Mower Blade Orientation

[tsimpson]

I have a 129 with the 44 inch 3 blade deck I usually drop the deck twice a year and sharpen the blades. I've never paid much attention to the orientation of the blades when I re-mount them. No matter how you mount then they can't hit the other blades but the cut seems to have a high spot at times and I'm wondering if the blade orientation has some effect on the cut. I checked the deck manual and there's nothing there. Does anyone have any ideas about this ?

 

[RayF]

There is no way to "time/orient" the blades on your deck. The pulleys allow for belt-slippage should you hit something solid... this will stop that blade, and you will smoke the belt, instead of stopping all 3 blades.
Do you have genuine Cub blades? I have Oregon repros (purchased/installed in 2006) on my deck, and one side leaves a 1/2" strip of uncut grass... so I have to overlap my passes 1/3rd. I suspect the blades are slightly shorter than the OEM Cub blades. I was hoping to wear these out soon... and replace with Cub Blades.

 

[snicklas]

Blade orientation doesn't matter on any IH Deck, except the 2 blade timed deck that was used with the original.

For your issues, I would make sure they are all put on in the correct direction (they can be put on "upside down", don't ask how I know this). I would also make sure you have the correct, and same stack up, in the same order. on each spindle. I haven't pulled the blades yet this season, so this is memory from last year, on my 44 I think the stack up goes like this: (with the deck "upside down" (pulleys on the ground)

On each spindle:
The "cup" that goes on the shaft, which the cup portion facing the deck shell. You'll understand exactly what I am describing when you see it.
The blade
The big washer
The blade retaining nut

I've also seen
cup
washer
blade
washer
nut

The big thing is, make sure each spindle is stacked the same way. If you have it stacked, for example

washer blade washer
blade washer blade
nut nut nut

Then you cut is going to look like this:

________--------________

 

[RayF]

washer blade washer
blade washer blade
nut nut nut

washer blade washer.. everything falls off...
blade washer blade... would cut really good IF everything didn't fall off....
nut nut nut... kinda overkill for not having to hold anything on....

JK...
(yes, I see the forum has removed how you formatted it to read as a list and not across... but that's not how it shows up in my browser.... lol!)

 

[mgwin]

Yes, Oregon blades do not last.
I put a set on my SCAG, and they wore more in two years than the factory blades did in ten! That's the last set I will ever buy.

 

[kmcconaughey]

For the 44" and 50" decks (three like sized blades) when the deck is upside down, the assembly order is Friction Disc (or Friction Washer), Blade, Washer, Jam Nut.

For the older 38", 42" and 48" three blade decks with the smaller outside blades, when the deck is upside down, the assembly order is Friction Washer (or friction Disc), Blade, Jam Nut.

 

[dfrisk]

On the 38, 44, and 50 inch decks, when the blade tips wear back and numerous sharpenings round off the outer end of the cutting surface those decks will leave an unmowed strip on tight turns. New blades with sharp corners is the only cure. You can stretch out a couple more years of mowing by only turning on the Headlands, or the 3-4 outer rounds I always mow around the outside to turn on. I resurrected a very well worn 129 to be my primary mowing tractor between about 1990 to 2006. The 44 inch deck had used blades when I bought it and still had the same blades when I sold it. It mowed over 2 acres a week except for maybe a year or two.

 

[rengasser]

If you are getting an uneven cut with the blades correctly installed and the deck leveled, here are two tips. Set your mower height with the cam stop for the lift. Then set the mower gauge wheels to just clear the ground. This will eliminate the scallops in the lawn if the mower gauge wheels are trying to carry the deck. The second thing is rust can build up between the mower deck shell and the flat plate above it that the spindles go through. This can cause the spindles to tilt. The blades will not align and you get an uneven cut. This can be corrected by removing the plate and cleaning up the mating area. This applies to the 44” and 50” deck.

 

[tsimpson]

Thanks very much for the information. I don't know if these are factory blades they don't look exactly like the FESM 2828 image but they are pretty well made and the rotation is secure and square with the deck I'm going to check the deck the next time I pull it. I don't recall seeing the friction disk on any of the blades mounting surfaces. Are they a grit, fiber dick or a serrated metal washer?

 

[kharvey]

Fiber type disk. I made replacements out of a piece of formica countertop laminate.

 

[PACub100]

This may be something to look at - are you sure one of your blades isn't slightly bowed / bent at any given point along the length?