Haas UMC-750, tools vary .006 from beginning to end of day.

[5AXIS505]

Does anyone else experience this with their Haas, I know they vary a bit but this seems absurd.  

[#Rekd™]

Are you doing a spindle and axis warmup before measuring your tools and offsets? 

[Kalibre]

Only time I've run into something like that was from the thermal comp being jacked.

It's that or your shop is getting 850F warmer during the shift.

[crazy^millman]

31 minutes ago, Kalibre said:

Only time I've run into something like that was from the thermal comp being jacked.

It's that or your shop is getting 850F warmer during the shift.

you mean 85 degrees not 850 degrees ?

[Kalibre]

14 minutes ago, crazy^millman said:

you mean 85 degrees not 850 degrees ?

Being low on coffee, and lazy I went with .00015"/1"/20F. New super small spindle cartridge?  

[cruzila]

I ran an extended Z VF-8 on a critical boring part in the winter. I did tests on the casting temps, coolant tank temps, shop temps. The biggest deviation I saw was .002 when we turned off the heater at night.

[gcode]

6 minutes ago, cruzila said:

I ran an extended Z VF-8 on a critical boring part in the winter. I did tests on the casting temps, coolant tank temps, shop temps. The biggest deviation I saw was .002 when we turned off the heater at night.

Yes, but the duct tape, bailing wire and chewing gum holding those UMC-750's together is highly susceptible to thermal expansion and compression. 

[#Rekd™]

35 minutes ago, gcode said:

Yes, but the duct tape, bailing wire and chewing gum holding those UMC-750's together is highly susceptible

I think it is wet carboard.....  

[gcode]

42 minutes ago, #Rekd™ said:

I think it is wet carboard.....  

wet cardboard is the deluxe upgrade

[Matthew Hajicek - Singularity]

Since the spindle is cantilevered out so far, if the front of the column gets warmer than the back, or asymmetric heating of certain other members takes palce, it will arch and lift the tool much more than the linear thermal expansion rate.  This problem plagues the whole UMC line, in combination with poorly done thermal comp software.  To fix it with thermal comp, they would have to add a bunch more thermocouples in several locations, and have a much more complicated compensation model.  What I've heard works best on these machines is to turn off the thermal comp, and take every measure you can to keep the temperature of the machine constant within a very small window.

For comparison, I get less than .001" Z change over 20°F on my CM-1's.

[Matthew Hajicek - Singularity]

The alternative is to reprobe frequently, up to every toolchange or even every cut if the tolerances require it.

[Zoffen]

Seems like its in spec. No problem here...

[gcode]

On 4/13/2024 at 6:54 PM, Zoffen said:

Seems like its in spec. No problem here...

 

Harsh, but true

[mwc815]

Make a warmup program with alot of Z moves to go along with the X and Y. Also gradually increase the spindle speed as it runs. Mine takes about 20 min to run and helps  quite a bit.

  Mike

[riverhunter]

I purchased a new 2014 UMC.  it was pretty accurate ( for a haas ).  on a few parts that had concentric bosses 180 deg apart we did have to use the probe to locally set the work coordinates in order to hold a .001 tolerance.  for anything +/-.005 or greater it was a really good machine.  one weird thing is once in a while we did ridged tap when a thread mill was not on hand.  it made the worst grinding sound you ever heard.  other than that, that machine made me a lot of money over the years.  

[gcode]

25 minutes ago, riverhunter said:

it made the worst grinding sound you ever heard. 

That's perfectly normal  LOL

 

serious though, back in the day I was part owner of a small shop

We had 2 Hass VF1's with 5C collet indexers.. 

We made boatloads of money with those 2 machines.

[riverhunter]

35 minutes ago, gcode said:

That's perfectly normal  LOL

 

serious though, back in the day I was part owner of a small shop

We had 2 Hass VF1's with 5C collet indexers.. 

We made boatloads of money with those 2 machines.

 

Had Haas out the first time it made that noise.  the reply was a perfect HAAS response "oh, its fine, it will go away with a software update" that sound never went away

[gcode]

2 minutes ago, riverhunter said:

 

Had Haas out the first time it made that noise.  the reply was a perfect HAAS response "oh, its fine, it will go away with a software update" that sound never went away

even after the spindle caught fire??? 

[riverhunter]

41 minutes ago, gcode said:

We had 2 Hass VF1's with 5C collet indexers.

Yeah, both my VF-4's had rotarys with Lang face plates and tombstones.  it was like having two little horizontals.  bummer was only 50 tools so resident was 1-20 and rest were specials.  they were also very productive little machines.  my st-30 was the one bad investment.  im not much of a lathe guy so i only bought it to prevent  subbing out the little turning work we got.