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For the maiden voyage, shakedown run I opted for my old Pro-Line Waffles glued to my old Traxxas Cat wheels. The steering with the Tamiya linkage leaves something to be desired, but I still managed a cartoon like endless barrel roll from a fishtail turn. Oops. I guess I'll see if i can separate the tires from the rims and print up a new rear arm.
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Oops , what are they made of ?

They are Taulman 910 nylon.

I stink at taking videos (kid is "too busy" to help) but I am awesome at destruction. I fixed the steering so it's decent but might need to think about a wheelie bar for when the rear tires do hook up, although the Tamiya 10.5T isn't quite what I expected.
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Frankentruck wrote: ↑Sat Jan 14, 2023 12:10 pm although the Tamiya 10.5T isn't quite what I expected.

I believe that the esc is the holdup. I've often read that they underperform, regardless of the motor used.

I thought it would be kinda cool to have Tamiya electronics but maybe I'll try a Novak from my stash.

What temp are you printing the nylon at ? Could be a little cool and not layer bonding enough , that or try some CF Nylon as the layer bonding is so much better .

This specific nylon is relatively new to me. On thinner parts it has had good interlayer bonding with some flexibility. The right arm has a nice top to bottom crack, so across the layers unlike the last 2 left arm failures. I did just get some hardened nozzles so I might try some filled materials. Overall this is a pretty rigid nylon that gives good finish with minimal stringing. Maybe I'll play with extruder temperature too. Although the tumbles and crashes that have resulted in carnage aren't too surprising.

Ha ha , enthusiastic testing of the design , not crashes
The other thing to try is orientation on the bed , it's nice to have weak spots like the hole for the suspension pivot rod and the wheel bearing facing the bed , but if your shearing across the layers not between them it's not going to help.

There is one thing about printing Nylon that most people miss , to print it we have to dry it or it prints like crap but Nylon needs a water content otherwise it's brittle , most printed nylon gets stronger over a few weeks as it absorbs moisture from the atmosphere, it may help to stick the nylon parts in a bucket of water over night before using them .

I've considered changing the print orientation but the geometry of the arms ends up changing weak spot locations. I'm looking into turning the arms into subassemblies for a few reasons, which includes ease of replacement. I hadn't considered the soaking though.

I think another part of the issue is the shock stiffness. With the shocks so far back on the arms they have more leverage than a typical off road arm setup. It probably takes too much force to compress the shocks. I need softer springs, might even need to wind my own.

Liking this!
As you can see from my grasshopper post, I'm all for trans swaps in this chassis!

Get rid of the awful front end too, even of its just with crp double wishbone parts.

Awesomely, changing to a Novak SS ESC yielded more power output from the motor.

Not so awesomely, the high off-road stance CG and soft front springs resulted in a nose tuck barrel roll that destroyed another suspension arm. The failure was a feathered split across multiple layers so I think the demands of the geometry and 'my driving' are justifying going with The Armageddon Design option. I may also revise the front suspension. It definitely is getting overwhelmed.

I switched to a Novak Havoc ESC because it has Lipo support built in, but it doesn't like the Tamiya brushless motor and throws a fault code for motor not having temperature monitoring. So in goes a Novak 13.5 with it.

Rear suspension is now significantly beefed up with some goodies from Factory Works. It's sort of an Oreo / Double Stuff Oreo arrangement. Next I'll need to work on the front end. The steering is not acceptable.
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That's a really cool project. Turned out nice. Even the stance looks right. I won my very first race with one back in 1986.