6x6 Oshkosh HEMTT
 

Hi everyone,
some time ago I started building a 6x6 truck, but I wanted it to be a little more scale. So here I am starting the new build, that will eventually (and hopefully) be an Oshkosh HEMTT- - -6x6!!!

I first started with the chassis plates- just 2 long pieces of thick aluminum

http://farm9.staticflickr.com/8306/7...7c6f859185.jpg

Leaf springs done too. I made them using thin aluminum, I hope they'll hold up. Looking good so far.

http://farm9.staticflickr.com/8176/7...64eb8b83f3.jpg

http://farm9.staticflickr.com/8439/7...cc3812e976.jpg

The leaf springs connectors and shackles are made out of cutting board, working well.

http://farm9.staticflickr.com/8435/7...267c5a37c4.jpg

Mounting an axle

http://farm9.staticflickr.com/8036/7...95ab61bc01.jpg

I plan on using the following with this build:
Saturn 27T motor (stock wheely king- that's what I've go right now)
RC4WD Hammer Transfer Case
RC4WD R3 2 Speed Transmission
Wheely King axles

As you may know the transfer case and the transmission are being used on the Trail Finder 2. What means my chassis should be as wide as the one of the Trail Finder 2. I've been told the inner width of that chassis is 86mm, can someone please confirm that or tell me the right length? Thanks.
I want to start building but if I guess the distance between the 2 chassis plates the arriving parts (tranny and transfer case) are not going to fit.

As I'm waiting for these parts to arrive as well as to another pair of wheels,
we are celebrating the new Jewish year. So I want to wish you "Shana Tova"- Happy new year, and keep on building!"thumbsup"

To be continued,

Yorai

Re: 6x6 Oshkosh HEMTT
 

Can't wait"thumbsup"

Re: 6x6 Oshkosh HEMTT
 

Managed to place the steering servo today:

http://farm9.staticflickr.com/8445/7...a2830f99ef.jpg

http://farm9.staticflickr.com/8308/7...1ca5e69d66.jpg

Current state with wheels on:

http://farm9.staticflickr.com/8457/7...47be88e213.jpg

I hope everything will arrive in the following week...

To be continued!

Re: 6x6 Oshkosh HEMTT
 

New parts!! New parts everywhere!!!

So today I got most of the parts I ordered (except the wheels), and build continued full speed- which means very slowly, because I'm not such an experienced builder :ror:.

http://farm9.staticflickr.com/8030/7...c23147d41d.jpg
(They are so beautiful :flipoff:)

First thing I noticed when I tried connecting the WK driveshafts to the transfer case is that they almost fit. The simple solution was to make the U-joints a little wider.

http://farm9.staticflickr.com/8310/7...07df0602a0.jpg

Snug fit.

http://farm9.staticflickr.com/8169/7...288c8b05ee.jpg

Next step was to mount the transfer case on to the chassis. As you can see I connected it upside-down. It is not such a big deal, but it shortens the wheelbase in about a centimeter.

http://farm9.staticflickr.com/8318/7...6882900754.jpg

With spacer:

http://farm9.staticflickr.com/8177/7...ec6ea8b256.jpg

Ahhhh, because I drill really wrong... :shock:

http://farm9.staticflickr.com/8458/7...862c993476.jpg

TaDaDamTamTam Transmission!

http://farm9.staticflickr.com/8039/7...96a92c861c.jpg

Lining up these holes was a real pain!

http://farm9.staticflickr.com/8035/7...1e82a7e1e3.jpg

I am going to work on the rear axles on the following days, se you soon.

To be continued.

Re: 6x6 Oshkosh HEMTT
 

Some updated had been made, and it's show time!

It took a while to figure out how to give the rear axles maximum flex and yet keep the driveshafts connected. The solution I came up with was to simply put two shock-absorber bodies like so:

http://farm9.staticflickr.com/8173/8...b57514520a.jpg

They limit the travel of the axles.

A link to keep the axles upright

http://farm9.staticflickr.com/8172/8...389362bdcc.jpg

Small servo controlling gear shifting. I broke another one while testing.:cry:

http://farm9.staticflickr.com/8319/8...2dab14b27c.jpg

Started working on the cab!! I assure you it won'tlook too good, but that's the way of learning.

http://farm9.staticflickr.com/8452/8...7ec7e48544.jpg

http://farm9.staticflickr.com/8034/8...89a0edaa0f.jpg

http://farm9.staticflickr.com/8317/8...c6b651c199.jpg

http://farm9.staticflickr.com/8178/8...7059901df3.jpg

That's all folks!

To be continued.

Re: 6x6 Oshkosh HEMTT
 

A little progress..
Wheels finally arrived! The chassis look and perform pretty well.
Some work was done on the cab, especially on the mount to the chassis, I'ts far from complete.

http://farm9.staticflickr.com/8042/8...22b904d7b3.jpg

http://farm9.staticflickr.com/8451/8...8325665d98.jpg

http://farm9.staticflickr.com/8041/8...4fd66bbb0d.jpg

http://farm9.staticflickr.com/8170/8...07e095391c.jpg

I need to get myself some more aluminum for the cabin, and another material for the bed, any suggestions?

To be continued.

Re: 6x6 Oshkosh HEMTT
 

I had an idea of what this truck was but I had to Google 6x6 Oshkosh HEMTT to see exactly what you are building. Looks great so far. I like the aluminum cab. Do you plan of welding/brazing it together at some point or just using hardware like it is now?

Re: 6x6 Oshkosh HEMTT
 

I'm going to keep on building the cab this way becaude I have no experience in welding or brazing. I actually think it will look quite good after painted :mrgreen:

Re: 6x6 Oshkosh HEMTT
 

I agree. The bolt heads all over the place will look neat. I look forward to your updates.

Re: 6x6 Oshkosh HEMTT
 

Slow progress, that's what I've got right now.

I took the truck out for some test runs that did they're job, helped me find some problems! "thumbsup"
The first and main one was with the front axle. It kept "swinging" on the leaf springs.
My solution was to add another bolt to let the spring hold better on to the axle:
Stronger springs!

http://farm9.staticflickr.com/8449/8...145c1b40de.jpg

The second problem was with the rear axles, the limiting spring-less shock absorbers were not aligned properly. I moves on side a bit further, hope it won't hurt its performance.

I also found the time to, finally, organize the electronics.
I think i'll improve the battery placement..

http://farm9.staticflickr.com/8181/8...e81323de41.jpg

I used lego parts to protect the cables.

http://farm9.staticflickr.com/8178/8...93554e4b1c.jpg

To be continued.

Re: 6x6 Oshkosh HEMTT
 

A long time with no update, soon.. soon... 8)

But in the meantime I have a small question for you guys.
While I was running the truck I was annoyed by the open diffs. I have the option of closing them on two axles, which ones are the one that should be closed?
In my opinion I should close the middle and front, but what to you think?

Re: 6x6 Oshkosh HEMTT
 

I'd lock the front surely.

But locking both rears seems like it'd cause handling issues, maybe some limited slip units.. but then again I have 0 experience with 6x6's.

Re: 6x6 Oshkosh HEMTT
 

Some updates :)

Got some aluminum sheets

http://farm9.staticflickr.com/8324/8...375da1bc06.jpg

http://farm9.staticflickr.com/8188/8...54aa367c02.jpg

http://farm9.staticflickr.com/8045/8...a3d4180a5a.jpg

http://farm9.staticflickr.com/8470/8...ce22e8c3dc.jpg

Started building the rear bed

http://farm9.staticflickr.com/8326/8...b51460d4bf.jpg

I used the body mount parts from my wheely king and made this

http://farm9.staticflickr.com/8185/8...20fd4d5b5b.jpg

http://farm9.staticflickr.com/8047/8...3f1b4829d0.jpg

(electronics will be arranged again with place for the battery)

As soon as I get some morebolts the roof will join in

http://farm9.staticflickr.com/8188/8...b9fa525a5c.jpg

To be continued.

Re: 6x6 Oshkosh HEMTT
 

Beyond cool, going to be following this.

Re: 6x6 Oshkosh HEMTT
 

Yoraish,
What an awesome build you've got going there! I think your fabrication skills are phenomenal.

Any postings of running video?

Cheers,
Todd

Re: 6x6 Oshkosh HEMTT
 

Thanks "thumbsup"

No running video yet. I'm waiting for my new servo to arrive, and then, hopefully, I'll be able to lock some diffs and give this truck some abilities!

Re: 6x6 Oshkosh HEMTT
 

I'm still waiting for my servo to arrive..
Meanwhile I take a look at that:

http://farm9.staticflickr.com/8208/8...4cb5078d8b.jpg

That's the wiring for the new servo, I got to this design after long searching and asking around.
It basically means the servo will be powered staight off the battery but controlled from the receiver ( red wire cut in the receiver end).

To be continued.