Hydraulic Or Mechanical Drive - Your Thoughts?

[Spudland_Dave]

Some of you may know I'm getting the parts & materials together to build myself a 3pt hitch power rake. I've been debating for 3 months now how to drive it...

A) Mechanical Drive - Do like all the other MFG's and go with the good ol fashioned PTO/Gearbox/Slip Clutches etc... Simple & Effective

B) Hydraulic Drive - Go with a similar setup to the Skid Steer rakes...I could either Chain Drive it like a Harley or I could Direct drive it...Motor Connected directly to the Drum. Benefit is I can fine tune the drum speed, etc..

With my Hydraulic sources, I figure both will cost me about the same in the end. Seriously, the ONLY thing holding me back from taking the hydraulic plunge was figuring out a nice resevoir for the oil...see...not only does it have to work, its gotta look good too....so I would need an elegant solution to that problem. With flow rates in the 13-15gpm range, I'm thinking I need some serious fluid capacity.

Looking for any input or ideas you guys may have on what you would do and why...

 

[kennyd]

My preference would be hydraulic I think...BUT using a motor that your tractor could drive directly so no extra reservoir would be necessary.

 

[groundcover]

If you go the hydro route(sounds like what the cool kids would do!) Don't forget to allow for the heat build up,pretty good GPM of oil there.

 

[Spudland_Dave]

My preference would be hydraulic I think...BUT using a motor that your tractor could drive directly so no extra reservoir would be necessary.

Thats the problem Kenny....Any motor powerful enough wont turn fast enough with the measley flow from my 3520.... once you get into the 13gpm ballpark, you can get all kinds of motors that will spin the rake with enough power/speed....
Unless you know of another motor I can use? Most of the motors I know will work (cause they're the ones used on the SS units) are in the 12.7 Cube displacement range....desired RPM is 250-300, force output is something like 4500 in-lbs....

When I said resevoir its because I was gonna mount an Auxillary hydraulic pump on the PTO and make a complete auxillary system...hence the need for the resevoir.

 

[bobodu]

Hydraulic motors take a huge amount of flow and generate a fair amount of heat,as has been mentioned. If you don't have the flow available...your pretty much out of luck without adding a bigger pump.You could do this off the PTO though.Were it me, I'd go with a belt final drive off the PTO. This would allow a measure of safety should you pick up a rock or large dog. Even Harley has gotten away from the chains,although they still haven't made the leap to the much better shaft drive like Honda did on the GoldWings 30 plus years ago....

 

[tlbuser]

Seriously, the ONLY thing holding me back from taking the hydraulic plunge was figuring out a nice resevoir for the oil...see...not only does it have to work, its gotta look good too....so I would need an elegant solution to that problem. With flow rates in the 13-15gpm range, I'm thinking I need some serious fluid capacity.

Looking for any input or ideas you guys may have on what you would do and why...

1) If you're building the frame from square tube, couldn't you increase the dimensions of the tube to get the volume needed for a reservoir?

2) Think round, reservoirs don't have to be square. A polished stainless tank mounted forward of the gear box......or between the rops uprights if using for other projects too.

3) Triangular, polished stainless mounted between the hitch arms

 

[Renze]

i dont know how much power youre going to need, but hydraulics are ineficient in general, and the hydaulic systems of most tractors can transfer about 20% of the engine power to oil pressure because of small pump used.

 

[Spudland_Dave]

1) If you're building the frame from square tube, couldn't you increase the dimensions of the tube to get the volume needed for a reservoir?

I thought about that, but I just cant get the volume...using 3" Square tubing gives me a capacity of 1.95 Gallons (Assuming 100% full) nowhere near to close enough if I go the 1 gallon for every 1 GPM of Pump...

2) Think round, reservoirs don't have to be square. A polished stainless tank mounted forward of the gear box......or between the rops uprights if using for other projects too.

3) Triangular, polished stainless mounted between the hitch arms

Both great ideas, BUT just think about the physical size of the oil I need....3 complete 5 gallon pails...Thats a frikkin BIGGG Resevoir... Unless I go with a much smaller resevoir... Maybe I gotta start a new topic over in the Hydraulic section...

 

[bobodu]

You wouldn't need the full fifteen gallons if you add a cooler.

 

[gordyy]

note BEER kegs pollished and clear coated always make things look cooler

a 16 gal keg polished would make a heck of a tank

and think of the kewl factor teenagers like kegs