**jit's build: Y axis** (Go back up to [[jitsbuild|jit's build]]) Find these: {{wiki:jitsbuild:y-axis-subassemblies.png}} The three metal parts on the left will be shorter if you have a 5" model. Start with the Y front end (the printed part without the motor). Loosen the two M5 screws until the nuts are flush with the ends of the screws, and then loosen them a bit more (but not enough so that the screws fall out of the nuts). Insert the aluminum extrusion the only place it can go (check image below for which end to use) and slide it all the way in. You may have to adjust the height of the nuts to clear the edges of the channel. When the extrusion is fully inserted, tighten the screws. Do the same thing with the Y back end. Be careful that you don't damage the endstop or its wires, if you have already installed it. Bottom view: {{wiki:jitsbuild:y-axis-bottomview-norods.png}} Top view: {{wiki:jitsbuild:y-axis-topview-norods.png}} [[wiki:clean-and-lubricate|Clean and lubricate]] the two steel rods. Pop two linear bearings out of their holders on the Y carriage, and insert one of the rods through them. Move the bearings apart a bit; you can use them as a handle when handling the rods in the next step, which helps to keep the rods and your hands cleaner. Do the same for the other rod. Install the rods under the fender washers, using whichever technique works best for you. You may have to loosen the fender washer screws; don't lose the nuts on the other end. {{wiki:jitsbuild:y-axis-withrods.png}} Loosen the bearing holder screws a bit on the Y carriage, so the holders can be rotated. Snap the carriage in place, and check that it moves smoothly: {{wiki:jitsbuild:y-axis-nocable.png}} Peek under the carriage and check that there is plenty of clearance between the bottom of the tensioners and the aluminum extrusion. Make sure all of the linear bearings are fully inserted into their holders. When everything is well aligned, carefully tighten the holder screws without rotating them. Check once again that movement is smooth. Next, we install the Y axis synchromesh cable. Get one of the synchromesh cables, and find that last tiny part from the Y tensioner sub-kit. Remove the Y carriage, and turn it upside down. Place the small semicircular Y tensioner on the end of the Y tensioner screw, and retract the screw until the Y tensioner is fully retracted: {{wiki:jitsbuild:y-tensioner1.png}} {{wiki:jitsbuild:y-tensioner2.png}} {{wiki:jitsbuild:y-tensioner3.png}} At this point, pick up the carriage by one rail and let the carriage, and the big loop of cable, dangle. The big loop should be flat. If it is pretzel shaped, or saddle-shaped, then it is twisted. Pull the cable back out of the part on the right and take the twist out, then re-insert it. The cable should be dangling in a plane. Insert the free end through the last tensioner hole, leaving a loop big enough to grab: {{wiki:jitsbuild:y-tensioner4.png}} Snap the carriage onto one rail, as shown below. The carriage will be acting as an outrigger and will try to tilt the whole arrangement over, so support the far end of the carriage with some object. Arrange the cable as shown. {{wiki:jitsbuild:y-tensioner5.png}} Take the slack out by pulling it through the tensioner into the smaller loop. Make sure the cable goes onto the two pulleys; you only need enough tension right now to keep the cable on the pulleys. If the smaller loop gets out of hand, shrink it by pulling excess cable through the tensioner; the free end of the cable will be getting rather long by now. {{wiki:jitsbuild:y-tensioner6.png}} Rotate the carriage over and snap in the two remaining linear bearings. Make sure all four bearings are fully seated. Take in more slack, keeping the cable on the pulleys. Peek under the carriage and make sure the cable is still seated on the small semicircular part. Carefully examine the synchromesh pulley (on the motor) and make sure the helical winding on the cable is lined up with the matching indentations in the groove of the pulley. {{wiki:jitsbuild:y-tensioner7.png}} The tensioner parts need to be adjusted in the X direction (up and down in these images) to make the cable parallel with the steel rods. (However, the portion of the cable between the two pulleys doesn't have to be parallel with anything.) Loosen the three screws (the ones shown here with three washers under the head of each) just enough so they can be slid along their slots. Slide each tensioner along its slot until the bit of cable between that tensioner and its nearest pulley is parallel to the steel rods. There is a groove in the aluminum extrusion that can be used as a guide, as the groove is already parallel to the rods: move your head until the groove lines up with the cable. Adjust the tensioners in this way, then pull on the small loop to tighten the cable some more, then adjust the tensioners again. {{wiki:jitsbuild:y-tensioner8.png}} Tighten the three screws. {{wiki:jitsbuild:y-tensioner9.png}} {{wiki:jitsbuild:y-tensioner10.png}} {{wiki:jitsbuild:y-endstop-set.png}} [[jitsbuild-yaxis|Next: Y axis]] //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)]].//