Hard surfacing

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Since I live out in the Country, I tend to mow a lot of rocks when cutting the grass up and down the drivway.  This tends to kick the ____ out of the edge of the lawn mower blades.  I have a 48" ride'em. That has 3 16.5" blades on it.  I replaced the old ones with new. and since the old ones now look like a piece of 1/4" flat bar on both ends.  (It's not quite that bad, there is still a slight taper, but the edge is defiantly rounded off).  So I thought I'd try a little experiment.  Has anyone ever used a Rod called "ARCTEC 63 Hardcro"?  It is used for hard surfacing on in-feed rolls for De-barkers.       I tried to weld a bead down the (What use to be) the sharp side of the lawn mower blade.  But even with a really low heat setting, I was unable to run one smooth bead down the edge of the blade.  All I succeeded in doing was making an ugly bead with gouges in it.  Air bubbles, and blow-en away edges.  (Hope that explains it. I don't have a camera)  I did not want to rebuild the edge of the blade I just wanted to put a coating on top.   It can only be machined by grinding, after it has been applied.  I was hoping to extend the life of the blades when they come into contact with the rocks.      Since I was trying to run down the edge of the blade, I laid the blade on a board before welding.  Bad idea I think.  Lots of wood smoke and burning holes in the plywood.  Afterwords I thought about running a bead down the edge with a piece of brass plate under it.  Do you think this would stop the metal from blowing out when I run the bead?   Open to any suggestions anyone might have.  Thanks   Packrat,  (The guy who never throws anything out)Lincoln 225 AC/DC, Hobart 140 Mig. Oxy/propane Victor torch.(2) Makita 5" angle grinders  one with zip disk, 14" chop saw.  and just about every other tool you can think of. Whoever has the most toys when he die's ..... Wins!
Reply:I hardface my ride-on mower blades. The rod is PH600. I use 3.2mm rod & approx 110A. You will need to sharpen a edge after you hardface so just keep building it up so you have material to grind off. Watch your blade balance & weld quality. PS The harder you get the more likely it is that the blade will chip so get a rod that isn't too hard. (I don't know the rod you have got but it sounds a similar type of rod to mine)James
Reply:Originally posted by grillonz  Watch your blade balance & weld quality.
Reply:Would it be a good idea to maybe build up with a softer rod?  Like 7018 or something first?  Then make a pass with the hard cro. I have been checking the balance after each weld, but especially when grinding the finished edge back on.  Maybe it would be cheaper to get new blades, but the one's I've already dented up are still in usable shape.  I didn't want to build up to much hard face with multiple passes .... If I do that, your right, they will chip apart easier than a dent.  hmmm..... I'm sure if I keep cutting the same rocks sooner or later they gotta quit growing.  LOLLincoln 225 AC/DC, Hobart 140 Mig. Oxy/propane Victor torch.(2) Makita 5" angle grinders  one with zip disk, 14" chop saw.  and just about every other tool you can think of. Whoever has the most toys when he die's ..... Wins!
Reply:Originally posted by Packrat hmmm..... I'm sure if I keep cutting the same rocks sooner or later they gotta quit growing.  LOL
Reply:I checked out Vipermanz websites.  Thanks for the tip, but they didn't help.  I have a Sears Craftsman, and none of the blades listed on any of the sites carry that brand or the size, and type I need.    I couldn't find any parts on the Sears website either. ???      So now I'm just gonna phone them.Lincoln 225 AC/DC, Hobart 140 Mig. Oxy/propane Victor torch.(2) Makita 5" angle grinders  one with zip disk, 14" chop saw.  and just about every other tool you can think of. Whoever has the most toys when he die's ..... Wins!
Reply:I would think welding on a high carbon blade might cause cracking and pieces to fly off at tremendous speeds.  Could be a hazard.Get it hot and hit it hard...
Reply:if you are welding steel and need to get a thin section, clamp a piece of 1/4 inch thick copper busbar under the edge of the piece you are welding onto. the copper is a great heat and electricity conductor and you run your bead right along the edge of the steel. then when cooled the steel will break away from it fairly easily, mybe needin a hammer tap or so if its nit broken away by itself when cooled. brass and aluminum might or might not work but I have always had good luck with copper on MIG work. its also great for letting you fillup holes like when somebody drilled a blooper where they shouldnt have and you have to weld it shut but dont want to warp everything and make another booger there. even works fine on galvanized thin steel.balancing the blade is a must after grinding the basic edges on the welds.the harder the material the more critical is the angle on the edge. harder materials will chip more easily co make sure they have LESS acute angle when sharpened. a harder blade that stays sharp will cut well with a less acute angle than a softer material that dulls faster along the thin edge. If it gets ground too thin - the hard material will chip off quickly even when hit with small stones etc.
Reply:packrat,   You're probably doing this for a sense of accomplishment and the learning experience. Forget about saving money- you won't come out ahead. I've gone down the same road with bush hog blades and finally wound up taking them to a professional welderwho did a beautiful job for 1/3 the cost of new blades.Hardfacing is more exacting that you might think-many things toconsider including the effect of the heat on the original blade edge. Even with the hardfacing they still chip and crack whenkissing rocks.    I'm sure you can find blades for that mower. follow up on someof the url's in earlier posts. It's always better to have an extraset or two of blades anyway.   Whichever way you decide to go, best of luck and keep up posted.Don
Reply:You're probably doing this for a sense of accomplishment and the learning experience.
Reply:The copper plates I use most are links or cutdown busbar pieces recovered from scrapped-out electrical gear. most electrical contractors get this stuff by way of having to remove old switchgear when they do the replacment or upgrade work. they get very good $ for scrap copper so they usually clean it out before sending the steel to the recycling yard. many times the copper goes home in lunchboxes long before it ever gets back to the shop. call up a few electrical contractors and see if they have any small pieces they would sell for reasonable price. they are not supposed to re-use most of it so if its used, dont pay new price. easiest to find is around 1/4 by 2 inches, up to 4 inch width, cut to length you find handy. 1/4 is standard thickness, you can find a little bit thicker but most larger bars are simply made up of multiple runs of 1/4 inch becasue it cen be bent without breaking when soft. larger sizes are more costly to bend smoothly even when annealed. thinner than 3/16 or 1/8 is no good for heat sink- not enough mass and thermal transfer rate to keep parts cool but OK for backing for sheetmetal to weld up small holes ( I once saw an old-style copper penny used for this - and it worked fine).if you want some real practice -   try TIG-ing the holes closed in them with some copper wire for filler. lotsa fun to set up the heatsinking and a race with the heat properties.  that job will split the men from the boys.