Print Head Cable catching on Bed

Hi all and thanks for my admission to these forums. I am exploring the realm of 3D printing starting with a little M3D and now upgrading to my Lultzbot Mini. I was hoping to get some help with an issue which is this:

When my Lulzbot Mini calibrates before a print, the cable hangs on the back of the bed causing it to not reach the back sensors. The print head crashes right into the bed and ten calibrates to that level, throwing off the print. In fact, it starts printing about a 1/4 inch off the bed and therefore, not at all. I have to hold the cable while the print head aligns with the sensors and even after the print starts, the cable still catches on the bed frequently, although not in any way that interfere’s with the print. Is this common or is something wrong with my machine. This issue doesn’t appear in any reviews I read before choosing the Mini so I feel something may be wrong with my machine. I’m wondering if I secure a plastic bar across the back frame under the cable, it will stop it from catching on the bed.

Any advice?

LG Johnson

Please post a video so we get a better idea of what is going on. A video is worth 1000 words!

Jim

I’m having the same issue with my newly delivered mini. Please see the pictures and video. Any advice on how to address this?

Thanks,
Topher
LulzBotMiniPrintHeadCatchingWasher.mov (3.85 MB)

The cable chain should not be able to flex down that far. Please check the chassis anchor point and see if the mount is either loose, damaged, or popped out of the socket. also see if the little shelf that prevents the cable chain from going down that far is intact,

Also it may be a good idea to count the number of chain links and compare that against the ohai kit installation pictures https://ohai.lulzbot.com/project/mini-104-z-axis-left-assembly/mini-v104/ to make sure there isn’t an extra link in there for some reason.

I got a quick reply from Lulzbot support. :smiley:

They sent me a motor frame mount that appears to give the tank track more support. Replacing will be a challenge, but Hey welcome to the world of DIY. I recommend for in a support ticket with them to get an official reply, as the STL file they sent me was described as “experimental.” Out of respect to the support team and to make sure Lulzbot can track issues appropriately I encourage you to contact Lulzbot support yourselves.

Shout out to the support team at lulzbot. I’m a first time 3d printer owner, and this could have been a more frustrating moment.

I have a quick work round for lift the tank track. Using a pair of paper clips and a rubber band. It’s very hacky fix and I’m not proud of it, but it’s working until I get the piece printed and in place. I’ll get a picture of it up on the forums later.

Thanks
Topher

Had the same problem with a mini out of the box there was a post about a printed block that fix mine but now i can’t find it now try looking for that post.

Hi,

Here’s a picture of my work around. I used two paper clips. I bent them cross the length of the paper clip to form hooks, and attached a rubber band to each. One hooks to the tank track, and the other to the plastic tie. The rubber band does not interfere with the print head movement. You can adjust the tension depending the # tracks pieces you attach the hook to.

It works rather well. It ain’t pretty, but it reliably works. I can hit print, and walk away.

Cheers,
Topher