MK1-250 - Revision history

Davo at 14:03, 8 December 2025

2025-12-08T14:03:48Z

Davo at 14:00, 8 December 2025

2025-12-08T14:00:46Z

Davo: /* Changing Nozzles */

2025-12-08T13:58:47Z

‎Changing Nozzles

Davo at 15:42, 19 October 2021

2021-10-19T15:42:27Z

Davo: /* Description */

2021-03-15T14:17:12Z

‎Description

Davo: /* Firmware */

2020-06-22T19:56:47Z

‎Firmware

Davo: /* Changing Nozzles */

2020-06-19T17:32:23Z

‎Changing Nozzles

Davo: /* Maintenance */

2020-06-19T17:31:15Z

‎Maintenance

Davo at 16:06, 25 February 2018

2018-02-25T16:06:32Z

Davo at 19:38, 11 May 2017

2017-05-11T19:38:36Z

@@ Line 5: / Line 5: @@
 |}
-<span style="color: red;">'''The MK1-250 has been discontinued, and replaced with the FH2-260.'''</span> It was our primary workhorse print head, and works for standard (rigid) 1.75mm filaments which print at temperatures up to 250°C.
+<span style="color: red;">'''The MK1-250 has been discontinued, and replaced with the FH2-260.'''</span>
 [[File:MK1-250.png|300px|left|MK1-250]]

@@ Line 5: / Line 5: @@
 |}
-The MK1-250 is our primary workhorse print head, and works for standard (rigid) 1.75mm filaments which print at temperatures up to 250°C.
+<span style="color: red;">'''The MK1-250 has been discontinued, and replaced with the FH2-260.'''</span> It was our primary workhorse print head, and works for standard (rigid) 1.75mm filaments which print at temperatures up to 250°C.
 [[File:MK1-250.png|300px|left|MK1-250]]

@@ Line 98: / Line 98: @@
 === Changing Nozzles ===
-How to disassemble the nozzle from the MK1 head:
+How to disassemble the nozzle from the filament head:
 # Carefully:

@@ Line 28: / Line 28: @@
 **Conductive PLA
 **SS PLA (Stainless Steel infused)
 *PVA (PolyVinyl Alcohol)
 *T-Glase

@@ Line 49: / Line 49: @@
 # Beneath this, the filament enters into a 2mm ID PTFE guide tube, which leads the filament to the brass nozzle, with which the PTFE tubing mates.
 # At the nozzle, heat is transferred to the filament, whereupon it is forced out through the brass nozzle. Nozzles are available in 1.0mm, 0.75mm, 0.50mm and 0.35mm sizes, as well as blanks, which you can open up to your own custom diameter.
 == Loading the Head onto the Printer ==

@@ Line 88: / Line 88: @@
 == Firmware ==
-MK1-250 heads from the 2015 onward should have platinum RTD wires, and therefore use the firmware labeled "FILAMENTS_33A.hex" or "hothead.mk400.33A.hex" (these are actually the same file with different names).
+With version 4 and later, all heads take the same firmware!
-MK1-250 heads from 2014 and earlier should have red RTD wires, and therefore use the firmware labeled "OLD_NOJUMPERS_232A.hex" or "hothead_232A.hex" (these are also the same file with different names).
+With version 3 and earlier, MK2-250 heads all use the firmware labeled "FILAMENTS_33A.hex" or "hothead.mk400.33A.hex" (these are actually the same file with different names).
 == Maintenance ==

← Older revision		Revision as of 17:32, 19 June 2020
Line 116:		Line 116:
	# Use normal procedure for heating and loading filament.		# Use normal procedure for heating and loading filament.

−	Please let me know if any of that is not clear. You really should not have to do this. If you replace our nozzle with some other nozzle, you may have issues, because ours is designed to mate with the guide tubing with no gap.	+	Please let me know if any of that is not clear.
		+
		+	'''You really should not have to do this. If you replace our nozzle with some other nozzle, you may have issues, because ours is designed to mate with the guide tubing with no gap.'''

← Older revision		Revision as of 17:31, 19 June 2020
Line 97:		Line 97:

	Very little maintenance is required on this head. Use a wire brush or tweezers to remove any excess plastic on the nozzle, and use a shop vac or air hose to suck or blow away any buildup of eroded filament in the feed chamber and/or on the hobs (teeth) of the motor shaft.		Very little maintenance is required on this head. Use a wire brush or tweezers to remove any excess plastic on the nozzle, and use a shop vac or air hose to suck or blow away any buildup of eroded filament in the feed chamber and/or on the hobs (teeth) of the motor shaft.
		+
		+	=== Changing Nozzles ===
		+
		+	How to disassemble the nozzle from the MK1 head:
		+
		+	# Carefully:
		+	# Heat to the printing temperature of the material loaded.
		+	# Move the manual lever to the left, retracting material until it is free of the hobbed shaft, then remove by hand.
		+	# Turn off heat to the head and remove it from the yoke.
		+	# With a 1/4" driver or wrench, remove the nozzle.
		+	#. Inspect the nozzle cavity for any stray material; if found, remove with tweezers, solvent, air pressure or other means.
		+
		+	How to reassemble the nozzle on an MK1 head:
		+
		+	# Carefully:
		+	# Ensure your MK1 has no filament loaded.
		+	# With a 1/4" driver or wrench, attach the nozzle.
		+	# Use normal procedure for heating and loading filament.
		+
		+	Please let me know if any of that is not clear. You really should not have to do this. If you replace our nozzle with some other nozzle, you may have issues, because ours is designed to mate with the guide tubing with no gap.

@@ Line 75: / Line 75: @@
 # Straighten (if needed) the last few cm of the new filament, which should be routed through the guide tubing. Insert it down through the pneumatic fitting on the top and centered between the two bearings, between the bearings and the drive shaft of the motor.
 # Press the manual feed lever to the right, advancing the filament until the lead end advances into the white PTFE tube.
-# In repetrel, click the motor on at 500 (pulses per minute) until the new filament advances to the melting zone and forces the old filament out. Advance about 30cm of filament, checking for smooth sides and uniform color.
+# In repetrel, click the motor on at 500 (pulses per second) until the new filament advances to the melting zone and forces the old filament out. Advance about 30cm of filament, checking for smooth sides and uniform color.
 # Remove excess filament with tweezers. Seat the guide tubing. You are ready to go.

@@ Line 7: / Line 7: @@
 The MK1-250 is our primary workhorse print head, and works for standard (rigid) 1.75mm filaments which print at temperatures up to 250°C.
-[[File:MK1-250.png|200px|left|MK1-250]]
+[[File:MK1-250.png|300px|left|MK1-250]]
 This includes the following materials: