Deck Design ??

[RayMcD]

Best design is one single blade. End of message. His and her push mowers........

Yes Sir, at least once a year and logged in the history, I myself find this little need as it is typically very clean

 

[RayMcD]

Once again this is a MULCHING deck set of baffles
Thus the grass is running in a clockwise direction inside all of the blade circles
So as first posted at the intersections of the cutting circles the left side clippings are going down and the right side clippings are going up
Thus the clippings stop moving for a second because the air flow is going in opposite directions so just like in a flowing stream the clippings loose speed and in your case stick to the deck.
Now I personally would leave them there as they do not hinder the deck air flow, in fact they enhanse it .
They build up because there is too much volume of clippings or you are using the wrong blades .
That is is nothing more & nothing less
On my commercial customers who drop their mowers off on Friday for a weekend blade sharpen & deck clean, they all have build ups there and I leave it alone
The build up of grass clippings should not be a problem
Whrong blades, mowing too fast or cutting off too much grass is the problem
The deck build up is not a problem anywhere other than in your mind .

Bert, I agree 100% the issue is caused by airflow (actually lack of it) a the intersection where the blades cross. As to the type blades I run. 112111-01 OEM which are slightly offset and the XHT equivalent which are actually flat with a longer cutting area and a similar turned up trailing wing. I normally have my deck set at 2.5", run full throttle as recommended and poke around easy so not to tear up the lawn, gov's never get to open up.
I also agree that these small areas of buildup pose little trouble, I do clean often, repaint and coat with oil to prevent rust but will continue to look for a long term solution to keep it clean. Cheers, Ray

 

[bertsmobile1]

The deck does not rust under the build ups which you have probably noticed.
The biological oxygen demand of the bacteria decomposing the grass clippings is greater than the entropy for the iron to convert to rust
Decks rust out from the outside in not the onside out.
If you are running 112111-01 blades then there is you problem.
They are throwing / bagging blades not the mulching blades The Bob-Cat mulching blades that go with that deck are a toothed style with a wavy leading edge so they create an updraught at the cutting tip and a downdraft around the centre of the blade to pull the clippings down & deposit them back into the lawn.
Down side ia AFAIK they are unique to Bob-Cat and only available from a Bob-Cat dealer $$$$ with no aftermarket blades available .

 

[StarTech]

The deck does not rust under the build ups which you have probably noticed.
The biological oxygen demand of the bacteria decomposing the grass clippings is greater than the entropy for the iron to convert to rust
Decks rust out from the outside in not the onside out.

I have to disagree. I have seen massive rust areas on decks here on the cutting side and painted side had little rust. Enough that it comes off in huge flakes. I actually had to rebuild one deck last that an idler pulley mount complete through from the inside. Just depends on the environment the deck is in. Mositure is one of the main enemies.

 

[bertsmobile1]

So what ratio do you see of decks rusting through from the outside comparred to from the inside ?
What causes a lot of rusting is perpetually scraping the deck or using wash out ports badly .
So I should have been more prescriptive
Usually decks rust out from the top down because he grass on the top is loose packed and will adsorb a lot of water and remain wet thus promoting rust
If the deck is not washed underneath thenthe bacteria decomposing the grass will adsorb all of the available oxygen then go anerobic
So the only area that can rust is the very edge of the packed in clippings .
And top down to bottom up would be about 50:1 for this little black duck .

 

[slomo]

Winter off season, slather the under deck with used oil. Great way to recycle used oil.

 

[RayMcD]

So what ratio do you see of decks rusting through from the outside comparred to from the inside ?
What causes a lot of rusting is perpetually scraping the deck or using wash out ports badly .
So I should have been more prescriptive
Usually decks rust out from the top down because he grass on the top is loose packed and will adsorb a lot of water and remain wet thus promoting rust
If the deck is not washed underneath thenthe bacteria decomposing the grass will adsorb all of the available oxygen then go anerobic
So the only area that can rust is the very edge of the packed in clippings .
And top down to bottom up would be about 50:1 for this little black duck .

Bert, I agree that with on water or oxygen there is no rust. Your heart is in the right place Sir, thanks, Ray

 

[MParr]

Try different blades on your mower before getting in too deep. The part number for your blade indicates that they are flat notched high lifts. Rotary make a 1/4” offset blade with a rolled lift. I would definitely try those before spending a lot of time and money. Gravely uses the same style blade and they perform very well. The Rotary part number is #3400.

Rotary # 3400 Standard Lift Lawn Mower Blade For 48

www.texaslawnmowerparts.com

 

[bertsmobile1]

If you search for Bob Cat mullching kit you will bring up an image showing the baddles the Op has shown and some way blades rather like the Husqvarna mulching blade except the flutes are split like on Gators.
These are obviously the blade that particular kit is designed to be used with so there is no surprize that the notched high lifts do not work properly.
So yes, change the blades but there is no aftermarket blade I could find that has the same shape.

 

[Gord Baker]

Get used to it. Don't cut wet grass. Don't Mulch if you do. It is a normal event. You could try cutting hardwood blocks to suit and use a countersunk through bolt to hold them in the crotch.