Problem- Problems on tool change

[CORBIN92087]

We have a HAAS vf-2 CNC and are having troubles on the tools changer. When the tool carousel grabs the tool out of the spindle and pulls it out, it makes a loud popping noise. Its like whatever holds on to the pull stud of the tool is not releasing and forcing it out. Its also very inconsistent, it seems to pop more after doing heavy machining for a longer period of time. any ideas why this is happening and what we can do to prevent it? it cant be good for it...lol

[wcbob]

try and lube the top of spindle taper very lightly and draw bar

[Geof]

This fairly common especially after a bunch of heavy machining; the tool seems to settle tighter in the taper.

The carousel does not pull the tool out of the taper there is an air cylinder at the top of the spindle that is supposed to release the drawbar and knock the tool out as the spindle lifts up during a toolchange. Sometimes when the tool is tight the knock out is not enough and the little bit of extra force from the carousle lfting is enough to release it but really it should release just from the knock out.

You can reduce the sticking by making sure you keep the spindle taper and tool holders nice and clean; don't let a film of dried out coolant form keep them well wiped with just a thin film of light machine oil.

If you keep track of what holders stick the most you can maybe use these ones for only light cutting; we have found there is quite a variation between holders even from the same manufacturer.

Another way to get a better release is to install a reserve air tank on the low pressure side of the regulator on the machine. The machine pressure should be 85 psi but when the tool changer operates it often drops to around 65 psi because air cannot flow through the regulator fast enough and the knock out cylinder moves slowly. A reservoir tank on the 85 psi side keeps the pressure up.

[JoBwan]

Originally Posted by CORBIN92087 We have a HAAS vf-2 CNC and are having troubles on the tools changer. When the tool carousel grabs the tool out of the spindle and pulls it out, it makes a loud popping noise. Its like whatever holds on to the pull stud of the tool is not releasing and forcing it out. Its also very inconsistent, it seems to pop more after doing heavy machining for a longer period of time. any ideas why this is happening and what we can do to prevent it? it cant be good for it...lol

I totally agree with Geof's reply. I have found that using "Tri-Flow" lubricant and scotch-bright pads on the toolholders will help keep them from gumming up. I aslo use the "Tri-Flow" and a rag to keep the spindle taper cleaned and it seems to make a huge difference!! Check your Ace hardware or Auto Zone for the "Tri-Flow" aerosol. Good Luck!!!

[dougtyler]

Another thing to try is car wax. Use one that has teflon in it. I use turtle wax spray.

[stevo1]

Geof's resopnse is the most common thing to have the tool stick in the spindle. Our tools would stick from time to time but it was not because of heavy machining it was from long runs of high feed machining. The tool would heat up enough to make it stick becuase we were using airblast instead of coolant.

Stevo

[HuFlungDung]

I was reading a report about how the taper shank tools swell at the small end from having the pullstud installed. Apparently it is a significant amount, due to the leverage of the slope of the threads, I suppose. Although this report was created by someone who was selling an 'anti-swell' type of pullstud, it might be worth checking out.

It would be fairly important not to overtighten the pullstud for this reason. It might even make sense to use blue loctite on the threads to ensure good stud retention under conditions of less torque.

[panaceabea]

I think you need to check the solenoid that preloads the trp with air before releasing the tool. Its right behind the front cover and has a small hole on the end with the coil that you can stick a small allen wrench in to depress the piston. If this solenoid is the slight bit slugish in opening the piston that ejects the tool holder wont push it out.

I just went thru this exact issue over the past few weeks, started with a loud pop when extracting the tool , longer the tool was in the spindle the louder the pop, eventualy it wouldnt release the tool holder at all.

Service tech walked me thru the test procedure of pushing the button on the solenoid and it proved to be the problem. You can squirt a few drops of tool oil in the inlet side of the solenoid , cycle the solenoid a few times by pressing the button and see if it lessens the problem .

Make sure you have your hand under the tool holder when you press the little button , If the solenoid is the problem you will see a huge difference in the way it ejects the tool with the button on top of the solenoid verses the tool release button.

[CAN MACHINE]

I have had a problem with my tools sticking in our VF1. I have found it happens when a tool has been in the spindle for a long time or heavy machining. I read all the posts in this thread and I tried a little light air tool oil on the tapers and it has solved my problem. Thanks to all.

[HelicopterJohn]

I don't do a lot a heavy machining so this may not be of any value.

I had issues with the popping sound during tool changes. Now on a monthly basis I disconnect the air supply to the machine (with the machine off) and disconnect the air line at the regulator that goes to the drawbar release and put 15 to 20 drops of air tool oil (I get mine at NAPA) in the hose and then reconnect it. During the next few tool changes you will see a little mist as the air tool oil works it way through the drawbar release mechanism.

So far it has worked well for me and no more popping during tool changes.

Just something you might want to consider if you can't get rid of the popping during tool changes.

John

[Vern Smith]

I like the air tool oil idea, I used air tool oil in pneumatic systems years ago with good results, forgot about it. It was a necessity with air ratchets, particularly if there was a lot of moisture in the air lines.

I had trouble with tools sticking in the spindle as well. The local HFO suggested spraying dry lube on the tool tapers. I have not had a bad problem with it since I started to use the dry lube. Some still clunk pretty bad if they have been in the spindle for a while or are hot.

Vern

[03clipse]

this is a coman thing. but i have had it for years and nothing is broken yet. just keep everything clean. scotch bright is great. I also have heard that it is more with Parlec holders than others