learning. this is why I am building a very old design 3D printer. as I work with the parts and the instructions my eyes are widening. I am seeing what is wrong with what I have. this allows me to fix what is not working. or go in a different direction.
it seems that molded mendal uses a large sized bushing. to use these parts with smooth rod would mean replacing the rods I have with a larger diameter. a move that fixes a design flaw. however, this is just one way to fix a flex problem. I decided I am not going to replace all the rods to accommodate these parts. this means switching to bearings, reprinting parts to use smaller bushings, or make smaller bushings that will work with the parts I have. hmm… ugh. decisions. right?
the parts that I have are actually very poor in quality. I would not have known this until I started the build. it is that “seeing stuff in context” that kicks in. what was “cool looking” turns into “oh what is this what the what!” the X axis pieces do not fit together and will not ever unless I do a lot of rework. the extruder plate has problems. and how do I work bearings into this mess? I guess it makes sense to try to fix what I have. to make it work. try anyway. remember the idea is learning.
but try as I might I see certain failure already. the extruder plate is cracked on one side. maybe when I add the stepper motor to the plate it will reinforce it making that crack not matter. or the crack will get worse as I try to mod the plate to use bearing instead of bushings. it needs to survive adding 16 large holes for zip ties to secure them. will that be strong enough? will it warp or bend as it is pulled by the belt? in reading about the Prusa warping seems to be a problem in this area. remember, the drill does not like resin.
the other axis parts have similar issues mostly do to the sloppy nature of the molds. the rod holding plate will not fit unless it is sanded, cut, or mashed together. the drill hates this stuff shatter or tear parts as I work with it. specifically, it is the stiffness of the resin that makes the outcome of any mod look dubious.
to move forward I am going to do two things: rework the parts and order replacements.
these two parts found on thingyverb fix my plate and axis problems. note that that work with bearings fixing the rod problem. the two axis parts do not use a pressure plate to hold the rods solving that rework problem plaguing the molded pieces.
[story about 3Dhubs goes here]