If any of you are ever in the market for some sort of shaft that you would like to see make out of carbon fiber, I highly recommend Precision Shaft Technologies in Clearwater, Florida. Their website is here: looky. Yesterday the UPS man delivered a custom driveshaft I had made for our 1/4 scale tractor pulling tractor here at school. I tell ya what, it is damn sweet. It is comprised of a carbon fiber section, aluminum u-joint on one end, and a steel u-joint on the hardened end. I asked them what it would be worth if I would have had to pay for it (they donated it since we're a non-profit organization + they'll get some superb advertising out of it) and they told me $600-$700. The attached pictures will show it off a little bit more.

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Excuse the shitty tires, those are just used for rolling it on pavement because the the hard surface is so hard on our good tires.

how much does it usualy cost... and how much does it weigh compared to the metal one?

-E

Ummm, see post above. ;)
They said this one would have been between $600 & $700. As for the weight difference, since this one has a big chunk of steel on it I couldn't compare it to any that we have laying around the shop. I would say that there is a substantial difference though because just by lifting around the carbon fiber end it is damn light. Plus they can build these things to handle some serious torque numbers so it's all good!!

I see you are using a Sauer Danfoss 15 series U-type hydrostat in there!!!!

I like the driveshaft though. Once you get that tractor fully built, you'll have to post pics.

That I'm unsure of but I'm assuming you're right. I don't know a whole lot about the hydrostat except it is made by Sauer Danfoss here in Ames. The 2 seniors who designed just about everything would know all about that, us younger folk just help out where we can. I will definitely post up pictures when it is completed and hopefully a few from the national competition which begins one week from yesterday in Moiline, IL.

Yeah, I think the model number starts off BDU-10..... or something like that.

wow listen to the farm boys do their thing LOL

Tom only if you knew the amount of engineering that goes into something like this, I bet you'd be amazed.

Erik you're right about the hydrostat, it is the Sauer 15-U. As for pictures from the competition, I'll post up a few and if anybody wants more let me know and I'll e-mail you some.

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I should probably mention that the competition was held last weekend and we placed 3rd overall in the pulling area of the competition and 7th in the overall competition.

If anybody has any questions or comments please feel free to post them up (unless it's something like Tom wrote). :bounce:

why does it stick so much over the front? is that all just weight to keep it down? also it looks like it is a similar size to most riding lawnmowers. Is that the size of it or did it even start out as one? Very intresting....

btw how much did she pull?

FULL PULL 300ft!!!

The reason it is so long is because of weight transfer, the longer it is the greater the lever arm achieved which allowed us a greater lifting force on the sled's pan. I believe our tractor with the hood on was within one inch is being too long (we have a set of rules to follow by that's about two inches thick). It is roughly the size of a garden tractor gone mad but it did not start out as a garden tractor. The closest things we have that resemble a garden tractor would be our differentials which are from a Cub Cadet garden tractor but we run 100% custom gears within the differentials. As for our pulling distances I can't remember for sure but overall we placed third in the pulling area of the competition. We pulled in 1000, 1250, 1500, and 1750 lb weight classes. Our placing in the pulling area is based more on consistency throughout the classes more so than pulling distance and we were always in the top 5 so that's how we ended up 3rd. Here's a good picture of the tractor with the hood off.....