3D Printed Trekking Poles! #Tinkerfun

myminifactory

Human: Can you actually 3D print trekking poles?! Some of the best ideas come from turning ridiculous concepts into reality. And yes, it's entirely possible to create trekking poles using just a few dollars' worth of aluminum tubing and some rubber chair feet... plus a 3D printer! Read on for the reasoning behind the design and its features, or skip ahead to the printing and assembly instructions... A FEW DESIGN GOALS: * Adjustable length. This is the part that makes things complicated. The pole needs to support the weight of a person down the long axis without being compressed to a shorter length, but while still being easy to adjust. * Robust feet. It should be possible to fit standard rubber feet onto the poles, and have force distributed evenly across the feet. * Ergonomic handles. The handles should look like handles, and not just tubes. * Strong straps. The handle straps, which take the majority of force, need to be anchored firmly. IN-DEPTH DESIGN From a purely printing perspective, it's clear that all parts are designed for easy printing without supports. But let's get into the functional aspects of the design, and the problems they're intended to solve! Adjustment mechanism. Let's start with this, because it's the most important element of the entire design! Conceptually, this works by using a screw attached to the outer to push wedges down against the inner pole, and thus hold it in place with friction. It took several different designs to refine the design to be tough enough, provide enough friction, and still be easily printable (and tolerant of print variances). You'll notice that the two wedges are attached to a kind of half-ring. This gives the screw knob more surface area to push against. However, the two are separate so that they can move inwards (and towards each other) against the inner pole, without the ring working against that, and without having to rely on assumptions about the amount of flexibility in the materials used. Early prototypes used three wedges rather than two. However, using two wedges makes it easier to adjust the poles, so they're a better choice for this design. Gathering Materials * Aluminum tubing (for the poles) * Rubber chair feet * 3D printer filament (for the adjustment mechanism and handle) * Webbing or straps (for the handle) ASSEMBLY Most of this will be obvious! The only thing that could really cause a problem would be putting the feet onto the lower poles before running it through the upper pole from the top, as the foot is intentionally too large to fit, to prevent it getting lost inside when collapsing the poles for transport. Anyway, follow these steps, and everything should work out: 1. Cut the poles to length, as discussed above. If in doubt, 70cm for each length is probably reasonable for most average heights. Take care to smooth off the cut surfaces, or else the printed bits won't fit! 2. Fit the main adjustment bracket to the bottom of the outer (upper) poles. Glue them in place and let the glue dry. 3. Fit the inner guides to the inner (lower poles). Glue those in place, too, and let that dry. 4. Put the straps through the hole in the handle, and then put the handle onto the top of the outer pole. Make sure the strap goes around the pole, inside the handle, so that it's anchored around the metal, not just wedged into the plastic. That way, the strap strength depends solely on the strap itself, and not on anything plastic. Glue the handle into place so that the pole is just below the top of the handle - remember, we'll be screwing down the cap over the top, so don't let the pole stick out and obstruct that. 5. Drop the inner pole into the outer pole via the handle end so that the inner guide is at the top. The guide stops the loose end of the inner pole rattling inside the outer pole. The bare end of the inner pole will protrude from the bracket we glued to the bottom of the outer pole. Pull it through a little way! 6. Take the adjustment wedges, and slot them into the adjustment bracket. Then, take the adjustment knob and screw it into place. The middle section is now complete. 7. Screw the caps onto the handle tops - we're finished with the handle end, now too, which just leaves the feet. 8. Push the foot adaptors onto the bottoms of the inner poles. If you like, glue them on, though if it's a tight fit they should be fine. Push the rubber feet over the top of the adaptors, and we're done! Now you're good to go! Happy trails! This object was made in Tinkercad. https://www.tinkercad.com/things/7b8j5J1bBPg Uploaded to the #Tinkerfun contest, too!