Nakedanvil - Grant Sarver Posted June 9, 2009 Share Posted June 9, 2009 (edited) I’m going to expand on that heavy welding thing a little for those who don’t understand it as well as they would like to. Weld stresses are mostly caused by shrinkage. The weld goes in hot and shrinks in relation to the cold plate being welded. If you tack two plates together to form an inverted “T” and weld one side you know it will “pull” towards the weld. It does so because the weld shrinks as it cools. Rule of thumb is it takes THREE times as much weld on the other side to pull it back. Now that balances the stresses, but they are still there. The two other legs will bend up and now you got a mess. Skipping back and forth from one side to the other helps but the stresses are still there. Most of the things we fabricate don’t mater that much. In thick plate fabrication the stresses go up exponentially. As I mentioned, most heavy plate fabrication gets stress relieved. The small distortion we get with thinner materials actually relieves the strain to some extent (or maybe more correctly allows it to spread out). Why are multi-pass welds bad, you ask? (And well you should!). each pass shrinks after it’s laid down. As you get to the outer passes they are going in hot and shrinking far from the other side creating tremendous stresses. Why is one pass better? Let’s take that Bechtel weld for example. We might have 2” plate butt jointed with a “U” shaped prep on the joint. The plates would be gapped about 1/16” (we often used welders clear covers for spacers so we could break them out easy). Now the joint is tacked up well and we would start welding at the bottom working up in one pass. As we welded we kept a “keyhole” open in the bottom (backside) of the joint. And we welded all the way to the top. So why would that have less stress? Well, because we didn’t have very much imbalance in heat front-to-back. While the weld is being made on one side, if you went around to the other side you’d see two things: a perfect weld bead made from the front and you’d see that the plate in the area of the weld progress was red hot for almost two inches wide! O.K. so now we have near equal heat on both sides so both sides shrink together creating very little stress. Gotta hand it to the guy who figured that out. Edited June 9, 2009 by nakedanvil Link to comment Share on other sites More sharing options...
Dodge Posted June 9, 2009 Share Posted June 9, 2009 Originally Posted by Dodge View Post We typically preheated anything over 1.5" plate. We were welding them to 5/16" - 1/8" thick light pole shafts. Generally 150 degrees f for 1.5"+ to 1.75". 1.75"+ to 3" plate was 225 degrees f, IIRC.What kind of amperage max did you have on those welders? Mine is 200amp. I really wish I had something like 250 at a minimum, but 300+ would have been even better. Of course my miller dynasty has a host of other neat features that can get compromised when you go to some of the higher amp welders which don't have those features. Also price is a feature because these welders quickly go into the $5,000.00 + range. Typically, Miller DeltaWeld 450 amp This perhaps should be in the welding section but.... Nakedanvil, there are indeed applications where multipass welds are required. We welded traffic lighting standards with uneven fillet welds of for example 3/8" x 3/4". Even with .045" wire this would be impossible in one pass and still give a proper concave contour prescribe by our specs. Largest weld I remember laying was something like 5/8" x 1" with a bevel and back-up ring. Probably had as many as a dozen or more passes. This was a double shaft thickness of 1/2" with a 13" diameter to a 3" thick base plate. The base plate would have been already pre-heated to 225 degrees. Any initial shrinkage would have been over come by the next succeeding passes. By the time the last pass was layed, you could nearly light a cigarette off it It was also my understanding that the grain structure would be spread throughout the weld bead on such a single pass if one were possible. Smaller grain;stronger weld. Hence, one of our many other specs; No single pass fillet over 5/16". IMMV but that is how the majority of traffic signal and lighting, and power transmission structures around the US and Canada, as well as many countries around the world are welded. Link to comment Share on other sites More sharing options...
Avadon Posted June 9, 2009 Author Share Posted June 9, 2009 Typically, Miller DeltaWeld 450 amp This perhaps should be in the welding section but.... Nakedanvil, there are indeed applications where multipass welds are required. We welded traffic lighting standards with uneven fillet welds of for example 3/8" x 3/4". Even with .045" wire this would be impossible in one pass and still give a proper concave contour prescribe by our specs. Largest weld I remember laying was something like 5/8" x 1" with a bevel and back-up ring. Probably had as many as a dozen or more passes. This was a double shaft thickness of 1/2" with a 13" diameter to a 3" thick base plate. The base plate would have been already pre-heated to 225 degrees. Any initial shrinkage would have been over come by the next succeeding passes. By the time the last pass was layed, you could nearly light a cigarette off it It was also my understanding that the grain structure would be spread throughout the weld bead on such a single pass if one were possible. Smaller grain;stronger weld. Hence, one of our many other specs; No single pass fillet over 5/16". IMMV but that is how the majority of traffic signal and lighting, and power transmission structures around the US and Canada, as well as many countries around the world are welded. Great! Now you made me ---> <--- Green with jealousy. I would love a 450Amp machine. Yah know when I bought my welder I never thought i'd get into welding the big thick stuff. Turns out I love to weld the thick stuff. Must be due to being dropped on my head as a small child lol. Your right, with the pre-heating and welding passes my anvil stand in many places was hot enough to almost like a ciggie off of. In fact I took a video of me spitting on one of the cross members and it was so hot the spit just beaded on the surface like a scalding hot frying pan. I would think a lot of that heat would normalize a lot of the stresses. Of course as naked anvil said, were not building nuclear submarines here. I think a bit of my welding was overkill, but I didn't mind laying some extra beads. I definitely will bolt my beast down once I find out where I want it. Link to comment Share on other sites More sharing options...
Dodge Posted June 9, 2009 Share Posted June 9, 2009 Great! Now you made me ---> <--- Green with jealousy. I would love a 450Amp machine. I should be jealous. The 450s were just what the company I worked for had. My home MIG welder is just a 150 amp, and my stick is a whopping 225 amps ;) Link to comment Share on other sites More sharing options...
arftist Posted June 9, 2009 Share Posted June 9, 2009 Dodge; you guys are not talking apples and oranges, more like grapes and coconuts. There is a whale of a difference between .045 wire and 1/4" rods. The same rules just don't apply. By the way , I have welded 1"x1" fillets on heavy lifting booms with .045 flux core. One pass. Link to comment Share on other sites More sharing options...
Frosty Posted June 9, 2009 Share Posted June 9, 2009 Welding luminairs is spec'd by engineers and deviation isn't allowed for good reasons. The last time a contractor made a single pass weld on a high tower pole to base where multiple passes were called for a 140' high tower fell across the busiest highway in Alaska. To be fair, there were pre-heat specs they disregarded too. Fortunately it didn't land on anyone and nobody hit it but it was a BAD thing. The incident resulted in inspections of all the high tower and luminair poles welded by this contractor and there were stress cracks developing in virtually every single high tower they welded and around 30% of the luminair poles. The contractor went bankrupt and the state of AK was left on the hook for millions replacing the high towers and luminairs. Welding is NOT a one process fits all trade. Not that anyone here is saying that but someone who doesn't know welding may think so. Frosty Link to comment Share on other sites More sharing options...
Dodge Posted June 10, 2009 Share Posted June 10, 2009 Well said Frosty. BTW State of Alaska was one our customers. Hope it wasn't our product that failed :o Link to comment Share on other sites More sharing options...
arftist Posted June 10, 2009 Share Posted June 10, 2009 Yes Frosty, Well said, indeed. Link to comment Share on other sites More sharing options...
Frosty Posted June 10, 2009 Share Posted June 10, 2009 Not likely Dodge, the installing contractor screwed them up. Do you send stuff to Anchorage? I may have helped put a couple up, I know I've taken a couple down. . . With a grader. Frosty Link to comment Share on other sites More sharing options...
Avadon Posted June 13, 2009 Author Share Posted June 13, 2009 FINALLY, RIGHT!! Here is a little info about the Stand I made for Nimba's Gladiator. Death Industries Anvil stand: Weight: 265lb (With anvil ~715lb) Thickness of bed: 2" Width: 10.75" Length: 20" Legs: 5" x 3" x .025" rectangular tubing Legs: 25dgs from vertical, 30dgs apart in front. Anvil stops: 1" Sq Rod with qty 4, 1/2X20NF Grade 8 Bolts. 3 Grade 5, 1/2x20NF bolts for filling hollow legs and cross members with sand for deadening ring. Parting Bolt: 1/2x20NF Grade 8 bolt underneath breaks anvil from calk/adhesive bond. Welds: Stand is pre-heated and multi-pass welds are used on every joint. Steel gussets brace cross-members. For info about the prying bolt and caulking questions see this threadhttp://www.iforgeiron.com/forum/f83/anvil-caulking-question-12493/ Gladiator Anvil Specifications: Tip to Tip Length: 39 inches / 99 cm. Height: 13 inches / 33 cm. Face Width: 7 inches / 17.8 cm. Base Width: 10 inches / 25.4 cm. Base Length: 15 inches / 38.1 cm. Hardie Hole: 1 inch / 2.54 cm. Pritchel Hole: 7/8 inch / 2.2 cm. Weight: 450 lbs. / 204 kgs. Link to comment Share on other sites More sharing options...
Avadon Posted June 13, 2009 Author Share Posted June 13, 2009 (edited) Here are a few other pics of the cross members and bracing. The roses engraved on the 3 fasteners and the jacking implement I made. I have a need to be able to move my anvil so I created some wood bracing with some metal rails that keep the anvil and stand balanced side to side. Once I get it lifted up I can place the two steel jacks I welded up underneath it. Then I can move my pallet jack fully underneath the feet. Once I got up there it's safe to move. If I make more for sale or for myself I will probably include some other jacking ports. The anvil locks into the stand so incredibly strong that for all intensive purposes it becomes one piece. It is deceptively heavy, trying to lift the anvil from the heel seems like a doable proposition because it's placed near your hands but no matter how much force you exert it does not budge a bit. Of course that disc that just slipped in your back will move lol. Edited June 13, 2009 by Avadon Link to comment Share on other sites More sharing options...
Avadon Posted June 13, 2009 Author Share Posted June 13, 2009 Looks like the rest of the pics didn't make it. You can see that initially I just jack it up using the lumber with the metal rails. Once in place I throw the jacks under. Then I take the pallet jack down and place it under the rear feet and throw the bar under the front foot. Then its good to travel. That is a micro pallete jack rated at 1000lb, so I take care with this 700lb item. Even though it's no where near as big as the 700lb band saw behind it, it is deceivingly heavy and if it tips dangerously or miscarried when it is moved, it could go over. Link to comment Share on other sites More sharing options...
philip in china Posted June 13, 2009 Share Posted June 13, 2009 Little pallet truck like that is so useful, Link to comment Share on other sites More sharing options...
Brian D Posted June 13, 2009 Share Posted June 13, 2009 Nice looking stand. Nice anvil too. Good job! Link to comment Share on other sites More sharing options...
Avadon Posted June 13, 2009 Author Share Posted June 13, 2009 Thanks. Yep those little pallet jacks are almost a must, even for a small shop. They make jacking and moving things so helpful. Best 250$ I spent at grizzly tool. :) Link to comment Share on other sites More sharing options...
Frosty Posted June 13, 2009 Share Posted June 13, 2009 That's almost too pretty to use! I picked up an engine hoist at a yard sale summer before last and it's a real back saver. Very well done, she's a beauty. Frosty Link to comment Share on other sites More sharing options...
Avadon Posted June 13, 2009 Author Share Posted June 13, 2009 Thanks Frosty, got most of your ideas on there, as well as a few others from people here on this forum. Link to comment Share on other sites More sharing options...
arftist Posted June 13, 2009 Share Posted June 13, 2009 Well, you certainly put some effort in that. NICE JOB! I especialy like the lower brace conecting the three legs. That should really stiffen things up. Link to comment Share on other sites More sharing options...
tat2dgrizz Posted June 13, 2009 Share Posted June 13, 2009 Excellent job Avadon, as far as anvil stands go, that has everything and more. t2g Link to comment Share on other sites More sharing options...
Fe-Wood Posted June 13, 2009 Share Posted June 13, 2009 Super Job!! That should last a while:) I long for a pallet jack..... Link to comment Share on other sites More sharing options...
Avadon Posted June 13, 2009 Author Share Posted June 13, 2009 Thanks tat2dgrizz and fe-wood. I should have probably gotten the legs a little closer to vertical. Like 20dgs vs 25dgs. But I held them up at 20dgs and for some reason that seemed kinda scary to me. Like it might be easy to easy for it to tip over. They probably could be at 20dgs or even 15 without any problem, especially if you've anchored it down. Link to comment Share on other sites More sharing options...
Dragons lair Posted June 14, 2009 Share Posted June 14, 2009 If you anchor it down the legs could be streight and it couldn't tip ken Link to comment Share on other sites More sharing options...
Avadon Posted June 15, 2009 Author Share Posted June 15, 2009 I didn't see these videos till just now.. Hofi's setup. Really good looking equipment as well. YouTube - hofi anvil introduction youtubeversion2 Link to comment Share on other sites More sharing options...
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