Ok, so sometime last week I was messing around and realized that I could totally eliminate a bearing from the printer. The realization was that the pulley inner circumference was a tad bit over 8mm, so a M8 rod could go right between the belt if everything lined up just right. Well it took up until last night to fully get this idea to work.
There were three main issues in designing this. The first was that I had made a minor mistake on the hole spacing, which was easily corrected. the second mistake or issue was creating the supports. I still honestly do not know If I totally like the amount of support on this mount, but it is exactly how I imagined it. I imagined it being simple and using little material. It flexes a bit, but I made the “beefyness” parametric, so I could easily increase it later.
I am going to start a new paragraph on the third issue, because it was BIG. It took me a few nights to figure out why my mount was not fully working. It ultimately came down to my OpenSCAD code being right, I just did not fully understand how the vertexes were parameterized. To imagine, on the vertex, there are 4 rods entering it. when you set the angle to 60 degrees, only 3 of the rods can be contacting. the fourth needs to be angled slightly, so it is only in contact with the horizontal rod. The horizontal rods and the two rods going in the Z direction create a 45 degree angle. If you do not have the correct vertex for each corner, this will be confusing, because the two X direction bars make a very slight angle.
Long story short, each vertex has a specific corner. And I am just about done with my Y axis. Some pictures for the end…
S. J. Kelly 