Bush hogger!

[mindymogul]

No.... Get ya'll minds out of the gutter.

ANYWAYS!.... I picked this old thing out of a scrap pile I picked up and noticed it actually had some life left to it. Looks like its witnessed the Titanic going down then mowed half of Montana. My lil' GT5000s don't quite have enough "umph" to mow the fields so I thought I'd try and put some use to an old Cub Cadet deck and see how else I can kill myself! But I need some advice on people who may have actually done this because I do have something to live for. 4

Deck size is 58" w/ 3 18.5" blades. Weight is about 135lbs
Belt Drive gearbox is 1:1 w/ 7/8" In/Out shafts.
Pulleys are 4" w/ 5/8" shafts.
Inertial Rotation/Belt Friction Resistance Value: 72.4 Ft Lbs at maximum rotation.

Engine Options: Vanguard 18hp Horizontal (1992 model), Tecumseh OH130, Tecumseh OH110, Briggs 11hp Vertical, 9hp 212, or stock 212 w/ CVT.

My original idea was to convert everything to #420 chain drive so that the powerplant would be more universal with a quick sprocket change. But then the idea of belt drive would be nice because there's less change for binding, less need for lubrication, and the convenience of a belt is just a pulley turn away from installation.

Arguments: Vertical Shaft would require more fabrication but removes possible failure points (Gearbox), Horizontal Shaft would require less fabrication but clearance issues are a problem. (Gearbox input pulley to deck surface, Pulley to drive belt distance, Tensioner shroud to surrounding areas (If CVT is not an option). CC w/ pulley would be convenient and less costly but would burn up clutch w/ 3:1 ratio.

For the physics pro's out there... What would be the best bet?

 

[Brianator]

I see that and think it would make a great tow behind with the 10 horse Tec powering it via the gearbox, all fabrication (frame and motor plate) should be pretty straight forward. With a belt drive between the motor and gearbox you could make a frictional style clutch like what's used in lawn tractors and snowblowers plus if you could get your hands on a variator pulley you could have ultimate control over blade speed...

I'm not seeing the clearance issue you speak of but maybe I've just mapped out motor location differently than what you've envisioned?

 

[mindymogul]

The mounting plan was directly above the gearbox. My idea was a friction drive from a snowblower but the belt slippage would be way too much and I'd have to put on a jackshaft. The belt for the rear blades undermines the input shaft and even a 3" pulley doesn't have clearance, and ZERO clearance with the debris shield. The driveshaft that ran this is double u-joints on the yokes so can't use that. My idea was just make a plate or use an old CVT backplate to mount the engine off the gearbox studs, but I dont think that can handle the strain of weight and tortion. (Lightest engine I have is over 30lbs). Hence idea of CVT so it's fully remote control from the tow vehicle.

 

[Brianator]

You can get the "remote control" from a variator pulley, it essentially works the same as a CVTs driven pulley but need to be changed manually (push type lever with a spring and a locking mechanism). They're found on some Sears and MTD lawn tractors, look em up if you're not familiar with them.

With a frame under/around the deck and a "trailer tongue" to hook up to your GT there should be plenty of room ahead of the deck for the engine to sit and I'm sure it wouldn't be TOO difficult to couple and support an extension shaft from the gearbox towards the motor, no more clearance issues!

I thought about belt slippage too but then realized if a small, old, belt drive lawn tractor (like mine - 1969 MTD 7hp) can handle as much weight as I've thrown at it and never smoked a belt then a well designed system with a good strong spring on the frictional style belt clutch could surely handle what you'd be asking of it! Lol. I think WHAT belt/pulleys you use is what will be important here if you want to go that route, B series would be the way to go and if for some reason there was slippage you could always run a double pulley system (but I doubt it would come to that). Will the 10hp handle it? Probably, they are strong motors but it's great you have others options!

But hey I'm just throwing around ideas there! I was planning on building a (smaller than yours) tow behind using 3 push mowers and a 6.5hp Tec vertical shaft to cut my lawn quicker but then I finally came upon my dream tractor, a 1974ish Bolens G10 garden tractor so that plan has been kiboshed! Lol

 

[Kartorbust]

My thoughts would be if you can, ditch the RAGB and make an engine mount for a vertical shaft engine, then get an electro-magnetic clutch. That way the engine will still run while the blades are disengaged. You could if you are feeling up to the task, mount it on the dash board of the tractor you'll use to pull it with, then route the wiring to the draw bar and put a quick disconnect connector there.

 

[anickode]

Friction drive will be a no-go. They're designed to transmit a fraction of a horsepower to scoot a snowblower along, and nothing more.

Belt drive will be perfectly fine. Does that gearbox speed up or slow down the drive? Most shaft driven mowers are designed to run off either a 1000 rpm or 540 rpm pro shaft, so running a 3 or 6 to 1 reduction into an increased box would be a waste of power. I would certainly think making it vertical shaft drive and eliminating the gearbox would be better from a mechanical standpoint.

Belt drive is definitely what you want IMO. It will handle the torque just fine, and if you hit a blade-stopping obstacle, it's far less likely to send parts flying, and will absorb the shock better.

I've been wanting to get a second deck (smaller than the 60" belly mount) for my tractor and convert it into a wing mower driven off the hydraulic PTO. 9 foot mowing swath baby!

 

[Brianator]

By frictional I did mean belt, lawn tractors that are belt drive use a frictional belt.

A 9 foot clearing path sounds great man, make it happen! Lol

 

[mindymogul]

I decided that I'm going with #35 chain because I already have the sprockets, and the fact that it has the minimum tensile strength for what I wanna do. My plan was to run a 43x1/2" belt off a pulley CC of the RAGB (Simplicity and I have it mocked up already so might as well weld everything). Plus if there's something for a jam or break it doesn't full stop the motor. At worse it'll just burn up the clutch. I also had someone make up a lil' RPM gauge that'll read off the external drum of the CC that if it decelerates almost instantaneously it'll kill the engine before damaging it. And for engine I'm going with the OH110. Has 12v start, charge coil that works, and has the most recent rebuild. The spindles for the blades are actually 3/4" shafts so everything is going together way too perfectly. Something's gonna screw up right when I'm near completion. (Chain breaks and I lose my leg most likely). I have a 26mm china carb kit with the correct adapter so choke will be auto, and it has an auto gov so everything is gonna be cable-ess...thing...yeah. Oddly enough with some minor mods that deck will fit on an old MTD 990 I have but why would I do the simple thing and just rebuild the engine on that? That makes too much sense. (I would slap a 760 on it but the local 3 HF's haven't had them in stock for a couple months now and I now live a budget life).

 

[Brianator]

Sounds like a good plan! The 990 is a horizontal shaft GT isn't it? Why not slap the motor in it, add the deck and go nuts?! Lol. I have the 990s little brother, a '69 MTD 700, still can't find a cutting deck for it after a couple years....

 

[anickode]

By frictional I did mean belt, lawn tractors that are belt drive use a frictional belt.

A 9 foot clearing path sounds great man, make it happen! Lol

Gotcha. You said snowblower and it made me cringe. There are a few of the wee baby riding mowers that used friction disc clutches on the drives as well, so that's where I misunderstood.

I'm afraid my project budget is rather thin right now, between fixing up my barns and knowing I'll be purchasing a new vehicle sometime within the next 12 months. I have been laying out a new kart frame though... Might be a while before it rolls, but hopefully I can start welding soon.

 

[Brianator]

There are a few of the wee baby riding mowers that used friction disc clutches on the drives as well

No kidding! I'm no stranger to all sorts of equipment and have yet to come across that, sounds pretty interesting. Do you happen to know a model offhand? I'd like to research it just because that kind of junk fascinates me!

I have a bunch of stuff on the back burner because of other things that need to get done so I know where you're coming from, all in due time right!?

 

[mindymogul]

I'm supposed to be stripping out an old house trailer on the property and make it look like it never existed from when my parents owned this place by the end of this month or face a $9500 fine and possible jail sentence for violating state codes. Alcyhol and bad relationships magically made that project dissapear from my vision. Also pointless projects that'll never be finished. Spent almost 4 hours wiring one of the twins (GT5000) only to pull it all apart again because I didn't like the flickering and the led pods made the the hood look stupid. Then proceeded to get the tire off the bike because that's actually due for inspection and isn't a major crime that I should stop everything else for and get done. Priorities people! They don't matter as long as pointless things come first!

 

[anickode]

No kidding! I'm no stranger to all sorts of equipment and have yet to come across that, sounds pretty interesting. Do you happen to know a model offhand? I'd like to research it just because that kind of junk fascinates me!

Offhand, weed eater, a few of the snappers, and I think the little Ingersoll one (not ingersooll rand) were like that. Probably more, since most are made by a handful of companies.