3kg print head anyone?

  • Here is a link to a video of the latest evolution of my CoreXY https://youtu.be/5RptHCX7z0o

    Alternative titles - "How to mount three extruders on a 600mm x 600mm x 1000mm frame and keep the Bowden tube length down to 170mm"

    or " Why you probably don't need Nema 23s as 17s will do just fine".

    I'll do a full write up on my blog but right now, this is a really busy time of year for me so it'll have to wait.


    Edit. What do I call this printer - CoreXXYY ??

  • administrators

    nice! one of the thinks I like about your printer (along with the obvious awesome construction and innovation with the diamond) is how quiet it is, you have your fans dialled in well.

  • Thanks Tony. Yes, though I say so myself, it's not too scruffy considering that it's lugging over 3kg of print head around (including all the extruder steppers, rails, pulleys, cable chain, etc). Actually, because of the very low friction, it takes very little effort to move the parts. I did a test on the triple extruder carriage assembly which weighs in at 950 gms. Using a pulley and kitchen weights, it only took 60gms to move it along the length of it's carriage. Of course, accelerating a mass is another thing altogether. One advantage of the mass is that "ringing" is non existent - it's simply too heavy to resonate.

    Of course, it's your fault (that is to say the entire Duet team) that it's so quiet. The stepper drivers started it, in that the motors are so quiet that fans started to become intrusive. So I changed the PSU for a fanless version, then stuck thermistors in various places and used spare pwm channels on the Duet/Duex such that all fans only run when needed. At idle, it is virtually silent - just a very faint buzz from the steppers at 30% holding current which is inaudible at anything more than a couple of feet away. The noisiest thing is the hot end fan but it has to be very high flow rate so their isn't much I can about that.

    Also, all the carriages use Open Builds Delrin wheels running on V slot which are practically silent too, which helps a lot.

  • Very nice setup Ian…I plan to use a similar overhead gantry for the extruders on my machine. The length of drag line cables on yours confirms what I thought would be about right for mine.... Keep posting, I enjoy your blog too.

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