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I have a Craftsman Model 917.272452 42in deck lawn tractor and at the beginning of the season I put on a new set of blades. I did notice after cutting the lawn sometimes didn't just look right to me but went thru all the normal things, check tire pressures, reset the deck, also reset the guide wheels. As I also use the machine for snow blowing I do all the cutting setups at the beginning of the year. So back to the problem ( maybe ). When I removed the blades I saw the odd to me the way they have been cutting. Because of them being new the paint showed how they have been cutting. Seems that some parts are not even cutting because the paint is still on the parts of blades not cutting. These blades seem to have a slight pitch to them so it is hard to tell if they are bent or twisted wrong from the factory. I installed another set of blades but can't tell how they cut because I will have to wait for grass to grow some before I can tell. The set I installed are the original set and have been sharpened. Am downloading pictures : I understand the high spots but if you look to the right of the photos you will see the areas I'm thinking about. Thanks in advance for the help. Picture 1-4 and 2-3 are the pairs

Looks normal to me. You have 3 in 1 blades and I’ll bet you are side discharging, which is why I’m saying normal.

At this time I have cover on and am mulching. I only use discharge in the fall because of the leaves and than I use bagging till I get all the leaves cleaned up. But even if I was discharging why would the blades not seem to cut in some areas??

Craftsman mower decks are not designed to do a good job mulching, they don’t have any baffles to keep the clippings in the air to chop them up fine. This will mean that areas of the blades do not show signs of cutting in certain areas. For your unit I don’t see anything out of the ordinary.

Hard to tell from that photo but to me it seems like the blades might be upside down
Double check you have them fitted the right way
Most will have "grass side" stamped into them.

And yes only the outer few inches will make contact with the growing grass.
If you think about it by the time the grass gets to the middle of the blade it has already been cut so it is only the clippings touching the middle of the blade.
We use a lot of swing back blades down here that are only a couple of inches long and bolted to a solid disc because it is only the tips that do any work .

I did check and for sure the blades were mounted correctly. Guess I just never noticed this before with my other sets of blades. Seems odd that they make the blades with the longer sharpened edges that don't do anything, seems that if the blades are turning all the edges should be cutting. If you look at the pictures why would it be that one blade is kind of using that whole edge but the other is not ? Guess I just can't get my head around this but trying to understand it.

OldDiyer said:

I did check and for sure the blades were mounted correctly. Guess I just never noticed this before with my other sets of blades. Seems odd that they make the blades with the longer sharpened edges that don't do anything, seems that if the blades are turning all the edges should be cutting. If you look at the pictures why would it be that one blade is kind of using that whole edge but the other is not ? Guess I just can't get my head around this but trying to understand it.

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Were these blades the same exact blade you had been using.?
I know some don't do as well as they are advertised to do..and they may on a given deck..
They (some) give them some funky name and design and claim to be the end of all blades.

No these were an exact part number replacement blade set and with them next to to other set they look the same.

Mulching blades only cut with first few inches of the blade the rest of the blade is to chop up the clippings. To do the best job of mulching you need to mow really slow.

I see no one mention that primarily the blade tip are main cutting section of the blades. It does the bulk of the cutting so it wears the most. When mulching the rest of the blade is mostly circulating the grass clippings keeping them aloft then as they fall back down at the rear of the deck the blade tip again cuts them. And the internal sharpen edge cuts the grass but not as much, even on straight blades you will find that they wear very similarly that why when we re-sharpen blades they get tapered to the tips as we must take more off the tips to remove the blunt edge.

Now as your cutting not looking right we can't see that but if the blade tips are not meeting level at the center of the deck to can cause cut problems. As well when in full mulch mode you must cut a lot slower giving the blades time to do their job. Personally this really a heavy load on the mower.

I recently did a full mulch Toro rider and I had to nearly creep across my lawn or I would stall out the deck and sometimes even the engine. It is probably why I just don't see many full mulch mower setups here in the country. We do tend let our grass grow taller between mowings. Personally I do use standard mulching blades with discharge. It don't grind up the clippings but does produce smaller clippings. And if I mow CW most are cut a second time leaving clippings that disappear fairly quickly once they are dried. I do need to spread the center of the cut area out a little but that is to be expected.

I was to full mulch my lawn I would have do it at least every other day here too which mean I would not get anything else down as 6 acres is a lot of cutting.

I have tumbleweeds, and my lawn tractor blades look a ton worse than those after just 15 minutes !!!

Just to get back to everyone that replayed and gave me some good information I just wanted to say THANKS !!! Many gave me good explenation as to why the cut looks like it does so won't worry about it.

My craftsman had the same blades and they always cut horrible. Get some gator blades. Night and day difference. Is your tractor a 42” cut?

Here is the set I use

They look fine to me. As pointed out, the blades are mulching blades only the outer tip makes first cut/contact with grass and the rest is designed to chip into finer bits.

With that said, I moved to using Oregon Longer Life 596-900 Gator Fusion G5 3-In-1 Mulching Blades on my Craftsman tractors (and all mowers) and they make a huge difference in both cutting and mulching. They are significantly heavier and spin up more slowly when engaged but once they spinning, the are fantastic. I highly support them with one caveat: many folks complain about vibration with the larger and heavier blade, but to me, it's not a big deal. I've been running them for 3-4 years and mandrels on both of the Craftsman tractors are fine and show no signs of problems from heavier blade, but, they do take longer to brake to a stop when disengaged - again due to the much larger mass.

Simple geometry will prove that the blade tip's speed is roughly 3x that of the area where the paint is still showing. Yes it's hitting the grass that much faster and with that much more force to take the paint off.

Craftsman vented decks cut best at lower settings. As cut height increases cut quality decreases. As mentioned blade speed is set with throttle lever in the notch and is designed to cut at that rpm. You can control the ground speed. Slow'n the ground speed can increase cut quality. Make sure the rear deck height is a touch higher than the front. Some grasses just do not cut good. With blade tips together in the center they should be even or a blade thickness off. Your grass will tell ya when it's to much . AYP/Craftsman decks with a three bolt mandrel are week where they mate and can bend when the blade hits something. If the blades are not bent but still not even when they meet in the center ,check for bent deck. Ya usually can see the issue around the mandrel mounting bolts. AYP did make a reinforcement metal ring installed on the deck top before ya put the mandrel bolts in. I use gator blades on a AYP/Craftsman 50 inch deck and the cut is great.

OldDiyer said:

At this time I have cover on and am mulching. I only use discharge in the fall because of the leaves and than I use bagging till I get all the leaves cleaned up. But even if I was discharging why would the blades not seem to cut in some areas??

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Blades look normal to me. I never mulch or aerate. Perhaps try cutting a notch lower and increase RPM and ground speed.

In reply to others that posted after my last post, It is a 42in deck and yes it is a challange to get a good cut but has been OK.
I am cutting at 3in blade height because other wise I seem to get alot of burnt grass from the heat. I set this right at the blades as I know that the setting on the tractor does not jive to the right height, the deck is set to 1/8 to 1/4 differance front to rear (rear being high). Do you think that 3in is still to high ?? Another thing is that I don't seem to set the speed at the setting that they have on the throttle lever for cutting just always seems way to high. I do use that higher setting for the snow blower.
And also I do have a set of those heavier blades but those end up on the machine in the fall when we have alot of leaves. I tried them in the summer a few years back but didn't see a big differance in cutting.

That is normal and the shiny area is where the cuttings along with dirt etc hit after the cut is made. Eventually it will actually wear through that area. Blades were correctly installed.

Blades are normal. Post closed.

OldDiyer said:

No these were an exact part number replacement blade set and with them next to to other set they look the same.

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This is total normal. Outer part shinny cause it is the first cut and the lift forces the cut material up and towards the center. the upwards bent section acts like a fan pulling material that was cut downwards. The finer stuff stays on the ground and the heavier stuff is recycled by the blade's airflow design to recut and "Mulch" the grass. If you look at the under side of the middle uplift part of the blade you will see some more relatively shinny or more polished surface than its's top side. The blades on the discharge side handle all material and show more polish and wear as normal, the other two are more covered by grass clippings as a heavier load is trying to migrate out and air flow is less to carry the grass away so more clinging occurs. All is typical as show in pictures.