyTurn NEVER MOVE THE X WORK SHIFT. |
See above comment.
Originally Posted by JohnnyTurn Also the Z work shift is great for running families of parts that only have a difference in the length. If there is enough of the stock sticking out, you just need to enter the amount of shift and make sure you maintain your clearances.
Don't use the Work Shift the way Hardinge tells you to. It's not needed at all. |
Gee. It's been so long since I've looked at a manual for this type of thing that I haven't the foggiest idea how Hardinge manuals tell you to set the workshift.
Originally Posted by JohnnyTurn If using a puller:
Cut off, leaving .250 sticking out of the collet/chuck
Pull to desired length
Face/Qualify/Rough Turn the diameter (this creates your Z0.0 for subsequent tools)
Touch off any remaining tools to this face.
Use wear offsets to dial in the part after taking .0005 face cuts with boring bars and such. |
Obviously you don't have probes (or ignore them). Some of our lathes have them, some don't. Almost all of our lathes are barfeeds. Let me see if I understand you correctly. A 3/4 inch 80 deg. profiling tool has an F value of 1.0. Using a probe would give you a Z-GEOM of .25 (give or take a few thousandths. As I understand it you are leaving the workshift at Z0 so your geometry is going to read in the inches...varying all over the place depending on the part length.
What do you do for the next job? Reset all your tools? Figure out the difference in Z between the last job and the current one, and then make a grid shift? If using new jaws, how do you take into consideration the difference on how deep the jaws were bored for this job versus the last one? How close are you after all this mathematical manipulation? Seems like it could get more complicated than necessary.
Originally Posted by JohnnyTurn That's it. I run super precision parts like this all the time. Work shift is best used for length control. You do not need to use it at all in the program. Someone tell me where the benifit is in using it?
JT |
Okay here's the benefit. I determined after setting up the first job on one of our Daewoo Lynx lathes that I could use 6.8 for my constant. This leaves approximately 1/4 inch sticking out of the collet after cut-off. Now all I do is add 6.8 to my cut-off position (and round off to nearest .01).
We run lots of end washers. Usually make 5 per barstop. Do you want to trust your operators/set-up men to figure out where the last cut-off position will be, and then to extend the bar the correct amount before setting Z0? I don't. They never have to worry about setting a workshift because I do it for them in the program.
There is more than one way for them to set new tools once the Barstop Op has been run. One operator always figured .02 coming off the face and set the tool geometry accordingly. I prefer to MDI my rough turning tool to a known position, face and then set my new tools.
I don't set the workshift on chuck jobs. The set-up guy better be capable of that or he won't be working for us long. At least not as set-up man.
Now I am not saying your way isn't any good, or that it is wrong. Like my Pappy use to say, "There's more than one way to skin a cat."
However, I think I will stick with my way, unless you can show me where I erred in my thinking regarding how you make your adjustments from job to job. AND that it is easier and faster than my way.
EDIT: Sorry JT, but this is bugging me. Still racking my brain trying to figure out how you are going from job to job without having to re-touch all the tools. Arrrrrh. What am I not understanding?
Please explain.