Question ATC problem

Hello,
I have an automatic tool changer (Item number: 10012) mounted on a spindle AMB 800 FME.
It is connected to a compressor (6 to 8 bars) and controlled by a 5/2 distributor (the air is ejected when the air is shut off)
I used it a few times.
Sometimes the ER11 clamp is stuck when I send air.
The only way to remove the tool holder is to force it by hand or with a screwdriver.
I added an air filter and an ISO VG32 oil for the lubrication at the outlet of the compressor, but the same result.
I do not use stepcraft support for the ER11 collie, but I made a support in wood with holes of 20 mm. The ER11 collar is dropped in a hole at 10 mm from the support.
When it is stuck, I tried without support under it, same result.
For now, I have never machined parts with spindle, so there is no dust in it.
Do you have an explanation why he stays stuck?
Does it need to be greased?
Thank you.

Hi,
I got only the HF500-ATC and had the same problem.
It became better after cleaning both the collet's cone and the tool holder on teh ATC side.
I used an industrial detergent for cleaning brakes (in german it is called "Bremsenreinger").
It removes dirt and oily coating.

Hi,
Thanks for reference for cleaning ATC.
When we looking at the ER11 support of stepcraft, the entry of the ER11 clamp is done on the side.
But when we draw back the spindle, it is possible that ER11 is maintained by the support and that the spindle goes up, so it may need a force which hold the ER11.
And when ER11 is very clean it step-down whit out any force
Can anyone confirm this?
Thank you.

Hey guys, i've the same problem with HF-500 and ATC, anyone who found already a solution?
I've already cleaned with "Bremsenreiniger", no result.
But the SK10 doesn't stuck after short milling or engraving. Only if i mill in "harder" wood...

Hello,
The solution is: you need more pressure, it can work at low pressure (5 bar), but for best result in any case you need 10 bars.
But, be careful that your pneumatic distributor can support 10bars.
The mostly a pneumatic distributor, and compressor have maxi at 8 bars.
Your compressor must regulate between 9 and 10 bar.

Thanks