Show your MODS

[clough42]

I also see a new connection method for the Z Rods to the stepper motors. Is that a standard part for the i3v or a mod? I find that my rubber connections are prone to slipping. They do provide some protection in a head crash as they will release and push off, but as even the lightest lubrication eventually makes its way to the bottom, it discolors in the vinyl tubes, so I know it's there. They aren't as tight as they used to be.

I replaced the vinyl tubing with aluminum Z couplers for the reasons you mentioned. Oil was getting down into the tubes and I figured it would eventually cause a problem. Also, the tubes don't really center the threaded rod up very well, so the Z rods wobble when printing.

The coupler is designed to allow the shaft to flex as it rotates, but it also essentially suspends the weight of the X assembly on an aluminum spring, and it rings as the Z axis turns. They're really designed to be used with ball screws that have thrust bearings in the mounts. I went ahead and slid the threaded rods all the way down so they actually contact the motor shaft, and this stopped the ringing noises.

I'm not worried about a crash, because the nuts will ultimately pop out of the traps, limiting the downward force that can be applied.

[RobH2]

I replaced the vinyl tubing with aluminum Z couplers

Did you make or buy the couplers?

[clough42]

Did you make or buy the couplers?

Bought them on eBay. Just search for "5x5 flexible shaft coupler". There are lots of Chinese sources that ship worldwide and there are lots of local vendors marking them up, but with faster shipping.