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Aha, I see..

Big Bear transmission inspection after about 2 and half hours of Lipo 2S (4000mAh) heavy runs (intentionally ran it quite brutally for this as I needed to know about the resitance of my gears - about 4-5 packs passed).




The nylon diff is not showing any signs of wear. it was a mix of different printed parts, but I'm quite sure they would be resistant enough. So this is perfect now.

I have some thinking about the Super Wheelie and will get another idle gear with a small modification printed in SLM, and normally it should be fine... When ordering this I'll get the final diff gear printed set and a metal printed idle gear for the Hunter as well... The Big Bear was clearly the most challenging to tackle, and the nylon idle gear of the Super Wheelie and Hunter are still alive at this stage (but shows clear signs of wear on the Super Wheelie). SLM will come to the rescue...

That's awesome Marc. Congrats for this challenge.

My daughter loves to  run cars in vintage events, and she asked for a bit more cars than her Lunchbox and here TT01 to have more variety (the DT03 is nowhere a vintage car, so it's no go for vintage events). And she confesses recently that she likes the Super Wheelie. Luckily, someone proposed me one recently, we agreed on a price but it was delayed because I just got two recent entries that day... My friend sold his own Super Wheelie he played when young adult and he kept it as he had kids and he expected the kids of his kids to pick up rc... He decided to sell it while the targeted kids seems to have only interest for their playstation, and he wanted to find a new home with someone who wanted to run the car... There will be a bit of work, in particular for the windshield and its attachement, likely a bodyshell clean-up and some nice paint to follow...






My daughter is happy, but she told me she expects it to become more pink

It looks very nice.

Following the expérience with the Big Bear idle gear, I redesigned the diff cluster. I also made a different version of the idle gears designed with SLM metal prints in head.


I've set an order online for a final check. The Super Wheelie Idle gear is printed in 2 versions, so I should be able to assess the needs for the tolerance, and eventually review the idle gears accordinly for Hunter and Big Bear. I'll be clear on this by end of next week, I suppose.

Got a delivery today...

Diff sets and idle gear for the 3 targeted configuration. This should allow me to check the assumptions about SLM printing tolerances and validate what is needed for Super Wheelies. The Big Bear idle gear is the same dimension as the one working already so this is good. And I'll should be able to assess the Hunter/Galaxy one as well...


I also got a gearbox printed for teh Super Wheelie.  I wanted to print one and check my dims for the ball bearings addition before to add this into shapeways...


Later on within the week : test duties

SLM idle gears prints are kinda "predictable"
- Big Bear idle gear is spot on, as long as you get the tolerance for the shaft right (+.3mm)
- Hunter/Galaxy is spot on, as long as you get the tolerance right for the shaft and the ball bearings casing (+.3mm)
- Super Wheelie : the big part of the idle gear needed an offset of -.1mm everywhere on the external profile of the bigger gear. Rest of the design is fine (The print with initial design is again 19.4mm for 19.2m diameter expected, while the one with -.1m offset of the external profile is 19.2mm and working smoothly).

So this is it... Diff set remains to test in the different configurations, but at least I have now idle gears for those cars working and reliable...

Perfect Marc 

Focus on the Super Wheelie. I put the new diff in. It required a minor shim addition between the locks and big bevel gear on each side but it is now perfect (nb: the previous big bevel gear got printed with some supports, and the left overs were what was maing the diff working ).


I'll have to check out the same for Hunter/Galaxy and for Big Bear before doing the modification on the design (it will be very easy to do). In the meantime, the Super Wheelie works, there is no cracking sound anymore and I don't care opening full throttle... But the motor is probably quite worn, and I'll need to replace it at some point...