Tracked vehicle construction?

Elliot · Post by **Elliot** » Thu Feb 02, 2006 5:35 pm

You may be too late, Jafe. Looks like somebody has already built the KatzenjammerGøtterdammerungCrawlerRad!

Photographed in a Quartzsite, Arizona scrap yard a few days ago.

( I have a scanner! I have Photobucket! It works!!)

Elliot · Post by **Elliot** » Thu Feb 02, 2006 8:12 pm

All right -- as promised a long time ago: Here are The Katzenjammer Kids at the controls of their latest invention.

Zulegoona · Post by **Zulegoona** » Thu Feb 02, 2006 8:25 pm

Gosh , the picture makes me want to see it run up to the edge of a cliff and throw projectile

robotland · Post by **robotland** » Sat Feb 04, 2006 7:03 am

http://www.gizmology.net/tanks.htm

Just saw this on the MAKE magazine site this morning.

(The new issue's on its way....looks GOOD!)

dragonfly Jafe · Post by **dragonfly Jafe** » Tue Feb 07, 2006 8:47 am

Latest design for tracks now have me using "attachment chain" - really cool stuff, it is roller chain (available in industrial sizes) that have little flanges built into them that are perfect for mounting tracks to. The largest size has a 1-5/8" pitch, which is perfect for my needs (and the pins are BEEFY!). Plus, now I don't have to custom make my drive sprockets... everything is "off the shelf" now!

With a roller chain 3/4" high in the middle of the track as a road-wheel guide, I now will need pairs of road wheels seperated by ~3/4", but that should solve the issue of the tracks "smearing" side-to-side during turns, and greatly simplify construction (no welding on the tracks, just riveting). Weight should increase by only 10-15lbs for each track, but I think the advantages are well worth it. It does double the number of road wheels, but I can use cheaper wheels because now the load/wheel is also halved (32 road wheels now, so that is only ~30 lbs/wheel)

dragonfly Jafe · Post by **dragonfly Jafe** » Tue Feb 07, 2006 8:50 am

Elliot wrote:

You may be too late, Jafe. Looks like somebody has already built the KatzenjammerGøtterdammerungCrawlerRad!

Photographed in a Quartzsite, Arizona scrap yard a few days ago.

( I have a scanner! I have Photobucket! It works!!)

....thinking if it is possible to drive down to Arizona with a very large flatbed...wondering how much that much iron would be as scrap...this disease has to be treatable...someone help me!

Elliot · Post by **Elliot** » Tue Feb 07, 2006 9:02 am

Jafe, are you serious? They told me the property is being sold and will have to be vacated. A Ford Skyliner, two Beech aircraft, a Pratt & Whitney 28 cylinder radial engine.... All complete junk.

Elliot · Post by **Elliot** » Tue Feb 07, 2006 9:16 am

... and this thing.

dragonfly Jafe · Post by **dragonfly Jafe** » Tue Feb 07, 2006 9:20 am

...if I thought it were possible I would be, but even if I could afford to buy and transport a ~20 ton piece of scrap across the country, my neighbors would burn me at the stake (with the blessings of the city officials, no doubt). My back yard is already perilously close to being designated as a "superfund clean-up site", and I am currently short of excess cash, so I think this once I will refuse to listen to the voices in my head...

dragonfly Jafe · Post by **dragonfly Jafe** » Tue Feb 07, 2006 9:25 am

LA-LA-LA-LA-LA!

(me singing out loud, ignoring the evil voices that won't stop trying to convince me to dive off the deep end)

...but an M3 halftrack AND an M3 light tank...WOW!

Elliot · Post by **Elliot** » Tue Feb 07, 2006 9:50 am

Jafe, I feel your pain.

A while ago I visited a yard in Sacramento where a guy had accumulated a lifetime of surplus "treasures" from nearby McClelland AFB. He was being forced to clean it all out. As a friend and I walked around and bought a few tidbits, I commented to my friend: "You know, I am at risk for ending up like this myself." And my friend said "Me too." We did not laugh.

One project at the time!

dragonfly Jafe · Post by **dragonfly Jafe** » Mon Feb 27, 2006 12:51 pm

...here is a photo of the first bogie wheel prototype. A total of 4 of these are on each side, each wheel is rated for 35 lbs load, so each of these assemblies can carry 140 lbs (630 lbs per side including the 2 tensioning wheels).

The final plates are planned to be 1/4" aluminum (possibly with a more artistic cutout reminiscent of a certain theme camp's logo...) and the center spacers will be 1 piece instead of a bunch of washers, but this is otherwise it. In use an attachment chain (9/16" wide by .8125" tall with 2"x6"x1/8" aluminum flats riveted on alternate links with a 1.25" pitch, 1/2" between flats for 80% tread coverage) will be guided between the 2 wheels, and the wheels will ride on the outer edges of the flats.

robotland · Post by **robotland** » Mon Feb 27, 2006 2:17 pm

Off and rolling! Well done, Sir! I'll be keeping...uh...track of your progress.

Mozy bonz · Post by **Mozy bonz** » Wed Mar 01, 2006 4:51 am

bump!!

dragonfly Jafe · Post by **dragonfly Jafe** » Wed Mar 01, 2006 8:56 am

...well the first quote for attachment chain came back at $3000 (yikes!), but I had spec'd 2" stainless steel links (the chain will essentially be dragging in the Playa). A quick revision I can get 1.25" steel chain (with attachments for riveting the treads on every other link) for around $500. That costs a little more than I had originally planned for the tracks, but eliminates hundreds of hours of welding aluminum treads...I think it is money well spent! By dropping the link size I save almost 20 lbs in the tracks also...and the treads are now only 1/2" apart making the rolling resistance less for my 8" dia road wheels...

Now I have to make a fixture for drilling 2 holes precisely in a couple of hundred treads....and start doing hand exercises (around 500 rivets to do!) I plan on the tracks being done by april 1, and the drive sprockets done and the tracks mounted by may 1 (that leaves 1 month to verify bicycle power will work before deadline for powered vehicle registration if that becomes necessary to move this beast!)

Tiahaar · Post by **Tiahaar** » Wed Mar 01, 2006 11:46 pm

awesome Jafe! heehee I would like to have seen the $$$stainless chain out there though. soon I'm due to make a trip to a metal yard to get some chain myself but you are way out in front! hey but I did put new cranks, bearings and click-in pedals on my tandem horsetrike last weekend, will put up a picture over in the wheeled thread soon.

Chai Guy · Post by **Chai Guy** » Tue Mar 14, 2006 5:18 pm

for sale down the street from my house:

robotland · Post by **robotland** » Wed Mar 15, 2006 3:15 pm

Chai Guy wrote:for sale down the street from my house:

Oh....My...Goddddd.........IT'S BEAUTIFUL!!!!!!!

#1- Buy, restore, drive.
#2- Remove cabin, convert to electric drive and use as daily driver- Mount floatboat platform on treads and load on flatbed for playa travel.
#3- Install entire vehicle, as is, in cluster of three trees approximately 50' off the ground and add rope ladder.

how much, I wonder?

Chai Guy · Post by **Chai Guy** » Wed Mar 15, 2006 5:36 pm

Give him a call:

Chai Guy · Post by **Chai Guy** » Wed Mar 15, 2006 11:53 pm

These were military light personnel carriers. They are amphibious.
Driven by a Studebaker 6 cylinder 178c.i. gas engine.
Transmission is 3 speed manual with a 2 speed rear end.
Comfortably carries 7 including driver. Over 30,000 were made so parts
are easily found. Top speed is said to be 50 mph!

dragonfly Jafe · Post by **dragonfly Jafe** » Thu Mar 16, 2006 6:32 am

...something about trying to skid steer at 50mph doesn't seem right, wonder if they used some type of differential steering system also?

Chai Guy · Post by **Chai Guy** » Thu Mar 16, 2006 9:29 am

It's called the M29 Weasel, here are the sats:

http://en.wikipedia.org/wiki/M29_Weasel

robotland · Post by **robotland** » Thu Mar 16, 2006 1:36 pm

Chai Guy wrote:

Quit it!!!

Chai Guy · Post by **Chai Guy** » Thu Mar 16, 2006 3:08 pm

Chai Guy · Post by **Chai Guy** » Fri Mar 17, 2006 12:17 am

Anyone need tracks?

http://www.tonly.cn/en/product.asp

Mozy bonz · Post by **Mozy bonz** » Sun Mar 19, 2006 5:08 pm

dragonfly Jafe · Post by **dragonfly Jafe** » Tue Mar 28, 2006 2:39 pm

Came home today to a UPS delivery attempt notice, COD, for my attachment chain! So I should have it tomorrow, then the final fab of the tracks can begin. I still am trying to figure the drive sprocket out. 100# roller chain steel sprockets are $$$ and heavy. Like 50 lbs each! I may have to design and fab my own...I am thinking of using bolts to secure the drive sprocket to the drive shaft instead of keys. Any thoughts on that?

LeChatNoir · Post by **LeChatNoir** » Tue Mar 28, 2006 6:38 pm

Bolts will shear easier than keys when placed under stress, but I'd say for this application it'd be fine... or at least worth a shot. Its easier to drill for a bolt than it is to cut a keyway in a shaft and sprocket.

dragonfly Jafe · Post by **dragonfly Jafe** » Wed Mar 29, 2006 9:05 am

..your right, it's the cross sectional area of the shear plane that defines shear resistance, not the overall length...so a bolt does have a fraction of the shear resistance that a key does...guess that's why they use them...

I ordered 2x 16" long 1" dia minibike axles with keyed slots for my drive shafts. They will sit in the 2x go-cart live-axle bearing supports I bought. A 100# roller chain sprocket around 10-15" dia will go on the outside end, and the power sprocket and the steering sprocket will go on the inside end. The massive type-a roller chain sprocket will be mounted using 4 bolts to a 4" minibike hub that is keyed to the axle.

The parts are arriving, the build fund is draining...

geekster · Post by **geekster** » Wed Mar 29, 2006 9:26 am

Sounds like you have one heck of a fun project going there. Good luck with it and I am looking forward to seeing it on the playa.