I have been designing a "clip on'" unit for the Replicator for redirecting
the airflow from the fan's to the extruder for cooling. This by turn the
fan's 180 degrees, so blowing in the other direction. By clip on design
there is no need to disassemble the fans, just clamp it between the space
between fan and thermoblock. The clip-ons are changable units for each
extruder for an airflow upwards (to not interfere with the print) and one
blowing under the extruder carriage to cool the print. The units are on the
frontside so it won't affect the X-endstop and the need to adjust the
center of the firmware. Pictures attached.
Now I'm looking closer to the design of the toolheads, I don't understand
some of the design parameters of the toohead. Maybe somebody has knowledge
about this or sees the logic more.
- the heating elements of the extruder are connected to
the aluminium thermoblock. I assume this to have more mass to it so the
heating elements are more stable in temperature?
- Where are the fans for?:
- Do the stepper motors need cooling? If so, then the system of
cooling with two connections through the thermoblock without Thermical
pasta is not that great. The fans are not blowing directly to the stepper
motors. If needed for the steppers, it was better to place them on the
backside, leaving better sight to the filament path.
- Does the thermoblock / heating-units need cooling? And why? they
are switched off/on at the desired temperature.
- Is it for print cooling? Then the airflow is not quite optimal
through the openings left between carriage and thermoblock. Also often not
wanted given unpredictable airflow and therefore tension/splitting in the
larger prints. There are a couple of designs to prevent this airflow on
Thingiverse.
- ore a combination of above?
- Now I understand why it is always difficult to mount the fans. The
fans have holes h.o.h 32mm and the stepper extruder/ thermoblock 31mm.
Therefore are the spacers to wide -to bridge this size difference- and
always disappearing in the holes in the bottom of the replicator. Of coarse
fully understandable holes, because they are for...? DDstarkey has made
quite a few items to pimp the replicator in technical sense.
- I thought the plastic plate on the extruders also was intended to
fasten the extruders that wouldn't make sense. Of course it has to be
replaced by Beefed up Replicator Extruder bracked by MangoT21 and DDstarkey
to get a lasting connection with the fillament tubes, but it is resting on
both the extruders / delrin-unit or cooler, giving friction/tension in that
plate as well the need to loosen it when dismounting the fans. Wouldn't it
better to mount the extruder bracket solitair with spacers to the thermo
block or carriage?
- about the system with the delrim plunger is said enough and of course
everybody has to change this to the Minimalistic MK7/MK8 replacement of
Whosawhatis / Emett
Depending where the fans are for, the mounting could be better imo, not
only because of the difference in measurements between fans and stepper
motor, but also to only give the possibility to disassemble only the unit
you want (so: or fan, or steppermotor, or filament drive-unit) and not the
whole unit. Each time I'm afraid the connector for the wiring is breaking.
Anybody knows about the absolute requirements / reasons? This also because
of the reversing of the fans for the design of the clip-on units I make, by
this the fan is not blowing directly but only ' sucking' air through the
coolers which leaves less cooling I think.
Bart
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