question about tracked vehicle

[pat32rf]

I would aim for a heavier axle than the small Jeep unit but in theory you should have no problems. Used to steer dune buggies this way, ditto with 9n Ford tractors.... Use the KISS principle. Separate emergency brake cables can do the job....

 

[BHD]

I am sure it would work.

but I had once up on a time a swather, that used belt drives, that really fascinated me, at it set up you had two handles one for each drive wheel, by either moving back or foward (do not rember any more) they would lock (over center) and provide power to the given wheel, foward, (guess pushing foward)
by rocking the other way it would put that wheel in reverse by working a jack shaft, it did not lock into reverse.

but the really beautiful designed feature was the way it would allow one to make Small changes in the variance of the driven wheels, one lever the right was able to tilt right and left, and when both wheels were locked in gear, (the belts were the clutch as well), there was center pulley that would slide and in the process of moving right and or left, it would change the ratio of the drives to each of the wheels, (just as a variable speed clutch works) but insted of a clutch it would vary the ratio between the wheels so one could make easy and flawless course adjustments), this was high speed and all the reduction took place after this.

but I was more under the impression that the better tracked units used a planetary clutch that had a brake on the outer drum of the clutch, instead of brake steering.

one more thing I saw and have always wanted to try, was to use a large used tractor tire, with the bulk of the side wall cut off and then stretch the tire over a set of tires for the track system, similar to this system http://www.otico.com/local/cache-vignettes/L400xH271_photo_terraflex_syst-4d044.jpg but the tire would still curve and fit over rubber air filled tire,

 

[pat32rf]

A set of planetary gears on each axle would no doubt be the best plus it would give you more gear reduction but it will also add weight, cost and complexity. I'd vote for a heavier third member such as a Dana 60 from a 3/4 ton truck.....

 

[Renze]

I don't know anything about tracked vehicles but I know the rear diffs on my 4WD and Kubota only becomes 'one wheel drive' when one wheel loses traction and starts spinning. Presumably on a tracked vehicle 'loss of traction' would be rare so an ordinary diff would be OK to use and the vehicle would travel straight in most circumstance. (But I'm just guessing)

As done in the era of the 8N and others, when difflock wasnt standard, you could just countersteer (brake the spinning track) to regain your traction.
My previous Volvo had this TRACS system, it is an addition to the ABS system, that works in the same principle using the same sensors, modulator and pump, but brakes the spinning wheel. It worked perfect on ice. Last week i was stuck in a tunnel, couldnt get out in the snow. Then i really missed that feature on my current S70. I did get out by spinning the tires at 180km/h melting the snow underneath.


I think that Jeep axle will quit on you, with that much traction: Lets not forget that the Jeep axle was helped by another axle (the front axle) to put its weight into traction. Right now you'd be moving all that weight, with more traction because of the tracks, over just one differential.

 

[whitworthsocket]

Early Bombardier track vehicles used ford rearends turned upside down (because they were front mounted) and indepentant braking. tracked vehicles don't have the slippage that a wheeled vehicle does so the differential will normally divide the power pretty much equally. With independant braking you simply apply the brake on the spinning track & power shifts to the other. The power to either track is determined by the brake applied to the other track. MikeD74T[/QUOTE]

As Mike says do a websearch for Bombadier Muskeg J5. or try Muskeg Tractor
They look like mighty tough machines they had chrysler motors and differential drive.

What size of tracked vehicle where you looking at?
Regards Whitworthsocket

 

[JoelD]

I would definatly study the case 310 I also had one and it basically does what you want to do

I think your biggest struggle will be the rails and tracks

ripsaw maybe anl to help you there

building a tracked anything is not easy maybe a lot easier to purchase something already built

one point on hydraulic drive that I realy like is any motor can spin a pump and you avoid many of the mechanical complications

Joel


good luck

 

[whitworthsocket]

After re reading the initial post. I did a google search for a GI weasel.
after 85 entries I finally found out that it was an M29 weasel made by Studebaker.
I then found this site.

Welcome to M29c Weasel.Org

I believe that these guys would be able to categorically answer your question

Regards

 

[jet500]

Hi, I'm working on the same project

It took me 2 years of planning and I'm ganna order the parts this week

Things that you need to know

you have to do alot of ratio calc to get the right speed

order a custom track with sproket and idel wheel that fit the track

There is speed rating on the track

my project will be a twin turbo supra engine vvti with r154 5 manual speed trans

custom made tracks based on huggland bv206 400mm wide 8.10 meter long each


I'm ganna use a 4x4 diff with a twin rotor twin calper on each side for turnning

brake will be mounted on the shaft side with a twin rotor caliper


the diff will be mounted in the front and the engine in the back

wish me luck


thanx

 

[Renze]

Jet500, drive sprockets on the front means that you'd have to put idlers on the back: When you need a lot of traction, the upper part of the track is tensioned, which also un-tensions the idlers. In other words, it gets hard to keep track tension.

Its better to put the drive sprockets at the back, so the tensioned distance from drive sprocket to where the track touches the ground, is minimal, and the unstretched part running over the top, is maximal.

 

[David Devuono]

When I had my Unimog, much of the offroad torque came from the 2:1 Hub gears. (that 7,000 lb truck only had a 9" ring gear) A jeep rear end driving a 12" sprocket is like a 2.5 times torque muliplication over a 30 inch tire. If you have both a dana 60 and a jeep model 35 rear end laying around, use the dana 60. Otherwise I would just use what I had.

I am also starting my tracked vehicle in a couple of weeks and will start a new thread.