Toolchanger / Drawbar Strangeness all the sudden

First off, thanks ahead of time for any help or assistance you may have.

This weekend my super mini mill started acting funny on tool changes. I have 2 items I have noticed.

1. When I remove a tool from the spindle manually, it works fine, but when I release the button to grab the tool it makes a squealing noise briefly, kind of like when you pull the opening of a balloon when you let the air out sound.

2. When a Tool Change is commanded it works fine, but sporadically it acts strangely. It goes as planned until the spindle goes down and grabs to the tool. You get the above sound, then after drawbar closes, it just sits there for a second or two. It never did that until this weekend. It does not do this on every tool.

Any help would be greatly appreciated, and if anyone is willing to discuss over that phone I would open to that help as well.

paris_tj said:

First off, thanks ahead of time for any help or assistance you may have.

This weekend my super mini mill started acting funny on tool changes. I have 2 items I have noticed.

1. When I remove a tool from the spindle manually, it works fine, but when I release the button to grab the tool it makes a squealing noise briefly, kind of like when you pull the opening of a balloon when you let the air out sound.

2. When a Tool Change is commanded it works fine, but sporadically it acts strangely. It goes as planned until the spindle goes down and grabs to the tool. You get the above sound, then after drawbar closes, it just sits there for a second or two. It never did that until this weekend. It does not do this on every tool.

Any help would be greatly appreciated, and if anyone is willing to discuss over that phone I would open to that help as well.

Click to expand...

Marginal air pressure, I would guess. Supply line kinked? Clogged? Are you using an air dryer?

Thanks, Larry D. for the reply.

I have 145-175 psi at my source, an 80 gallon Quincy compressor. I see no kinked lines. No dryer, just 2 FR's that are inline between the source and the machine, which has another FR on it which is set to 85 psi.

The air blow-off line attached to the machine seems fine, no lack of pressure or volume there.

I have had the machine for about 6 months with this setup, and no issues like this at all until this weekend. I am running a very tall setup which is splashing coolant up on the change and bottom of the head more than normal.

Could the FR on the machine cause this, it is old and rusted? I took the water trap off to take a look this weekend and saw nothing but rusted spring in it, no visible water. Spring was rusted I noticed when I got the machine. So when I put it back together it blew the water trap off. I have reattached and it leaks now more than it did. I have a new FR ordered from Amazon, hopefully it does not have to be Haas specfic. My pocket book is tight so I just got a 3/8 IR one.

If the machine has been run without an air dryer, there's no telling what things may look like inside. Especially if the spring in your filter is rusty, that's a bad sign.

You might try squiring some Marvel mystery oil in the air line and see if that frees things up.

I believe my air is fine, no drier but multiple traps(Not perfect, but better than average). I paint and all with my air and have no moisture issues. That does not mean it was not affected by the previous owner.

I will give that a try, anything else you think I can try/look at tonight when I am in front of the machine. Where would be the best place to inject the oil so the filter does not catch most of it, Outlet side of FR?

This is my first machine, first Haas, and I am not that familiar with it.

Sound like this?
27 Haas mini mill tool release piston noises #1 video - YouTube

I would hesitate to put oil into the system. Causes more problems than fixes.

If you have the manual look up the drawbar assembly so you have an idea of it. Take a mirror and bright flash light and look up into the spindle. I am betting it may be a mess - use a penetrating oil and nozzle to spray up in there and cycle tool release, repeat as needed until clear. Wipe taper bore well.

Put a dab of grease, I use Lucas Red "N" Tacky, on a clean tool pull stud and install, cycle a few times not really letting to tool out. Remove tool and wipe excess grease from taper - this is a monthly routine for me.

If that doesn't help then you need to dig into the air system at the tool release piston assembly. There is a fair description in the manual. None of it is hard - just don't fool with the switches and you'll be fine. I suspect trash in the lines, clean with denatured alcohol.

Most likely the noise you describing is coming out of the quick exhaust valve that usually located on top of the tool release piston:
Take it apart and look at the rubber membrane inside it might be all dried up and started to crack on the edges causing the tool release piston to retract slowly. (that explains why the machine stops during the toolchange, it just waiting for the signal that tool release piston is fully retracted)
Also you can get the manual from diy.haascnc.com if you dont have one yet.

It does have a certain reed instrument tone to it - clever!