Problem- SHAME ON HAAS!!!!!!!!!!!!!!!!

[Maechler]

SHAME ON HAAS!!
Just bought a new EC 1600 with a full 4th in the table. This thing cost around $250K and you would expect to get something that would at least work as good as our $70k fadals. I would not tell anyone that wanted to hold under .002 (yes .002 not .0002) on the rotary to buy one. The factory tech even came in and tells me that is just the way it is, you will have to go past the postion in one direction and then come back to it in the other direction taking out the backlash. We have 25 cnc machines with 4th axis and not a single one of them has that much backlash, or at least a way to adjust it out. We have a 1983 toshiba that is not this bad. Can not even begin to tell what a dissapointment this machine is. SHAME ON YOU HAAS.. why would you even make a machine in this day and age that would not hold .002????

[locash]

You need to call the factory in Oxnard and escalate this issue. Asking it to hold .002 is not asking for much, and I would be pissed too.

Call the 805-278-1800 number and try to get someone who knows something.

[Maechler]

There is a factory man from Oxnard here now, his is the one telling me that I will have to go past the postion and back to it to remove the backlash in the rotory.

[l u k e]

What are the advertised specifications?

[Machineit]

I can understand your frustration, but it's time to stop ranting and just deal with the issue. Posting here does not deal with the issue very effectively, unless your intention is just to bash Haas. No company is perfect and no piece of equipment is perfect. Overall, those of us who have our Haas machines are very happy.

I do not know what the spec's are on the built in rotary in your machine, but I looked up the spec's for an HRT210 and it was 30 arc-sec of backlash. That does not seem like much, but it is 120th of an arch minute or .0083 degrees.

Over the 28 inches you say you are trying machine, that equals .0041" of deviation. Then you can add on the accuracy and repeatability of the unit. It makes sense to me to do as recommended and remove the backlash with the procedure recommended.

On the ways of the machines the recirculating ball nuts can take the pressure because they are always rolling and not rubbing, but on a rotary axis the is always rubbing between the worm and the gear. If you make the pressure too great, in order to remove the backlash, the gears will fail. Then of course you have other connections between the encoder and the actual table surface.

I hope that you get the issue resolved, but I think that setting it up by dialing it in and setting the A axis and not some parameter would be more accurate and repeatable.

Best of luck with your issue.

Mike

[DRD]

I have to say, getting on the interent and bashing a company is about the standard today. You never hear anything good about a company , just that bad. If peoples attitudes were better, you would be amazed at the help they would get.

Anyways, we own a trunion table from haas. The rotary specs are about the same as what you have. We use the table to machine cylinder head ports, 5 axis motion, very comlex stuff, probally alot more complex than most users would ever perform. The table was not repeating since day one, we had problems with the 2 machined ports not linning up, machined from opposite sides.
After looking the problem for a very long time, we took it upon ours selfs to fix the problem. We had talked to haas on the issue, and they had gave us some insite. The table specs were what they claim. Real life use is, you have fixtures and maas on the table, the alters the repeatablility. The is a comp table in the control, were you can adjust the comp on the table. After some trial and error testing, we were able to get the table 100% dialed in.
The Hass is very nice machine, nothing is perfect out of the box.
Good luck.

[Maechler]

I can understand your frustration, but it's time to stop ranting and just deal with the issue. Posting here does not deal with the issue very effectively, unless your intention is just to bash Haas. No company is perfect and no piece of equipment is perfect. Overall, those of us who have our Haas machines are very happy.


We have 6 other haas machines and very one of them is fine, they all have a rotary on them and I have no complaints. As for ranting.. you spend $250k for something and dont get what you pay for. And this whole post is to let others know what they might expect can happen to them, Something I wish I had known before now

I do not know what the spec's are on the built in rotary in your machine, but I looked up the spec's for an HRT210 and it was 30 arc-sec of backlash. That does not seem like much, but it is 120th of an arch minute or .0083 degrees.

My parts have to be closer than that, and my 28 year old toshiba will hold it, so why cant the haas

Over the 28 inches you say you are trying machine, that equals .0041" of deviation. Then you can add on the accuracy and repeatability of the unit. It makes sense to me to do as recommended and remove the backlash with the procedure recommended.

On the ways of the machines the recirculating ball nuts can take the pressure because they are always rolling and not rubbing, but on a rotary axis the is always rubbing between the worm and the gear. If you make the pressure too great, in order to remove the backlash, the gears will fail. Then of course you have other connections between the encoder and the actual table surface.

We have 26 rotarys, I know how they work and none of them have this much slop.

I hope that you get the issue resolved, but I think that setting it up by dialing it in and setting the A axis and not some parameter would be more accurate and repeatable.

It will not repeat to within .002

The inspection report that comes in the door of the machine, says it had .0002 at 4 postions 90 degrees apart. Thats what I want everytime. 26 other rotarys of 4 differant makes in this shop can do it!
Best of luck with your issue.

[Maechler]

DRD

I also cnc port, I have a fadal with nikkens rotarys and have not had that problem. Do you use mastercam for porting. Been wondering how well it works, I think I would like that mastercam will let you ramp the paths where they meet from both sides, least thats what it looked like it would do.

[djr76]

Have you tried the reps recommendations?

[Maechler]

Originally Posted by djr76 Have you tried the reps recommendations?

Rep is here doing it himself.

[HuFlungDung]

At what circumference are you expecting to hold this tolerance? Is the minimum arc command still .001 degree on this table/machine combo?

It might have backlash, but I'd be surprised at a lack of repeatability, if the tests are made all from the same direction of rotation. The thrust bearings on the wormshaft may not be properly preloaded? I don't know how you'd test for that, but you'd need super precision bearings and very careful testing and assembly to make it right. One cannot assume that an assembly error of some sort could never happen. It is a matter of determining the source of the error, more than looking at some sort of chart of specifications, to see if any improvement is possible.

[dougtyler]

Isn't this what backlash compensation is for?

If the machine will repeat position, and the amount of slop is always the same, then there is a parameter made specifically to correct the problem.