Multi coloured 20mm wide watch strap using single extruder

thingiverse

I designed and made this multi coloured watch strap 11 months ago as the original strap for my Amazfit Bip had broken. I've worn it continuously for 10 months, through a cold winter and in the heat of the middle east. It has lasted very well and still function fully although a bit dirty. The only reason I don't wear it at the moment is that the watch face has come away from the watch and I need to glue it back on, nothing to do with the strap. You can use any colours you like, I had these to hand at the time and it matched the watch. The strap is made up of several parts: the strap, the clasp, coloured decorative inserts and the fastening button. You can make and use the strap without the coloured inserts or you can change the look of your strap by simply changing the coloured decorative inserts for ones you printed in another colour. Update 26 July 2023: The watch securing pin holes are for 1.5mm diameter pins. I have now uploaded an 22mm wide version https://www.thingiverse.com/thing:6141963 When printing the small parts I found it helps to make sure I have a clean bed, cleaning it with window cleaner does the trick for me. I tried it when I didn't have any acetone and found it gave better bed adhesion post cleaning. Printing instructions: I found that I was able to print all of the parts without any supports. - Strap and clasp - use TPU in the colour of your choice. I used 0.2mm layer resolution, 3 perimeters (1.2mm) and 4 solid layers top and bottom (0.8mm). This gives 100% infill. The outer side of the stap is on the bed of the printer as it gives a better finish. - The fastening button - use PETG at 0.1mm layer resolution, 100% infill (need to set this), 3 perimeters (1.2mm) and 4 solid layers top and bottom (0.8mm). I tried this part in PLA but it was quite week and came apart so I changed it to PETG and it has been fine with no issues. At the time of making I printed a spare one in case I broke/damaged the original but I have not needed to use it as the original has been fine. - The coloured decorative inserts - use PLA at 0.1mm layer resolution (I found this gave the item a stronger layer adhesion on the overhangs), 3 perimeters (1.2mm) and 4 solid layers top and bottom (0.8mm). This gives 100% infill. I tried printing these parts in PETG but had problems getting the detail when printing several on the bed at once so stuck with PLA and have had no problems. I used the slicing software to add multiple units and printed about ten at a time on the bed. Creality slicer use edit, multiply selected models. PrusaSlicer use cut and past. I'm sure it's possible in other slicing software too. I would recommend printing a few extra as you may damage the edge on a few when inserting them. Assembly: - The fastening button - Push the narrow end of the fastening button through the solitary end hole of the clasp from the inner side to the outer. It needs to be pushed through to the second groove so that the larger flat disc of the fastening button is flush with the inner side of the clasp. When pushed together correctly the outer part of the fastening button will be flush with the strap. - Inserting the watch securing pins - If your pins have no side spoke then just slide them through the pin slot on the strap and clasp from either side. If, like mine, you have a side spoke then I found it best to insert the long smooth end of the pin into the side spoke slot on the strap and clasp, then push it all the way until the side spoke is up against the end of the slot. The short end should now go in the slot and the pin can be slide back so an equal amount of pin is protruding from both sides of the strap. - Finding the correct hole for the fastening button - Put the watch with connected strap and clasp around your wrist ensuring the strap goes over the fastening button and in through the strap slot on the clasp. Adjust to a snug fit and push the fastening button through the nearest hole on the centre line. A finger on the inside of the strap and a thumb pushing on a slight side angle from the outer may help the first few times. I found it got easier after a few attempts. Once the strap has been worn for a while it takes the shape of your wrist and the process becomes a lot easier. Make a note of this hole as you don't want to put any decorative inserts into it. - The decorative inserts - Simply push them at a slight angle into the remaining holes (not the hole for the fastening button) so that the groove engages on one side of the hole then press gently down so the other side does the same. If inserted correctly they sit flush with the strap. I ensured the bed side of the printed inserts was outer most so the final finish was uniform on the outer side of the strap. I hope you find this design useful. If so please consider tipping me. Thank you.