I used a Low Temp glue gun so that the glue would solidify quicker. You can certainly use a high temperature unit as well. I do not know the specific temperature it was at however it probably was no more than 250F (121C).
here is a link to the Teacup firmware information: https://reprap.org/wiki/Teacup_FirmwareYou could also just use any current open source 3d printer firmware/controller board. The important thing to note is to adjust the parameters for the extruder and a hot glue stick size (calibrate/adjust to the hot glue gun material flow) and to turn off the hot end / extruder heater stuff since the hot glue gun regulates itself.
You can try driving the glue stick directly from the stepper output. You will have very limited extruder resolution as in 1 step is a really big length of the glue stick. Gearing it down (see the big white plastic gear in my extruder picture) allows more steps per revolution. I don't 100% though so I would suggest just try it. Be sure to calculate the correct steps per mm for your firmware though.
Hi, Sorry it took me such a long time to answer your comment. I got most of my stuff from junk inkjet printers. The bearings and gears. The bolts I got from a local hardware store. I tried to source everything as inexpensively as possible. I built this at a time when 3d printing was not well established and it was still a little expensive. No sub $500 3d printers.
Hi, If you already have a 3d printer you are mostly there. You just need to modify your extruder to fit a glue stick. You will need to adjust the filament diameter and the nozzle diameter to the new values. It has been a while since I have done anything with this so I do not have exact values for you. I suggest using the smaller diameter host glue sticks. My nozzle was around 1mm in diameter on the hot glue gun. The only other value you will need is the steps per mm for the extruder. This will depend on your gearing system. Hot glue takes a lot of force and is extruded relatively slowly since the diameter of the glue stick is large so you will probably not be able to use direct drive. You need a big gear ratio to multiply the force of the motor greatly.
Hi. I am really sorry I haven't gotten to your question in 6 year! I hope your project got off the ground and you were able to get something going. From what I can remember I modified the Teacup source to drive my stepper motor boards. The extruder driver was a simple full/1/2 stepping board that had a ULN2003? on it and I drove it from 4 output pins directly. The 3 axis were driven by a 3 axis CNC stepper driver board I bought as a kit and was intended to be driven by a parallel port with step/direction pins. I do not have any of the source code any more otherwise I would post it however there is a ton more stuff now out there to get this done.
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