Hi guys, I've quickly sketched up a lead screw corexy based on the digital dentist's design just to see how things will fit together. I've built a d bot before, but this time, I want to start off a build from scratch and try to get everything right. I have a few questions regarding the mounting of lead screws. I'm considering a triple lead screw setup (20mm diameter lead screws because it costs tby nkewong - CoreXY Machines
Is there a reason you cut a little bit of the tubing next to the pulleys on the pulley assembly? There should be enough clearance for the belt, right?by nkewong - CoreXY Machines
A question about how you mounted your x axis linear rail to the aluminium tubing. Did you drill an extra hole? Also, any issues on the x axis linear rail flexing?by nkewong - CoreXY Machines
I bought 20mm lead screws for my 400x400x744mm build. However, with some calculations on the column strength, 10mm should be sufficient for my application (if mounted properly). The reason I went with 20mm is because it costs about the same as 10mm or 12mm lead screws and I was more concerned about the lead screws getting bent on the way to me than anything else. This answer probably didn't helpby nkewong - CoreXY Machines
Very nice! What are plates are you you using for your y axis? I notice that you don't have any extrusion underneath it for support.by nkewong - CoreXY Machines
Do you have issues with flexing with your Hiwin AG20's on the x carriage? They're significantly smaller rails than what the digital dentist is using. I'm planning to do a similar build and am looking at the EG20's.by nkewong - CoreXY Machines
Quotethe_digital_dentist No specific reason - I had some left-over pieces and didn't have any smaller stuff. Since there are no lateral forces on the bed smaller extrusion should work OK. I wasn't too worried about the weight- the Z axis drive I used can handle a LOT of weight. I see. Which bearings did you use for your pulleys? On your blog, you wrote F6902zz but elsewhere, I read F6903zz.by nkewong - CoreXY Machines
Is there a specific reason you used 4040 extrusions for your bed? I'm thinking smaller aluminium extrusions can be used to reduce weight.by nkewong - CoreXY Machines
Interesting thing you've done with the pulleys. Did you just stack a bunch of bearings instead of using two flanged bearings for one pulley?by nkewong - CoreXY Machines
Quotethe_digital_dentist I think constraining all four corners of the bed support is likely to end in the mechanism binding at the slightest misalignment. Two bearings should be enough if everything is perfectly inflexible, so three should be plenty in the real world. Belts vs lead screws is a personal choice. Belts look like a cheaper alternative initially, but when you solve the bed-drop pby nkewong - General
With the z axis linear guides, I'd probably do it the way you did, which is by milling the t-slot extrusions such that I have a flat surface to mount it on.by nkewong - CoreXY Machines
Have you considered the volcano hotend? It seems like a good hotend considering how big your machine is.by nkewong - CoreXY Machines
I'm looking to build a 400x400mm bed with the linear guidance in the z axis using mgn15 rails. I'll build the whole thing in 4040 aluminum extrusions.by nkewong - CoreXY Machines
Hey guys, I'm looking to build a corexy with three 10mm (diameter) lead screws. The build height will be tall, at around 700mm. What are your thoughts on 10mm lead screws? Should I use a belt drive? Maybe ball screws?by nkewong - CoreXY Machines