I have found that a lot of 3 blade mowers will leave uncut strips if blade corners are worn. This is more evident if you are making a turn somewhere in the 45 degree range. They can be razor sharp and still do it. When making a turn you are feeding the grass right at the point of minimum overlap. Older Cub Cadets were the worst for this.
leaving grass uncut
- Thread starter jeffnang
- Start date
bertsmobile1
Lawn Royalty
- Joined
- Nov 29, 2014
- Threads
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- 24,995
Firstly the one thing every one else failed to mention, blades worn past their limit.
A lot of 3 blade decks are quite shallow front to back so have little room to accomodate blade overlap.
Thus a small amount of wear and you have mowhawks where the blades just don't cut.
As for belt tension.
Decke where you have a pto belt from the mower to a double pulley then another belt for the blades generally give a better cut.
This is simply because they have more contact on the middle pulley.
I see a lot of decks where the side pulleys have 180 degrees of contact with the belt but the middle pulley has about 60 degrees.
Thus the middle pulley slips and the blades turn slower which plays havock with the airflow under the deck.
I have even seen an owner reroute his belt because he thought it had too many bends in it which was breaking the very expensive belt .
The 20" shorter belt was also a lot cheaper.
A lot of 3 blade decks are quite shallow front to back so have little room to accomodate blade overlap.
Thus a small amount of wear and you have mowhawks where the blades just don't cut.
As for belt tension.
Decke where you have a pto belt from the mower to a double pulley then another belt for the blades generally give a better cut.
This is simply because they have more contact on the middle pulley.
I see a lot of decks where the side pulleys have 180 degrees of contact with the belt but the middle pulley has about 60 degrees.
Thus the middle pulley slips and the blades turn slower which plays havock with the airflow under the deck.
I have even seen an owner reroute his belt because he thought it had too many bends in it which was breaking the very expensive belt .
The 20" shorter belt was also a lot cheaper.
