Solenoid vanne to inject material


i want know if any plug in can help me to start e relay when the printer extruding to exchange my stepper motor extruding systeme for a solenoid vanne to inject pressure material

this will be useful to inject many kind of material like chocolate or sugar better than actual systeme

i not foud solution on any led controle plug in, actualy i not found an option to start relay when extruding...

i know do somethink really singulary ,thank you to read me ,and for future answer


The process sounds like a foam-injection station (which I used to operate in a plastic manufacturing plant). In this case, there are two cylinders of material.

You haven't indicated the pressure you need for your valve; this is important. You should be able to find these valves for different industries depending upon the material (hydroponics, beverage-dispensing systems).

I'm not sure how you would package the chocolate, for example, so that it may be extruded. Nobody sells chocolate filament.

3D printed chocolate

I imagine that it would be difficult to keep a batch of chocolate very long after it has been made ready to print.

The problem with an OctoPrint-based solution would be that this is a firmware-based problem. OctoPrint sends commands over to the printer controller and it extrudes when it wants to extrude. OctoPrint doesn't know when the printer is running which line of gcode. So if you try to use an OctoPrint plugin to control a valve the timing will be off.

Assuming for a moment that you have a custom firmware what you could do is to adjust the gcode to add another tool.

Typical gcode:

G1 X0 Y100 E20

This could be adjusted to:

G1 X0 Y100 E20 A10

In theory, the firmware could interpret "A10" to mean that it should inject (extrude) a certain amount of the nitrogen or whatever gas that you're trying to use. The timing now is correct; the printer will do both things at once.


thank you for the answer

apparently i will need a custom firmware and ad a second tool on firmware look like the great
solution . sorry to disturb you with a firmware probleme its apparently more a marlin forum topic

for extrude chocolate beter than actual common stepper systeme on thingivers

i want use paint pressure chamber who will stay in hot water when print and controle extrude per solenoid vanne and 3d printed pressure regulator .

thank you for your attention and for your time


Feel free to discuss it here if you would like.

The Thingiverse chocolate printer you linked was unique. I do like that method of extrusion for soft materials like this. And I think you may have the right idea of adjusting the top pressure of the cylinder with gas rather than a stepper motor.

Chocolate works well with a double-boiler method in which water is heated which then warms the chocolate itself. You have the right idea again with this.

You might also review the Smoothieware board and firmware which is likely easier to configure than Marlin. It readily supports 6 axes (tools/motors/dimensions, if you will).

I would guess that you're looking for an outer chamber which includes a trapped reservoir of water and is wrapped in a hotend heater. You would also need a thermistor to measure the temperature. And then it should have a dry inner chamber which accepts the removable chocolate cylinder which itself has a pressure valve to accept a gas. The gas could simply be compressed air of course.

And don't forget that you may need a method of reversing the pressure (retraction) which is possibly a harder problem to solve. You may need a second valve to either relieve pressure or to actually reverse the pressure by vacuum.


thank you for the invitation to continue the topic and your kind answer and observation

for the hot end i will not need the pipe who go to the head is big cose i lost to much power per friction iside a small pipe that made big volumetric material , all will stay hot by massive. i will just need a fan like this to cooling what i printing.

i thinking about a solution out of firmware and programmation difficulte .
maybe you can help me i want know if i remove a stepper polulu from a ramp1.4 can i use the direction signal to activate my relay with out risk for the cart.
i know use stepper with out engine connected is dangerous for stepper. do you know if use cart with out stepper is dangerous for the cart.

thank you again for you time ,and thank you to the people of octoprint community to atach time to my problemes


I don't understand the language (German I think) so I can't tell what he's describing in the video, but, it doesn't look like a solenoid. It looks like a stepper motor to a gear to a wormgear which doubles as a piston (see breakdown pic with nut and threads on rod)

As for solenoids, I thought they were all the way in, or all the way out. I didn't know you could micro-adjust them


i do not want do like the video i want activate solenoid valve
in place of extruder


Okay, I understand. Adjustable flow solenoid valve with a constant pressure on the line which goes to a pump and then a piston

Makes sense.

On first thought, it would seem that usage of retraction could close the valve, and extrude could open it. But, I haven't thought it completely through


It depends upon the distance (volume) of chocolate that has past the valve which is under pressure. Merely closing the valve still leaves that portion of chocolate pressurized and it would tend to ooze.

I'm afraid I don't know much about those Polulu daughter boards. I don't understand "i know use stepper with out engine connected is dangerous for stepper". If you're worried about running a Polulu without a stepper then it might be possible to add a load (resistors) and adjust the current control so that it's almost nothing.