[SimonRafferty]

Hey Tom, great project!
Nice to see someone doing the Mech Eng properly!
I never considered printing a Hyper9! Obvious when you think about it. I guess I just figured, so long as you can measure accurately - if it works on CAD, it will work in real life.

I do wonder if you'll get the low end torque you need, mounting direct to the transfer box. Long ago, I converted a Freelander using a Suzuki SJ413 Transfer box and a Siemens motor which had roughly the same peak torque as the Hyper9. The final drive ratio is similar - but I found it struggled with steep hills and so ended up driving it in Low Range most of the time.

If it does prove an issue, I've seen that you can buy 'torque boxes' - an in line planetary gearbox, intended for applications like this.

My first car was a 1959 SII - which I still miss, despite having had a succession of Land Rovers ever since.
Best of luck with the project - I'll be watching to see how it goes (literally).

Si

 

[SimonRafferty]

You've done an amazing job since I last dropped in to this thread!

If the ratio turns out to be a bit too high, you could source a 109 T Ton transfer box, which is 1.53:1 in high range (3.27:1 Low). I think yours will be 1.15:1 High, 2.89:1 Low? That at least will fit straight on to your adaptor.

with 4.7:1 diffs - that would give 7.2:1 overall reduction compared to your 4.07:1.
That would result in 3120rpm @ 40mph (close to the peak efficiency of the motor)
5400rpm @ 70mph
8000rpm @ 103mph

Just a thought for the future!

 

[SimonRafferty]

I'd have thought it would be the same power requirement but maybe the higher RPM would be in a better efficiency range for the motor?

Highest efficiency is around 3200rpm for the Hyper 9

 

[SimonRafferty]

Good idea, however i'm using the LT230 transfer box

Doh!

However, Ashcroft make a 1.667 gearset for LT230's - only £240

https://ashcroft-transmissions.co.uk/product/1-667-gear-set/

That alone might be enough.

I also have a (home made) CNC Plasma

One of the single most useful tools I own. I love being able to go from an idea to a lump of metal in under 15 mins!
I've got a CNC Mill & Lathe too - but barely use them these days. Most jobs can be turned into something cut. folded, welded.

Likewise, anyone wants bits cut I'd be happy to assist. For free, if you supply the steel!

 

[SimonRafferty]

Looks great so far!
I've not tried plasma cutting Copper - I don't know why it didn't occur to me! I could have made a much neater job of some of the interconnects.

In response to your question about bolts:

The further apart the two metals are on the chart, the more electrolytic corrosion they will experience. (search for "Metal Electrolytic Potential" for a better list)

The terminals on the Hyper 9 controller 'look' like they might be Nickel coated. Tin (Solder) is pretty close to lead on the chart. Stainless steel (active 303, 304, 316) also sits in the range between copper & Nickel.

So, Tinned Copper attached to Nickel coated terminals with A2 or A4 (304 or 316) Stainless bolts would likely be a good combination. I hope I'm right about that - it's what I've used!

Stainless (bolts in particular) have a habit of 'picking up' or Galling - but you can buy anti galling paste which largely stops it, meaning you can loosen them next time.