As linked to in Mechabits' reply, I'm (slowly, LOL!!) building a CoreXY with a welded frame. What you say is true, a welded frame will be very rigid, and will be less susceptable to losing it's "square-ness". What many don't realise is that the process of welding introduces a lot of movement in the metal that you're welding, so it can be increasingly difficult to keep the frame square and true wby TE78 - General
A piece of Ali' angle was suitably cut into 2 sections to make up the Stepper Motor brackets for the X & Y (or A & , and was milled out to accept the Stepper shaft and also drilled for it's mounting screws. A couple more milling operations gave it the required shape for mounting onto the side uprights, and a couple of M5 clearance mounting holes were installed. Then those mounting holes wby TE78 - CoreXY Machines
So after a few iterations of one part, I've got the bed mountings made and put into place. No doubt the wisdom of those much more experienced with 3d printer building will point out the flaws in this design, and no doubt this may get changed/developed further, but here is where I am at the moment. As mentioned before, I have incorporated the actual bed-levelling adjustment screws into the Z-axisby TE78 - CoreXY Machines
Thanks for taking the time to look and comment, Quotecozmicray Please get some socket head bolts and a set of hex drivers Phillips head screws for wood working (maybe) I may well replace the screws with socket head bolts, but for this stage these seem to be doing the job quite adequately, and I have plenty of these already in stock. Is there an advantage of socket head bolts over pozidrive?by TE78 - CoreXY Machines
Thanks for that hint MKSA, I'll try to remember that one. So a little more progress to report. I took each of the leadscrew's off and straightened them so that they are running true with less than 0.5mm "wobble" at the end of one screw, and less than 0.2mm with the other 2 screws. (I could've spent much longer on it to get even less runout, but it seemed to be diminishing returns, and I was hapby TE78 - CoreXY Machines
Well, it's amazing how life can get in the way of building a 3D printer!!! So after quite a long break from this project, I've been getting back into this again. There's not a huge amount to show from the last few weeks, but I've been getting a few small items ticked off the "to-do" list. Here's a shot of where I'm up to at the moment, I've been working on the Z-axis which is based on 3 leadscrby TE78 - CoreXY Machines
QuoteQdeathstar Looking pretty skookem. What kind of mill do you got? I really want to get one... was debating between a grizzly or a pm.... with power downfeed and dro. I doubt I'll want to go cnc Thanks. I have a little sieg x2 that I converted to CNC, although I mostly use it in "manual" mode by using a jog/shuttle wheel to control movement. I'd say definitely go for the DRO's they'll make aby TE78 - CoreXY Machines
I managed to grab a few mins in the workshop today and drilled and tapped for M6 grub screws to grip the 8mm ground rods. Then I drilled and tapped some M3 holes to hold the 12mm linear bearing in the carriages. (I drilled/tapped 1 hole at each end, carefully positioned so that the M3 washer is just protruding over the edge of the bearing) View of the M6 holes (I counter-bored 6.2mm to a deptby TE78 - CoreXY Machines
That's very true Floyd, it was essential on this build as some of the ball-raced-pulleys are only 3mm bore. That would be a bit bendy when the belts were tensioned. I got a little time in the workshop and started by drilling some oblong holes. (now I know why square drill bits are so expensive, but they would have saved a lot of sweat and effort with drills & files) This might make it aby TE78 - CoreXY Machines
I got the brackets made today, just a couple of 8mm x 10mm x 43mm scraps of ali, with a slot milled in it to accommodate the upper bearing. Not much, but some forward progress. Timby TE78 - CoreXY Machines
QuoteQdeathstar Looks nice. Lots of machining. . Why did you decide to go with shafts instead of rails? Thanks, it was simply a case that I already had the shafts and bearings. If they prove to be unreliable or inaccurate, it shouldn't be too hard to change over to rails (famous last words!! ) Timby TE78 - CoreXY Machines
I got a little more done today (emphasis on "little"), I tapped the 3 holes on each carriage M3. Then I made the pin that will screw in to hold the ball-raced pulleys. The plain pulley has a bore, or rather, the bearing in the plain pulley has a bore of 3mm, whereas the bearing in the toothed pulley has a bore of 5mm. So I turned up a stepped pin with a short section of M3 thread on each end, thby TE78 - CoreXY Machines
A little more progress made today. I started working on the Y-Carriage blocks to whittle them down a bit for mounting the bearing-pulleys for the belts to run round. So I milled off a "T" section, drilled for tapping M3 for mounting the bearing-pulleys (the centre hole) and drilled two holes 15mm either side so that I can make a little bracket to fix the top side of the pulleys. Another viewby TE78 - CoreXY Machines
QuoteNice and chunky where it matters. I like it! Thanks, but it will get slimmed down once all the essential engineering is done, corners will be either rounded or bevelled, all to shave the weight down as much as possible. Quotethe_digital_dentist Are the X axis rails locked down in the Y axis bearing blocks somehow? If not, when you apply belt tension the Y axis bearing blocks will try toby TE78 - CoreXY Machines
A little more progress to report. I've made up a couple of Stepper Motor mounts to be welded on to the frame, but I'm glad that I didn't weld them on as I've changed my mind on how I'm routing the belts ( I may change it again as the project progresses ) But I acquired a short length of 37mm square ali bar which I hacked off a couple of shorter lengths to make the Y-Axis ( I think ) carriages,by TE78 - CoreXY Machines
Yea, there's no substitute for experience, which I don't have any in building 3d printers!! But I'm reading as much as I can find and trying to learn from the experience of others. I have thought about the hotend being offset, and how the X-axis carriage size reduces the working range by the same amount of it's dimensions. I will wait until I've built the X-axis carriage before starting on the Zby TE78 - CoreXY Machines
Quotethe_digital_dentist How did you manage to drill the holes in the frame so they are properly aligned and will allow your cam to position the guide rails parallel to each other? What did you use for a reference for the measurements? I drilled the holes before I welded the frame up. I set up a vice-stop in my mill so that each upright would be positioned the same place, and then using an edgeby TE78 - CoreXY Machines
1st post, but been reading on here for months before registering so I could share some of what I'm up to. My name's Tim and I've been into model engineering for a few years. This will not be a quick build as workshop time is limited, I've already been pecking away at this for over a month to get to where I am today. For quite a while now I have had the urge to build a 3d printer, reading aroundby TE78 - CoreXY Machines