# Unatracs, Homebuilt Tracks, on SortofaSamura



## deepmud

I have a 1987 Suzuki Samurai - or it used to be. I've messed with it a lot over the years, being one on the early diesel conversions about 10 years ago or so back (maybe it was 15 years ago...) anyway - it was a 1.9td Samurai that I drove to work every day. Great rig - 27mpg at 65mph on 35" tires. AND I had some homebuilt tracks from a guy in Maine. They had "issues" but I did use them some.
Somehow it was the "year with no snow" that I bought them. This is December in Alaska:





Eventually I got some snow:





It worked pretty well but the track carriage had an Achilles heel. Weak Spindle, weak design - they've been sitting while I gather parts for the redesign.

I got another set of tracks, some of the original, 1970, Unatracs, in trade.

Here they are on a old Jeep Wagoneer.




Of course, I never leave well enough alone - in the intervening years the Samurai got stretched, lifted, coil suspended, new axles, new Toyota driveline, and a "new"diesel, a TDI with a manual pump and big intercooler. No longer commuting, it's a trailer queen.

I have the same tracks on my Samurai, with about 1/2 the weight. Video is of me trying them out, running a ditch (about 4 to 6 feet deep - but you know ditch snow is pretty packed compared to normal snowfall)





My next project is to make a topper that allows me to haul the wife and kid ( the two older ones are out of the house ) and maybe some friends kids along in comfort.

I hope to be out on the trail near Willow this next Sunday to watch the Iditarod Restart go by. If it works well I'll take some trails out in Trapper Creek/Talkeetna next.  I even got a flashing yellow beacon so the snowmachines don't run into me.


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## undy

It looks like the Jeep, at least, would benefit from locking diff's.


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## redsqwrl

I am intriqued with your project on a couple of levels. I have a full bodied imp and a bombi that will some day be articulated. I am not a purist so a VW Diesel may wind up in either machine, the Audi five cyl and mercedes inline six are possibilities as well.(just because I am hoarding the donor cars)

*The TDI to Toyota. *

Is that a acme kit? 
Is all the suzuki items removed with toyota in their place? (I had a Suzuki brute lj-20)

*The bending spindles.*

Design problem or extreme usage issue?
Would a axle upgrade cure some of the support issues (Dana 44's from a scout)

*The air locker topic:*

Would you be able to turn a locked, welded diff. (i think so)

Mike in WI
Thanks for sharing. all things tracked seem to occupy my brain these last few years.


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## deepmud

*Re: Unatracs, Homebuilt Tracks, on SortofaSamurai*

I am a "track'd truck addict" - I saw some Unatracs being tested here in Anchorage when I was a kid - we were just driving by, and there was a Blazer and a Suburban cruising out of the road in the deep snow (in a place now occupied by a subdivision :) - this would be .... I'm guessing 1974. I was 5 or 6 and it stuck with me. I would draw "custom 4x4 vans with tracks" on graph paper for years to come, lol. 

The Unatracs I have now could possibly be one of the sets under test, but I think they're older as they are of the "first generation" style, without up-turned ends on the assembly.

My collection of track pics (at 130 thousand-plus hits!  )
http://www.supermotors.net/registry/7029/62149



redsqwrl said:


> I am intriqued with your project on a couple of levels. I have a full bodied imp and a bombi that will some day be articulated. I am not a purist so a VW Diesel may wind up in either machine, the Audi five cyl and mercedes inline six are possibilities as well.(just because I am hoarding the donor cars)
> 
> *The TDI to Toyota. *
> 
> Is that a acme kit?
> Is all the suzuki items removed with toyota in their place? (I had a Suzuki brute lj-20)



Yes - www.acmeadapters.com - I had Jeff's Beta VW-Toyota adapter for awhile - it was just slightly off, and caused me much grief. The clutch would overheat while just sitting there idling due to the slip caused by the offset of the motor/bellhousing. My new one is perfect. That's Beta for you tho' .

I had a KelTec kit, provided by RockRoadOutfitters before that. It worked fine, and for a lighter rig, off-road only, I'd have stayed with it, but my 1.9td was turned up to about 12psi boost and enough fuel that I had to keep an eye on EGT on steep hills - and I broke 5th gear on 3 Suzuki transmissions (all used - ACME has had good luck with rebuilt units and synthetic oil). I think 35" tires and 65-70 mph highway commuting 100 miles round trip per day was too much on the small transmission you can tuck under one arm and walk around with.

So I went with the Toyota when I acquired the 1.9 TDI-M (because 150ftlbs/1500rpm stock and I was turning it up) . Looking back I could have just gotten another Suzuki transmission, because I turned my rig into a trailer queen, so the highway speeds aren't a factor anymore.

So my rig has a Toyota W56 trans, and Toyota Axles, and 5.29 gears (the diesel handles 39.5's and the 4.11's fine but idles too fast (in mph) for tough trail work. I really should get some Marlin Crawler gears (4:1) in the transfer case.




redsqwrl said:


> *The bending spindles.*
> 
> Design problem or extreme usage issue?
> Would a axle upgrade cure some of the support issues (Dana 44's from a scout)



The bending spindle is on the carriage, not the Suzuki. Even the little Suzuki axles seem plenty strong, even with this "100% offset" type of track. Designs that use automotive rims modified as drive sprockets put MUCH less stress on the vehicle spindle - but my design just came with too-small trailer axles on the carriage. It was a case of the designer being an engineer and trusting his numbers without thinking it all the way thru. 

Picture says it all - he ran axles (two spindles) rated for 2000lb trailer - so four spindles should carry 4000lbs right? Not at crazy wide/way offset loads like we have here.






Also included in the pic is my band-aid solution for the front/steering assemble - rollers to keep it supported on the inner side. In the back it will had a strut going to the axle itself to provide support there. I can do that in front too but it will take more work 

This will be when I don't use the Unatracs - which while super heavy and hard to steer are pretty durable and reliable. 

I'll have pics this weekend with my new "snow-cat body " installed, with tracks. I won't be going far from the road so if I REALLY screw up and break a track or something I could go get the 40" tall Boggers and run them at 1 or 2 psi - I am sure that would be enough for the packed trail to the Iditarod viewing spot, just a mile or two from the main road.










redsqwrl said:


> *The air locker topic:*
> 
> 
> 
> Would you be able to turn a locked, welded diff. (i think so)
> 
> Mike in WI
> Thanks for sharing. all things tracked seem to occupy my brain these last few years.



Yes - an airlocker would be cool, but I was running a ez-locker in back before, and now am "fozzy-locker'd" in back, with an ez (mini locker that replaces the spider gears) in front.
Fozzy locked is the very scary but so far proven method of welding in the valleys on the spider gear so that the axle can roll nearly a full revolution before binding/locking up. Toyota axles seem to survive this on rock-crawlers/low gears/40" tires. So far I like it, but a lincoln-locker or spool is likely a safer bet.

Regardless, I've run 35" tires on a lincoln-locked Samurai axle for thousands of miles with only tire noise/chirping as my biggest complaint. Given the slip of snow, and the 15"-tires size of a drive sprocket, locking will be fine for the gear and great for traction, IMHO.

Unatracs being tested by the Army, 1970-ish





Mine again






35 year-old plastic tracking (molded in in pieces linked by steel rods - made by a company called Fastrac about 1970-72) reinforced by rubber belting bolted to the edges)

Mattacks, to preclude confusion:


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## deepmud

Tops on, tracks are on - I'm a dummyand have put off the ram-assist steering again too long and have blown the high pressure line on my power steering ( Scout II box adapted to ZF/VW pump)  - it's  a know issue for me, as much from the rebuild-able fitting at the steering box as from the massssssive steering effort of the 5 foot long tracks (later models of Unatrac lifted the front and rear bogie off the ground about 4 inches - aids in climbing, eases steering effort).

Here it is with just the rear tracks - too dark for pics by the time I had the fronts on....


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## Melensdad

Awesome projects.

Are you _(did you already)_ beefing up the rear suspension to compensate for the added weight of the wooden enclosure on the rear end?


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## deepmud

Well - it's heavier then I would like, but maybe less than 200 pounds? It doesn't compress the springs appreciably. I have a fully custom suspension, using springs from a Jeep TJ, and a sort of wishbone suspension, a la Model T or Unimog - commonly called "one link" tho' if you count the panhard there are two links.  Very flexy, I ramp about 700  - means I can lift one tire about 3-4 feet up with 3 still on the ground.

I drove it around the block in "rear track drive" (think half track with no front wheel drive) but I don't think it would do well in deep snow like that - it can't even push my tires up a snowbank like this. I think maybe it needs grousers? This is a good question for you real snow-cat guys - how big a deal are the grousers? Is a tall (2"?) grouser much better than 1"? I'm thinking it would link the belting that was added to the edges of the tracks across the middle plus the added traction would be a bonus. They ride like crap anyway  - the roller bogies are running on the drive windows and on hard-pack they rattle the whole rig at slow speeds. 20mph is pretty smooth tho'.


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## deepmud

Tracks on all four, but with high pressure steering line killed making tight turns getting on the trailer.


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## deepmud

My rig on 2007, built to clear 45" tractor tires. They work pretty well in snow too.







out and about with the 39.5 Boggers on - also good in deep snow, at 2psi (in the tire).


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## Snowtrac Nome

deep grousers suck up horse power and vibrate more my st has grouser bars that aer about 3/4 of an inch they work just fine


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## deepmud

I took a look at your album - looks like your grousers are u-channel steel? like 3/4 by 1?


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## Snowtrac Nome

they are actualy a u channel tapreed down on both sides with a solid insert in the center i can out run a bv 206 in the deaper snow and on snowmachine traild the bv runs about a 2 inch lug and you can run about 30 mph on ice and when you hit snow it will just about shove you into the windshield and slow down to about 15mph instantly


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## deepmud

the BV slows down? due to power-eating of the big grousers?


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## Snowtrac Nome

yes


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