Logging Halftrack

[Dennis Cardy]

Not sure where to post this.

Got to watch this logging truck being restored at the the Simcoe County Museum last summer. It has the most complex track system I've ever seen.

Took me a while to figure out how it works.
Appears to use an inner rotating roller-track to support the load...as opposed to the standard fixed rollers.

https://youtu.be/RZx92HvK4go

Seems fine in the snow...guessing muddy conditions would soon grind it to a halt.

Was this ever used in military applications ?

[lynx42]

Yes and No. The vehicle is a LINN Linn tractors were used to haul freight beyond the ends of the rail lines on some Canadian power projects. A flexible traction system, independent of each other, with a central triangle-shaped rocker using two tear-dropped runner blocks suspended by axles, an independent roller chain was used to disperse the load through these rollers, it was patented in 1918. The feature being with constant ground following traction. When the concept of rural snow plowing became accepted around 1920, Linn was one of the pioneers, with a v-plow and adjusting leveling wing design that was unmatched until better pneumatic tires, four-wheel-drive trucks and better highways appeared in the mid-1930s.

A new concept of a single machine able to switch from truck to tractor with the push of a lever appeared in 1938, known as the C5 or later trademarked term "CATRUK", but management and war priorities limited its development and it was abandoned after World War II. This machine was built in a cab-over configuration, front wheel drive, and a hydraulically lowered dual-wheeled tag-axle that would push the tracks up off the ground. "HAFTRAK" is another Linn trademark.

John Belfield has restored a C5 which was used by the American forces in WWII. It is believed that some of these vehicles were used by the US Navy during WWII for the recovery of landing craft.

Corowa_08-08_fs.jpg

Regards Rick.

[Lang]

There are at least two Linn tractors in the Brisbane area. Note the electric start on the green one!

[Dennis Cardy]

Lang and Rick, thanks for that info. Had never seen one before.

Rick's explanation of how the system works was most helpful, and helps me understand how it all works, as the drive sprocket and front idler seem to be bolted to the frame. I see now the triangular bit is pivoted to keep track on the ground.

How do you like the track auto-tensioning system? That's some spring.

Will pass the photo's on to the restoration gang. They started with a rusty relic, and had very little to go on.

If you watch the 3 minute video, it has a close-up of the track in motion. It's quite a sight to see it all moving.

Dennis

[Nick Balmer]

Hello,

While I am uncertain if Lynn half-tracks were used by the military, in Russia during World War I many American half tracked vehicles were fitted with bodies similar to those going onto armoured cars of the period.

Other Bullock and Allis Chamber half-tracks were fitted with smaller field guns for service as early self propelled guns. Many of these vehicles went on to play very important roles in the civil wars fought in Russia between 1917 and 1922.

[Nick Balmer]

Here are some more.

I have been looking for plans of the basic Bullock chassis for several years as I would love to be able to scratch build one or more of these extraordinary Russian conversions.

[GJG]

Originally Posted by lynx42

Yes and No. The vehicle is a LINN Linn tractors were used to haul freight beyond the ends of the rail lines on some Canadian power projects. A flexible traction system, independent of each other, with a central triangle-shaped rocker using two tear-dropped runner blocks suspended by axles, an independent roller chain was used to disperse the load through these rollers, it was patented in 1918. The feature being with constant ground following traction. When the concept of rural snow plowing became accepted around 1920, Linn was one of the pioneers, with a v-plow and adjusting leveling wing design that was unmatched until better pneumatic tires, four-wheel-drive trucks and better highways appeared in the mid-1930s.

A new concept of a single machine able to switch from truck to tractor with the push of a lever appeared in 1938, known as the C5 or later trademarked term "CATRUK", but management and war priorities limited its development and it was abandoned after World War II. This machine was built in a cab-over configuration, front wheel drive, and a hydraulically lowered dual-wheeled tag-axle that would push the tracks up off the ground. "HAFTRAK" is another Linn trademark.

John Belfield has restored a C5 which was used by the American forces in WWII. It is believed that some of these vehicles were used by the US Navy during WWII for the recovery of landing craft.

Attachment 95726

Regards Rick.

Linn was one of the first customers of Lombard who made a "camper" halftrack for Linn. Very satisfied, Linn worked for Lombard as salesman demonstrating Lombard log hauler. He started his own company after patenting his track. The US Army was trying to develop a halftrack after WWI and, in 1936, they choose the Ford-Marmon-Herrington T-9 with it's front driven axle. But the US Navy did ordered some C-5 which was also front wheel drive; the transfer case could disconnect the tracks with the idle rear wheels down for faster speed on good roads (35 mph instead of 6 mph).
http://flinflonheritageproject.com/w...67/1038957.pdf