New MPCNC for 2020! - Primo -

I personally think putting a water cooled spindle on is less than optimal. The extra weight requires slower movements, especially starting and stopping movement, which wipes out any gain you would get for having a stronger motor. The DW660 has plenty of power at the speeds we move and is a very good match for the rigidity of the MPCNC. No need to go to the extra expense.

Naa, it’s all out there. Getting the equipment to make good filament is expensive.

I am considering adding end stops to my upgrade. In the shop, Mostly Printed CNC’ there are 2 different types listed, end stops and roller end stops. Is there a preferred, one over the other? The roller is listed as a little cheaper. I think that they both have some advantages.

Either will work. Get a few extras. I usually end up snagging the lever and breaking it off the switch.

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Agreed that the tech is out there. I work at a mostly rubber company that makes mostly rubber products but we have a plant that makes mostly plastic hose and tolerances are not on the hundredths of a mil and sometimes that is even tough to hit.

Not that we have even remotely new lines/equipment doing this… It’s just hard to make something that a consumer could purchase that will make consistent enough filament for our consumer 3d printers.

82% done!

Just waiting on the full kit to come out! So exciting!

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If your goal was to start with plastic pellets or scraps along those lines, and print directly with them, then what would really help is a way to extrude and measure the molten plastic. If there was some kind of pump that would work on molten plastic, and precisely dose it at that point, while it was in a tube, you’d know how much volume you were extruding (assuming you could avoid bubbles), straight into the hot end.

I don’t know if such a thing exists, and can fit in your hand.

At one time I worked in the lab of a flooring manufacturer and we would extrude vinyl pellets through a screw type extruder that also melted the pellets. I wonder if an accurate measurement of flow could be calculated from from the speed of the extruder screw?

Extrude a bit oversize, then “inverse ream” (not sure if there is a term for that) after its cool and recycle the shavings. This would be stupid for industrial production but for home use should work and would be more achievable than tight process control.

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Little google-fu for you:

Pot broaches are cut the inverse of an internal broach ; they cut the outside diameter of a cylindrical workpiece. They are named after the pot looking fixture in which the broaches are mounted; the fixture is often referred to as a “pot”

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I am still printing, but does the build process require drilling into the tubing?

4 holes in the Z rails.

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Hobby-level filament extruders are very temperamental to run and doubly so with recycled filament. The smallest contaminant can/will clog your hotend, and any variation in the extruder’s behavior will give you variable filament diameter and possibly jam in the heatbreak.

There are direct pellet extruders, but they are generally for large-nozzle/high-flow situations https://www.youtube.com/watch?v=p3leeM1HHq8

I fell down this particular rabbit hole earlier this month so I’ve done a lot of watching/reading and would be happy to say more in another thread if people have more questions.

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If you write it, they will read

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There is a helper file you can print that has the holes in the right spots. I just like doing things overkill. The file is somewhere in this thread

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Great advice, what do you thing about 1mm nozzle? What layer hight - 0.5mm?
It will bring down print time also…

The problem with going too big is you might start loosing layer-level detail.

Some of the details on the print would get lost if you’re only doing .5mm layers instead of .3mm layers.

Recommended layer height is maximum 75% of nozzle size, if I don’t remember wrong. 1mm would give a huge height and speed improvement! I’m not sure if @vicious1 recommends such a big nozzle, since some of the finer details in the print will disappear. I don’t know the technicalities on this, let’s hope Ryan chimes in.

Edit: I have a 0.6mm nozzle on my prusa mk3s. It’s got built in settings, both in firmware and slicer for that size - super easy to use. I’m going for something around 0.4-0.45mm when printing starts. (Waiting for 25mm)

Bought some emt today, measured it’s 23.5 now I wait. Keep up the good work!!

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Not sure about a giant nozzle, It could work as long as you do not lose the bearing spacers embeded into the parts.

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