Turnigy Trooper "Diff Case"
thingiverse
This is a differential basket for front and rear diffs for Turnigy Trooper. Such part doesn't exist for the original Trooper. It's available for Turnigy Trooper Pro (https://hobbyking.com/en_us/34573-diff-case.html) however I'm not sure it fits the "old" one. With such basket you can do a locked diff pretty easy - all you need is a 5mm drill and put 2mm pin through it ;) I added some epoxy glue around the pin to make it stronger. Sketchup file is attached, so you may edit the part to fit the bevel gears (https://hobbyking.com/en_us/diff-bevel-gear-s-w-shaft-1pc-bag-a2016t-and-a3002.html) and have (stock) open diff.
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