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Old 12-17-2012, 01:39 PM
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mooman007uk
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Default formula offroad, Mkll twin build, pic heavy

with a bit of time on me hands and a borrowed, from a buddy, mini lathe/mill combo i started on foff Mkll build...
will be powered by an obr 57cc fullmod twin dialled for torque,
4130 chromemoly tube chassis, 4 link suspension and solid axles front and rear[8D],
kalee tires as they weigh half of what rampig ones do at 740gr, shaved and i think the hpi 5t sand buster paddles glued on,
either drop pitman arm steering set up or toying with the idea of piston to piston hydraulic steering...i'm on the hunt for an oddified tonegawa ps050 if anyone has one or knows of one.
pipes will be hacked up pocket bike exhausts.
motor will be mounted up front lengthways with a simple pinion and spur with jack shafts. splined driveshafts from a honda hru216 mower for centre shafts.
aluminum and steel body panels

just 'bout covers it.

first up the hardest part...axles. been trying to figure these out since my last build...was coming up short until i scrapped aluminum and started thinking good ol' steel.. then i came to me,so procured the needed machine and got started.
using rampage centre diff spool and pinion front and rear.

started with this...each one is a half...

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ended up with this

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machined a vertigo 5b rear hub as a pattern to get the correct bearing position for mesh

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milled holes

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then set about making pinion bosses from aluminum as well as wheel hubs and steel hub flanges

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so far so good, only manged to bugger up one pumpkin half...the last bit too...3 1/2 hrs machining down the drain...being a small lathe 1mm cuts are the max even with carbide index bits.

next was to determine how big the thing is going to be and came up with 20" from end of hex on the wheel adapters, 26" with tires and 26- 28" wheelbase axle centre to centre,,should look scale then with the 8x5" kalee tires.

so cut some thick walled 4130 tube and voila axle housings

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now working on the rear axle shafts...using pig/5b outdrives welded to cut to length hurrax shafts, will be no pins or cups to break, one solid shaft...one all the bits are finished i'll take them to the local foundry to reset the desired hardness and temper.

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the fronts will be hurrax cvds mated to pig outdrive

so axles are just a postman (for some hex sleeve i need), bit of machining and welding away
rear axle with shafts weighs a hair under 1.5kg (3.3lbs) which = a rampage tire, so with 2 kalee and the axle it= 2 pig trotters....the whole build i hope to scale at no more than 18kg (39.6lb) wet, hopefully get in around 16kg.
now that i've been working on these i reckon i've figured how to make the pumkins from aluminum which would enable cheaper and easier production...however i need to test these first then do up a set of alloy protos and test those...hope to bring affordable solids to market if there is enough demand for an outsourced production run to be worthwhile.

can't start on the chassis until my engine comes and that can't be sent until OBR gets their awaited delivery from rcmk..still 1-2weeks[&o] but at least i'll have everything i need here by then so should only take a week or two to complete...think i'll end up power coating this one as well.