Hydraulic Tube Bender - Manual to CNC Conversion

Hi John,

exactly. For thin wall tubes a mandrel is needed.
As i wrote also in my first post, the actual manual machine has its only axis measured by a pot. Its mounted under the machines bending head and 10:1 geared.
When you choose a bending angle on the control panel, its also done by such a pot. (those 8 black knobs you can see on the first link). When both values are equal, the machine knows that the bending angle is reached.
For now i have no clue how to do this in the future with linuxcnc and the ttl encoder.
I have to preset the desired angle and the axis has to move later on (with the bending start signal). The output for the motion valve also cant be high when the machine has reached its fully back position although the encoder maybe flickers (because of some eventually wobble caused by the chain which drives the bending arm)
I hope you understand my problem and maybe you can get me a hint!

Thanks
Conny

Hi John,

the problem its only about the C axis. when i have the machine upgraded to cnc the tube transport unit will make the Z and A axis. (but here i will go with a stepper system with encoders, so there is everything clear to me)

So what i tried to say in my last post. the output for my c axis has to be low until the "bending start signal" comes true.
Also there are other things which have to block the movement (like tool has to be clamped and mandrel position and so on) <=but this works already in my ladder program.

I looked alredy in the docs for the motion or axis pins, but didnt find a solution for interrupting the movement with a presetted position. i am not sure if the spindle is at speed signal is a good way to solve this.

Hi John,

yes and no. I want to have 3 different modes.
-A manual mode for eg. setting up the tooling, where every (hydraulic) movement is made because of a button press on the panel.
-A automatic mode (basicly for single bends) which starts the bending sequence by touching the footswitch.
-And the "new" one: Bending sequences after a bending table with the use of the added Z and A axis

My manual and auto mode are already working so far in CL. (because i simple reused the existing code). Now i have to adapt at least the C axis output to work by gcode. (also to use later the bending table in the "cnc" mode)

Imho the bending sequence or at least C axis movement has to be done with CL because of dependencies with other tool components.
Please look at this . The bending axis only can move if the tool is clamped, the pressure die is attached and the mandrel is in position. Also the pressure die has to move by hydraulic towards the bend (to push the material for better bending quality). On top of that the mandrel has to be pulled back in generally early. Mostly at 5deg before the desired bending angle is reached.

So for i have no clue how the signal for my bending axis valves can be attached to do the movement correct.
I hope its now a bit better comprehensible for you what i was trying to say.

Thank you
Conny

Hi John,

I'm not sure how you could use a bending table in G code.

andypugh did this in the other thread i linked in the first post.
BUT: i didnt get it with the Python code in "bender.py" ...maybe andy can help here.

In automatic mode how do you set the bend angle?

The auto mode gets this value presetted by the pot on the control table. Therefore i was asking the question in post #140281 how to do this in the future by linuxcnc.

For the config files: do you see chances to get it with german named I/O´s?

Thanks
Conny