what about HAAS? good machine?
what about HAAS? good machine?
(OP)
My company is looking for a new vertical machinig center. One of the candidates is a HAAS machine. But I've read about some people having problems with them, a lot of repairs, not able to work 24 hours at day, etc. I'd like to read more opinions prior to take a decision.





RE: what about HAAS? good machine?
This Haas VF2 with less than 100 hours of use had over twice the deflection of any other machine tested, with .0005 movement with 50 lbs of tangential load in any direction. This translates into .001 out of roundness on any circular interpolation with more than 2hp or 50 lbs force when cutting.
RE: what about HAAS? good machine?
That looks like a pretty ingenous way of testing the spindle stiffiness. Did you speak with Haas factory about the results?
I have also heard many not so kind things about Haas spindles. Remarks to the effect that they are disposable items.
It may be worthwhile to steer clear.......
RE: what about HAAS? good machine?
Neither, Haas or the dealer Selway showed any interest in fixing the problem, so I wrote the machine, the manufacture and the dealer off as people to avoid if at all possible for other machines.
RE: what about HAAS? good machine?
Applying a load several inches from the face of the spindle also tests the tooling and interface stiffness as well as the spindle stiffness. Overhang built into the spindle (with the bearings moved back from the spindle face) clobbers the stiffness. Tool overhang can clobber the stiffness even faster.
Your test rig looks to be testing the combined system stiffness of the entire machine. If it has a rubber lead screw that large deflection will be added right in. Not that system stiffness isn't real important. A grounded reference to the spindle housing helps isolate the spindle shaft/bearing stiffness, when that is the desired information.
I was just thinking that real Uniform radial or tangential stiffness would show up as diameter variation, not out-of-round. I would expect the spindle shaft/bearing radial stiffness to be fairly uniform, but the housing/column/table/?? stiffness to be hugely different X/Y/Z.
RE: what about HAAS? good machine?
This tools design is to compare one machine to another, in what would simulate a difficult cutting condition. The part that clamps to the bed is tall, and the cutter long to amplify weakness.
We can apply and measure loads to 500 lbs.
There are several things to change if a person is going to use the tool for actual measurements of individual elements of a machine.
1. The dial indicator should be replaced with a scale to connect to a data collection system.
2. A 3 dimensional laser measuring system would be connected to a separate target on the part of the machine in question to see the direction of movement as different loads are applied.
3. The pillow block bearing and the main pivot bearings replaced with precision angular contact bearings.
4. All parts precision ground square and flat.
5. A circular interpolation done at each load to observe deflection differences as directions of axis drives change. I personally think this would surprise most people, electric drives have poor stiffness when a load is applied to the ball screw.
As to the tool interface stiffness, the only testing done has been with quick change tooling. There is more information on Thread281-80549
RE: what about HAAS? good machine?
Richard Leu
Cascade engineering and Service
Richard_Leu@hotmail.com
RE: what about HAAS? good machine?
RE: what about HAAS? good machine?
RE: what about HAAS? good machine?
RE: what about HAAS? good machine?
I did not say you can not use a Haas, we have been running 1 for 3 years. If you are running plastic, or other soft materials, or are doing low power requirement machining they may well be a cost effective machine to operate. We do small lot quantity (1 to 10 pc.), in some cases the amount of material removed is more than is left. When doing low volume parts we can not spend a lot of time playing with tooling and programming 2 or 3 time as many cuts to do the part, it doesn’t pay.
If you are running 24/7 these are high volume parts and you can spend the time to optimize the process, but it might pay to look at a good make of HMC. Some times the through put of one machine and 1 operator may be less than several machines and several operators.
RE: what about HAAS? good machine?
http://www.practicalmachinist.com/ubb/Forum13/HTML/000551.html
Manufacturing Freeware and Shareware
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RE: what about HAAS? good machine?
http://www.practicalmachinist.com/ubb/Forum13/HTML/000574.html
Manufacturing Freeware and Shareware
http://mrainey.freeservers.com
RE: what about HAAS? good machine?
I guess my point is that these machines are 20hp 40 taper machines. They are also as simple to program as it gets. I also prefer a Mazak but don't knock the HAAS. Just because we run 24\7 doesn't mean that we never do set-up's or write programs. We do! These machines are not table routers for machining plastic. They do get the job done. This of course is my opinion. You have the right to have your own. Have a nice day.
RE: what about HAAS? good machine?
Our company has 6 Haas VMCs. We run everthing from plastic to titanium, but mostly high strength steels. I won't tell you it's the best machine out there, but I can tell you we rip up a lot of metal and (with the right end mills) we can hold some tight tolerances.