In 2014 we purchased and began using a John Deere Gator with Camoplast tracks to handle the bulk of our ski trail grooming. It also pulls our trail mower through 22 miles of rough trails during the summer.
As a result of a couple major breakdowns involving the Camoplast tracks, we’ve learned to carefully monitor the tightness of the bolt/washer combination that secures the hub bearings and holds the entire track on the Gator axle. Every 50 hours we perform a safety check on the tightness of the 12 mm diameter hub bearing bolts that hold everything together. If we discover a bolt is starting to loosen up, we replace it. However, on two occasions the bolt itself snapped off - requiring a delicate welding operation to mount a nut on the bolt shaft so the bolt could be removed. This happened most recently just one week ago.
The Camoplast tracks that we use are realistically designed for recreational use. However, we demand a lot more of the tracks when pulling heavy grooming implements up hills, down hills, across hills, over bumps and ridges. Even though we’re using new bolts and washers when they need replacement, they still have difficulty withstanding the abuse.
After one of these bolts broke off a week ago, we called Camoplast in Canada and spoke with a very helpful engineering technician. He knew that ski trail groomers in Europe had greatly diminished their problems with bolt breakage through one specific modification of the setup: they substitute a much thicker washer. This makes a lot of sense. We’ve noticed all along that the original washers tend to deform (cup) within the first 100 hours of use - probably allowing the bolt to loosen, perhaps allowing too much play at a point where the mechanical forces are extreme.
So this past week, we tried finding a thicker heavy duty washer by calling Fastenal, and by scouring the internet, and by speaking with representatives from several big online companies that specialize in selling fasteners. Nobody could provide what we were looking for!
Then an AHA! moment. How about trying the machine shop located 3 miles from our trailhead?
CPH Enterprises Inc said “Of course! - WE CAN DO.” They took the original washer, recommended an improved fitment for the bolt, and later that day provided a bid for fabricating the washers we needed. We gave the go ahead, and actually had the opportunity to watch the machining in action.
They used a Waterjet Machine to cut the new thick heavy duty washers. After programming the specs, it cut the washers using water pressure of 50,000 PSI. I’ve never seen anything like it, truly amazing!
Think Global, shop Local.
The following pictures and video tell the story.
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