Kossel Wire Cable Frame Braces 2025 - Remix

I added clearance to allow the use of M4 T-nuts. I recommend printing in the orientation the STL files are in, with tree supports (on build plate only) and a brim. 

I used the following print settings:

• 0.4 nozzle

• 0.2 layer height

• 5 walls

• 6 layers top and bottom

• 40% infill using gyroid or cross hatch

*I increased the size of the double-eye part size by 141.24% (in all directions) and included it - this makes it easier to feed the steel cable through the small holes.

For the hardware, I bought this M4 kit and this M5 kit from Amazon.

If you like my designs and want to send me a tip, you can do so via PayPal….. Thank you and enjoy the models I create.

From the original creator, Kiolia:

“Turn your Kossel from a wobbly tower that rings like a bell into a rigid, no-nonsense, crisp-printing etc. etc. etc. thing of awesomeness with these snazzy-looking anchors for steel wire frame braces and increase either your quality or speed/acceleration by a lot (or meet in the middle someplace), hurray!”

You'll need 3 each of the adjustable and fixed anchors, 3 of the screw adjust mounts, 6 clamp washers, and 1 double eye join, plus:

• 1/16" steel cable (about 4.5 meters for an AnyCubic Kossel XL, or estimate by taking your frame's top to bottom diagonal measurement times 6 + 10%).

• 3x M5x20 bolts (socket head)

• 6x M5x12 bolts (socket head)

• 9x M5 nuts

• 15x M4x12 bolts (socket head)

• 15x M4 nuts

• 4x wire clips (preferably the screw-on kind, not the permanent ones) to fit the wire

• Drinking straws in your favorite color

• Kapton tape or similar

Special tools:

• Wire clippers

• A ball-end hex key to fit your M5 bolts will make life much easier.

Assembly Steps:

1. Stick all 9 M5 nuts in all the sockets that need them.

2. Stuff an M5x20 into each of the screw adjust mounts' slots and wind it all the way up, then back it off until the one of the adjustable anchors can fit on top of it with no space in the joint. See the pictures if you're not clear on this.

3. Bolt the 3 fixed anchors with the wire slot DOWN to the Kossel's three uprights. Mount these as far down as they'll go. (NOTE: you could slide them up a little bit -- or a lot bit -- to gain back some of your build envelope, but the higher they are, the more strain they'll probably put on your plastic corner pieces. The goal is to have the twisting/tilting loads transferred as directly as possible into compression forces on the frame horizontals, and the further up the anchors sit, the more of a moment you're inflicting on the corners to transfer the force).

4. Mount the 3 adjustable anchors at the top of each frame upright with the wire slots UP, and place them about 15-20mm down from the bottom of the plastic frame corner. You'll need the extra travel above these for the final tensioning later. Don't tighten these on too much.

5. Mount the 3 screw adjust mounts at the top of each frame upright with the M5x20 bolts inserted into the holes in the bottom of the adjustable anchors and scoot them all the way up so their top sides butt against the anchors' bottoms (again, see the pictures...), then tighten them down. Make sure the M5x20's are snug against the adjustable anchors, but not actually pushing them up yet.

6. The fun part: string the wire! Well, first put one end of the wire in the eye join and fix it good with two of the wire clips (leave yourself a tail of at least 5-8 cm); then wind the wire twice around the machine through the wire slots in each anchor, alternating up and down, until you get back to the eye join.

7. Run the second end of the wire through the eye join, snug it up, and tighten on two wire clips just enough to hold the wire in place. Clip off the excess wire, again leaving yourself a tail of at least 5-8 cm.

Now it's the really fun part: applying the tension!

FIRST, give the top of your frame a rock and a twist to see how much it can flex, just so you have a point of reference when you rigid it up.

NOTE that this design uses a single loop of wire strung all the way around the machine so that you can avoid all the hassle of trying to get six different pieces of wire the exact same length and tension -- as long as you don't lock down the clamp washers until the very end, and make your tension adjustments in small increments to each joint in turn, you should get perfectly even tension all the way around. You can test for even tensioning as you go by simply plucking the wires -- if they all generate the same tone, you know you're good.

1. We kick off this process by getting as much slack out of the wire as possible by hand, without using the screw adjusters. Do this first by just going around the machine, snugging up each length of wire, and working the slack around to the side with the eye join, then tugging the slack through the eye join and wire clips to hold it in place. IMPORTANT: make sure you get the eye join someplace where you'll have enough room for both tails, but also where it won't risk interfering with the printer's arms. I chose to mount mine pretty close to the top of its side, since the arms can only bump the wires on the bottom halves. This is very much most convenient to get situated while you've still got slack.

2. Once you've got most of the slack out, you can go ahead and mount all the clamp washers with the M5x12s. DON'T tighten these on, just get them on enough to put a tiny bit of friction on the wire.

3. Okay, now you can GENTLY tighten ONE of the clamps for the side with the eye join. This will hold that corner in place so we can work out slack around the machine and back to the eye join to take it out.

4. Start working around the machine again, taking out slack (easiest way to do this is to pull the wires gently OUT or IN, one segment at a time, in order) from the fixed corner and back to the other side of the eye join, where you can work it out through the eye and wire clips.

5. Don't go crazy with the wire, just get it so it's not sloppy. Now is a good time to do an initial check of how your build envelope is going to change by checking where the arms will touch the wires around the outside of the volume, and to make sure that your bowden and wiring have freedom of movement throughout the printable area. I ended up routing both through the bottom/center quarter of the same side of the printer, but had to shift my extruder a bit to get the bowden moving freely. Be especially sure that the wire and bowden can't get caught with a loop on the wrong side of the wires in the case of a homing move starting close to that side of the build plate.

6. When you've got the slack pretty well out, tighten down all the wire clips really well on both sides of the eye join.

7. Now loosen that one clamp back up, along with the bolts holding on the adjustable anchors.

8. GENTLY screw in the M5x20's in the screw adjust mounts until they all have about the same tension on them.

9. Now start going around the machine, CAREFULLY tightening each M5x20 bolt by 1/4 to 1/2 turn each time. The tension will rise faster than you think. GENTLY rock/twist the top of the machine from time to time -- this will let you track how the rigidity is coming along, plus it will help distribute the tension evenly by helping the wires scoot around the corners if they need to.

10. When the frame feels decently solid and the wires feel decently and EVENLY taut (they should make a clear bass note when plucked, and all play about the same note), go ahead and re-tighten the M4's on the adjustable anchors to fix them firmly to the frame.

11. This is also a good time to go around and make sure all the other M4's are good and tight, and to re-tighten the bolts on the frame corner braces that you loosened earlier.

12. FINALLY! Go around the anchors in order and gently tighten each of the M5x12s to tighten up the clamps. This will put a final lick of tension on the assembly.

Okay, last steps:

1. You'll want something on the wires to prevent wear and tear in the event that printer parts do contact the wires. I used scissors at an angle to spiral-cut some plastic drinking straws, which made pretty good ad hoc fenders when wound onto the wires and taped together at the crossing. The bottom halves are crucial to shield against arm contact, along with anywhere your bowden, wiring, etc. might brush up against.

2. Test carefully at first! A gentle bump or slide of the arms against the wires won't hurt (the wires will give outward a bit even under a lot of tension), but a hard crash into them could seriously strain your frame. Likewise pay close attention to your bowden and wires until you're confident they're not going to bind anywhere. I assume no liability if you bork up your machine with this.

3. Re-level your printer after this mod (duh).

4. There's going to be a wear-in period where some tension is lost to the wires conforming better to the corner radii, the PLA deforming a bit, etc. After a few prints, start by re-tightening all the M4's holding the anchors to the frame, then loosen all six corner clamps again, along with the adjustable anchors' M4s, and go around in order again, tightening the M5x20's by a quarter turn at a time, until you're back where you want to be, then tighten the adjustable anchors' M4s again, followed by all the clamps. This might need to happen a few times.

5. Probably also get some loctite on the wire clips' nuts.