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bobbygedd
04-30-2006, 08:34 AM
generally, i never worried about having real sharp blades. this year, i've decided to carry sharp blades on the trucks, and replace them perhaps twice - three times a day. i'm finding that- you get an obviously nicer cut on the first lawn after putting the new blades on. but, by the 5th or 6th lawn, your blade isn't sharp anymore. our lawns are only 3-4,000 sq ft each. there is no way i'm gonna change blades after every 6th lawn. my conclusion is that- though having a razor sharp blade is beneficial, it just isn't practical. the only lawn that truly benefits, are the first maybe 4 lawns, after the blade change. opinions?

geogunn
04-30-2006, 08:47 AM
dulling blades in 15,000 to 24,000 sq/ft?

I believe I'd buy some better blades if I were you , bob.

GEO

rodfather
04-30-2006, 09:21 AM
dulling blades in 15,000 to 24,000 sq/ft?

I believe I'd buy some better blades if I were you , bob.

GEO

I tend to concur with GEO...see if you can't get a better blade that will hold up longer BG.

dad
04-30-2006, 09:55 AM
To go along with blade quality I am wondering what you use to sharpen them. You need to pay attention to your angle and finish with something other than a grinding wheel.
I myself am very anal about sharp blades. I change them once a day need it or not. It just looks better.

JTF40
04-30-2006, 09:57 AM
Belt sander - 80 or 120 grit !!!!!!:usflag:

topsites
04-30-2006, 09:59 AM
I am sorry but I am with bg on this one, the razor's edge on a blade really only lasts about 20 minutes, after which it's still sharp but as you can see, it dulls constantly and at a pretty amazing rate. I don't doubt that different finishes on the blade affect this some, but once mine are dull anyone can see that no matter how sharp they were earlier, there's no way they wouldn't be dull now. On that same note, I'm a bit anal about the sharpening too and am not disagreeing that the sharper the blade on your first yard, the sharper it still is for the last.

My props are larger than bg's and mine are dull after 3-4 yards but much like bg, am in no mood to change blades in the field first, and sharpen at least twice as many blades as I already do second.

I just change them daily, bg... That's the best we can do, the first 4-6 yards look a little better than the last few but most folks never know the difference and since the schedule and the way I cut it doesn't really take preference over who gets cut first, it's all a bit of luck of the draw, everybody gets the razor's edge on their turf sooner or later, but not everytime.

p.s.: My truck sometimes kinda steers itself towards the nice yards where folks spend good money earlier in the day and the run-down lots where nobody cares later, don't really understand it but it's just kinda like that (I said sometimes).

geogunn
04-30-2006, 10:12 AM
topsites--I don't believe either you or bob sharpen your blades "razor sharp".

in fact, I don't think the two of you working together could get a mower blade "razor sharp".

razor sharp in terms of an "edge" indicates one can "shave" with the blade.

use "sharp" blades? sure. use "razor sharp" blades? bs.

GEO

David Haggerty
04-30-2006, 10:43 AM
I've figured out thet having the correct angle when sharpening has a lot to do with how long the blade stays sharp which in turn lengthens the life of the blade.
I've noticed everyone tends to sharpen at too sharp of an angle. Like they were sharpening a knife or something. Me included.

The proper angle for my big Toro's is 40 degrees! That's pretty blunt! It looks like it won't even cut grass. But it does. And does it better than any other angle. If the angle is too sharp the edge won't last any time at all.

I have one of those adjustable angle squares. (I don't know the proper name) It has a wingnut on the corner and a little scale on the side where you can read the angle the square is set at. Think I gave $5 for it at Harbor Freight Tools.
I hang it on the wall behind the grinder. I also looked up the proper angle for each mower's blade and wrote it on the wall with a felt tip pen right there by the grinder.
It saves me time grinding. Saves the blades. And they stay sharp longer.

I'll just bet if your sharp blades aren't lasting till noon, you're sharpening at too sharp of an angle.

Dave

CutInEdge Lawn Care
04-30-2006, 10:43 AM
If your not tearing or browning the tips, then I say sharp enough. I change blades daily and use a RBG21 blade grinder and balancer. I dip the blade in cool water just for good measure to bring bk an temper. I dont think I get blade hot enough in most cases but I made water sizzle a time or 2. Anyone inventing a self-sharping system (like a self cleaning oven) hit the self sharp button and drive to next job and walah.

CutInEdge Lawn Care
04-30-2006, 10:46 AM
Ours are sharpened at 30 degrees. Scag's

lampeslawnservice
04-30-2006, 10:55 AM
I used to have the same problem bobby till I bought the magnamatic this spring. Not only do blades stay sharp longer they are quicker to sharpen. And they are razpr sharp. And believe me I am not easy on blades, lots of house with trees

ACEMowing
05-01-2006, 12:49 AM
I think when it's sharpened too "sharp" the thin metal edge ends up getting "rolled".... that makes them go dull real fast.

lawnworker
05-01-2006, 01:24 AM
I think some people go overboard on this idea of having super sharp blades. The shear of the grass blade just needs to be clean enough so that the blade closes quickly. I find that once a week works great for blade sharpening.

Envy Lawn Service
05-01-2006, 01:25 AM
Well, the first thing you have to do is STOP using cheap aftermarket blades.
Unless you can find some out of better quality steel, you cost yourself more in maintenace than you save on the blades.

Once you do, it is also important to never let the blades really get dull. This way you take them off and touch them up instead having to try to grind them out back to sharp. I NEVER grind blades back sharp that often. If they need grinding for some reason I usually just put them in backstock.

Now I run Marbane steel blades whenever possible.
If I told you the hours I'm getting between sharpenings, you wouldn't believe me.
They cost more, but it's totally worth it... (just don't tell them that)

bobbygedd
05-01-2006, 07:14 AM
where can i, get a set of these blades? and how much are they for 36"

Richard Martin
05-01-2006, 07:34 AM
I gonna get attacked for this but here goes...

Putting any kind of sharp angle on the edge of the blade is wrong. I was taught a long time ago by an "old salt" how to properly edge a mower blade. As has been pointed out numerous times in this thread already a razor sharp edge lasts literally for minutes.

What I do is get the blade semi-sharp and then flip the blade up so I can run the edge of the blade across the grinding wheel and put a flat edge, about 1/16" to 1/8" across the whole length of the edge. This flat edge lasts a whole lot longer and actually gives the blade 2 edges to cut with.

Precision
05-01-2006, 07:41 AM
where can i, get a set of these blades? and how much are they for 36"

Most mower shops carry an assortment of blades from various vendors. If not, do a google search for an internet provider. Most OEM blades are made by Rotary for the manufacturer, so buying direct from rotary is the same blade (in most cases) just cheaper.

lampeslawnservice
05-01-2006, 09:00 AM
I put a razor sharp edge on my blades and they last for 20 and 30 hours. And 9 out of 10 times they are so sharp when I change them they hurt my hands when I am holding onto them to break them loose. Never could say that before the magnamatic.

Tvov
05-01-2006, 09:15 AM
Really, the only times I find a visual difference in cut with blades is when they are "really sharp" or "really dull". Pretty much anything in between, there is not that much of a difference. We sharpen and change blades about once a week, more if needed, and they seem to work fine. I don't see how any small increase in cut quality would make up for the time spent changing blades in the middle of the day (especially with employees, they'll turn that into an hour+ long operation/break time). But whatever works for you!

Remsen1
05-01-2006, 10:19 AM
Rich, I'm trying to visualize, what your saying but I can't. Forgive me for being slow but I was wondering if you could go over that again for me? I am curious and always willing to try something new. I too like the advice from the old timers. I think the advice from these old timers (at least the ones not talking out of their asses) is more valuable than alot of other advice cause it comes from a time when technology couldn't compensate for poor technique.

Remsen1
05-01-2006, 10:24 AM
So far I agree with Cutting Edge and TVOV. "no brown tiip=sharp enough"

If I were mowing some upper end, highly manicured, extremely lucritive properties, then I would consider changing blades at lunch time and pricing all the lawns accordingly. Unfortunately or Fortunately, depending on how you look at it, I know none of my current customers would even notice if I changed my blade maintenance schedule and I would bet money that none of them would even notice brown tips, but I would.

Richard Martin
05-01-2006, 11:11 AM
Rich, I'm trying to visualize, what your saying but I can't. Forgive me for being slow but I was wondering if you could go over that again for me?

I didn't explain it very well. Try this visualization...

This is with the edge of the blade up.
Standard "razor sharp" blade edge

l\
l..\


This is the result....
_
l..\
l....\

mr.we.mow.grass
05-01-2006, 11:44 AM
I didn't explain it very well. Try this visualization...

This is with the edge of the blade up.
Standard "razor sharp" blade edge

l\
l..\


This is the result....
_
l..\
l....\
I will agree with richard my Dad used to sharpen many different tools as a small business. He showed me this trick many years ago. Doing this does give two edges to cut with and it will not row the edge of the blade near as fast.

I am waiting on 4 edged blade, something like my razor I shave with!!!!!!!! hehehe
Hope this helps
Mel

2manymowers
05-01-2006, 12:00 PM
I didn't explain it very well. Try this visualization...

This is with the edge of the blade up.
Standard "razor sharp" blade edge

l\
l..\


This is the result....
_
l..\
l....\

Richard,
Interesting concept. Can you tell any differnce in the way the mower cuts compared with a standard sharpened edge? It looks like as soon as the "corners" on your blade rounded a little from use, that you would have a very dull blade. Obviously that is not your experience. I may try this with one set of blades. Thanks.

Richard Martin
05-01-2006, 12:24 PM
Richard,
Interesting concept. Can you tell any differnce in the way the mower cuts compared with a standard sharpened edge? It looks like as soon as the "corners" on your blade rounded a little from use, that you would have a very dull blade. Obviously that is not your experience. I may try this with one set of blades. Thanks.

The difference is the corner doesn't round nearly as fast as the normal edge since you have a whole lot more steel to try and wear down. They cut just as good. It also takes a lot less time to sharpen the blades too.

topsites
05-01-2006, 12:53 PM
topsites--I don't believe either you or bob sharpen your blades "razor sharp".

in fact, I don't think the two of you working together could get a mower blade "razor sharp".

razor sharp in terms of an "edge" indicates one can "shave" with the blade.

use "sharp" blades? sure. use "razor sharp" blades? bs.

GEO

Ok no you can't shave with it but stick your hand under the deck without thinking and you will get cut and it doesn't feel good. Going back to what I said earlier, even if it is razor sharp it is still going to be dull in 3-4 yards, might last 5-10 minutes longer if it lasts that long.

Envy Lawn Service
05-01-2006, 12:55 PM
So Richard, you mean to tell me you run the grinder across the EDGE?
So that in effect, it's like cutting with the back side of a kitchen knife?

Let me know how that works out for you when you start cutting some NC turf.

topsites
05-01-2006, 12:55 PM
I'll just bet if your sharp blades aren't lasting till noon, you're sharpening at too sharp of an angle.

Dave

Not to disagree but I am thinking too lean of an angle, meaning you're now sharpening them at a steeper incline or angle than before so you are correct because I always thought the more edge or ground metal there was, the better but I will take your advice seriously and try a closer to vertical angle rather than almost horizontal, so to speak.

I like the double-edge approach, I must admit that one caught my attention.

Soupy
05-01-2006, 02:33 PM
Don't forget to check your RPM's regularly. A slow blade tip speed can cause the problems your describing.

jameson
05-01-2006, 03:02 PM
Really, the only times I find a visual difference in cut with blades is when they are "really sharp" or "really dull". Pretty much anything in between, there is not that much of a difference. We sharpen and change blades about once a week, more if needed, and they seem to work fine. I don't see how any small increase in cut quality would make up for the time spent changing blades in the middle of the day (especially with employees, they'll turn that into an hour+ long operation/break time). But whatever works for you!

I second this. We change blades once a week, cut quality has not suffered. One exception that comes to mind is the few weeks after aerating lawns, blades are changed as needed/daily until plugs are gone.

James

Charles
05-01-2006, 03:39 PM
I keep my blades slanted and razer sharp. I don't buy the el cheapo blades so they stay reasonably sharpe all day.

Runner
05-01-2006, 11:59 PM
Mine are done about daily, so there really isn't an issue with them being done at a leaner bevel or real sharp. We DO do them real sharp, but they always seem to stay sharp. Like I say, we are swapping out almost daily, anyway. These ARE with softer blades, as well. (Oregon or Anderson)

K c m
05-02-2006, 12:02 AM
I sharpen a set of blades every 3-4 days. Since 3/4ths of my lawns are double cut.

topsites
05-02-2006, 12:08 AM
I didn't explain it very well. Try this visualization...
This is the result....
_
l..\
l....\

Hey I did that today and it RULES! All I did was sharpen the top as usual, zinged it along the bottom right quick and then just zinged the grinder along the edge vertically real light, barely 1/16" of an inch or so of a double edge... I figured let me try a mild sharpening just in case and wow you are right:
It takes a LOT less time to sharpen, it wastes a LOT less steel and even the burrs and the nicks come out nicer looking in the end (even thou they're still there). Even mild sharpening restored what I started with almost instantly.

Then I must'a sharpened a dozen blades in short time before I quit, I'm actually looking forward to doing it again. By now in my 5th year it had gotten to where I about couldn't stand to sharpen blades anymore, the mere thought of spending 30-45 or 60 minutes with that stuff used to make me want to puke, I actually bought more NEW blades just because I was starting to hate it so bad and the worn pile kept getting bigger and bigger lol.

All that's left is try out how they work tomorrow but I am almost for sure they will do real good, it just looks so good on the blade that little 1/16" sharp flat double-edge thing.

Thanks, that was a really great idea!

Richard Martin
05-02-2006, 05:22 AM
Thanks, that was a really great idea!

I'm glad I could help.

CutInEdge Lawn Care
05-03-2006, 12:54 AM
Richard, are you running doubles also? Sorry if mistaken. Thought I read where you have been using doubles also. My grandfather used to sharpen that way. He also had one heck of a razor strap. Ouch!!!!!

Richard Martin
05-03-2006, 05:35 AM
Richard, are you running doubles also? Sorry if mistaken. Thought I read where you have been using doubles also. My grandfather used to sharpen that way. He also had one heck of a razor strap. Ouch!!!!!

I've used lots of combos of blades over the years. For grass cutting with my Dixie I currently use a double on the left-hand spindle only. For some strange reason my Dixie will leave a small pile of grass right at the front of the deck if I come to a complete stop in heavy grass. It doesn't do it with a double on the left spindle.