MakerGear Forum

Hello, right now I am working on producing python code that would enable me to coordinate the motion of the MakerGear printer with an Ultimus V dispensing pump (https://www.nordson.com/en/divisions/ef ... -dispenser). It is my understanding that the printer can communicate directly with the dispensing pump and that I can use my pumps communication code to talk to the printer. However, I am kind of at a loss of how to accomplish this task. To complicate things, I also want the pressure/feed rate to be able to be changed based on the response of an external sensor (flow meter) in real time. I'm not sure if this is the right place to post about this, but I have also reached out to the company the makes the dispensing pump about this predicament. I was hoping someone had some experience with a similar idea.

anna661591 wrote: ↑

Thu Oct 17, 2019 3:53 pm

the printer can communicate directly with the dispensing pump

That seems unlikely, as the pump has an old-school RS-232 port, printers have USB ports, and neither has the ability to produce the ASCII-oid protocol required by the other. Back in the day, folks replaced the extruder with a screw-pressurized pastry pooter, but that's not what you have in mind.

Methinks you need a Real Computer™ between the two, particularly with an outboard flowmeter in the mix.

In this context, I'd drop in a Raspberry Pi with an RS-232 converter for the pump, another for the meter (if that's what it needs), a stock USB cable for the printer, and an SSH connection from your Comfy Desk Chair.

If you also expect to feed a 3D model's sliced G-Code to the printer with synchronized pump controls, you should probably start with Printrun / Pronterface (http://www.pronterface.com/) for complete control over the source code; AFAICT, writing a reliable G-Code feeder has more pitfalls than any mere mortal should have to deal with.