Wohlhaupter UPA-4 push button issues

I have one UPA-4 that has been in storage for a while and now I have issues with the 12 push buttons that will not release.
These buttons have been pushed in and been so for some years (I have never used this head yet!)

Have been following manual but I get no response at all, does anybody here have a UPA-4 that might have tips and tricks for the boring head?

Grateful for any assistance I can get.

Cheers
Bengt

Have you tried giving it a good cleaning and soaking it in penetrating oil?

Ongoing soaking, was a bit *stiff* but all parts moving except the release ring for the buttons.

Searching pictures on the web shows that there are some parts that are not correctly positioned.







Here a part of what I understand is the release ring is not correctly positioned?
The ring can be moved to left with a screwdriver, it is spring loaded.

Any ideas?

Managed to get all parts off and I must say that this really German quality stuff.

Now I have some cleaning and re greasing/oiling to do and hopefully I will get it working OK again.

I have a slightly different UPA4. It is the most beautifully-made thing I have ever handled.

Mine has pairs of pins with their axis along the spindle axis. The pairs are coupled with tiny gears, so that when you push one down the other pops up.

I also have a UPA3 which I use extensively.

I even have a _CNC_ UPA3:

Wow,that is interesting. Something you have made your self?

I also have a modern 236 set with ISO40 taper = I like it very much.

The CNC adaptor was an experiment. (It should fit any changeable-shank UPA3) but wasn't 100% successful.
I should try it again using the STMBL drive instead of the 7i33.
The main problem with it was the internal home-made encoders. But also the design of the hand-wound 100% custom motor could probably be improved.

I am intrigued of such engineering. Have no need for such tooling now but who knows what i might need in the future.

So, keep up the good work!

Here are the pins, they are badly worn in the end that connects to the star wheel.
Have contacted Wohlhaupter in Germany to hear if they have spare parts to reasonable price.

3-4 out of 12 are OK.

Now all parts cleaned and greased/oiled awaiting final assembly with new pins.

As I see it the main reason to the faulty behavior is lack of grease and oil.