Parametric Heavy-Duty Tube Roller Squeezer Wringer Thing

Most "tube squeezer" designs are based on forcing the tube through a fixed slot. This is either achieved by manually cramming the tube through a slotted novelty-shaped plastic toy or by using a flimsy rotating key in a feeble attempt to pull the tube through another flimsy plastic part. These designs cannot compensate for differences in tube thickness or the presence of folds or buckles such as can be expected with heavy aluminum tubes that have been crumpled. Most are intended to be left on the tube, which is inconveniently bulky, wasteful, and typically unnecessary. They're almost universally cumbersome to use and often ineffective at the task. If it's less effective and convenient than striking the tube across the edge of the countertop, then I see no point in using these sorts of things.

Of the few roller-style tube wringers I've found on Thingiverse, none appear to be practically printable without modification. None appear robust enough for practical use, and of course none are configurable. So I guess I'll make one.

The goal is to make something that works adequately even with heavy aluminum tubes and viscous products. A hinged wringer design can adjust to various tube thicknesses and can accommodate tubes with folded closures and wrinkles/folds which would otherwise not fit through a fixed-slot contraption. The corrugated rolls help with traction and they periodically crimp the tube tail, making it easier to neatly fold or roll the tail afterwards -- a convenience for heavy aluminum tubes. The end gears allow the rolls to stay synchronized over a wider range of spacing. This helps prevent slipping under load. The redundant gears compensate for some degree of frame twist.

Compared to the metal tube wringer I have, the roller design is a lot less prone to slipping and the handles are more comfortable. It's also configurable and available. On the downside, it's still made out of plastic, so it's still a bit bendy. I've made at least some effort to make it robust. While I haven't broken one yet, I'm not going to say it can't be done.

Read the SCAD file for information about printing and assembly. Tweak clearances if necessary for your printer.

UPDATE: I had a few of these fail due to the roll splitting at the ends where the knob fits. In part, this was due to the material I had used. JAYO PLA-meta is apparently extremely consistent at failing due to moisture-induced stress cracking. Many of the functional parts I've printed with it have failed due to cracking under minimal loads. The other part of the problem is way the hexagonal plug interface produces hoop stresses when transmitting torque.

I changed the interface to use a spline instead of a demonstrably not-the-bestagon. I printed wrench-compatible test parts in PLA using both interfaces (see photo), and observed their failure torque and mode of failure. The original hexagon interface was springy, and began to cam out around 10 in-lb, ultimately slipping around 15-20 either by permanently stretching or splitting the roll. The splined parts were stiff up to about 20 in-lb, and failed around 25-30 in-lb by sudden torsional shear failure of the driven bushing at its thinnest section. The splined roll did not exhibit any noticeable permanent deformation of its socket. I consider this to be a significant improvement. As far as I'm concerned, there's no need to keep the old model up.

The dimensions should be compatible with the old model, so if you want to upgrade, the minimum you need is one new roll, bushing, and knob.