6x6 Kenworth Day Cab (King Hauler)

[NRS91]

Now winter is here I decided to get back into the RC hobby again.
I wanted to build something that I could use at the scale crawling and scale trucking events so it had to be 6x6 and I wanted a decent turning radius so day cab was also the order of the day.

I started with a King Hauler kit, Globeliner chassis rails, Carson 20% gear reduction and some extra inner dually wheels.


I also got some front leaf springs and a HD rear crossmember from KK Trucks


TLT-1 Front axle was sourced from eBay


Here you can see the King Hauler chassis rails vs the Globeliner ones


The build begins, took me a little while to get my head back around Tamiya instructions... well it has been 15 years since I last built one.


KK Trucks rear crossmember is a nice bit of kit but very fiddly to assemble with chubby fingers!


Chassis, axles and suspension all test fitted.


Test fitting the transmission with a Lesu transfer box, just not enough room to make it all work unfortunately.


The custom rear crossmember has allowed me to move the axles back 18mm to get the 5th wheel in a more realistic location.


Day cab conversion panel 3D printed and test fitted.

[NRS91]

The front springs didn't quite line up with the mounting holes so KK Trucks printed some new ones for me, they fit a treat!


I wasn't happy with any of the transfer boxes I could find so I decided to make my own with 2.6:1 reduction.
Here is the V1 Solidworks CAD mock up.


1st prototype transfer box printed and test fitted. Gear mesh was too tight, too close to the cab floor and holes slightly out of line.


Version 4 of the transfer box case... All bolts up snug now.




Transmission is on 20mm raised stand offs.




Just got to wait for the props to turn up now!

[Bo Wallen]

Welcome back! The stripes newer leave a zebra...........A nice little project you have going, keep it going and let's hope we meet at some event.

[NRS91]

Thanks!
Hopefully this transfer box idea will work out so I can get it rolling!

[NRS91]

Little more done today!
Looking for somewhere to hide a 2S Shorty Lipo so I downloaded this toolbox from Thingiverse and rescaled it.
Had some 3D Printer issues but hopefully I the next version will come out better!


So the truck wasn't just driving around alone I bought a cheap Britains Big Farm Kane lowloader and promptly chopped the drawbar off to fit one from PiggyTaylor RC so the Kenworth can tow it!


Hitch close up.

[bigford]

Is the transfer case a reduction unit or direct output
If its 1:1 I'd install a slower motor now.

[NRS91]

Originally Posted by bigford

Is the transfer case a reduction unit or direct output
If its 1:1 I'd install a slower motor now.

The Tamiya 3 Speed has the Carson 20% gear reduction plate and pinion on it and the transfer box is 2.6:1 reduction, should crawl well!

[NRS91]

So the prop shafts arrived!


Had to trim the two bottom casing bolts off for clearance:


I won a Wedico Low Loader #3 off eBay and a friend gave me his old Heng Long Leopard as a load:


Fits a treat!


Remade the cab rear wall and made a rescaled Thingiverse chain locker to house a 2S Shorty Lipo. I printed some rear wings off ThingiVerse but they wouldn't fit with my Lesu tyres so I designed and printed my own which use the damper mount holes to mount to the rails.


Nice and neat!

[Bo Wallen]

Pretty good build right there. Happy haulin'
P.S. If you want better steering, move the parallel steering rod behind the axle, it will turn much better.

[NRS91]

Thanks for the tip, I assume you mean swapping the hubs on the steer axle so the track rod I'd behind the axle to make the ackermann angle correct?
What would be the best way to make the drag link from the steering servo work afterwards?

[Bo Wallen]

Yes, that's correct, I put the servo laying down flat, inside the frame rails and use the same point you got now. If it's tight, there is a low profile servo on the market you could use also.

[NRS91]

Have you got any pics of your set up Bo? Would be handy for inspiration!

[Bo Wallen]

Originally Posted by NRS91

Have you got any pics of your set up Bo? Would be handy for inspiration!

Out of town until Friday. I will make some pictures when I'm back.

[NRS91]

Originally Posted by Bo Wallen

Out of town until Friday. I will make some pictures when I'm back.

Cheers that would be great!

[Bo Wallen]

I was looking into some older pictures and found these ones.

[IMG]IMG_1871 by Bo Wallen, on Flickr[/IMG]

[IMG]IMG_1870 by Bo Wallen, on Flickr[/IMG]

[NRS91]

Originally Posted by Bo Wallen

I was looking into some older pictures and found these ones.

Cheers Bo, I was wondering more about the drag link from servo to hub?

[Bo Wallen]

Originally Posted by NRS91

Cheers Bo, I was wondering more about the drag link from servo to hub?

That draglink can be mounted on top at either side of the hub. The parallel rod can be mounted under the springs with a lesser bend.

[NRS91]

Originally Posted by Bo Wallen

That draglink can be mounted on top at either side of the hub. The parallel rod can be mounted under the springs with a lesser bend.

I see what you mean yea, Just wondering if the servo would have space to sit under the motor without the axle hitting it on full compression

[NRS91]

Whilst I am waiting for some parts to come for the truck I turned my attention to the Wedico #3 Low Loader.
Being 1/16 scale its only 160mm wide and with the King hauler being 200mm wide I decided I needed some "greedy boards" for the trailer, which will also help support the Heng Long Leopard better!


The centre greedy board didnt quite fit nicely so will have to be reprinted at a later date (they were a 16hr print!)


The tank still overhangs a little which is to be expected but it is now much more stable! (At the front it still sits on the bolts a little though)

[Bo Wallen]

Originally Posted by NRS91

I see what you mean yea, Just wondering if the servo would have space to sit under the motor without the axle hitting it on full compression

The front axle does not move up very much, and if you put the servo up to the gearbox, I think it will work fine.