======jit's build:  Y back end======

[[jitsbuild-x-rightend|Prev: X right end]] < [[jitsbuild| Up to Jitsbuild]] > [[jitsbuild-y-frontend|Next:  Y front end]]

//This page pertains to the Bukobot v1.  Some portions may be useful to v2 owners.  For more information, see [[jitsbuild|here]].//

=====Parts=====

Parts in [[bukobot-parts-list#y-end-back-motor|bag 12]].

{{wiki:jitsbuild:y-backend-kit.png?800}}

Shown here is the Y back sub-kit, plus a stepper motor, its synchromesh pulley ([[bukobot-parts-list#synchromesh-cable-system|bag 11]]), the Y endstop holder and its two M3x10 button-head screws, and some hardware from the endstops kit ([[bukobot-parts-list#endstops|bag 5]]).  At the upper right are the endstop switch with a M2.5x16 socket-head screw and nut, but that's wrong;  it should be two screws and no nut.

=====Install Screws=====

Check that the two M5 screws slide easily through their holes.  Widen if necessary.

Check that the M5 nuts fit into the gaps in the long tabs that will later slide into the extrusion slots.  If the gaps are almost but not quite wide enough, resist the urge to pound the nuts in.  A better solution is to insert an extra-long M5 screw through the hole, screw the nut down onto it until it touches the plastic tabs, line up two flat faces of the nut with the plastic, and tighten the screw to drive the nut down into its niche.  If you need to use a lot of force to do this, don't;  remove the nut and screw and apply a file to the niche, then try again:

{{{{wiki:jitsbuild:nut-niche-widening.png?800}}

Install the M5 screws and nuts, and tighten them down.  You will have to loosen them later to install the extrusion.

=====End Stop=====

Next, assemble the endstop subassembly:

{{wiki:jitsbuild:y-endstop.png}}

Note that it uses two screws and no nuts.  The holes in the printed part may need widening, but do it carefully as they need to hold threads.  The smaller of the two holes in the switch will likely need widening with a 2.5mm drill in order to allow the screw to fit easily.

If you manage to break the wires off the switch while assembling it (happened to jit's build more than once), make sure you reconnect them correctly.  Miswired endstop switches can cause havoc.

If you ever have to reconnect a wire on an endstop switch, put heatshrink tubing on the wire before you solder it, and then shrink it onto the terminal.  This will make it less likely to break the next time you work with this endstop.

=====Finish Assembly=====

Once the endstop is done, finish assembling the Y back end.  As before, you may wish to leave the endstop unattached until later.

Top view:

{{wiki:jitsbuild:y-backend-topview.png?800}}

Bottom view:

{{wiki:jitsbuild:y-backend-bottomview.png?800}}

Set this aside.

[[jitsbuild-x-rightend|Prev: X right end]] < [[jitsbuild| Up to Jitsbuild]] > [[jitsbuild-y-frontend|Next:  Y front end]]

//The contents of this page may be re-used under any of the following licenses:  The [[http://creativecommons.org/licenses/by-sa/3.0/|Creative Commons Attribution-ShareAlike 3.0 Unported License (CC BY-SA 3.0)]], or the [[http://www.gnu.org/copyleft/fdl.html|GNU Free Documentation License (GFDL, version 1.2 or later)]].  Nothing on any of these pages is there to tell you what to do, only what other people have already done.//