3D Printer Y Axis
This weekend, after receiving the hot end from my lovely wife as a valentine’s day gift, I dove back into working on the 3D printer. I have been buying parts for months, picking up lumber, smooth and threaded rods and basic screws, nuts and bolts. After sitting down and deciding to just put things together, mistakes were made. My initial thoughts had a design with a 9”x9” bed, however I forgot to take into account the location of the bed mounting blocks and now I am stuck with only 5.5 inches of travel in the Y direction! Lesson learned, measure five times, cut once!
So, after that minor disappointment, I tried to accurately measure and drill holes in the 2x4s with my drill press. This failed, I was off about 1/8” in the end, enough to bind the platform and keep it from traveling all the way. I explained this to my wife and she said I should pin the pieces together and drill them as a single piece, this was brilliant! I ended up clamping the ends and drilling through both boards at once, now I have parallel bars. I used hot glue to attach the nylon spacers, which I use as bearings, to the moving platform and then greased the bars with some white lithium.
I attached the stepper using a simple metal L bracket. On the other side is a slidding glass door bearing. Braided nylon fishing line was strung between both of them and wound around a wooden spool I fitted on the stepper motor shaft. I attached the electronics and I was able to get motion out of the platform! After measuring repeated moves and getting different answers I determined that the spool I created was not centered. This is a problem as an elliptical path will cause inaccuracy as movements can’t be reliably repeated. I asked for ideas on the #reprap channel on the Freenode IRC and received the following suggestion, chuck the spool on the drill press and use sand paper to make it properly round. I will give this a try. My next step is the Z axis!