I have two nice 9mm smooth rods salvaged from old Epson printers and I would like to use them for my new boxed-frame Prusa i3 (using my DIY brass nut bushings). So I was searching for suitable Y-corners. Instead of the zip-tied originals, I prefer the capped type, like the one published by ch1t0. But unfortunately, those are only provided as STL files, so they are not easily reconfigurable.
Also, when looking at this and various other versions of Y-corners, I found that, while the rod diameters are usually given, it is not so easy to get to know the distances between the rods and there height above ground. But these parameters are equally important to have the corners fit with the accessories (e.g. y-stepper mount) and the specific frame construction.
So when finally ended up writing my own SCAD code for the y-corners, I chose the main parameters to be the diameters and the center heights above ground for each of the four rods. As an additional parameter, the diameters of the corresponding washers cut-outs can also be specified. All these parameters are specified as arrays with 4 elements, corresponding to the rods from the lowest to the topmost.
The caps are mounted onto the base corners by means of two M3x12mm screws and the corresponding screw nuts.
STL files are provided for the following rod configurations:
- 8mm smooth, 10mm long threaded and 8mm short threaded, at heights 10/20/30/45mm (this corresponds to the standard Prusa i3 corners)
- 9mm smooth, 10mm long threaded and 8mm short threaded, at heights 10/20/30/45mm
- 10mm smooth, 10mm long threaded and 8mm short threaded, at heights 10/20/30/45mm
- all rods 10mm, at heights 14/25/36/50mm
Each of the above configurations STL files for 1 and for 4 corners are provided. The file names contain the rod diameters and center heights from bottom to top rod.
If you need any configuration other than those provided in the STL files, simply modify the corresponding parameters in the SCAD file and regenerate your specific STL file.
Update 2014-02-25: Just uploaded a slightly improved version which has support layers above the nut cavity and the screw head cavity. This allows for cleaner printing.
Update 2016-02-13: If you need a motor mount for you Y-frame, check out my Easy Change Split Y-Motor Mount which can later on easily be removed and replaced without disassembly of the Y-frame.
The source code in the SCAD file is pretty self-explanatory. As an illustration, here is the call to the ycorner() module for producing a Y-corner for the standard Prusa configuration:
The height and diameter parameters specifies the center height and the diameter of the 4 rods (bottom up), the washer parameter give the size of the washer impressions (0 for the smooth rod implying no washer) and the finally the width parameter gives the X-/Y-size of the corner block. The abt parameter is used to specify which part(s) of the corner to build: 0=all (not for printing!), 1=base only, 2=cap only (in print position). Other parameters that can optionally be specified are: top (the thickness of the cap, default=3mm) and gap (the missing slice between cap and base which allows good tightening of the cap, default=0.5mm).