3# PROSTOCK BUILDUP

PROJECT UPDATE---HERE ARE SOME PICS OF AN EARLY FITUP OF THE TRACTOR.

I DECIDED THAT I WANTED TO BE AS LIGHT AS POSSIBLE. THIS PRESENTS SEVERAL CHALLENGES IN THE PLANNING. THIN-WALL C-CHANNEL IS BEING USED, AS OPPOSSED TO THE SOMEWHAT STANDARD BOX TUBING. THE MATERIAL IS 1 5/8 INCH WIDE, AND 7/8 INCH DEEP. THE BOTTOM IS 1/8 THICK AND THE SIDES ARE 3/32 INCH. NEXT , I DECIDED ON A VERY LIGHT HOOD ASSEMBLY. I AM USING A HESTON HOOD, THAT IS PLASTIC. I WILL BE USING BEARINGS INSTEAD OF BUSHINGS. BUSHINGS ARE LIGHTER, BUT I DESIRE THE TRUENESS AND LOW FRICTION OF BALL BEARINGS. ALL MY SHAFTS ARE TO BE ALUMINUM, INSTEAD OF STEEL. THIS INCLUDES THE REAR AXLE. THE CLASS DOESN'T PULL HEAVY WEIGHT, SO THERE WILL BE NO PROBLEM WITH TEARING THINGS UP. I WILL ALSO BE USING PLASTIC GEARS, EXCEPT FOR THE FINAL GEAR, TO LOSE MORE WEIGHT. NYLON GEARS ALSO ARE SELF LUBRICATING AND LESS SUSSEPTIBLE TO WEAR. THE FACTORY PLASTIC RIMS WILL BE USED WITH HUBS, AND BENNETT TIRES WILL BE INSTALLED. THEY TEND TO BE LIGHTER THAN THE HI-LIFE PULLERS.

THE NEXT ITEM TO CONSIDER IS GEAR RATIOS. THERE IS THE SLOW AND STEADY MINDSET (170-300:1 RATIO) AS WELL AS THE FAST AND FURIOUS WAY OF THINKING ( UNDER 150:1). I AM PARTIAL TO THE LATTER. THIS PROJECT IS BEING GEARED AT 100:1 REDUCTION. I WILL BE USING A 72T ALUMINUM FINAL GEAR, A 54T PLASTIC MIDDLE GEAR, AND 52T PLASTIC HEAD GEAR. THE PINION GEARS WILL BE 12T, AND THE CLUTCH GEAR IS 14T. BUT, BY CHANGING MY HEAD GEAR AND CLUTCH GEAR, I CAN ADJUST ALL THE WAY OUT TO 190:1 RATIO IF NEEDED FOR A PARTICULAR SITUATION.

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