Yup Miles&Jules! Probably just a sportsman but we'll see how it goes! I'm already in possession of a number of kmart 12v drills, hopefully enough to get me through a competition! Certainly planning to make a version 2.0 with better parts after the first attempt

Thanks for the offer Marto, I'll see what I can do locally, but if I have any major problems making the parts I'll definitely reach out to you. Plan is to fabricate the frame first then I'll look at the tricky bits (drum endcaps and mounting).

Maybe run it at 3s for 12v drills….they will be slower but they wont explode. Also if you can work out a way of having outer wheel supports that will save them to. We made a steel hub that came off the threaded drill through the wheel and into an outer bearing. This was all held in 20mm breadboard motor mounts. That really stops em from exploding to.
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Miles Blow - Julie Pitts
www.mulesfilm.com.au
www.wombokforest.com.au

-Pickasso- Vivid Sportsman champion 2015

Hey guys I think I made a mistake.

I keep trying to use a drill as my weapon motor but for some reason it transformed into a 2000W Brushless system? Has anyone else experienced this error?



Forgot I had it lying around. It's 200Kv, Might surround it in rubber and use the outrunner shell itself as the friction drive. Need to see whether that'll give me enough drum speed as I'm not sure what the standard is... 1000RPM? 5000RPM?

Thnk that will be to fast for a sportsman though…be interesting if it works as a friction drive though
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Miles Blow - Julie Pitts
www.mulesfilm.com.au
www.wombokforest.com.au

-Pickasso- Vivid Sportsman champion 2015

200KV, on 3S that will do only 2200rpm. On 6S it doubles.(and is the limit of that TZ85)

Drum speeds are now up to 14Krpm

Thanks, There's also about a 1:1.25 ratio in the friction drive that slows down the drum further. Implementing a gearbox would be quite a complication. I think I will go with this for now and switch out for a higher kV outrunner after Proof of Concept. Normally I have too many RPM so it's nice to have too few for once!



I just need to make a 63mm bore 80mm OD tyre for it, seems pretty straightforward.

Friction drive should work. Just make sure you can adjust it as the tire wears.

Any real pics yet?
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Steven Martin
Twisted Constructions
http://www.botbitz.com

Made some actual progress today, I had to learn to weld as well so things took a while. I cut the angle and welded it up into a box, didn't get a good picture post weld so here's pre-weld. 6mm Aluminium will bolt onto that 3mm steel so it should be strong!



Hoping that tomorrow I can cut the aluminium, bolt it all together and do the wheel cut-outs. Tonight I will be 3D printing my drill mounts, though does anyone sell mounts that are a bit stronger? I'm concerned that they will be a weak point.

Greatwork ..did ya see my aluminium box section reinforced drill mounts in the tech section? i can send you the stl if ya want
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Miles Blow - Julie Pitts
www.mulesfilm.com.au
www.wombokforest.com.au

-Pickasso- Vivid Sportsman champion 2015

Wow that's a great design. I'd love the stl, do you have it somewhere for download? or you could email it to thomas.mcmenamin@yahoo.com. Thanks a bunch. The version that retains the original drill gearbox is enough for me

No worries... let us know how they go…also remember to print the mounts laying flat so they are stronger…also acetone coating will add strength.
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Miles Blow - Julie Pitts
www.mulesfilm.com.au
www.wombokforest.com.au

-Pickasso- Vivid Sportsman champion 2015

Here's where I am now, printing the new mounts tomorrow (my printer is loud!), Then up to sydney for a few days so won't be able to work on it. Things are coming together, ordered some 30A botbitz esc's, I figure that's enough for 12v drills at 3s.

Which class are you building for, open or sportsman?
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So even the rain that falls isn't actually going to fill our dams and our river systems

I'm hoping open, I think the frame and armour will be strong enough, Just a matter of getting the friction drive right.

Had enough time to print off one mount before I had to drive up to Sydney:





There is a bit of space around the motor for the rear mount so it's loose... Strangely this was the same for both my old-fashioned drill mounts and Miles&Jules design. Anyone know why this could be? The piece printed with the correct dimensions, so it's not a printing error. I might just have to CAD the rear mount again with a bit of a smaller hole.