Mowing faster
 

When mowing my fields occasionally I mow over some barbed wire or baling wire, which wraps around the blades.
Have to go back to the garage and take the blades off to clear out the wire.
While I have the blades off I usually sharpen them.
The freshly sharpened blades allow me to go 2 to 3 times faster. But only for 10 to 15 minutes max then I look back and a bunch of weeds and grass are left sticking up.
Then I'm back to a crawl, as to give time for the blades to just beat the grass and weeds into submission.

So I figure blades that stay sharper longer are the way to go.
First thing I did was search around. Didn't find much. I did find that standard blades are .125 to .135'' and that the heavy duty ones are .187'' inches.
Can't buy them so I will have to make them. Mower blades are fairly hard steel already but not nearly as hard as chromium carbide hard facing rod.
The smallest hard facing rod I have is .125 inches. So I would probably burn through a standard mower blade. Just need to make sure I have 187 thickness and go from there. I think all I will be able to do is build the blade back up with wire feed welding then weld the underside with hard face rod.
Any blades I weld on will have a heat sink on them so the welding heat only effects the area immediately around the weld it's self. That way the heat can't spread put and ruin the heat treat and temper of the rest of the blade.

I also have a brush flail shredder on my tractor, it needs new blades, the replacement blades are usually around 1/2 to 5/8 inches thick, I can just weld those up easy. Build up the bevel with oil pipe line welding rod (11018) which i have and is used commonly as cheap hard facing rod. Then weld underside of the blade with real hard facing rod.

I figure if I can keep the blades sharp I can just about cut time, fuel, number of blade replacements and oil changes in half or better. So its worth looking into.

I'm going to start small with my little 4hp push mower. It likes to have a sharp blade. Then scale it up to the riding mower and then the tractor.

Im wondering,
if you increase the blade rotation speed with a larger pulley or gear if it would give a similar effect as slowing down the mowers drive speed

The mower has plenty of power, it probably could spin the blades faster. But then that works the motor harder and burns more gas.
I want to try making it more efficient first before just going to brut force.

Thinking about the whole mechanics of a mower blade, the edge you need to keep ultra sharp is the leading edge of the lower portion of the blade, not necessarily the whole thickness of the blade.

Would it be possible to drill the blade, tap it and attach a hardened cutting element to the existing blade? I know some of the old Snapper high lift system blades for rear bagging had additional wings on the trailing edge of the blade to create the high lift on a surface prone to high wear. (the quartz sand in my backyard is especially rough on blades).

I have seen these replaceable screw on blade tips on ebay.
Years ago I had a mower with them. I sharpened them a few times and I don't recall them being any harder than a standard mower blade.

All the mower blades that I have ever sharpened can be sharpened with a file, indicating a fairly soft steel. From what I understand, they make the blades out of soft, typically non-hardenable, steels to be able to take the impact of hitting rocks and other things and not shattering.

Though I find adding the facing rod an interesting idea, I think the unequal heating of the mower blade is going to cause it to warp and bend and make it unbalanced in the end. I think you might have better luck with "pack carburizing" the mower blades.

I can reballance them.
Carburizing is more of a surface treatment the you have to reheat treat and temper the blades. Then the blades may change shape during the process.

Another option is to buy Oregon tungsten carbide tipped blades. They are only 2 to 3 times the price of the junk they sell at lowes.
But since I already have the hard face rods and welding rig I am going to try this first.

From just mowing around my yard for this season only the blade ends are already starting to wear thin.
I'm going to take dial calipers to lowes and buy 0.187 inch thick blades, if they have them. I don't think they have any that will fit craftsman and are .187 thickness. The heaviest blades lowes has look like about 0.15 inches thick.

I found new 0.187 inch thick blades at the local echo dealer for $10 each. I will try hard facing the under side of these blades.
Then ordered some high abrasion and medium impact resistant 3/32 inch hard facing rod.
While cleaning out the shed I found some old worn out .187 thick blades I can practice on. I will practice on the inner non worn out part of the blade.

I got them done.
The mower blades got one bead on the underside.
The brush shredder got several beads ran on the underside.
I don't know the effect yet because the blades have to wear back to the hard facing.

Mower blades were tested to failure. As in it broke.
The mower blades were last year's medium duty 3/16 blades so they were already kind of worn down. The high alloy homogeneous hard face rod did very well when applied to the blade. This uses high alloy tungsten and chromium filler.
The carbide crystal bearing hard face rod did not. It was so hard it cracked with in 20 to 30 minutes. Don't use carbide hard face rod on mower blades.

I applied the carbide bearing rod to my brush shredder blades, these are between 1/2 and 5/8 inches thick. They should not Crack as easy.

Next time I hard face mower blades I am going to use new 1/4 inch thick heavy duty blades.

We use hard facing rods to re-build the cutting surface on our wood chipper knife. first is the actual factory metal, then an intermediate rod of tougher, harder material, followed by the hard facing rod, then some time on the wetstone. this seems to work quite nicely, and chips up buckthorn for much longer before it goes dull again. DC SMAW tombstone welding like a good farmer.

We manufacture and resharpen blades for the carpet tile industry. They are made of ASTM-A2 and heat treated to R52C.

I designed a machine about ten years ago that used some of our A2 drops for a wear surface exposed to sand and glass beads. The wear block seems to last about the same whether heat treated or not. Thus we now deliver them without hardening to save money.

If you can locate A2 steel in 0.12 to 0.18 thickness you could try making bolt-on wear tips. In the unhardened condition it takes quite a beating.

I have tried to scrounge some A2 to make mower blade tips but everything we manufacture here is either 10MM or 7/16". Some OSB plants use 5/32 inserts for their chipper knives. We've never made them though.

Having the carburetor working properly helps too.
I just rebuild the carb and replaced a lost spring on the governor on my 18.5hp V-twin, now it feels like it could power a 54 inch deck with ease in all but tall weeds.
The carb had 2 bad seals that would flood the engine with fuel under heavy load and the gov spring wasn't allowing the engine to run at full speed.

How long is your grass/weed before you cut it?

The last guy didn't mow it for 4 or 5 years.

The big difference between commercial mowers and consumer mowers is the blade speed. The CPSC has regulated homeowner mowers to a certain feet per second. I forget what it is off hand. Commercial mowers don't have that problem so they run the blade at higher speeds resulting in a better cut and better ground speed.

So yeah increasing the blade speed is a good thing however most consumer mower decks are not built that well and the blades need to be balanced much better due to the higher speeds.

Anyone remember the old lawn boy mowers? They were two stroke, light weight high blade speed and a great push mower though odd wheel arrangement on it.

I actually have been reconsidering upping blade speed since I rebuilt the carb and replaced a missing spring on the governor.
My mower has ridiculous power now and burns less fuel.
So I could run at a lower engine RPM for most mowing if the blades would spin fast enough.
Problem is a good portion of my field is way too bumpy to run the mower along as fast as I would like to go.
So if I could find smaller sheaves for the blades or a bigger one for the engine drive shaft.

Dont slow the engine rpm. Always mow at full throttle. Running the mower at slower rpms reduces its ability to cool. This is why most push mowers no longer have a throttle. Too many burned up engines from people not following directions and mowing at full throttle. On push mowers you dont need idle as you are mowing or you arent. Riders need to have idle sped but some now are also set at full throttle.

I bought some close out Oregon gator blades.
Problem is they don't fit.
But in my lawn mower junk collection I have left over "universal blade adaptor kits" and a spare blade spindle.
So I can make them fit.

Once my experimental blades wore back to the high alloy homogeneous hard facing rod it stayed sharp a little longer but, meh, not really worth the trouble.

I think found the final solution to mower blades that stay sharp longer pretty much for the life of the blade.
Laser-edge dot com.
They perfected what I was trying to make.
This company applies a paper thin very hard coating to underside of the mower blades and they make them for all different makes and models.
I needed star pattern 21 inch mower blades for craftsman, they didn't have any. But they had blades for professional grade Husqvarna 60 inch mower that uses 3x21 inch blades to make 60 inches. Husqvarna and craftsman use the same 5 point star pattern so I ordered some. $30 each plus $15 shipping.
Shipping was per order if I knew that these worked as well as they say they do I would have gotten 3 or 4. But I will start with 2 for now.
If they stay kind of sharpish they will 100% be worth it.
The company says for best results use in areas with gritty Sandy soil, which describes NM perfectly.

When I sharpen the standard tool steel blades I can run the mower full speed through knee high field grass, but after 20 minutes of mowing I have to start slowing way down or I miss more than I mow.

Will be interested to hear how they hold up. I don't bother sharpening since the sand eats them for breakfast anyway.

FYI the 5 lobe star on the craftsman and the husky are the same as they are both made by AYP. AYP was purchased by Husky. Unfortunately their line of mowers has lost allot of market since then.

Sears bought mowers from AYP and MTD. The AYP ones were the higher end models. AYP was bigger in the riding mower line at sears than the push mower line.

The 6 lobe blades are MTD. MTD riding mowers are more plentiful now however bulk blades are still cheaper for the AYP/Husky mowers. These are the ones I am going to order for mine. Well I was going to put a link in but the web link button in the UBB here doesn't work. It just dumps the whole link in instead of making a highlight able link.


I'm going to end up having to get a bagger for my mower since I am getting tif 419 bermuda to grow and it's so far the best growing grass I have ever tried but you can't mulch it as it is not good for the grass.
The tif is a nice dark green thick and soft doesn't need much water or fertilizer and is very heat tolerant. I am mowing it a little bit high at 1.5" but just because it's been over 100* every day. It grows better at about half an inch. If you let it get tall it won't spread and will be thin and spindly.

First impression is these blades are worth it.
They are the heaviest I have tried to date, I have ordered stuff from online, bought from the local mower shops, ect.
The "stay sharp secret" is non-homogeneous chromium carbide granules adhering to the under side of the blade.

Been using the laser edge dot com blades for almost a year. Yeah they rule in abrasive soil that wears normal steel blades blunt after a several hours of use.

I got a craftsman T2400, 46 inch, 19hp single cylinder. It was a pile of parts probably about 6 years old, barely any hours. Still had the factory oil, not even blacked out and had oil easy change attachment that never had been wet with oil. I put the standard slingblade pipe nipple and elbow oil drain on there.
Well I got it all together and just needed blades, I got cheap lowes blades, but I ran out of daylight so I might return them and get some mower shop blades.
It doesn't appear that fisher barton makes any approximately 23 inch "eversharp" blade. I would even go so far as taking a regular 5/8 inch hole and punch out the star pattern by hand. But I guess 2 blade, 46 inch deck mowers aren't "commercial enough" for them to bother with.
The only reason I got eversharp blades for my little 42 inch mower was because husky makes a 60 inch commercial mower that uses 21 inch star hole blades.

Well I am going to try increasing the blade speed.
Turns out the old smaller 42 inch deck pulleys will fit on the 46 inch deck spindles. So I'll be replacing 6.25 inch pulleys with 5 and 3/16.
Stock is right about a 1:1 ratio. Now they will be over driven to about 4,000 rpm, about a what, 15% over drive? That required a 5 inch shorter belt. Everything is ready to go for the test tomorrow.
Will it work or will it just chew up belts?

As an alternative or maybe even an upgrade to the fisher barton eversharp blades there are blades made by meg-mo they are miniaturized 4 blade "bush hogs" because the blades pivot and don't have to be flexible to absorb impacts so they are really hard and really high alloy.
They don't stock any star pattern blades but they say they will make anything.

That sounds like a decent improvement.

I would be more worried about belt slippage which is a common issue on homeowner mowers since they are made to be more forgiving.

Yep definitely getting accelerated blade ware. But dang it cuts good.
I went with a 100 inch belt. A 4L101 gets real loose after a while. A 4L100 is almost too tight at first, like the blades don't want to stop till I break the new 100 inch belt in.
Tractor supply had a 5L100 and it wouldn't fit at all. But I think a longer 5L would work.

I was over on bitog and it looks like the briggs 19hp single cylinder is known for blowing head gaskets. So that could suck. I'm giving the engine a few minutes of idle warm up, then throttle up and engaging blades probably around 2,000 rpm for about 2 minutes before going full throttle.
Then for shutdown I let it idle no load for 2 or 3 minutes.

This winter my project is going to be to take warn blades, not warn out, build them up with regular old L56 rod, homogenize the weld to the base metal, forge them into shape and heat treat them. If I can remember what they're called, buy some of the hard facing brazing rods if I can remember what they're called. They have a weird name.

We had a stick welder and some black colored rods (I think nickel) that would work for that. I have a ice chisel (used for other stuff too) that I welded onto the edge. Its been working for 20 years! I think on a mower blade it wouldn't last that long, but it was easy and no forging and heat treating.

Let us know how it works out.