My HEMTT build
 

Well, I have most of all the parts I need to get started so i thought I will start my thread. I am building an HEMTT M983 tractor. This is an Oshkosh
military equipment hauling tractor. 8x8 dual axle steering. This should be a fun build.
http://i671.photobucket.com/albums/v...G64/m983-1.jpg
This is a picture of it. Once I am finished I will also be building a goose neck trailer for it. Something like a Trail King. I will be using this vehicle mainly as a tank transporter. Although this truck really does not have the capacity in real life to haul tanks, I still like the looks and concept of it being a tank transporter. Oh I forgot to mention I have a large collection of 1:16 scale rc tanks. Mostle Tamiya and Tamiya powered. I'll put some pics of them up in the tank section, so here we go.

Re: My HEMTT build
 

Two of my favorite HEMTT builds:

http://www.rccrawler.com/forum/1-9-s...oller-8x8.html

http://www.rccrawler.com/forum/1-9-s...not-hemtt.html

Re: My HEMTT build
 

Hey Thanks farmboy. I really like the second build. It gave me some rally good info on how to do the suspension. I am new to this so that really helped. i will be making most of my own brackets too this is invaluable info. Thanks again.

Re: My HEMTT build
 

That is gonna be a great build. I have driven these when they were a part of my FA unit. They hauled the beans and bullets.

Re: My HEMTT build
 

Started the mundane task of assembling me TLT axles. I have a locker for one but havent got a clue as to how to install it. I have some pics I'll get up tomorrow.
I noticed on one of my diff carriers there is a tapped hole in one side where the axle goes through. Is it possible to lock the axle by installing a set screw in this hole and is that what it is there for? I also need to get one more pinion gear. I did not do an entire inventory of all the Axle parts bags because I knew there would be something i missed or needed so I can do 3 of the 4 axles. So far so good. Having fun. Not quite like building a tank from a kit.

Re: My HEMTT build
 

If the side of the diff with the ring gear has a hole in it, that is a ring gear for a high lift or a crawler which will work in a TLT. The only difference is the TLT does not have the hole in the shaft for the threaded lock pin. Here are some pics of the high lift axle to see how the lock works.

http://i574.photobucket.com/albums/s.../difflock1.jpg

http://i574.photobucket.com/albums/s.../difflock2.jpg

Travis

Re: My HEMTT build
 

Wow , thats cool. Thanks Travis. So does this mean I can lock the axles with this diff?
This pair was bought on Ebay because they where already set up for the troguh drive axle. Came in parts that I needed to assemble. That is why I need a second pinion gear and bearings for the second drive through axle. Cant wait to get these done so I can start on the suspension parts and then determine my frame length. This will also help with scaling it. This will be in between normal scales from what I can tell so far.

Re: My HEMTT build
 

I have a few pics of the parts pile.
http://i671.photobucket.com/albums/v...4/HEMTT100.jpg
http://i671.photobucket.com/albums/v...4/HEMTT098.jpg
http://i671.photobucket.com/albums/v...4/HEMTT097.jpg
http://i671.photobucket.com/albums/v...4/HEMTT096.jpg
http://i671.photobucket.com/albums/v...4/HEMTT093.jpg
http://i671.photobucket.com/albums/v...4/HEMTT092.jpg
http://i671.photobucket.com/albums/v...4/HEMTT091.jpg
http://i671.photobucket.com/albums/v...4/HEMTT090.jpg
http://i671.photobucket.com/albums/v...4/HEMTT088.jpg
the first pic is of the diff locker which I have no idea how to use.

Re: My HEMTT build
 

i know I should use bearings on all this rolling stock but at the moment the budget is shot in the A$$. I can always upgrade them in the future as well as add more lockers.

Re: My HEMTT build
 

It's all looking good and we all know about that dirty phrase ... the budget. :eek:
















~ Jeff

Re: My HEMTT build
 

Hey Greg, read thru this thread, and it will answer your bearing question.
http://rctruckandconstruction.com/sh...=axle+bearings
Hope this help's! Later, Neil.

Re: My HEMTT build
 

I love watching these builds. Cant wait to see more
Scott

Re: My HEMTT build
 

Thanks Niel. I am not using the Tamiya 3 speed tranny so that is not an issue. The bearings I'm referring too are for the axles. I generally would always put bearings in the roadwheels of my tanks as should be done with these axles but as I said at the moment the budget is shot so I am continuing with everything I can for now.

Re: My HEMTT build
 

Hey Greg, further down in the thread Lil Giants Joe, was talking about using bearing's on the end's of the axles and leaving the bushing's next to the diff.. And Freddy Gear Drive had some comment's too! Have fun with the project!
Cheer's, Neil.

Re: My HEMTT build
 

I also had to make custom wheel hexes. The Panther wheels use an 8 mm hex. Try finding that one. LOL
What i did was get some aluminum 4/40 x 3/4 standoffs and cut them down to size. I then drilled them out to fit over the output shafts. Then i drilled them to accept the pin. They work great.
http://i671.photobucket.com/albums/v...4/HEMTT225.jpg
http://i671.photobucket.com/albums/v...4/HEMTT226.jpg

Re: My HEMTT build
 

Well, progress has been a little slow as most of this is new but i have completed my axles. i did have to make custom wheel hex's as i had said and they work great with the Robbe Panther wheels. Now tomorrow i am going to start on the suspension system. not quite sure which way i'm going to go yet but i have gotten plenty of ides from alot of you guys. I'll get some new pics up as soon as more progress has been made but things are progressing nicely.

Re: My HEMTT build
 

Its going to be a pretty impressive machine when its done. :)

Re: My HEMTT build
 

Will the steering radius be affected with locked diffs? I'm thinking with this many wheels on the ground you should have traction most of the time.

Re: My HEMTT build
 

I'm not going to lock any of them at the moment. I need to see how all the gearing ratios work first . I'm also thinking of using a motor doubler just for some added grunt. I'm not really building this as a crawler although that is what most of this build really consists of but a hauler for my RC Tanks, Some of them are over 15 pounds, so we are looking at a lot of accumulative weight.

Re: My HEMTT build
 

I did hit a small snag with the length of the leaf springs I have. The tire diameter I'm using is a little tall. Actually a little closer to scale from what I can see from some of the other builds like this i have seen so I need to fab some lengthened brackets or use a different type of suspension. The budget is still condition Red so anything I need has to be made. Keeps it interesting.

Re: My HEMTT build
 

Just for some reference as to what this will be pulling here's a couple of pics of 2 of my heaviest tanks
http://i671.photobucket.com/albums/v...4-11-10001.jpg
http://i671.photobucket.com/albums/v...4-11-10004.jpg

The Tiger on in the first pics is over 15# the Panther second is just under 13# so factor the Tractor, trailer and tank we should be close to about 35# fitted out.

Re: My HEMTT build
 

Oh here's a pic of a really cool Marine version it is called the Mk48. It is articulated and the front section is driven aswell as the trailer by means of an articulating drive shaft from one unit to the second.
http://i671.photobucket.com/albums/v...sh_mk48_l3.jpg

Re: My HEMTT build
 

The Marine's had a few in Subic Bay, Phillipines during Desert Shield/Desert Storm. I spent 6 month's active duty there.
I alway's wondered about tire wear on that version.
Cheer's, Neil.

Re: My HEMTT build
 

From what i am told the front wheels do steer on the drive unit. It is not just turned by articulation as the driving unit can be driven with out the trailer. they dont go far with them as you could understand they would not be all that stable.

Re: My HEMTT build
 

Hey Greg, the front axle does steer and there is linkage that connect's to the articulation joint. They claim the trailer can be disconnected from the front or tractor, and drive around. I never did see it happen. I did see a marine turning the steering wheel, while stopped, that scrub's the front 4 tire's something fierce. I don't know if there's a way to lock the suspension out when bobtailing? A little bit of digging, maybe I can find a Tech manual for one.
Cheer's, Neil.

P.S. there is a strut for suspension lockout. http://en.wikipedia.org/wiki/Logistics_Vehicle_System

Re: My HEMTT build
 

Thanks Neil. This was the version I originally wanted to build but I'm already chewing on a pretty big piece as it is. LOL. I will sometime in the future build myself one of these Mk48's. I just think there really cool.

Re: My HEMTT build
 

I alway's thought they were neat, and an improvement on the older dragon wagon's.
Interesting, that they only get 2 mile's per gallon.
Cheer's, Neil.

Re: My HEMTT build
 

Well the Mk48's use a specific Detriot turbo and supercharged engine. I can only imagine how awesome they must sound.

Re: My HEMTT build
 

The Mk48's use a special Detroit turbo charged AND supercharged engine so I can only imagine how awesome they must sound.
I unfortunately haven't been feeling too well this week so haven't gotten much done.
I want to get back to it tonight and tomorrow. One thing I could really use is a good drawing with better dimensions and angle indications. The ones I find are to low of a resolution so I cant blow them up to see them well enough.

Re: My HEMTT build
 

Made a little progress. i have worked out my suspension method that i am going to use and started mounting brackets and leaf springs to the differentials.
I also have my frame rails cur to length with the axle center lines marked.I plan to get the rear axels sets up to this point tomorrow and then complete the layout of all the holes needed in the frame rails. time for some drilling and tapping.
One darn thing I forgot to order when I got all my M3x.05 button head cap screws was nuts for them so i have been scrounging around up until now. Gonna have to get some ordered.
http://i671.photobucket.com/albums/v...4/HEMTT342.jpg
http://i671.photobucket.com/albums/v...4/HEMTT343.jpg
http://i671.photobucket.com/albums/v...4/HEMTT343.jpg
http://i671.photobucket.com/albums/v...4/HEMTT341.jpg

Re: My HEMTT build
 

I hit a little snag that have been slowing things down some what. I have Wedico leaf springs but they are about 1 inch to short for the application i want to use. I asked in another post for the dimentions of the Tamiya leaf springs and they are exactly 1" longer. Perfect. Now i just need to find the Tamiya leaf springs and mounting brackets for them. Any one have an idea of where I could get these parts from, or have a good list of bag components so I can order the correct parts?

Re: My HEMTT build
 

Are you looking for the tamiya semi leafs or the HL leafs???

--Dan

Re: My HEMTT build
 

I'm looking for the Tamiya Semi leaf springs. I have 4 all wheel drive axles so I need 8 complete springs. I do not know if one complete axle is considered a set or one side so I am just saying 8 complete springs.
For the moment the project is shelved partly because of the springs and partly because I have tanks I have to complete for our battle days with my club and the events at the Danville Armor Museum.

Re: My HEMTT build
 

Hi

Thanks for posting your build so Far, keep the pics coming.

Any chance you could post a parts / supplier Source List ?

Thanks Again for the Pictures, Really Nice build, what again is your Motor/gearbox for this?

George

Re: My HEMTT build
 

I have the RC4WD single speed gear box and a drop down transfer case. I will be adding a doubler to use twin 540 motors.
I got some parts from PMD, Robbe and ebay basically thats it.
I will be using the simulated air ride suspension for the build as I think that will look and work the best , they are from russislouds Bone Yard.

Re: My HEMTT build
 

Looking very nice, love the hermits.

Re: My HEMTT build
 

I really like the HEMITT you are building it looks great, can you please tell me what type and where did you get those awesome tires and wheels if you don't mind me asking.







Thanks
crazy4yachts