Woods Finish Mower Issue

[chim]

I've seen frequent comments regarding using RFM's set lower in the front. I always use the same spacers on all four gauge wheels. Apparently level is acceptable by the manufacturer or it wouldn't be the first of two choices. One would assume that level wouldn't be listed if it matters.

From the LandPride O&M:

6. Measure clearance from the blade cutting edge to the
ground at the front and rear of the mower. These two
measurements should be equal or the blades at the
front should not be more than 1/2" (13 mm) lower
than the blade at the rear. The rear blade should not
be lower than the front blade.

I still believe the OP's results are from cutting grass that's too high. I've had similar results. The blade is not slipping and the raggedy grass is the width of the tractor tire - not the blade length. When the grass is too long and gets pressed down, the blades can't pull it up straight to be cut the same height as the uncompressed grass next to it. Look at the OP's picture "KIMG0711(1).JPG" where the cut grass is almost touching the bottom edge of the deck.

The only place the cut grass is taller than the bottom of the deck matches the path of the rear tractor tire. Next - and I'm guessing here - the reason the condition shows up on the right side is due to the deck being right-side discharge and the right blade lost a lot of its vacuum strength because it's being choked with all the clippings from the other blades.

The optimum PTO speed for my decks varies according to conditions. There are times during the mowing season when the grass is tougher, or juicier, or drier, or less dense, or thicker. Most of the time something around 400-ish PTO RPM's is good. Adjustments to both tractor and PTO speeds make a difference since the grass is a living plant adjusting to different weather conditions.

Marking belts and pulleys is an unnecessary exercise. Unless the belts have cogs that lock into matching parts in the pulleys (like chains and sprockets) they will definitely not stay aligned.

 

[dieselscout80]

I think it would be great to hear @dadohead thoughts on this as he has a lot of great experience in this area.

https://www.tractorbynet.com/forums/threads/hybrid-rotary-cutter-proof-of-concept.587997/

 

[zzvyb6]

I'll bet the blade retention bolts have bottomed out in the spindles, leaving the blades 'sorta tight' but not tight enough to cut heavy grass. This was a problem for me with the mulching blades that are slightly thinner than the originals. The new blades usually come with washers to take up the slop. Or, just use shorter bolts.

 

[Halftrack]

I was hoping the OP would respond before I started down this road, but here I go in hopes this benefits someone in the future.

Looking at photo #713 from post #1. I think it is clear that the center blade is cutting at least a half inch shorter than the right blade and shorter than the left. OP needs to raise the deck and compare the area where the blades "swipe" each other. Swipe should be 1/8 inch or less. If more, you've got spindle alignment issues.

Referring to OP's post # 6, he measures front and back blade cut height. WOW. The center blade is clearly lower than outside blades. REASONS: deck warped during tall grass episode, spindle slipping from original position, spindle housing bent or shifted on deck.

Additional blade height issue: the blades cutting higher in front than rear are going to leave a jagged cut due to less suction at rear and blade blowing grass down.

Where to start: after checking blade swipe issues, and correcting, if possible, lets start over leveling the deck. Take the caster wheels off, leaving the mounts on. Set the deck down on flat concrete and compare blade height of 3 blades. If insufficient clearance, put a 2x4 under each corner. If blade height is within your tolerance, measure height from floor to bottom of caster mounts. I think you'll find 4 different measurements. Allowing for the front of the deck to be 1/4 inch lower than the rear, stack your bushings/washers to give you your desired mowing height.

Did I miss anything? Questions? GOOD LUCK!!!

 

[chim]

I'm not sure that a "reasonably flat driveway" provides a very accurate base from which to measure. The differing measurements the OP gave could be due to variations in the driveway, bent spindles or a twisted / bent deck. Although it still wouldn't be perfect, parking the deck on a sheet of plywood would be better. The measurements given indicate the left blade is canted backward and the two other blades are canted forward. Maybe they are. Maybe not.

Since it's a three blade deck, and the spindles are not in a straight line left to right, The old "adjust the deck to cut lower in the front" approach would ensure that the blades cut to slightly different heights because the center blade is forward of the other two. Without accurate measurements of how out of line the spindles are it's a mystery just how much that would be.

 

[BrooksAGParts]

Turn your blades over and thry mowing again, the pictures show the blades mounted upside down and you are cutting on the backside of the blades!

 

[lman]

Turn your blades over and thry mowing again, the pictures show the blades mounted upside down and you are cutting on the backside of the blades!

Maybe I'm mixed up but that's not what I'm seeing. Did you look at post #21?

 

[alpha&omega]

Thanks, Leonz, if I recall, I believe the cup washers were pretty flat last time I switched blades and likely need to be replaced. When I installed the blades, I used the spindle lock wrench and a block of wood on top of the deck to keep things from rotating. Used a breaker bar with a pipe for more torque to install; didn't use a torque wrench or blue Loctite. I'll see about getting some of these parts ordered and getting a big torque wrench and Loctite.

Even still, if the blade is slipping on the spindle, how would that cause the mower to miss grass on only half of the blade and not the entire width of the blade? I'm not saying it's not slipping, I'm just trying to understand how slipping would cause it to only miss grass on one side of the blade.

Read through the posts @chim and @Halftrack took the time to write-up. These are about the most accurate descriptions I have seen yet.
I own several woods mowers and the information they posted is where you need to start.
Once you get everything figured out with the correct blade and deck level, you will need to take into account cutting height for that type of grass. I say this because it is going to cause issues with your RH discharge deck. You will need to mow that area twice if you want an even cut down to the level you are hoping to have.

The reason being is that the grass is stronger the closer it gets to the roots. An easy way to think about it is the strength of a tree limb vs. the trunk. When grass and weeds are tall, that upper portion of the blades and flowers are all new growth. It’s softer and easier to cut. Whereas the shorter grass, which has been cut multiple times over the years has developed rigidity. Not only from mowing, but also from being walked on, driven over, watered/rain/snowfall, frost/thawing…etc. What this does at the molecular level is cause a stronger crown (or base).
I say this because people think that when I cut tall stuff down from 20” to 10” it cuts great. That’s because it’s easier for it to cut and normally your deck is a little higher. However, that same cut becomes exponentially more difficult the further you lower the deck. The uneven ground, unlevel deck, warped blades, flattened washers, will also be more noticeable. Additionally, the lower you mow, the more likely it is you will see issues arise from things like; blade flattening caused by the weight of the wheels/deck, and depending on the speed you are traveling, the grass may not have time to stand back up (even with hi-lift blades).

You also mentioned using a big pipe for more torque. This is not necessarily a good practice when tightening down bolts/nuts. The torque specs are set for a reason and you may be doing more harm than you realize. While using a pipe is great leverage for loosening stubborn fasteners, it’s not optimal for torquing. You may inadvertently be the cause of your washers flattening, by over torquing the hardware.

I realize you have taken this to other mechanics, however, if they missed the items laid out by myself and the aforementioned posts, they easily could have looked over something simple. I hope this post does not come off brash, as it is common given the way I explain things. There is no tone assigned to the words in my message. I and the others wish you the best in correcting this issue. Please keep us updated with your findings, as it may help someone else in the future with the same or a similar issue. Cheers!