Printing process documentation

[Zufallsgenerat0r]

Could you provide some information on material's and settings used for printing?
Great project, thank you for the work.

[Tropaion]

I also would like to know that. My spring is way to flexible, my knob is wobling even if not touched.

[spoter368]

Used default 0.2mm layer, speed profile for the Prusa mini PLA. Turn off Arachne perimeter generation.

[hotsgit]

This flexure modded by lpurdy01 is apparently easier to print: #5

I used PLA+ (sometimes called PLA Pro or PLA Tough) with 0.4 or 0.6mm nozzle, 0.2mm layer. The higher print temperature than PLA mean it's less likely to creep/sag at room temperature. Creep can happen to PLA under continuous force (but nobody has mentioned yet that it's an issue for this mouse).

I think PLA+ is less rigid than PLA but the flexure is plenty stiff for me, and I can't see the mouse wobble when I shake my table.

PETG is too flexible/inaccurate unless someone changes the model.

[Tropaion]

I tried different materials and finally printed it with PLA-CF, got the overall best results with it.

[hotsgit]

I know that's good for stiffness, but have you had any creep (sagging over time just from the weight of the knob) or cracking with PLA-CF? I'd kinda expect it. Now I've found even PLA+ creeps noticeable in the sensor readings for me when I leave the mouse sitting plugged in for an hour.

So I'll either design a flexure to be made out of PETG or use nitrile O-rings configured like below. Regular elastics aren't as good for longevity.

[hotsgit]

Update, nitrile O-rings won't work; even when just stretched to 132% of original diameter for 5 days I noticed permanent deformation where they wouldn't return to the original unstretched diameter (~3% increase, but hard to accurately measure o-ring diameters).

Was curious whether time affected it, so I hooked an o-ring to a spring to test creep under nearly constant force:

After some better googling, apparently most (or all) elastomers have creep, though silicone MIGHT be tolerably minimal. Silicone elastics can be bought for cheap but not worth trying yet. The chart below is at the boiling temp of water and x-axis is log scale, but still shows creep doesn't level off.

PETG can also have creep, but I can't be certain that creep will happen on a thicker PETG flexure (it probably will).

I could try 3 steel springs, who knows, maybe they can be in a config without detrimental interference. But I can't verify that until I figure out why my OS3M mouse's signals are already a little spastic.