Can I use my 5ft finish mower minus one blade

[Bill_C]

I didn't use the same words, but that's exactly what I meant. Kinetic energy from the rapidly spinning and properly balanced blade stands the vertical spindle straight up - just like a kid's spinning top. That thrust relieves all but contact pressure from the bearings. Remove the blade, and you remove the kinetic source that commands the upright position. At that point the idler spring tension causes the belt to pull the spindle off vertical. Bearing wear ensues.

//greg//

Nope, not so!!!

I've had typical mower spindles apart. I've designed chain and pulley tensioners that spin far faster with heavier load.

The thrust loads from running the mower in the field are far greater than any load from the belt alone.

 

[RickB]

I didn't use the same words, but that's exactly what I meant. Kinetic energy from the rapidly spinning and properly balanced blade stands the vertical spindle straight up - just like a kid's spinning top. That thrust relieves all but contact pressure from the bearings. Remove the blade, and you remove the kinetic source that commands the upright position. At that point the idler spring tension causes the belt to pull the spindle off vertical. Bearing wear ensues.

//greg//

I have no idea what you meant. I can only read what you post, and that was incorrect as it relates to whether or not a blade is installed on a finish mower spindle.

 

[greg_g]

No problem guys, it's not your grass that needs cuttin' - or your mower that's being used. If Pooh can get his RC fired up, this disagreement is purely incidental. You operate your finish mowers your way, I'll operate mine my way.

//greg//

 

[Pooh_Bear]

I think I have rendered the entire discussion irrelevant.
I put 3 new blades on the finish mower a few days ago.
I just came in from mowing some of the worst of it.
I used the 3 point lift to hold the mower off the ground a few inches.
And then I just took narrow cuts. Sometimes very narrow cuts.
A couple of places the cut was only as wide as the rear tractor tire.
The grass in those places was at least 2 feet tall.
The tractor grunted a little but made it thru it.
If it will cut that like that then I can cut the rest of the yard.
In a day or so I'll go back over the whole thing again normally.

The grass is dry to the touch but it's full of water.
It's like mowing cole slaw out there.
Wish I could count on a few more days of dry weather.

Thanks.

Pooh Bear

 

[greg_g]

Good on'ya Pooh. You must really dislike that RC - to go through that kind of aggravation with a finish mower.

//greg//

 

[RickB]

Good on'ya Pooh. You must really dislike that RC - to go through that kind of aggravation with a finish mower.

//greg//

Amen to that.

 

[RobJ]

No problem guys, it's not your grass that needs cuttin' - or your mower that's being used. If Pooh can get his RC fired up, this disagreement is purely incidental. You operate your finish mowers your way, I'll operate mine my way.

//greg//

But it's a lot of fun Greg!

My FM has 7 idler pulleys on it, 3 just happen to have a blade attached. Remove a blade and it's just another idler, just the belt making another turn. I'll try it someday. Or you try it some day. 15 seconds and an impact and I'm down to 2 blades...next weekend.

If your mower has a gearbox, it probably has one, maybe 2 idler pulleys.

 

[greg_g]

My FM has 7 idler pulleys on it, 3 just happen to have a blade attached.

We have a terminology problem here. An idler pulley doesn't drive anything. As shown, you have three idler pulleys; only one of which is directly tensioned. So let's count. There are 7 pulleys visible - total. Three verticals and four horizontals. The verticals include the drive pulley (the massive one) and two idlers. Those idlers are fixed, and therefore do not exert tension. They just change belt direction from vertical to horizontal. Of the remaining four, three are driven pulleys (blade spindles). The fourth is an idler, almost certainly tensioned by that big honkin' spring in the foreground.

Remove one blade, and the belt tension from that spring will move the associate spindle off vertical. Bearing wear ensues until a spinning blade forces the spindle back to full vertical.

//greg//

 

[RobJ]

Remove one blade, and the belt tension from that spring will move the associate spindle off vertical. Bearing wear ensues until a spinning blade forces the spindle back to full vertical.

//greg//

OK we'll solve this, you are using the "off vertical". The spindle has 2 bearings and the belt is pulling one way and the blade another. The bearing on a "normal" idler is centered in the middle of the V groove, I get that. First if this was the case any "wear" would be so small. But using the "vertical balance" thing you are assumming that the belt is pulling one way, and the blade is pulling another. The blade is NOT because nothing is pulling on it. If the belt is pulling to the left, then the blade/grass load must be pulling to the right to balance it out. It's not. IF anything the load is pulling the blade to the front where it first touches the uncut grass. Now if you have an excuse for this, then what about the blade on the left side of the mower. The belt is pulling it the other way. Then consider the blade in the middle!! WTH!!??!! And all the blades turn the same direction. The ONLY kicker is on the right discharge RM360, the left blade has a smaller pulley, I think you can figure that one out. It turns faster.

BTW, my first comment said that removing a blade would not cause any additional vibration, not sure how we got off on wear.

Rob

 

[J_J]

The hub is just spinning with no load, acting as a second idler pulley. Should not have any vibration, unless some is caused by the other blades. You will probably have more rpm, and less load. Sharp blades would help even more.