I'm looking for a team that is interested in dual extrusion on UM2.
To realize dual extrusion on this machine the team should have skills like:
-programing firmware (using actually tinkergnome firmware)
-Plugin for Cura
-people testing the equipment.
-CNC programing/milling ->that's me.
Main issue in dual extrusion is oozing.
To fight that problem I have created a tiny aluminium chiller and a new design for a really fast heater block.
To prevent oozing it is necessary to decrease the temperature of the inactive tool by ~40°, depending on the filament you are using.
In my design the aluminium chiller replaces the small fan , the cooling rib and the bottom hot end holder in the tool head (it makes no noise when idle:))
At the beginning I made test with Olsson block and was disappointed because of long cool down and heat up times.
In the next step I did a redesign of the Olsson block.
1st: Having the extruded material exactly between heater cartridge an PT100 sensor.
2nd: Reduce thermal mass.
3rd: Reduce weight.
Now I'm at a point where I need your help.
The firmware of the printer needs to be improved.
The way I would prefer is:
add a new variable to the file "Material.txt" called "idle_temperature" this variable is stored with each material in the printers software. It should be possible to edit the value online.
When printing a part and there is a tool change ahead, the printer should move to tool change position and heat up the new tool, cool down the inactive tool.
Example:
G1 F900 X103.178 Y39.538 E193.22154
G92 E0
G10 S1 ;retract before tool change is already implemented
G1 Z0.275
T1 M6 ; M6 = move to tool change position -> heat up / cool down extruders
G0 F9000 X75.509 Y72.471
;TYPE:SUPPORT
G1 Z0.200
G11
G1 F1200 X75.509 Y81.131 E0.69280
G1 X66.849 Y81.131 E1.38560
G1 X66.849 Y72.471 E2.07840
If you are interested, I can provide you:
-A set of heater blocks, replacing Olsson or standard heater block (without nozzles).
-CNC milled dual head chiller. with 2 tube connectors 4mm
-A light weight fan holder as stl file or printed in Polymaker PC-Plus /black .
The cost for a set of heater blocks + water cooled chiller will be 120€.
You need of course a second extruder with all parts leading to the tool head.
A external 80mm aluminium chiller 12€
A brushless water pump. 4€.
Greetings Roland