Trouble checking "small" holes.

[BANDY]

I work on a Zeiss Eclipse with ST3 trigger probe head, and I have a **** of a time measuring holes that smaller then 0.300 inches in diameter. I usually use a light (probably made out of steel) and short probe (60mm long) with 2-3 mm ruby head. The probe just can't seems to get a reading, and when it doesn't it backs away and keep trying to get the measurement. Problem happens when its backs away way to far and hit the other side of the hole, even pops out of the hole if the hole too small. I have to do lots of pilot holes and I need to do them manually and it takes way too long time this way, and programming became useless. The 30 minute job takes me 2 hour long, good thing I my boss understand what is going on. I had a problem with my probe head and I just got it replaced a week ago, so I am was surprise to see the problem measuring holes still exist. Changing the prehit -retract distance under parameters settings doesn't change anything when it has a problem measuring the hole. Maybe my probe is too light and it needs to be heavier? Anyone got an idea?

PC-DMIS CAD 4.0

[JamesMannes]

I don't know how 4.0 works for you, but I skipped 4.0 and 4.1 and use a beta of 4.2. How about turning on "find hole" that should do it.

[PingBoy]

If it's anything like the old ST probehead, it has to do with the kinemetic energy not getting to the piezo sensor. There are a couple of things you can do.
1. Use a stiffer probe (carbide)
2. Use an extension between the probe and the adapter plate.
3. Increase the probing speed.

Hope this helps...

[BANDY]

How do I change the measuring force ? Also can anyone recommend a probe for holes dia around 0.100. What do you use?

[bw_bob]

How do I change the measuring force ? Also can anyone recommend a probe for holes dia around 0.100. What do you use?

Measuring force ???the force it takes to set off the probe or speed it takes hits.

On a .100" hole all you can use is up to .078 (2mm) size probe anyway. I always look at what i need to measure and go from there.

[jkb_mcg]

I agree with Bob...I use like a 1mm or 1.5mm probe about all the time. Also, as James said, you should turn the Find Hole option on and it should work. Be sure to set your check distance. That's also found with retract and retract settings. Be sure you have all zero's in the boxes above # of hits, unless you really want to sample the plane the hole lies in.

[BANDY]

I did all that was described above, it is a little better, but still doesn't work. I need take over and do it manually. It seems that I need to hit it pretty hard to register as a measurement. I just don't understand why it is only doing it in holes. I am going to buy some carbide probes see if that helps. If it doesn't then I have to accept it as the limitation of the machine. (Or mine)

[PingBoy]

Bandy,

I don't get on here much so this is kinda late but the carbide probe should help out. I used to run the ST head all of the time and I think it is same as what you are using in that it has an electronic sensor much like TP200.
If this is the case, flexible (i.e. steel) probes are a problem, especially in small holes. I also usually used a 1.5mm for most work. The one I found works best was a taper probe that was about 80mm long. The other thing that helps is to put one of those 10mm diameter extensions between the adapter plate and the probe you are using. The longer the better.

Of course, if you don't have electronic trigger, disregard everything I said...