by TutherJay » 2013-Oct-Thu-14-Oct
So this appears to be the appropriate thread for continuing this discussion: PLA vs ABS (vs nylon) for replacement parts for some questionable wood structures that my PB+ v2 kit included - at least the best I've found in my attempts to search before posting...
I'm NOT pleased w/ the built-up layers of plywood for the carriage. After relatively few print jobs completed since original assembly I discovered an alarming amount of slop in the hot end - primarily in the Y-axis direction (much more than in the X) and further examination disclosed that it's not JUST the UBIS end mount into the wood structure that's the problem - it's ALSO that the linear bearings on the X rods (primarily the lower of the 2) were not gripped securely by that sandwiched LC ply arrangement. I've posted elsewhere about my serious questioning of trying to screw multiple wood layers together where all but the LAST layer are not drilled out enough so that they do NOT grab threads - anyone who has tried assembling wood thusly should have quickly discovered how that's problematic!!! Oh well - I digress - back to the topic at hand:
Just what is working out there in reprap land where working printers can THEORETICALLY replicate their own parts - as in what plastic works for what pieces? Of primary concern to me, as all I have to print with (so far) is PLA (PBHQ didn't have any ABS when I first ordered, so I had to settle for PLA and haven't yet ordered anything else from them or anyone else), is the structures supporting and in close proximity to the hot end. Can PLA stand up for the extruder and fan bracket, for instance?
While I have mine torn back down I may as well start asking, I finger. I'm going to TRY a couple quick fix things to see if I can stabilize this, but I want to print replacements ASAP if PLA will work. My batting average so far is abysmal - it seems that I get about one decent print job, whatever it is, after a real serious tune and adjust session, and then it botches things up again. Usually it's lost its Z awareness and either tears up the tape or doesn't touch down to deposit from layer 1 (this morning I awakened to find that almost nothing got on the print-bed - it had just collected a big mass around the hotend. I had found one successful print and tried to start another before I hit the rack last night, and YES, I DID recheck bed level at all 4 corners before the run. So after clearing off the big blob and relevelling, I tried again but all of the parts (all cylindrical) came out WAY weeble-fleeble (unround) upon do-over. At least they were ON the bed, not on the hotend.
So - what's the general consensus on material for replication???
(while I go back to reassembly. This took so long I don't even have the patience now to try to find discussion of how to tighten the loose UBIS end mounting)
Cheers
jm
TutherJay
PrintRbot+ v2 built from kit, hatched Sept 9, 2013
PowerTower & RPi/OctoPrint kits added
Repetier/Slic3r mostly; sometimes RPi:OctoPrint
1.75mm via direct drive gear head extruder
(temporarily abandoning Bowden mod - Bridge wouldn't fit thru)
E3D v5 hotend w/ Volcano Eruption upgrade
Stock LC ply bed now adjusted by 3 points, not 4
6mm heated glass (non-borosilicate) (now missing divot from BluPrint adhering TOO well)
<sigh>