Cadtrac Plans

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tky

B

bpercival@shaw.ca

23 hp engine with a double pump hooked to it. 12 gallon and 8 gallon. the 12 gallon is for wheel drive motors only. the 8 gallon is for the steering and bucket controls. we eliminated the flow divider by using the double pump. i also hooked the 8 gallon line to a sun priority flow valve with the steering getting priority over the bucket controls. increased the hydraulic tank capacity to 12 gallons. my hydraulic engineer calculated that the original plan would have a top speed of about 2mph, not the 3.5mph that is stated. the change that i made will give the wheels more power and a top end of about 4.5mph.

As I mentioned in an earlier posting I am using a Kawasaki 22 hp water cooled engine a larger pump, flow dividers, and hydraulic tank. When I'm finished I expect a somewhat faster ground speed of about 5 mph. The oil flow to the bucket cylinders is regulated to a volume and pressure similar to the original plans to avoid jerky movements and pressures beyond the capacity of the arms and bucket.

The specified tank (made from an 8" tube) doesn't match with the text in the instructions. The text calls for a minimum of a 7 gallon usable capacity. If you calculate the capacity of the tube tank it is slightly less than 7 gallons without any room for expansion due to heat or an air cushion to allow for possible oil foaming during high volume circulation. Since this is a hobby I have decided to locate the parts individually rather than purchase the kits. So far I've found everything either locally (or on the Internet) for less than half the kit price. The trade off is that the construction time has been increased substantially from the 50 hours estimated by the designer. So far the project has been a blast. The next big decision is what to do with the thing once I'm finished.

tky

B

bpercival@shaw.ca

B

What else have you built. We built the digger and love it. We are going to build this cadtrac or build a bobcat type of machine from scratch.
Any chance you would trade a copy of the cadtrac plans for the digger plans or for cash?

tky

B

Jon

thanks

This arrangement limits adding a digger attachment without substantial changes to the mounting system.

Other changes: i designed a quick hitch for the bucket so that I can change implements easily. ROPS using 2 1/2 square tube in the loader posts with a "roof" covering the seat. I also routed the return from the steering through a heatexchanger/cooler mounted on the tank. The gas tank is mounted between the operator's feet.

When i get a chance, I'll post some photo's if anyone is interested ....

• Shop photos

tky

B

I just ordered the Cadtrac plans yesterday! Half the reason I plunked down the $200 was to see how the hydrostatic drive works. I'm a little bit concerned about how small it is and I may try to scale it up a bit, don't know yet. I'd also like to build a clamshell bucket for it.

So far I plan on scrounging most of the steel and buying a few of the Metkit parts that will be harder to make or find. What are you going to use for an engine? I've thinking about a liquid cooled motorcycle engine.

Good luck with your project.

Bob

Remove the "nospam" from my e-mail address to reply via e-mail.

tky

B

My main concerns are top speed and how steep of a hill it can transverse(plan on using it as a general purpose mule and highly manuverable bushhog with a front mounted hydraulic deck.

Thanks for any comments.

tom

tky

I have the same sort of unanswered questions as you, but I went ahead and ordered the plans last Friday. When I called, the only person there was a lady who didn't have any answers. I want to learn about hydraulics, which is part of the reason that I ordered the plans. I think I will be modifiying the tractor and just using John's plans as general guidelines.

I may change my mind as I get into the project and build it pretty much per the plans though.

I'm pretty sure that we can increase the engine HP and tractor speed, but we have to consider the whole system. If we upgrade one component, we probably have to review everything else, and most likely upgrade everything else. ($$$) I've noticed that some commercial small loaders have two pumps on a common shaft, a variable displacement pump for the wheel drive and a positive displacement pump for the implements.

I'm thinking about a liquid cooled motorcycle engine at the moment. This is going to be fun.

Regards,

Bob

Remove the "nospam" from my e-mail address to reply via e-mail.

Well, I also went ahead and ordered the plans (yesterday). I got some answers to my questions:
Braking - just the hydraulic wheel motors and there is a simple bar that jams against one wheels tire lug for a parking brake. I'm thinking about wheel motors with brakes but they are expensive.
Split Hyd. - Wheel drive and loader are separate. Loader and extra Hyd for digger or other implement are same so you can't use loader and digger at the same time (now that would be a sight..)
Power/speed - flow divider is limited to 8 gpm/circuit so if the motor and pump are upsized the flow divider will have to be also. I had also thought about a 2-stage pump for the wheel drive ... perhaps I'll keep on thinking..

I talked to the guy at CadPlans.com and he says he's been selling the Cadtrac plans for 6 years now, and there a lot of finished tractors out there. I didn't ask him for any individual references though. He says a lot of his customers modify them for their specific purposes.

Bob

I'm right on the verge of buying the plans andstarting and just have a few questions that I'm trying to get answered, such as:

Is there any positive braking provided? parking brake? Can I up the horsepower and Hyd pump and get more speed or will I have to re spec the flow dividers etc. Are Split Hydraulics designed in so that I can operate loader/digger while moving ... Does he have any ideas about providing ROPS.. and so on

In any case, I hope to have one in operation by the late summer Thanks for your comment and I'll keep you posted.

Also if anyone has any feedback on how to speed these creatures up and what inclination they can transverse whithout turning over. I plan on using it as a general purpose mule and highly manuverable bush hog(front mount hydraulic drive - obviously I've got to bump up the GPM).

Sorry if this is a repost by my original didn't seem to get through.

tky

b

I will be using the tractor to move a camper, a boat and a utility trailer around in a very confined spot, so therfore I would omit the
loader portion of the project.

I also have a problem paying 200$ for the plans with no idea of how it will preform, not to mention the 6400$ the complete parts kit will cost. (www.metkit.com)

If anyone would have a comment, idea, or other similar option please let me know.

Thanks