Value of probes in CNC mills?

[RJT]

If all my toolmakers (not operators) are long time users of edge finders and indicators, and are proficient using them, what advantage is a probe? We have all the measuring tools we need to measure parts, so I don't see why we would scan to measure. The only scenario I can see is if we had castings that we had to center up bore or features for each part, but we don't do any of that kind of work. What are some real world examples of how the are faster / better than someone who uses an indicator efficiently?

 

[DavidScott]

I started out as a mold maker and have been using my indicators and edge finder solely for the last 30 years. I just got a new mill with a probe and tool setter, the first of either for me, and would now hate to have to go back. The idea of the battery in the probe dying and having to do it the "old way" for a few days now scares me. It is sooo much faster and easier.

If you are doing just a few parts it is so easy to have a short program that probes the parts then runs your program, no need for a stop. Probe to the center of your parts and how much stock you have is now irrelevant for the first op.

 

[Booze Daily]

I do a lot of repeat work so I add the complete probing
routine to the program after the M30. Next time I just go to the end of the program, jog over the corner and push cycle start. Boom. Done.

I guarantee I can probe a bore or OD faster than I could pick it up with an indicator.

My mills are 4 axis and I have a macro that will calculate WCS at any angle based off a probed location. Probing code is also added at the end of the program. Probe one corner, run macro, have calculated WCS at any A needed.

Only limited by your creativity.

 

[GiroDyno]

Do you program in CAM or long hand?
You might be able to manually find an edge in less time than I can hand code the probe cycle, but by the time you had set up the edge finder I was already a couple minutes ahead of you... because while you were tramming in the vise I just tossed mine on the table and added an extra line in my probe cycle to comp a G68 rotation offset.
I only recently started to incorporate in-process inspection and automatic tool comp cycles, so I'm sure there are some limitations... but so far they have helped take the edge off when pressing the go button on weird one-off and no-second-chance type parts.

 

[mhajicek]

A modern machine should have menu driven probing, no need to hand code a probing cycle. As others have said, it's so much faster, and less error prone, than manual pickup. I'll throw a piece of stock in the vise and have it picked up top/center in about 30-60 seconds. I can be setting up the first tool in a holder while the probe is running.

 

[Larry Dickman]

kind of like asking, what's the advantage of a forklift over a horse and some logs.