3D Printed Stainless Steel Outdrives

[RS Chris]

stainless in general sucks to machine depending on the geometry, so i can see tapping being a b!tch. I believe from shapeways it says they use 420 stainless powder, it may be somewhat hard depending on how it was created. Then then take that stainless and somehow infuse it with bronze. bronze can be tricky to machine also.

I used to do CNC waterjet cutting and I can tell you stainless was by far the hardest material we ever cut. And occasionally we had to tap certain parts. Long days running the machines and many broken taps on 316 and 308 stainless.

[Phin]

The accuracy isn't there for a gear, not even close.

For the gear diff, I've been playing with the idea of making an RC10 Stealth case that takes an SC10 gear diff. I don't know how much demand there is though...

Using the SC10 diff gear would run into one of the problems the MIP Changebox transmission had...the larger 52T gear raises the outdrives and the drive shafts become too short. If you went that route you might also need to make taller axle hubs like the RPM GT or Losi JRX Pro to compensate.

[mk-Zero]

Good to know. We could use longer CVA's too though. The Worlds ones are too short already even with a Stealth diff.

[tamiyadan]

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[mk-Zero]

Shapeways says +/- 5% + 1 layer, so as far out as some of the features are, they are within their stated tolerance. I will probably adjust the models some though, and then ideally just clean them up on the mill and lathe.

Tonight I got them all sorted out except the drive pin slots. Those were my mistake, I accidentally made the slots .080" wide, should have been .104", but then they printed undersized on top of that, at like .070". I had to order an end mill bit to slot them, it's arriving tomorrow. And last night I made a fixture to hold them in my mill vise.

Everything except the slots fixed

By this weekend I will have the slots fixed and have them in my RC10M, and then I'll abuse them on the street and see how they hold up. Then we'll go from there.

[jwscab]

Those will also look pretty cool polished up

[NomadRacer]

I'd be up for polishing a set

[mk-Zero]

If these work okay on my car, maybe I'll get a couple sets out there to some willing beta testers

[lmw94002]

If they work, i'd be up for a set or two... cause I have a pair of transmissions to rebuild with absolutely shredded outdrives.

[mk-Zero]

So tonight I machined out the grooves. The bones fit in them really nice now and spin and articulate smoothly.

Then I went a head and assembled the diff. Went together nicely. The feel is a little inconsistent, I think I am going to need to flatten out the raised areas that the drive rings sit on. That will be easy once I have my lathe.

In the mean time, I'll put this diff in the car and start abusing them, see what they do.

[lmw94002]

Looks good!

[jcwrks]

A complete stealth diff is available on eBay if anyone needs the outdrives.

http://www.ebay.com/itm/Vintage-Team-Associated-Rc10-ball-diff-/232470174458

[mk-Zero]

And he's got 2 of them!

Tonight I plan to swap the diff I built with the printed outdrives into my RC10M and then take it to the track tomorrow to abuse. I'll report back my findings.

On another note, I am now the proud owner of a 7x12 lathe, so if the printed outdrives end up working I'll be able to machine them to spec pretty easily and supply them to you guys. I may also buy a set of b4 outdrives and turn them down, just to try it.

[jwscab]

BTW, here is a crappy pic I posted a while back when there was a shortage before the re-re of the B4 parts machined.

[aip47-2008]

Good to know. We could use longer CVA's too though. The Worlds ones are too short already even with a Stealth diff.

Or lower the diff., similar to the B2 or like losi did with a recess in the chassis.