OT. what type of welding rod is used to put a hardened edge on a lawnmower blade

[Modat22]

I used to know this but I forgot, there is some sort of welding rod a person can use to weld a hardened bead on the sharp side of a lawn mower blade. From what I remember it was a red colored rod.

Anyone know?

[Bro. Noble]

Are you thinking of 'hard surface' rod?

[UNCLEBUCK]

Nickel rod would be my choice ok 

[bitternut]

I think you are thinking of a rod called stellite. Very expensive and very hard. Back when I used to run snowmobiles we used to put a layer of that on the ski skegs. No sparks when you crossed the road with them. We used to run down the roads quite a bit and if you did not have treated skegs on your skis they would wear out pretty fast.

[sawguy21]

Lawn mower blades are made of austempered steel and are not hardened for safety reasons. What would happen when that blade hits a rock or water shutoff at 3000 rpm? It would shatter, not bend, and the pieces would become lethal shrapnel. I know it is a pain to remove and sharpen them, mine needs to be done.

[scsmith42]

I've been down this same road.

Here on the farm I have a lot of grass to mow, and am always mowing sticks, stumps, whatever seems to be hidden in the leaves and pine straw.  This necessitates frequent sharpenings.    When I first moved out here mowing was a real chore - I averaged 10 hours a week between a Craftsman rider and Hinomoto tractor / finishing mower during the heavy growth season. The rest of the year was about 5 hours a week.

I went the hard surface route myself about five years ago, and used the blades for a couple of mowing seasons.  They did last longer between sharpenings (about 30% increase), but it took a LOT of time to weld up the blades and grind them down (being hard surface they don't grind down very fast!).

After I bought the Scag the mowing time decreased significantly (about 70%), but I was still mowing the same amount of grass so a lot of sharpening still took place.  However, when I added a vehicle lift to the barn sharpening became much less of a chore.  I simply run the mower up into the air and sharpen the blades in place with a 4-1/2" Makita disk grinder with a flap wheel disk.  It only takes a few minutes to get them sharp and the flap disk removes metal at a lower temperature - helping to maintain the temper in the sharpened edge.  I grease the Scag at the same time and give it a maintenance once-over.  Since then I no longer do the hard surfacing.

Sawguy -  you have a valid point about the entire blade not being hardened; however my logic was that if I only hardened a 1/2" wide strip on the outer edge of the blade (the cutting edge) the rest of the blade would still be tempered and bend rather than breaking.  This did eventually prove to be the case as I bent several of the hardened-edge blades.

Just ask a welding shop for hard surface rod (and as bitternut mentioned Stellite is one type of hard surfice rod - there are others as well).  They typically sell it to companies that do a lot of welding on heavy equipment.

Regards,  Scott

[Qweaver]

Putting a stellite weld along the sharp edge of a lawn mower blade would be tricky and would leave a bunch of grinding to get back to a sharp edge.  Hardy worth the time unless you were welding on a very thick blade.  I only ever TIG welded hardsurfacing rods and don't know if they could be Oxy/Acet welded.

I have @ 50lbs of various alloys of stellite on the shelf in my welding shop in Texas left over from my valve repair days.  I'll never repair valves commercially again so it will probably just get sold at auction some day. (not too soon I hope) :D

[Modat22]

Hey guys thanks for the information, I've got an old bushhog that has the blades are non removable (previous owner welded the bolts) the blades are in serious need of replacing and I don't want to buy a new blade hub. The Stelite rods where the ones I couldn't remember.

Thanks again
Sam

[UNCLEBUCK]

I sharpen my mower blades on the bench grider ,takes about a minute per blade , never know where my hounds left there deer bone pile but I will find it  :D

[Tim L]

blades are cheap, rods are not. I would buy new blades

[Furby]

That depends on what kind of blades ya have!
Personally I don't like spending $38 on a pair of blades that only last a season and a half or so.
But I don't think I'd go through the trouble of putting a hardened edge on them either. :-\

[Skytramp]

personally I use a 6011 to build up the tips, it would work fine on the whole blade, it would be a little harder than the blade and wouldn't be as prone to chip or break.  welding on a lawn mower blade is some what dangerous,  after welding let the blade cool down naturally.
Skytramp;

[Buzz-sawyer]

What you need are called hard surface rods, or wear surface rods...sorry I dont have a number specific, but at the welding storwe they will hook you up if you tell them hard surface....I have welder thousands of themonto cutting edges of loaders, and wear surfaces on primary crushers, and classifiers...good, cheap and better than new fix...you are on the right track ;)

[sandman2234]

I built a trencher many years ago, for limited use as a stumpgrinder. I welded hard surface Stellite rods across the face of each blade and then ground them sharp with a 9" angle grinder. The blades are 1/2 x 3" flatbar, so are a long way from normal blades. There has been no noticable wear on the blades, but they will still bent when they strike something unmovable. I have considered blades on the mower for the same operation, due to the amount of sand in my yard. The cheapness of the metal in the blades is the reason for fast wear. Before everything was built in china, this wasn't as much of a problem.
     If I were going to weld them up, 6011 would be my last choice. Too much work for not enough results.  A 7018 would be stonger, but hard surfacing rods will last longer than any of them. They are made for welding things that drag all the time.
  The biggest problem is the rod eating away at the edge while you weld it. Takes some fancy welding to get it close, and a lot of grinding to get it sharpe.
     David from jax

[getoverit]

Years ago, we had the same problem with a bush hog mower that was constantly needing new blades. One of my Uncles came up with the idea to weld on pieces of spring steel to the blades, and it almost ended our need for new blades. We notched the blades with a torch, making the "notch" anout 6" long and 2" deep, then welded the spring steel (came from leaf springs from a heavy truck) to the leading edge of the blade in the place where we had cut out the notches.  They last forever without the need for sharpening or replacing.

The spring steel was about a half inch thick and was about a 2" x 6" piece.

Maybe this is something you could try... worked for us

[submarinesailor]

A buddy of mine did the same thing on several Gravely blades – welding about 4" of tool steel to the ends of the blade.  Works great, but a little hard to sharpen.

Bruce/subsailor

[Modat22]

I've got some 36 inch long pieces of hardened drill rod I use to make lathe tools out in the shed. I could weld that to my blades. Plus with the rounded rod would let me get full weld penetration. Might be a bear to grind an edge on it though and dangerous if it breaks loose.

[Reddog]

Another rod we have used is Stoddy 33. Seems to hold up well. You can put most hard surfacing rods on with a torch. Nock off the flux, use a cardorizing flame. The weld will not look good but when you grind away the surface the sub material will be. For a brushhog the spring steel thing sounds pretty good. The drill rod will be pretty annealed by the time you get done welding it. were aas the spring steel you will be far enough away from the cutting edge it will still be hardened. Just my .02

[getoverit]

I went out to the field where we store equipment today and had a look under the bush hog mower, and lo and behold look what I found




These were welded on by my uncle Bill, who died in 1982. I have used this mower regularly every year to keep down the weeds and grass on oour property (if that gives you any idea on how long spring steel will last). These blades still have a pretty decent edge on them too. The cutting edge is on the top in this picture.