heated build platform and stepper extruder
rbisping
almost 25mm of my build height. oh well :) Im also running it off of a
second motherboard and extruder since i have been having some
difficulty finding the firmware update to run it off my mb extruder.
Something else i was thinking about, It might be better to have the
platform heater connected to and controlled by the mb rather than the
extruder controller, though the mb doesnt have the high power outputs
built into it so maybe its not as good of a idea as i thought at
first. But my reasoning is, in a makerbot it wouldnt make that much
difference but in a mendel the movement difference between the
extruder and the build platform might cause some issues so having the
build heater connected to the motherboard would be a advantage and not
detrimental to a makerbot either.
second thing was about incorporating the mendel stepper extruder code
into the standard makerbot firmware and multiextruder control and
differentiation ability. I haven't looked at mendels mb firmware and
compared it to makerbots sufficiently to be able to tell how easy it
will be to merge them together. having two different firmwares without
a real good reason doesn't seem advantageous to me but if there
really is a good reason i would like to understand it :)
Ethan Dicks
> well, i got my heated build platform assembled today though it takes
> almost 25mm of my build height. oh well
Unfortunate, but the stuff I want to make, at least at first, isn't tall stuff.
> :) Im also running it off of a
> second motherboard and extruder since i have been having some
> difficulty finding the firmware update to run it off my mb extruder.
I haven't gotten that far, but my understanding is that right now, you
have to locate the tip revisions in the source repository and build
from scratch. I've gotten _a_ version of the 1.6 extruder firmware
and gotten it to build, but I haven't yet put together a heated build
platform plus the 1mm thermistor table (my ultimate goal).
> Something else i was thinking about, It might be better to have the
> platform heater connected to and controlled by the mb rather than the
> extruder controller, though the mb doesnt have the high power outputs
> built into it so maybe its not as good of a idea as i thought at
> first.
It's not just the lack of high-power output - that can be fixed with
an external MOSFET (cost, under $2). The Motherboard has one free I/O
pin. Everything else is assigned and routed somewhere. You'd have to
steal a pin from something else on the board, diverging the hardware
from the standard build. In the case of the extruder controller,
there are free analog pins (with connectors and easy to get to) _and_
a free high-power output channel with screw terminals - simple to
interface to.
I agree that the motherboard is probably the better place to control
the bed from, but it's out of resources. I'd say that it's a good
suggestion for the design of the AT-MEGA-based motherboard that's
still on the drawing board (a pre-wired thermistor channel and a
pre-wired high-output channel).
-ethan