Register free!
Search
 
     

The Green Industry's Resource Center


Click for Weather
Reply
 
Thread Tools Display Modes
  #1  
Old 04-28-2013, 09:23 AM
birddseedd birddseedd is offline
LawnSite Bronze Member
 
Join Date: Jan 2012
Location: Kalamazoo MI
Posts: 1,903
Bad advice?

Was at the dealer the other day and they were showing some stuff from a john deer rider. The mower had a measuring tool to measure the height of the deck and he showed how the front was lower than the back and said this was a feature and all decks were tipped forward because if its flat the blade will hit the grass over and over and it will end up with brown tuffs on the grass.

This true?
__________________
Quote:
Originally Posted by jrs.landscaping View Post
wait why do you prefer Scag? I thought you owned a Bobcat that mowed the first American Colonies
Reply With Quote
  #2  
Old 04-28-2013, 10:28 AM
JDGlandscape's Avatar
JDGlandscape JDGlandscape is offline
LawnSite Senior Member
 
Join Date: Feb 2012
Location: New Hampshire
Posts: 415
Yes, most people aim for their decks to be tipped forward anywhere from 1/8 inch to 1/2 inch. It helps with striping also
__________________
2005 F350 supercab 6.0 powerstroke
1999 F350 supercab 7.3 Diesel Boss V plow
1999 F350 Dump 7.3 Diesel 9' Fisher plow
2002 F250 supercab 5.4
2005 Exmark 52" Lazer Z HP
2013 Gravely Pro-Turn 460
2004 Exmark Metro 48" Walkbehind
redmax and Husky blowers and trimmers
1990 John Deere small tractor
2012 8.5x18 with a 3' V Enclosed trailer
Reply With Quote
  #3  
Old 04-28-2013, 12:09 PM
Ridin' Green Ridin' Green is offline
LawnSite Fanatic
 
Join Date: May 2011
Location: Michigan
Posts: 8,426
I don't think it turns the grass tips brown just from being hit over and over as he put it. They get hit over and over by the front end of the blades even when you have the correct pitch, but under a flat deck (no pitch) the blades drag in the grass front and rear which uses extra fuel, and Deere claims over time will wear the crank bearings much faster.

Having the blades pitched down in front does help with striping like mentioned above. How much depends on the brand of machine, deck type, and blade type.
Reply With Quote
  #4  
Old 04-28-2013, 12:17 PM
birddseedd birddseedd is offline
LawnSite Bronze Member
 
Join Date: Jan 2012
Location: Kalamazoo MI
Posts: 1,903
so I should tip my old bobcat forward? my Tito 62 in rider is tipped already?

this means I will have to do much more grinding on my blades as some of them were damaged right on the tip.

why do blades have half of the blade as a sharp edge if only the very tip is touching the grass?
__________________
Quote:
Originally Posted by jrs.landscaping View Post
wait why do you prefer Scag? I thought you owned a Bobcat that mowed the first American Colonies
Reply With Quote
  #5  
Old 04-28-2013, 12:26 PM
Ridin' Green Ridin' Green is offline
LawnSite Fanatic
 
Join Date: May 2011
Location: Michigan
Posts: 8,426
The only way to know how much pitch you need is by looking at your cut afterwards very closely. Look for stringers or an uneven cut appearance. If you aren't getting much of a stripe left behind, you probably need to add a little pitch.

When you think about it, if your blades are pitched say 1/4" down in front which is average, at any one moment when the blade is perfectly straight forward front to rear, the front half is only pitched an 1/8" which isn't far from dead level really. Now add in forward travel over rough ground etc (even a smooth lawn has small bumps) the blade is constantly changing its horizontal relationship relative to the ground. Having a longer cutting edge makes sure that ALL blades of grass get cut. Also, if you have damage to the tips, or outer edge of the cutting edge, make sure to correct that. A blade with a rounded corner at the tip will leave skips and stragglers behind a LOT more than a properly ground cutting edge will.
Reply With Quote
  #6  
Old 04-28-2013, 12:43 PM
Blade Runners's Avatar
Blade Runners Blade Runners is offline
LawnSite Senior Member
 
Join Date: Apr 2012
Location: Woodlawn, TN
Posts: 913
That's good info to know about the rounded blade tips. I've seen in videos where they say to square off the end of the blade but they never explained why.
__________________

Scag mowers
++++++++++++++++++++++++++
www.ClarksvilleLawnCare.us

"Always do your best. What you plant now, you will harvest later."
-Og Mandino
Reply With Quote
  #7  
Old 04-28-2013, 12:54 PM
Ridin' Green Ridin' Green is offline
LawnSite Fanatic
 
Join Date: May 2011
Location: Michigan
Posts: 8,426
Quote:
Originally Posted by Blade Runners View Post
That's good info to know about the rounded blade tips. I've seen in videos where they say to square off the end of the blade but they never explained why.
A nice square corner on the end of the cutting edge makes a difference on all mowers/blades, but especially so on mowers with more than one blade. If all the tips of the cutting edges are rounded over, even just a little, grass blades will be able to slide in between the tips of the blades (so to speak) and pass on through without getting cut. Multi blade decks with rounded correns on the blades are prone to leaving uncut strips of grass right where the blades would overlap on each pass over the lawn. If you have a three blade deck, and you are getting two uncut strips or light rows of "skips" left on each pass, it is caused by the rounded corners of the cutting edge 99 time out of 100.
Reply With Quote
  #8  
Old 04-28-2013, 01:02 PM
birddseedd birddseedd is offline
LawnSite Bronze Member
 
Join Date: Jan 2012
Location: Kalamazoo MI
Posts: 1,903
Quote:
Originally Posted by Ridin' Green View Post
A nice square corner on the end of the cutting edge makes a difference on all mowers/blades, but especially so on mowers with more than one blade. If all the tips of the cutting edges are rounded over, even just a little, grass blades will be able to slide in between the tips of the blades (so to speak) and pass on through without getting cut. Multi blade decks with rounded correns on the blades are prone to leaving uncut strips of grass right where the blades would overlap on each pass over the lawn. If you have a three blade deck, and you are getting two uncut strips or light rows of "skips" left on each pass, it is caused by the rounded corners of the cutting edge 99 time out of 100.
I have never squared the end of my blades. i just kept sharpening untill i got past the rounded part and it was naturally square from sharpening.

thanks for the info. i guess you could say that being "level" is not an exact science. ill go ahead and tip my bobcat forward one notch. i do not know if i have an adjustment for my toro for this however. if so i do not know how to use it, or have seen it.

thanks again
__________________
Quote:
Originally Posted by jrs.landscaping View Post
wait why do you prefer Scag? I thought you owned a Bobcat that mowed the first American Colonies
Reply With Quote
  #9  
Old 04-28-2013, 06:05 PM
Magna-Matic's Avatar
Magna-Matic Magna-Matic is online now
Sponsor
 
Join Date: Jul 2001
Location: Waldo, Wisconsin
Posts: 798
Hello All,

Here is a link to one of our educational sections for some more info about lawnmower blade tip geometry. With some images about the reliefs that make up the cutting tooth of the lawnmower blade.

http://www.magna-matic.com/blade-education.html

Grinding back the blade correctly with one even cutting edge angle (usually 30 degrees) so that the pointed corner or TIP emerges is the definition of a sharp lawnmower blade. Severely rounded tips of the blade also leave grass un-cut between multi-blade decks, and cause the need for double cutting most of the time.

Glad to see this being discussed.

We'll be adding some more educational bulletins in May to that page link, with information of how much of the cutting edge is used at "x" rpm and "x" miles per hour.

Thank you,
__________________
Gerd Ferdinand Bauer II

Magna-Matic Corporation
Waldo WI USA
800-328-1110 (toll free USA & Canda)
920-564-2366 (PHONE)
gbauer2@magna-matic.com
www.magna-matic.com
www.magna-matic-direct.com
www.youtube.com/magnamaticcorp
Reply With Quote
  #10  
Old 04-28-2013, 11:48 PM
birddseedd birddseedd is offline
LawnSite Bronze Member
 
Join Date: Jan 2012
Location: Kalamazoo MI
Posts: 1,903
huh. I thought it was 20 degrees. I try not to get a razor sharp blade when I sharpen them. but honestly I don't really know what I'm doing. frankly my small grinder probably isn't up for the task anyway.
__________________
Quote:
Originally Posted by jrs.landscaping View Post
wait why do you prefer Scag? I thought you owned a Bobcat that mowed the first American Colonies
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump





Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ©1998 - 2012, LawnSite.comô - Moose River Media
All times are GMT -4. The time now is 04:05 PM.

Page generated in 0.07469 seconds with 9 queries