My Senior design project - a "Swamp Thing" tracked vehicle clone

[Garauld]

The blue thing - yes. I plan to use them for dome lights.

 

[PILOON]

What kind of system did they use for steering it? Mine has brake steering.

I spent the last couple of days assembling the grab rails:

View attachment 628988 View attachment 628989

My DIY tractor cab uses the same style of insulation, good thinking.

As to the VW based 'snow machine' they somehow split the differential and inserted a casting that sported a variable drive belt unit very much like snow sleds use.
Never opened it so don't know details.
Steering was by mechanically opening or closing one set of flanges.
It even used the original VW car steering.
Actually every single removable component on a VW chassis was incorporated in that sled machine.
Being designed for Alpine use it had an escape hatch in the cab roof in case of avalanches.

 

[KubotainNH]

The external grab handle is a nice add-on. Clean.

 

[Garauld]

I spent today setting up a production line for making the track bars and wheel guides. I only need 126 track bars and 252 wheel guides. It is a good task for crappy weather days....

 

[Garauld]

Hi gang - I was playing with a piece of my 5/16" belting trying to home in on a pitch distance for the track bars. I ended up using 84mm (3.307") as a value. I attached a photo of the bars placed around my drive sprocket. Tomorrow, I plan to attach the second 5" belt.

 

[jmc]

This is the part I've been waiting for!

Are you going to give us a "tour" of your shop?

 

[Garauld]

Are you going to give us a "tour" of your shop?

Not until after I clean it.

 

[ArlyA]

Channel style cleats lost favor some years ago. They fill with ice or mud and loose much of there traction..

Hi gang - I was playing with a piece of my 5/16" belting trying to home in on a pitch distance for the track bars. I ended up using 84mm (3.307") as a value. I attached a photo of the bars placed around my drive sprocket. Tomorrow, I plan to attach the second 5" belt.

View attachment 629988 View attachment 629989

 

[Garauld]

I plan to add a filler strip that will leave a bit of the two sidewalls of each track bar exposed. Also, thanks to ArlyA, I think I will be using his suggested splicing method as shown in my revised design:

 

[ArlyA]

Here is some examples of tire guides. They should be rounded to keep from damage the tires. Turning while on a hard surfaces is really tough on sidewalls. The tires on snowcats are not normal but are commonly foam filled, highly belted and thick treads and side walls. You can still get air filled but most today seem to be foam filled. They live a hard, hard life.

 

[dougtrr2]

Not until after I clean it.

So does that mean never?

Doug in SW IA

 

[Garauld]

OK, I cleaned it up a bit...



JK... :ashamed:

 

[airbiscuit]

 

[Garauld]

I had some brake lines made up and installed them. I will fill them, bleed them and try them out soon. Working on the tracks and front bumper next.

 

[PILOON]

From what I have seen your project is not 'thing' but rather a work of art.
Very nice!

 

[ArlyA]

Garauld is doing a nice job on it. Same as I'd be doing if it was my project...

 

[Garauld]

Now this is what they call a bumper: :dance1:



I also made up some track bars:

 

[carbon]

Hi Garauld, great build you have going here. I signed up to this forum just to follow along!

I am curious about your brake steering system, especially since there was some mention of welding your differential spider gears.

Great work!

 

[Garauld]

I am curious about your brake steering system, especially since there was some mention of welding your differential spider gears.

Hi Carbon - thanks for the kudos. It's a fun build. In reference to your curiosity there is a discussion about this subject early in the thread. Another reader noted that spider gears are not designed to handle this duty (which I agree with) and should be welded up. There are two ramifications of this: 1) I don't have to lock the other axle somehow (a good thing) as the Echo uses an open differential in the transmission, 2) the overall speed of the vehicle is reduced by 2 (not so good). I now calculate the top speed to be about 18 mph at 6000 rpm.

 

[carbon]

Ok so there are two differentials in your drivetrain; the one in the echo transmission which would have driven the front wheels since its a transversely mounted engine, and then you are connecting that transmission to a driveshaft to power your Rav-4 differential with the brake-steer system, right?

So the transmission differential is the one you are welding up then?