CR-6 SE X Axis Cable Chain

thingiverse

UPDATE 15 Jan 22: Major update of the entire cable chain solution. The complete solution is optimised for the BMG extruder combined with the stock filament runout sensor. However, I have included a number of different options of some pieces (shim, cable chain anchor) that can be used with various alternative setups. Hopefully, you will find a combination that works for you. You will need: 3 x M3x40mm hex socket head screws. (The BMG extruder is delivered with non-standard 38mm screws, so this solution is designed to work with standard lengths.) 2 x M3x8mm screws (or any short M3 screw) for the shim - optional. (This is to fix the lefthand side of the shim in the holes for the stock placement of the filament runout sensor, but you don't actually need them - the shim is held in place just fine by the extruder.) 2 x M3x8mm flathead (countersunk) screws to fit the X carriage cable chain mount to the X carriage body. Depending on your personal setup, you may need to extend the runout sensor cable. Mine was like 2mm too short, so I had to get a couple of JST-XH female connectors and make a new, longer cable. SHIM The shim raises the whole extruder side of the solution up a bit, to be more in level with the hotend side. Also, some people worry that the Z rod bracket might come into contact with the drive gear of the BMG extruder. Even though I don't have that problem, a shim will eliminate any such worries. NOTE! All shims are 5mm thick. If you use one, remember to raise the drive gear on the stepper motor shaft a corresponding 5mm! There are three different variations of the shim: Shim with runout sensor holder for BMG extruder This is the shim for the complete solution - it has a connector for the cable chain anchor and a holder for the filament runout sensor integrated into the shim in one single piece. You will not need the old screws to reconnect the sensor - the holder is designed to be a snap fit. (If you want to take the sensor out of the holder again, pry it out by inserting a small screwdriver under the bottom by the connector cutout. If you only pull on the top, the top might pop off, sending the internals raining all over the floor. Ask me how I know...) Shim for cable chain anchor This is just the shim with the connector for the cable chain anchor, in case you dont use the filament runout sensor, or if you have another solution where you would just like to raise the extruder and connect the cable chain. Plain shim This is just the shim with nothing extra, just to raise the extruder and stock runout sensor. CABLE CHAIN ANCHOR This is the piece where the first link of the cable chain connects. The anchors are designed to fit tight over the connector on the shim with absolutely no play at all. If you use an anchor that is designed to fit with a shim, you won’t need to secure it further. However, all anchors are also designed with a hole for an M4 screw in case you want to use only a particular anchor without a shim. (In that case, do yourself a favour and use a buttonhead hex screw and screw it almost all the way in before fitting the anchor, since it is a bit fiddly to reach with anything but a hex key to tighten it the final turn or so.) There are three different variations of the anchor: Cable chain anchor for BMG extruder This anchor fits over the connector on the shim. Fit the anchor to the shim first, then slide the combined pieces in place before you screw the shim in place. Filament guide with cable chain anchor If you're using the stock extruder setup and just want a place to anchor the cable chain, this is for you. Plain cable chain anchor for BMG extruder An anchor for use in setups where you have only switched out the extruder to a BMG, and you're not interested in using the shim or filament runout sensor holder. LINK You will need 16-17 links, depending on how tight you want the chain to run. (I started out using 17, then I accidentally broke a link during all my testing, and found out that 16 work perfectly well. As a matter of fact, I prefer the tighter chain.) LINK COVER An equal number to the number of links. If you want link covers at the very start of the chain, fit covers on the first two links before you connect the start of the chain to the anchor, as there won't be room to fit the covers afterwards. X CARRIAGE BODY These are designed to be as low as possible. There are two variations of the X carriage body: X carriage body with Capricorn holder This comes with an integrated Capricorn (Bowden) tube holder. This only holds the tube centered, it does not clamp on to the tube tightly. The tube is free to move vertically within the holder, so it does not interfere with the bed levelling. However, be aware that it is designed for a Capricorn tube (which you should already have bought anyway) - the stock tube will not fit. X carriage body no holder This is just the plain X carrigare body without the Bowden tube holder, for those of you who prefer having the Bowden tube loose. X CARRIAGE CABLE CHAIN MOUNT This mounts to the Z carriage body with two M3x10mm falthead (countersunk) screws. Be careful when mounting the first clip to the X carriage cable chain mount! Hold the cable chain mount firmly with your fingers on the outside as you squeeze the link in, and make sure it's the link that is squeezed inwards and not the mount outwards. I'll be keeping the original thing description below, for reference and background. - - - - - - - - - - - HEADS UP 12 Jan 22: There will be a major upgrade/update very shortly, in a few days or so. I just need to have new JST connectors arrive from Amazon so I can test everything before I post it. UPDATE 10 Jan 22: After feedback, I added a slight chamfer to the screw holes on both X Carriage bodies, to make it easier to drive the screws home. I fancied cghildreth's cable chain, but there were a few flaws in it. The most egregious one the sagging and the chain spontaneously coming loose due to the weight. This was remedied in the original design by adding a "Hot End Retainer Clip" to prevent the chain popping loose. But this is just treating the symptoms, not the problem. The real problem with both the sagging and the popping out of the links in the original design is due to the conical couplings. These create both a high amount of sag, and the coupling strength between the links is very poor. I have remedied this by changing the conical couplings to cylindrical ones. This both eliminates the risk of links coming loose (I promise - you will not be able to pull these redesigned links apart no matter how hard you try!), and it reduces sag to a nearly negligible amount. (I still constructed the links with a "quick-coupler" for easy assembly.) So there is no longer any need for any retainer clip. Next - in my own setup I also use Riddeen's vertical Y axis chain (https://www.thingiverse.com/thing:4786780). cghildreth's chain is mounted too far away from the gantry to fit behind Riddeen's y axis chain. So I remixed the Filament Guide With Cable Chain Link to fit inside the Y axis chain. I also moved it up as far as it can go while still allowing the arm of the extruder to go clear. At the other end of the chain, I lowered the X Carriage Body as far as it could go. There is still a couple of mm height difference between the two ends of the chain, but it is not a concern over the entire length of the chain. If anything, it helps to eliminate any (minimal) sag in the chain. I also redesigned the Bowden tube holder to fit a Capricorn tube better, and repositioned it to align with my Micro-Swiss all-metal hotend. If this doesn't fit your setup, just slice it off before you print it. (EDIT for clarity: The holder only keeps the tube upright; once you have clicked the tube into the holder, the tube runs freely up and down within it, and does not interfere with the bed levelling.) The original links are also designed to be able to "bend over backwards", which makes the chain go around in a big bend. I like a more "industrial" look to my chain, so on the one hand I redesigned the links to stay straight when the chain is flexed back, and on the other I redesigned the mounts on both ends to stay at a permanent 90 degree angle. The movement of the chain is so much more satisfying now. There were also some errors in the internal dimensioning of the link couplings that I have corrected to help the links move more freely. You will have to orient everything to lie flat in your slicer. The cable chain mount should be printed with the link tabs up top. You will need to print 17 links/closures, and one each of the others. You’ll need internal supports for the slot in the carriage body and the overhangs in the chain link mount. I printed the links with supports for the holes and the cylindrical couplings, but they may print without supports - I haven’t tried. The filament guide and link closures need no support. Be careful when mounting the first clip to the X Carriage Cable Chain Mount! Hold the cable chain mount firmly with your fingers on the outside as you squeeze the link in, and make sure it's the link that is squeezed inwards and not the mount outwards. The X Carriage Cable Chain Mount is mounted to the X Carriage Body with two countersunk 10mm M3 bolts. EDIT: I added a version of the X Carriage Body with no Bowden tube holder for those who prefer not using one.