My First E-Dune Runner

[mulepic]

You're right. I'm still considering options. Chances are I'll need to buy some 10mm stock from mcmastercarr b/c the shaft in the motor is most likely hardened. Also if I use a longer shaft I can support the motor on two ends w/ bearings.

 

[mulepic]

I might have come up w/ a much easier approach. Instead of trying to use the existing clutch plate (anyone know what that thing really is called?) I'll make my own aluminum piece to hold the clutch shoes. I'll mill a square hole in the aluminum piece. Then the 10mm rod will get flats milled on it to fit in the hole. Much easier than dealing w/ existing parts.

But still thinking about it. I might get even easier.

 

[Guest]

Instead of trying to use the existing clutch plate (anyone know what that thing really is called?)

It is the gear plate. Redcat calls it a gear mount.

 

[Guest]

I'll make my own aluminum piece to hold the clutch shoes. I'll mill a square hole in the aluminum piece. Then the 10mm rod will get flats milled on it to fit in the hole. Much easier than dealing w/ existing parts

If you go that route, just ditch the clutch. That's extra weight you don't need.

 

[mulepic]

Maybe I'm missing understanding the comment, but we need the clutch to avoid killing the ESC w/ the startup current. It's how those go-carts and e-bikes are able to use these motors/escs.

 

[Guest]

None of the electric 5th scales use a clutch.

 

[mulepic]

I can't say I feel confident the current approach taken for e-5th is a good one. That's why I'm exploring the route of e-bike and carts i.e. high voltage, low current, cooler components, and longer run times.

The e-5ths still have many issues w/ their ESCs being smoked b/c they are running high current setups and that creates too much heat. The ESC's just are not built to handle the sudden current spikes needed to get these things going/stopped on the track.

 

[Guest]

I hear ya. It's cool to see a different approach. We all know the manufactures have the "build it for less" to contend with.

 

[Deluge]

Tekno has an Elektri-Clutch. Designed for 8th scale electric conversions, but here it is in action. Maybe you can get some inspiration from it.

[ame]

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[Guest]

That's cool!

 

[mulepic]

Yep, that's exactly the idea. It's amazing how much smaller the 1/8 clutch is than the 1/5 one.

On the list of things to do is:

1. find where to get 10mm round stock. I'd actually prefer tube but that's not working out too well.

2. find a 10mm id bearing and carrier to support the back of the motor

3. get a good price on a 120A HV esc

4. build a nice connection point for many 2s batteries to be able to run 6, 8, 10, 12, and 14s.

And the list will grow from there once things start to show up.

 

[Deluge]

Challenges, challenges.

 

[mulepic]

That's for sure but I enjoy this part of the hobby as much as driving them. Last night I started to worry about the outrunner surviving the off road environment. How well will it handle the shock of jumps and crashes? How am I going to keep dirt out of it? I did start looking at inrunners then i.e. the leopard 5698 460kv. But I'm still considering the outrunner.

 

[mulepic]

I have completely talked myself out of the outrunner approach. Trying to prevent the dirt and shock from destroying the motor was proving to be too difficult. I considered outrunners b/c they are the only motors w/ low enough kv for the higher gearing of the dune runner. But since I found the leopard 5698 460kv it became apparent how much easier it would be to mount it up and be reliable. So I ordered one from helipal.com. I just hope I can get my $40 from leadershobby.com. There's no info on the site how to cancel orders.

The 5698 is also slightly narrower and should not have any issues w/ contacting the rear driveshaft. I'll still run this on 10s w/ a clutch to keep the current low and runtimes longer.

 

[Guest]

Cool...

That does sound like a better approach.

 

[mulepic]

The 120A HV ESC and lbp5698 460kv motor are on their way. I'm drawing up the clutch mounting block. I'll make the part out of delrin first just to get a better idea how it'll fit/work. Once I'm happy w/ the design, I'll make it out of aluminum.

 

[Deluge]

I had a cheap brushless motor die because of dirt. Pebbles got jammed between the armature and the magnets. Completely tore it up!

 

[mulepic]

The inrunner is just going to be much easier to implement. There is much less to worry about w/ all the dirt flying around and mounting it should be straight forward.

I just saw that the motor was shipped out DHL yesterday. So maybe by the end of the week I'll have it.

 

[mulepic]

I machined up the pieces that mount the clutch shoes to the leopard 5698.

clutch mounting bracket:



The silver shaft represents the motor shaft but it doesn't have a flat on it like 5698 will. The brown piece (the black one won't show up in the photo) is just something I put on there to show how the bracket will clamp to the motor shaft.



What it looks like w/ the clutch shoes mounted on it (less the spring)



The delrin is just something I use to rapid prototype. These pieces will be made out of aluminum just like the stock clutch mouting plate. When the motor shows up I'll work on the motor mount.

 

[Guest]

Very nice.

You've got some skills man.