November 14, 20214 yr Ever since I watched Scott over on the Essential Craftsman YT site make a video on how he fabricated a Burke Bar, I wanted to make one. If you don't know what a Burke Bar or what it looks like, here is the video: So I found a piece of 5/8" thick truck spring leaf and cut it to size, welded a piece of rebar to hold it for forging and hammering and then got it heated up in my brake drum coal forge: I was shocked at how easy it was to forge the pry end down and to bend the bar into the angle needed: To normalize it, I put it back into the fire and got it to a dull red heat, then just turned the blower off and let it sit. Here it is after the fire has cooled down: After grinding down the bevel for the pry end. I messed up the shape of the nail puller. And after "tempering" in my toaster oven at 500-550 for 6 hours: After cleaning and polishing with a 120 grit flap wheel: Time to move onto the handle. I found a piece of rectangular tubing; I *think* it's 1"x2"x1/8", but I'm not sure: Cut the slot, cleaned it up: Welding pics aka Splatter City! Cleaned up nicely though: Anyone who watches Scott at the EC channel will catch the reference: Those White Ox gloves are - by far - my favorite work gloves! Thanks for looking!
November 15, 20214 yr You didn't normalize, normalization is heating to above critical and letting sit in still air. You were doing a semi anneal. Did you preheat/slow cool before/after welding; or will there possibly be cracks in the HAC zone? Welding on spring and HC steels has different requirements than on mild. If the cracks have happened there is no way to recover afterwards. Seems like you are possibly getting ahead of your learning curve a bit.
November 16, 20214 yr Author This not normalizing? "To normalize it, I put it back into the fire and got it to a dull red heat, then just turned the blower off and let it sit." Dull red heat in bright sunshine, not dark. I forgot to mention: I heated the pry bar end up to 450-500 degrees for an hour and a half prior to welding. Before I use it, I plan to heat the pry bar end up in my forge, but I haven't fired it up since.
November 16, 20214 yr What I said: "normalization is heating to above critical and letting sit in still air." If it was sitting in the forge, especially if it was actually in the coals then NO that is not normalization. I anneal using my propane forge: heat the forge up, heat the workpiece up to critical; close the forge up and turn off. With coal: heat the piece up and place in an insulative medium to cool slowly---like dry wood ashes or vermiculite if a piece is small I will also heat up a piece of scrap as a heat donor to go into the medium adjacent to the small piece. To Normalize; I heat above critical and then hang in still air using rebar tie wire. Great that it was preheated; you didn't need so long a soak period; but higher carbon steels do need to be hot when welding on---you are trying to avoid the hot zone being quenched by the cold metal near it causing cracking. Slow cooling also helps---you are basically tempering it as it goes along. I know an old cowboy who broke the frame on his pickup truck; he'd weld it back together only to have it break adjacent to the weld. I told him it was a heat treated frame and he needed to do a preheat and slow cool on it and would probably end up with a softer zone around the weld but not a break.
November 17, 20214 yr Author Speaking of welding on spring steel: IMO, Scott made two mistakes when he made his Burke bar: He hardened the bar, then tempered it. Despite spending quite a bit of time discussing tempering, i don't think he tempered it to a high enough temperature. The other mistake was that he left a forging defect right at the bend of the bar; he called it a "Beauty Mark". Scott made this bar for fellow YTer Andrew Camarata - and Andrew promptly broke it. He very briefly shows the repaired bar in one of his videos and it appears it broke right at the forging defect near as I can tell. The repair? Andrew welded it right up; says it has worked fine since then (see his comments in the video in the OP. So, relevance to this thread: Everything I've read for pry bar tempering is to leave it as-is after normalizing; the failure mode should be bending, not breaking. Granted my normalizing procedure may not have hot enough or long enough to cool or whatever. This steel has never been hardened or quenched since it left the factory; it's been brought to forging temps, not once but twice and it sat in a "tempering" oven for 6-8 hours total. I plan to heat it up one more time to at least a dark blue temp before I put it into any heavy use. If it breaks, so be it; I've got tons of leaf springs hanging around here.
November 17, 20214 yr The issue is not that it's easily replaceable; but that it may injure the user if it fails. Injuries tend to be MUCH more costly than tool replacements! Annealing rather than normalizing is probably too soft for effective use. Leaving it in the firepot with the air turned off; if it is covered with coke or charcoal; is annealing. Jargon is important as it lets a group of people make fine distinctions quickly and easily. For example: if I say "critical temperature" people all over the world involved with working steel know *exactly* what temp I am referring to---doesn't matter if they are using degC, degF or degK; Critical Temp is Critical Temp. Likewise annealing, normalization, quenching all have specific meanings.
November 17, 20214 yr Alas, Thomas, you have just violated your own precept. This: On 11/15/2021 at 7:19 PM, ThomasPowers said: you are basically tempering it as it goes along is not correct. Tempering is a process done to hardened steel, to change some of the quenched martensite into tempered martensite and thereby reduce hardness and increase toughness. If a piece of steel has not been hardened (such as a piece that has been preheated, welded, and allowed to cool without quenching), then there is no quenched martensite to convert. Allowing the piece to cool slowly from incandescent to below critical temperature ensures that martensite doesn't form at all.
November 17, 20214 yr Martensite can form at above tempering temps depending on the alloys; if the material is martensite and is at a tempering temp then what happens? (Ms temp can be 500 degC) Anyway it keeps a brittle zone and/or cracking from forming in the HAZ.
November 18, 20214 yr Author Any ideas on all the welding splatter? It doesn't happen very often to me, but it's always aggravating.
November 18, 20214 yr Mig welding with CO2 will do that, just part of the process. Flux core produces a lot of splatter too. But you want to keep the tip in tight and avoid too much stick out.
November 18, 20214 yr Yes, there's still spatter, but the spray keeps it from sticking. I'm still not entirely sure how it works, but I think it's some combination of a lubricating effect (that keeps the spatter moving while it cools) and an insulating effect (that helps keep the spatter from welding itself to the workpiece's surface). If you're using flux core, it also makes the slag and smoke residue easier to remove. There are a bunch of different varieties with a variety of different characteristics. The stuff I'm currently using (mainly because I got a killer deal on it at the industrial surplus place) is definitely a "use only in well-ventilated workspace" solvent-based product, but it does have the advantage of being paintable. Water-based varieties are a bit friendlier, but increase the risks of hydrogen embrittlement and rusting.
November 18, 20214 yr Anti spatter boils under red hot dingle berries so they ride the vapor barrier till they're too cool to stick before they actually touch the steel, torch tip etc. Frosty The Lucky.
November 18, 20214 yr Like spit on a griddle. That is what I was told in a welding class 50 years ago when I asked why anti spatter spray didn't effect the weld. He said It boils away clean before the metal melts. Frosty The Lucky.
November 18, 20214 yr John; are you going to charge up a Leyden Jar and try out the Leyden-Frosty effect at Q-S next fall?
November 18, 20214 yr Are you wondering if I get steamed enough I'll keep . . . SOMEONE from touching the ground till I cool off? I suppose spectators might stand around saying, "ARC ARC ARC." Not a chance, I don't want to get arrested for battery. Frosty The Lucky.
November 18, 20214 yr (Cue dachshunds flying box kites into thunder storms! They will really get a charge out of it!)
November 19, 20214 yr Cute dachshunds doing anything but their "business." They're well grounded dogs, that's the long and short of it. Frosty The Lucky.
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