Direct hydraulic drive rotary mower deck.

[oughtsix]

My 19 year old JD F725 is slowly petering out on me (About 2 acres of my personal lawn twice a week only). It is on it's second engine and the deck has many welds on it. I just got through replacing all the spindals with aftermarket clone spindals. Every imaginable jointed part is wallowed out and repaired at least once.

I have been looking at ZTR's (Zero turn radius) mowers and anything in my price range seems to be some what lower quality than what I could build with my 20+ year old erector set (You know when they were all metal except for those plastic tires). So time to build my own ebay special!

I have picked up the rebuilt White Hydraulic wheel motors and a nice brand new dual variable displacement pump. I am too ashamed to admit to the motor I am planing on using.

I am having the hardest time visualizing how I am going to build the deck. My 54" JD deck does a lot of scalping on the small hills in my yard but I really don't want anything smaller as I don't enjoy spending that much time mowing. Some of the ideas I am considering:

A) Cut 3 x 24" circles out of 1/4" plate. Cut a couple of old car tires in half (around the circumference), put them over the 1/4" plates and call them a deck. Mount the 3 decks with 8 casters and make them articulating. Problem - The line of grass missed between the three decks.

B) Make three hinged articulating square decks, drive the center blade the opposite direction of the outside blades and overlap the blades. Problem - Hope they inter-mesh and don't chew each other up (Maybe use hinged (flail) blades in case they do come in contact?).

I figured either of these two articulating designs would be accomplished by having one hydraulic motor per blade. I see Surplus center has some .218 cu in and .371 cu in hydraulic motors rated up to 5000 rpm. I am thinking of directly mounting the blade to the motor shaft. Can anyone think of a problem with this approach? Another option would be to use lower speed motors with belts and pulleys but I would hate the extra complexity! In either case I was thinking of running the three hydraulic motors in series with their own dedicated drive pump.

Has anyone else put any thought into their own mower deck design? Any other thoughts?

 

[J_J]

Power-Trac does this with their hyd driven decks. One hyd motor to drive all three spindles. You put one blade forward of the back two just like a standard deck, that gives you the overlap. You could get away with side by side, but you would have to use a cogged belt and align the blades when installing the belts, so one blade is cutting inside the circle of the other blade. My Troybuilt mower does this.

You could also push or pull a Trail mower around. I have a Trail mower with 44 in cut driven by a 11 HP Honda. Used a single blade.