This is my version of the "LYMAN FILAMENT EXTRUDER".
This version has a:
- Larger Hot end with 350 Watt heater
- Automatic timing system
- fan ducting
- Modified sprokets and hopper
- Adjustable motor speed on the control panel.
Basics of how it works:
Flip on the main switch. This turns on the cooling fan. Then press the red Momentary pushbutton. This activates a 1 second timer that gets latched on and begins the motor timer set for 20 minutes. The latched 1 second timer powers the relay that powers the PID. I used the 1 second timer because I wanted the control mechanics as I made them. Unnecessarily complex, but it's what I wanted.
If you take a look at the parts I used, you might see a lot of dollar signs. The parts that I used were mostly free. I endup collecting a lot of stuff that gets deemed "broken" or otherwise would have been thrown away.
These files are posted to give some ideas to those who are making an extruder. This is by no means a "how to" or anything of the sort.
The STL and sketchup files are included. I hope some will find the data useful.
I'll add on to why I made the changes that I made after some sleep...
I've added a photo of the Rev B hot end. I haven't had time to do anything 3d printer related in the past few weeks, so as far as I have gotten.
I figure I would add this here incase it gets lost...
I started changing somethings around with the extruder. I installed the refined hot end. I changed the hardware to studs for easier mounting. I was going to make a new insulator until I realized that I didn't need it. Air is the best insulator, so with the steel tubing between the hot end and the hopper side, it makes a nice air separation. I've added two photos of it. An issue that I have been having is with the filament getting twisted and jammed in the cooling duct. I did some testing and devised a solution. There needs to be two guides at the outlet. This keeps the filament from arcing too high in the duct. I'll be posting the STL for that soon.
For a BOM, I would look at the original Lyman extruder. I used the same thrust washer, bushing, tubing (DON"T USE LOWES/HOME DEPOT BLACK PIPE), drill bit, etc. For the heater, I used P/N G1442594 available from zorotools.com . The PID was the cheapest USA shipped one I could find on eBay (Item # 150853795607) [I Didn't want to wait 3 weeks from China]. The thermocouple can be found on eBay (Item # 400352110948). The voltage regulator is on eBay (Item #160739335951). I used a different one without a voltage display. I see no need to know what the voltage is.
The drill bit for the nozzle is a #52. The POT on the dash/control panel which controls the motor speed is soldered (via harness) to where is original POT is on the board. I also piggy back the original POT to the dash one to adjust the MIN/MAX of the dash POT. If I only had the one on the dash, the "usable range" would only be a 1/16th of a turn. Using the second POT, I was able to adjust the range to allow a large turn radius of the dash POT to make "usable" adjustments. The POT on the dash is a 10K POT from Radio Shack. It had a secondary on/off switch piggyback underneath. That mech made the POT have a detent. I didn't want that, so I took the POT apart and disabled that.