I've been working on this for the last couple of days. This is the easier to print, and slightly refined version of my one piece design. Dimensionally, this is the same size as the one piece; same width, mounting position, and radius. There are some differences in the design to give it some more character.
Further, it is broken into 2 parts; a centre, and a grip. You need 1 centre, and 2 grips, along with 8 M3x6mm screws to assemble it. Print the centre piece in PETG or ABS; PLA has a strong tendency to split on the layers when inserting the throttle axis arms. After printing, use a small standard screw driver to scrape the bridged portion of the socket that the throttle arms mount in. The fit should be snug, not press fit. I spent a lot of time and prints making sure it was snug, not loose. This requires some minor work to finish the sockets, which is scraping gently on the bridged side. The grips can be printed in PETG, ABS, PLA, TPU. I'd suggest PLA or TPU. A firm TPU gives a nice grip. Print everything with 20% ~ 30% infill. Orient parts flat on the print surface; it will be pretty obvious how to orient them.
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