MPSM Side-Port V6 Hot-End Mount for ABS by DtEW

Last crawled date: 3 years ago

This is a special-application^ mount and fan duct set to adapt an E3D V6-style hot-end^^ for use on a Monoprice Select Mini/Malyan M200 printer.
^ See "THE PROBLEM" below.
^^ The design of this mount was based on a RepRap Champion V6 hot-end as the reference, which I understand to be a good functional clone of the E3D V6 hot-end. It is likely that it's also a dimensional clone, esp. for the parts that matter to a mount (i.e. heat-sink). If you have an genuine E3D V6 hot-end and a pair of quality calipers, message me and we can trade notes on dimensions.
THE PROBLEM
The MP Select Mini/Malyan M200 is a compact, unenclosed, single-gantry-style printer whose electronics is integrated into the main body under the build area. In the absence of an enclosure, it is particularly hard for it to print ABS without warping. At the same time, typical enclosures that people make for this printer puts the electronics in the warm air, which then creates potential issues with heat dissipation.
As easy as it is to focus on the lack-of/need-for an enclosure to maintain the sort of build area temperature associated with successful ABS prints, the real problem is that of heat loss by the printed part. Observation suggests that the stock fan/heat-sink for the hot-end contributes significantly to that heat loss. Even with a modified fan shroud that deletes (or nullifies) the print cooling duct on a bone-stock setup, the airflow that goes into the stock heat-sink can only exit above (harmlessly) and below (right into the print area after it goes around the heater core). It does both. The constant flow blowing out of the bottom of the stock heat-sink exacerbates the cooling rate of the topmost layers, which of course then results in lifting and warping.
There is little we can do about the air exit paths of the stock heat-sink (short of blocking-off one end, which would be inadvisable), as it is part of a proprietary hot-end. The only saving grace is that the stock 30mm fan does not generate a great deal of airflow, but is mostly sufficient at staving off the heat-creep of the stock hot-end.
But... what about a different hot-end/heat-sink? Can the heat-sink exhaust (and intake, for that matter) be managed better in order to reduce/eliminate constant airflow blowing at or in-the-vicinity of the print?
I think so. Enter the E3D V6 hot-end (and clones).
THE DESIGN GOALS
G1. Maximize the cooling efficiency of the heat-sink without resorting to a bigger fan.
G2. Reduction (or elimination) of constant airflow to/from the build area as a consequence of actively cooling the heat-sink.
G3. Minimize the offset from the stock nozzle position to maintain the maximum possible build area, without resorting to unusual mounting solutions/tricks.
THE DESIGN SOLUTIONS
S1. A straight-through airflow path through the heat-sink made possible by an innovative side-port design.
S2. Active cooling of the heat-sink is achieved by a pull-fan configuration, with a nozzle-directed exhaust.
S3. Y-axis offset (the only axis that must be shifted given the greater depth of the V6 hot-end) is minimized, with only +0.4mm (stock nozzle diameter) of wall thickness separating the heat-sink cavity from the X-axis carriage.
THE CAVEATS
C1. The mount isn't magic, and won't solve all your warping problems. But does work better. Hell, I like it because it's mine. :)
C2. The exhaust-end of a fan is noisier than the intake-end. That's the open end that more-or-less faces you. If you feel that the stock fan is noisy... then this isn't going to make it better. Just the opposite.
C3. I have made no provisions for attaching a print cooling fan and duct. Note that I do plan on designing an appropriate one in the near future. That said, I will make no promises, which is why I did not even include an attachment boss in the current design (and when I do, it will be on the bracket, so the extra print should be minimal). You should not utilize this mount unless your primary printing task is ABS or materials prone to warping.
PRINTING NOTES
Any hot-end mount needs to be printed in a higher-melting-temperature material, such as ABS or PETG. This one is no different.
The parts were designed to be printed in the orientations provided. You will probably benefit from full supports, and brims might be necessary for ABS. In ABS, I have found that the mount body benefits from scaling-up the X-axis by 2% in the slicer, while leaving the other axes alone. Neither the bracket nor nozzle requires scaling in ABS, and hence can be printed together. Otherwise, the dimensions of the design are accurate so that it can be printed in other materials that might not require any scaling, or different scaling (PETG, nylon?).
You will need 2x counter-sunk 3mm x 25mm bolts, and 2x 3mm nuts. Metric, obviously. Hex or Phillips head, your choice.
You will need 2 of the square nuts that are part of the Monoprice Select Mini hot-end and heat-sink assembly (there will be 4 from the disassembly for you to utilize).
The counter-sunk holes on the bracket can benefit from a little reaming with a countersink bit. But if you don't, it'll still be okay.