Global S Chrome temp range?

[tami_]

Good morning,

This really isn't a PC-DMIS question although if anything in P-DMIS could help in this situation like how well the temp comp works, input would be appreciated.

We just bought a new Global S Chrome and they installed it on the work floor in our new building (running Swiss and 5-axis machines for small medical devices). I thought they were going to build a climate control room around it and was surprised the salesman had convinced the people in charge of this project that a box around the working area granite (open on the front side) would be sufficient. I was under the impression that even these best of the Global S machines required climate control to keep the working box 68°F +/- 1.8°F in order to maintain precise measurements. We went through all the documentation provided with it (which only included the blue and green stats to tell the truth) and found nothing that would provide this machine the ability to work on a working shop floor, even a climate controlled one like is used in medical device industry due to heat fluctuations of the working CNCs.

It does have the PULSE package with it. Anyone have any experience with that? As far as I can it will help.

I am worried at the moment that we are going to be fighting to meet the tolerancing of the parts in this situation though.

Thanks for any input.

[JEFMAN]

Here, pages 10 &11 :

https://tbvn.com.vn/upload/catalog/Hexagon-MI-GLOBALS-Datasheet-APAC-rel3-min.pdf

[tami_]

Here, pages 10 &11 :
https://tbvn.com.vn/upload/catalog/H...C-rel3-min.pdf

Awesome … just what I needed but not what they provided! Looks like PULSE will do a good job letting us know if there are any environmental issues too!

[louisd]

So the S chrome we just bought a year ago was quoted with Fabreeka vibration isolation.
Don't EVER accept this configuration. It equates to a slow lemon. Hopefully sales learned a lesson, that these two don't mix.
Our 8 year old Global Advantage at 80%, is faster than this Global S chrome running at 100% speeds.
If vibration is an issue, you are entirely SOL on keeping that machine performing as advertised if you need to mitigate vibration using active fabreeka system.

The advertised accel parameter on the S chrome is 5000, with Fabreeka installed, it HAD to be brought down to 500, to enable the machine to even be capable of executing the laser map and calibration.
It has to do with the spring-packs on each axis drive-belt mount, (which is what makes the S Chrome unique to the blue and green). The dwell time it takes for the machine to settle/stop moving once it moves to a coordinate location, moving for upwards of 9 seconds, would time-out the calibration process and fail as a result.

Re: temp comp and pulse:
The machine is advertised to meet spec within a temp range of 18-22°c. There's extended specs which are 16-26°c.
Our machine is certified to the extended spec, and typically sees 3-5°c variation every day (towards upper limit). It still repeats on our small product (largest sample is maybe 6" long) with variation in the 20-40 millionths of an inch (0.00002" - 0.00004") which is absolutely amazing. We produce injection molded plastics, so this is more than we will ever need for accuracy.

When you load a routine, there's a TEMPCOMP command you can insert at the beginning. There are TCOE material options pre-loaded, and you can customize them as well. Put the magnetic temp probe on the sample (or fixture), let soak, measure.

[Rondog]

...
The advertised accel parameter on the S chrome is 5000, with Fabreeka installed, it HAD to be brought down to 500, to enable the machine to even be capable of executing the laser map and calibration.
It has to do with the spring-packs on each axis drive-belt mount, (which is what makes the S Chrome unique to the blue and green). The dwell time it takes for the machine to settle/stop moving once it moves to a coordinate location, moving for upwards of 9 seconds, would time-out the calibration process and fail as a result....

I don't think the vibration system is the problem. Maybe the setup of the laser perhaps during data collection (You cannot have the laser mounted off the machine table). I have seen some machines take a long time to move to final position when collecting data with a laser. I don't know why there is a select few machines that does this but it does exist. I have a method to deal with this as I couldn't find a solution to stop it from happening by the way.

With a good vibration system the machine will move quite a bit but I have never seen it affect measurement accuracy or speed in a negative way.

[Peter Fuller]

I don't think the vibration system is the problem. Maybe the setup of the laser perhaps during data collection (You cannot have the laser mounted off the machine table). I have seen some machines take a long time to move to final position when collecting data with a laser. I don't know why there is a select few machines that does this but it does exist. I have a method to deal with this as I couldn't find a solution to stop it from happening by the way.

With a good vibration system the machine will move quite a bit but I have never seen it affect measurement accuracy or speed in a negative way.

+1 Fabreeka systems are fun when setting up lasers. But shouldn't be an issue for accuracy.

[louisd]

Peter, if you'd love to look into it, I'll share the unit's S/N with you (PM me).
First qualification attempt by Crist Felde failed (using Koba step bars) due to the high dwell rates.
Second qualification attempt by Matt Johnson was successful, but by skin of teeth (using laser, with laser mounted to granite from what I recall).
Accuracy wasn't ever an issue during the failed qualification, it was the time it took for the machine to stabilize.

Apparently, the story I received from Matt Johnson was that when Hexagon acquired DEA in Italy (Global S Chrome designers) there were some communication barriers for the installation instruction and guidelines. DEA said if Fabreeka is absolutely required, it is mandatory for the accel parameter to be limited at 500. Hexagon didn't know until they already delivered our unit.