Random notes as a slow starting Repeat builder-
I’m still working through learning Fusion 360 and was thinking of building using 2020 extrusion and targeting a 300x300 bed setup. I don’t mind the learning at all- but it is mildly frustrating that there isn’t a reference build in a common size like 300x300 that could be followed without going through that learning curve.
This plus working on calibrating my TAZ has effectively stopped my build after printing the PLA parts.
The belted Z is one of the great things about the repeat, but I was dreading the attachment and tensioning.
For direct drive with less mass, the H2 as you use is good, as is the Orbiter extruder. I’m finishing a BMG with a pancake stepper and E3D V6 on my TAZ, and it’s 1/4 the mass of the original extruder. Amazing.
For a larger volume repeat, a setup like the BMG X2 might be worth having if someone wanted to use dual extrusion. I’ve been wanting to use dissolvable filaments for a while and some option for a dual extruder on the repeat would be good.
I would love an option for a quick change hotend like the E3D Revo or similar,.
I’ve decided for my use case a 300x300 heated bed will be the size. I was just looking at the various common heatbeds in this size, and an option for a ‘stock’ build using a commodity heated build plate would be good for new builders. I hate that so many of these use 4-point mounting. DUMB! (Giving my TAZ a dirty look as I think about that- it’s the same way.) Easy to put 3 points into a plane. 4 points just leads to infinite ways to warp and deform the print bed.
I realized at the larger build volumes that .4 and even .6mm nozzle sizes don’t make sense for me- I’m wanting to go with a .8 or even 1.2mm nozzle on a high-flow hotend and will run .5mm or larger layer heights for many of my prints. Something to perhaps think about when designing parts.
I have access to machines with smaller nozzles if I should want to print something with fine detail, but for production use like what I imagine your own print farm does, those higher material flow rates seem pretty tempting.
I just fell down the rabbit hole of calculating flow rates as I’ve been trying to get my TAZ better calibrated. As I’ve been working on that it’s been amazing how much faster (in theory) larger parts can be printed with the higher flow rates on larger nozzles. I know that CoreXY allows faster motion, but for production use of parts like those you design, optimizing for a larger nozzle looks like it would make your print farm operations faster and more efficient. It wouldn’t hurt strength either to have thicker parameter walls.
I was wanting to do something better on my Repeat build for wire management. Everything else about V1 machines are so wonderfully well thought out, but wire management seems to be the most difficult thing for builders like me to get right. I build spacecraft, so my expectations for wire management are absurd- and I seldom meet my own expectations on my own personal builds.
As a note, Klipper firmware just recently added support for CAN, including cheap RPi Pico boards with CAN transceivers- so I’m really thinking I’ll want to get my build done with Klipper (Will be my first Klipper machine). Eventually I think we’ll see more use of CAN and something like USB-C for power delivery and communication to toolheads as reducing wiring count and connection types seems like a good idea.
I think a revised repeat should just use linear rails on all the axis and forego the CF tubing on X. Might even open up the possibility of using a compatible extruder mount to other coreXY machines that are using linear rails on X, which would allow more extruder combinations.
Finally, one of the really great things about V1 machines is that you provide source for the designs and support your builder community. Thank you for that. It’s really nice that you reach out for reviews, when so many today are completely deaf to user feedback.