[Xeno]

From my Haas Manual the Alarm is explained as:
"Tool did not release from spindle when commanded. Check air pressure and solenoid circuit breaker CB4. Can also be cause by misadjustment of draw bay assembly."

What happens is the machine wants to change a tool, so the Tool Changer shuttle goes in to get the tool that's in the spindle correctly, the spindle comes down to the proper z level correctly. But when it tries to release the tool it can't so it sits there hissing for a few seconds ant the Alarm #134 "Tool Clamp Fault" comes up.

I have a 1995 Haas VF3 and this has been going on for past 3 weeks but only when the pressure on my compressor is at the low end of it's range (I've always called it a Schmidt trigger but there may be a better term). Its range is around 95 to 120 psi. To work around this I had to get the air pressure up to a higher level. Unfortunately that doesn't even work.

I do have a air pressure regulator on the VF3 which appears to be set at 90psi. In the manual it specifies a minimum of 85psi. I had worse problem that was a higher priority (ended up needing an x axis motor/encoder cable harness) but I thought it may be solved by keeping the pressure higher so I ordered a new pressure switch that would keep the pressure range higher.

In a nutshell, I think the Tool Release piston isn't going down far enough, the limit switch doesn't get triggered so VF3 alarms out after a specified delay.

I hooked up a pressure gauge where the air goes into the Tool Release piston assembly and it's getting 95psi.

How would I trouble shoot the solenoid?
Why would a higher pressure on the compressor side of the regulator let it work for a while? I guess the regulator may not regulate perfectly.
Are there drawings/diagrams posted that I could refer to?

I'm wondering if piston O-rings need replacement. Is this something I can do or should I call a Haas tech to do it?

Any ideas to trouble shoot will be appreciated.
Tony

[Xeno]

I forgot to mention one more issue that may or maynot be related.

When my machine is running, it uses/losses compressed air. I have a 80 gal air tank and while the VF3 is running it'll have to kick on every 15-30 min. I think it also looses more air the faster the spindle turns.

But if the VF3 is turned but not active, it can go hours without my compressor having to turn on.

[Machineit]

Tony,

Two different issues maybe. The tool may be sticking in the spindle, so clean the spindle bore and the tool holder very well and put some sort of lube on them and try it.

When the spindle is running and for a minute or so after it stops, air is sent out around the spindle. Circulates oil and keeps chips out. There is a separate regulator in the rear just for that air. I think it should be set to about 15 psi, but look it up as I don't remember for sure. If this is set too high or is not functioning correctly it will use a lot of air.

Mike

[haastec]

Tony,

Two different issues maybe. The tool may be sticking in the spindle, so clean the spindle bore and the tool holder very well and put some sort of lube on them and try it.

When the spindle is running and for a minute or so after it stops, air is sent out around the spindle. Circulates oil and keeps chips out. There is a separate regulator in the rear just for that air. I think it should be set to about 15 psi, but look it up as I don't remember for sure. If this is set too high or is not functioning correctly it will use a lot of air.

Mike

As pointed out, the most common cause for this is tools sticking in the spindle. Most common causes for this is dirty tapers, excessive heat, or excessive vibration; one or a combination of all can cause your condition.

When you get the alarm, how do you get the tool out of the spindle?

Do you get this problem on one or two specific tools or is it random?

If/when you have the tool out of the spindle, does the tool release sound normal when pressing the button?

Without a tool in spindle, watch the diagnostic bits for the Tool Clamp/Tool Unclamp; do they toggle normally?

[Xeno]

Haastec,

you wrote "... When you get the alarm, how do you get the tool out of the spindle?"
For a month every time this would happen, I'd get the pressure coming from the compressor to be in it's high range. The problem only occured when the incoming air pressure was very low in it's range.

you wrote "... Do you get this problem on one or two specific tools or is it random?"
It seems to be independent of any tool.

Your last two questions I"ll have to check this evening when I'm at the machine.

I did take off the front cover and watched as the tool release tried to toggle the lower limit switch. It barely touches the switch, I assumed it didn't toggle the switch. I'll check diagnostics tonight.

I wonder if a lot crud is up there and it just needs to be cleaned out.
Tony

[Machineit]

Haastec,

you wrote "... When you get the alarm, how do you get the tool out of the spindle?"
For a month every time this would happen, I'd get the pressure coming from the compressor to be in it's high range. The problem only occured when the incoming air pressure was very low in it's range.

you wrote "... Do you get this problem on one or two specific tools or is it random?"
It seems to be independent of any tool.

Your last two questions I"ll have to check this evening when I'm at the machine.

I did take off the front cover and watched as the tool release tried to toggle the lower limit switch. It barely touches the switch, I assumed it didn't toggle the switch. I'll check diagnostics tonight.

I wonder if a lot crud is up there and it just needs to be cleaned out.
Tony

"... When you get the alarm, how do you get the tool out of the spindle?"

What Haastec is asking is if the button is pushed does the tool actually stick in the spindle or does it come out and you still get an alarm? You need to be specific step by step as to what happens.

Also you said, "I did take off the front cover and watched as the tool release tried to toggle the lower limit switch. It barely touches the switch, I assumed it didn't toggle the switch." But, you don't say if the tool comes out or not. The tool can still come out, but not trigger the switch!

Mike

[Xeno]

The tool does not get released, it does not come out.
Tony

[Machineit]

Make sure that the compressor itself has no regulator or is turned up as high as it goes. Then make sure that the hoses used are of sufficient size to allow the air to flow freely. Then make sure the regulator on the machine is turned up too.

You may be getting a drop in pressure when the tool change occurs. You may have 85 psi at the start of the change then it drops as it does not get good airflow. If all you have to do the get the tool out is to wait until the air pressure builds up, then you need to fix air flow and or get a larger compressor. The air pressure required by the Haas is 85 psi, but it also must have sufficient flow also.

Mike

[Xeno]

When the compressor was in the high range...
- I could manually put a tool in and out

In diagnostics,
DB OPN = 0 never changed, even though I could put a tool in and out
DB CLS = 1 in normal state, it does go to 0 when changing a tool


I called Haas tech support in califorina. After talking with him for a while he had me move the lower limit switch, by loosening it's bracket screws which are in a slotted hole about .025 inch closer to the tool release. This worked, the VF3 could change the tool in and out on it's own. I got off the phone with tech support, but when the air compressor went down low again, the machine alamed out, and I couldn't even put a tool in manually.

Note that the Tool release spring is never fully compressed. Also during the delay the air pressure seems to

I think the Tool release piston isn't going down as far as it should, and it keeps getting worse.

[haastec]

When the compressor was in the high range...
- I could manually put a tool in and out

In diagnostics,
DB OPN = 0 never changed, even though I could put a tool in and out
DB CLS = 1 in normal state, it does go to 0 when changing a tool


I called Haas tech support in califorina. After talking with him for a while he had me move the lower limit switch, by loosening it's bracket screws which are in a slotted hole about .025 inch closer to the tool release. This worked, the VF3 could change the tool in and out on it's own. I got off the phone with tech support, but when the air compressor went down low again, the machine alamed out, and I couldn't even put a tool in manually.

Note that the Tool release spring is never fully compressed. Also during the delay the air pressure seems to

I think the Tool release piston isn't going down as far as it should, and it keeps getting worse.

Fix your compressor issues first!!! I can't say that enough; you will be chasing problems until you do so.

I am not saying you do not have other mechanical issues, but you may be seeing symptoms of low air and focusing your attention in the wrong places.

[Machineit]

Fix your compressor issues first!!! I can't say that enough; you will be chasing problems until you do so.

I am not saying you do not have other mechanical issues, but you may be seeing symptoms of low air and focusing your attention in the wrong places.

+1

[Xeno]

The air compressor has no regulator. The regulator attached to the VF3 was set at 90psi. In an attempt so see if it would help up put the regulator up to 95psi but it didn't help. Air pressure going directly into the Tool Release Piston assembly I checked to be 90/95psi. Regarding air flow, the fittings are 1/4 NPT. There may be an air flow problem going into the Tool Release piston as it seems to peter out.

I guess I'd have to keep the pressure gauge on while it's changing a tool?

[tc26]

I looked up the requirements in the mill installation manual.
vf1-vf11, 40 taper, 85psi, 3/8" air line
vf1-vf11, 50 taper, 85psi, 1/2" air line
1/4" line is too small no matter what spindle taper you have.

[tc26]

We had 1/4" supply lines when I started working here.
All have been switched to 3/8" (40 taper, VF2).
The problem you are having happens occasionally, but not as often as it used to with the 1/4" lines.
To release the tool, I place a bundle of rags on the table and lower the spindle down close over the pile.
While holding the tool release button, tap the tool holder with a hammer.

[haastec]

I looked up the requirements in the mill installation manual.
vf1-vf11, 40 taper, 85psi, 3/8" air line
vf1-vf11, 50 taper, 85psi, 1/2" air line
1/4" line is too small no matter what spindle taper you have.

He stated that he was using 1/4"NPT which referres to the thread of the fittings. He did not indicate what the I.D. of his supply line is.

Xeno,

You may very well have a mechanical issue with the tool release piston and/or the drawbar which is preventing the tool release, or possibly something else all together. I guess I keep questioning the air compressor because you keep making note that you only have issues when the compressor gets low on air.

Now if you are telling me that you have adequade air supply at all times going to the machine for both PSI and for volume, then we can scratch that off and move forward. I am just reading mixed information and I am trying to eliminate the easist problems first.

Please clarify some things:
Your compressor is set to cycle between 95 and 120 PSI correct?
Have you verified the pressure reading with a different guage?
When the tool changes (normal cycle) does the compressor ever drop below 95?

If your pressure at the tank never drops below 95PSI at any time during the machine run then the pressure at the compressor tank will not matter whether it is 95, 120, or even 200 because you state that the machine regulator is set at 90PSI.

Now, does the machine regulator ever drop below 85, the recommended setting, especially during a tool change?

Again, if the compressor is supplying good air and the machine never drops below 85 then you can start looking at the tool release piston and drawbar.

[tc26]

Page 2 of the installation manual gives all of the specs and requirements for air supply system.
Also give pressure drop spec at tool change.
It is a must read to solve this problem.

http://www.haascnc.com/doclib/manual...stallation.pdf

[Xeno]

The availability of the compressed air to the Tool Release Piston (TRP) Assembly does seem to be the problem.

I put an air Gauge just before the TRP so I can see the pressure just before the TRP while it's trying to change a tool.

When the 80 gallon compressor tank reads above approximately 95 psi, the TRP works well. And when it works well, the psi just before the TRP reads around 80 psi while it's changing a tool.

When the compressor tank reads somewhere around or below 95psi (the resolution of this gauge is +/- 3psi) the TRP doesn't work well. It may stall a bit and then change the tool, but it usually doesn't. And when it doesn't work well the TRP just before reads about 67 psi (res of this gauge better at about +/- 1 psi).

The funny thing is the reading on the gauge next to the TRP while the tool is changing is pretty much black or white. That is it's either 80psi or 67psi.

I'm guessing it's air regulator going into the VF3.??

Any suggestions on how to further trouble shoot this?

Tony

[Xeno]

TC2, I'm not savy to posting so I didn't know I had to toggle to page 2 till a second ago.
I have a Cat 40 taper.
You may also have a point on the 1/4 NPT. The NPT of the Air Regulator on the VF3 is one size up, most likely a 3/8 but there is a reducing adapter to accept a 1/4 NPT hose coming from the dryer. I plan to take out all 1/4 NPT ASAP!

HaasTec,
Yes, gauge on compressor has low resolustion but seem to be of the 95-120psi family.
I have not verified the pressure there. I'll get another gauge and do so.
When the tool changes, the needle on the gauge at the compressor tank does't move at all.

Currently I suspect one of my regulators doesn't like to have such a low air pressure differential. It may supply some air but the amount/volume it's letting through is compromised.

[Machineit]

One must remember that when hoses etc. are sized for use, it is not the size of the individual fittings that are the consideration, it is the size of the line overall. The line is made larger in diameter to reduce friction in the line during flow. Weather it is water, air or some other liquid or gas it is the distance it travels through the line and the size of the line that matters.

When the tool change occurs, it is a rush of air that will drop the pressure below what is required if the line size is too small or runs too long. The 85psi at the machine assumes that the air is supplied with enough volume that is can maintain 85+ psi at that regulator.

At the terminal points in the machine, IE the relays etc, the holes the air passes through get very small, but they depend on having sufficient volume to be there.

If you find the hose and regulator are good, you may have to check for gunked up relays and filters etc.

Mike

[tc26]

I double checked our input line size.
We are running 1/2" hose on all of our VF2 cat 40 mills.
No quick disconnects, just hose barbs.
The other problem we discovered we had was that there was an air line to another work station in the supply line before it entered one machine.
If a guy was blasting an air gun during a tool change, we had a problem.
That air line has been relocated.