Printing project feet with TPU

Sorry if this is a sidetrack but I see two people with TPU experience so here goes: I plan to print rubbery feet for a project and am a bit overwhelmed with the TPU options. Do you have a recommendation for a good TPU or a vendor who carries generally good quality TPU?

I think I need something around Shore A70 or D12, something like a smartwatch band.

I have an Ender 3v2 that I upgraded to a direct drive specifically for printing TPU.

Michael will be a better source of info. I have only two prints under my belt.

I was just looking for a cheap option on Amazon for my ink stamps. I purchased the Overture filament. Not the cheapest but pretty close.

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I have printed with Ninjaflex and Overture. The Overture is, I think, a little harder. This is what I bought:

Reading the description: Shore 95A. Ninjaflex is Shore 85A. So I was right.

I currently print TPU (either kind) at 30 mm/s, but I’m using a volcano hotend and a 0.6mm nozzle with 0.45mm layers, driven from an orbiter with dual drive gears. For a standard v6 hotend, you might need to go slower; 15-20 mm/s. It might be possible to go a faster with a CHC hot end — there are 115W CHC hot ends that are compatible with volcano nozzles. I’ve been pondering switching to a CHC hot end in my printer with the 0.6mm nozzle and seeing how fast I can print that way. But the combination of 0.6mm and volcano makes TPU print in non-geological time.

I used both Ninjaflex and Overture to make furniture feet. They have successfully kept my couches from sliding across wooden floors. I would expect either to be OK for your purpose. I don’t think that the softness is actually a big part of its coefficient of static friction; I think that’s a characteristic of the polyurethane itself.

I make sure to keep it dry. I don’t know if it’s necessary, but I print it from my drybox as well as drying it out in my filament oven (a box made out of insulation with an old heated bed and an old 8-bit controller running it). Before I had filament drying capability, my Ninjaflex would spit and bubble a bit. (I’ve had the Overture only since last November, after I started drying filament reflexively.)

Here’s an example of print quality I’ve gotten:

That line on the corner is the seam; I haven’t tried to tune it to reduce the seam; I just don’t care enough.

This is a bumper on spiral stairs to protect heads from a square end of oak. It has low infill and rounded edges to be squishy.

I print TPU, like PETG, on a PEI bed with hairspray as a release agent. It can bond pretty tightly to clean PEI.

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Thank you for the info!

The printer I’ll use has one of the all-metal direct drive micro-swiss units with v6 nozzles, usually 0.6mm. It does have a magnetic PEI sheet so the hairspray is a good tip, thanks.

Unless I’ve just opened a filament roll I try to give it a couple of hours in the dryer. A dehydrator keeps the workshop pretty dry, too. When I print TPU I’ll probably feed it directly from the dryer.

I’ve ordered the Overture TPU so I’ll see soon enough how it goes.

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Curious how well this worked for you, since I saw you are getting close to shipping the Altos off… :smiling_face:

I went with an off the shelf solution instead of printing the feet so I haven’t printed any TPU, yet. I plan to mess about quite a bit in may, including some TPU tests.