Minimill Toolchanger Problem

[Pondo]

I have a 2006 Minimill with a 10 tool umbrella changer. I got an alarm 127 - No Turret Mark about 2 weeks ago. I powered it down and restarted it, then it worked fine. Last week it came up again with the same result. On Thurs it did it again, but now it will not work at all. Alarm 115 - Turret Rotate Fault comes up when it tries to reset the indexer. It will not let me home any axis, and therefore I can not run any parts.
All I need for now is one tool to do some engraving, so even being able to bypass the changer would be fine until I can get it looked at properly.
I can't even get the covers off the changer to get a look at any sensor that may be boogered up.
Any help or suggestions would be welcome and appreciated.

[haastec]

If the turret rotates but eventually alarms out with the 127 alarm, check the limit switch for the carousel; it could just be sticky. You can watch the switch in the diagnostics page to see if it is working properly when manually actuate it.

Hope this helps.

[Pondo]

Originally Posted by haastec If the turret rotates but eventually alarms out with the 127 alarm, check the limit switch for the carousel; it could just be sticky. You can watch the switch in the diagnostics page to see if it is working properly when manually actuate it. Hope this helps.

I'll give it a shot.
Do you have any tips for getting the shroud off of the toolchanger?

[dougtyler]

It is most likely a proximity switch that has a chip on it. I got this same problem a few times, then started turning down the coolant pressure to keep from blowing the chips up into the changer. Does your machine have the high pressure pump option?

To fix the problem, make an empty tool change, e-stop the machine when the umbrella comes to the spindle. Now you can reach in an wipe down the inside of the changer. Then recover.

[Pondo]

Originally Posted by dougtyler It is most likely a proximity switch that has a chip on it. I got this same problem a few times, then started turning down the coolant pressure to keep from blowing the chips up into the changer. Does your machine have the high pressure pump option? To fix the problem, make an empty tool change, e-stop the machine when the umbrella comes to the spindle. Now you can reach in an wipe down the inside of the changer. Then recover.

That's what I'm thinking it is too.
Problem is that the machine will not home. It tries to index the toolchanger and it alarms out before it will allow it to home. I have been trying to remove the housing around the changer to get in there and clean the sensor off, but can't.

Is there a way to have the toolchanger come out without homing the machine?

Or can the toolchanger be disabled, then the machine homed?

Any other ideas?

[dougtyler]

Are there any empty pockets? It might sound like a bad idea, but if there's an empty one you might be able to get the air gun in there, to get the chip blown off, to be able to home the machine. Then you could do a thorough cleaning afterward.

[Pondo]

Originally Posted by dougtyler Are there any empty pockets? It might sound like a bad idea, but if there's an empty one you might be able to get the air gun in there, to get the chip blown off, to be able to home the machine. Then you could do a thorough cleaning afterward.

Good idea.

Tried it, but no luck. Where is the sensor?

[fuzzyracing1967]

Just a thought don't know if it would work but maybe. You say it alarms out while trying to home the changer (most likly tool 1), I think there is a setting to call out what # tool to call home, so why not change it to the tool # that is in the spindle? Maybe

[haastec]

Actually, you should just be able to use "zero ret" mode then press "auto all axis" ("all axis" depending on year of machine). This will home the machine without changing the tool to #1.

[Pondo]

Originally Posted by haastec Actually, you should just be able to use "zero ret" mode then press "auto all axis" ("all axis" depending on year of machine). This will home the machine without changing the tool to #1.

It won't let me get to that point.
It indexes the toolchanger about 3 pockets and then alarms out before allowing any other axis to home.
I got into the habit of using "Auto All Axis" (just "ALL" on my machine) instead of the power up because of a large indexer on the RH end of the table. If you toolchanged at X home it would hit the indexer.

Does this sound like a blocked or bad sensor?
Where is the sensor?
I can follow the wires to the 2 prox sensors for the shuttle in and out locations, but I still can't get into the umbrella to see anything in there.
Do I have to remove the entire bottom plate with the tools in it?
Do I have to remove the entire toolchanger?
Is there a way to bypass the toolchanger completely?

[Geof]

It does sound like a proximity detector problem. The proximity detectors for the rotation are near the center hub toward the front side.

Here is a possible way to get in and wash off any chips. Connect a hose (garden hose) with a spray nozzle to the coolant pump (I hope you have the high volume pump). Haas used to supply washdown hoses and nozzles so you may have got one with the machine.

Now get a small screwdrive and slide back a pocket cover on the carousel disc; these arejust held closed by springs. Spray water into the carousel enclosure throught the open pocket, lots of water in all directions through different pockets.

If you still cannot get it to zero repeat the water spraying a few times; sometimes chips get glued on by coolant residue and will not wash off easily.

You may have success with this method, I have a couple of times, but if it doesn't work you go to the next step.

Look at the bottom center of the carousel plate and you will see a ring of 5/16" socket head cap screws. These hold the plate onto the hub and you can remove them to take the plate off. Be careful it is awkward and heavy and if there are tools in any pockets dangerous (I have the scars to rpove that).

Once you have the plate off you will be able to see the detectors inside the top near the hub.

[Pondo]

Originally Posted by Geof It does sound like a proximity detector problem. The proximity detectors for the rotation are near the center hub toward the front side. Here is a possible way to get in and wash off any chips. Connect a hose (garden hose) with a spray nozzle to the coolant pump (I hope you have the high volume pump). Haas used to supply washdown hoses and nozzles so you may have got one with the machine. Now get a small screwdrive and slide back a pocket cover on the carousel disc; these arejust held closed by springs. Spray water into the carousel enclosure throught the open pocket, lots of water in all directions through different pockets. If you still cannot get it to zero repeat the water spraying a few times; sometimes chips get glued on by coolant residue and will not wash off easily. You may have success with this method, I have a couple of times, but if it doesn't work you go to the next step. Look at the bottom center of the carousel plate and you will see a ring of 5/16" socket head cap screws. These hold the plate onto the hub and you can remove them to take the plate off. Be careful it is awkward and heavy and if there are tools in any pockets dangerous (I have the scars to rpove that). Once you have the plate off you will be able to see the detectors inside the top near the hub.

I'll give that a try. I installed a washdown hose the first day I got it.
I have 7 of 10 pockets with tools in them, so I have been hesitant to drop the plate.
What I am going to try if the washdown doesn't work is to remove the pin that forces the cover open and closed. Then I may be able to open it and get in to the sensor. At least I'd be able to remove the tools before dropping the plate, right?
If I can't get it done tonight I'll have to call Haas.
I'll post up the results.