iron quake Posted February 25, 2012 Share Posted February 25, 2012 I posted this in the heat treating section and got views but no replys. Do I need to remove the old post?I’m about to start making tooling, for the 100 lb LG hammer, I just rebuilt and put a brake on. Thanks to Sid at LG, Peacock, and McBruce by the way for your help in this endeavor. So my question is this; I’m going to make most of the tooling; swage blocks, fullers, v blocks and the like, either with spring arms or side bars to attach to the bottom die holding fixture I just machined. Most of the tools will be made of 4140 and sent out for professional heat treating, in the mid 40 RC range. I’ll try to harden and temper some of the simple, smaller tools myself, in quenching oil or canola. So, can I weld the mild steel spring arms or attachment bars on after heat treatment or should they be attached first? I’m not so much worried about breaking tools and having to remake or repair them, as having them fail and come shooting out and killing me BTW. Quote Link to comment Share on other sites More sharing options...
HWooldridge Posted February 25, 2012 Share Posted February 25, 2012 I would not bother with hardening anything if you are not making high production tools. Some of my best swages are made from mild steel and have held up for years. Hardening helps prevent scale damage to a degree but is not a huge necessity when forging hot iron and can result in those shooting missiles you mentioned if not done properly. Quote Link to comment Share on other sites More sharing options...
Sam Salvati Posted February 25, 2012 Share Posted February 25, 2012 I am with Hollis, mild steel is great for powerhammer tools, cheap and doesn't mark up your dies, if you need more toughness too water quench it. Quote Link to comment Share on other sites More sharing options...
swedefiddle Posted February 25, 2012 Share Posted February 25, 2012 Good Morning, I bought some crops of 2 1/2"-T1. I have been using the Dies I made from them for over 15 years. I never Heat Treated them and they have never cracked or chipped. T-1 is used for making excavator/back-hoe buckets. Neil Quote Link to comment Share on other sites More sharing options...
Stormcrow Posted February 25, 2012 Share Posted February 25, 2012 I think you can go either way. The dies for my homebrewed power hammer are made from 4140 welded to mild steel base plates. I heat treated the dies myself first, then the next day or so pre-heated them to 400 degrees Fahrenheit for an hour, welded them, then post heated again at 400 for an hour. No problems from them at all. If you're going to weld on 4140, I've seen it highly recommneded that you do the pre and post heat to avoid cracking. I'd do it whether you are heat treating or not and whether or not you weld before heat treatment or afterwards. Quote Link to comment Share on other sites More sharing options...
peacock Posted February 25, 2012 Share Posted February 25, 2012 I use drops from a leaf spring shop. Never heat treat, and have made 1000's of acorns with no diffent between the last ones and the first ones. You are after tough not hard. 4340 as forged, is really good if you have acess to some of that Quote Link to comment Share on other sites More sharing options...
InFire Posted February 25, 2012 Share Posted February 25, 2012 I agree with the general consensus. Do not heat treat power hammer tooling. It’s meant to work HOT metal, and it makes high speed UFO’s flying out from between your dies a lot less likely. Find steel you have easy access to and learn how to forge it and what processes it functions best at. The tools that require a higher quality steel such as a hack or the dog bone type cutoff you saw in Clifton Ralph’s tapes still only require toughness. Try locating some S or H series steel for any thin section tools that will have prolong contact with hot steel and make several of each. If the one you’re using is getting too hot, lay it aside and grab another. Punches are another example where it makes sense to use a good quality steel. I’ve used high speed cutting tools from lathes for punches and they will have little or no deformation after several punchings. I suppose there is some process that might require tooling to be heat treated but to date I don’t have any tooling that goes between the dies of a power hammer that’s been heat treated. Oops, I think I need to make an exception with the S and H series steel. Simply by heating it to a forging temp and letting them cool will toughen the steel. Forging and using air hardening steels does require some practice to get the best results. Again, I stress toughness not hardness when it comes to power hammer tooling. You’re also going to have to learn to weld to any type of steel that you use. Each type will need to be stress relieved after welding and often you will need to pre-heat to get the best results. The best way to avoid the problems with welding is to forge the tool in one piece if possible. Reduces the possibility of stress cracks and you get to spend more time using your new hammer. Quote Link to comment Share on other sites More sharing options...
JNewman Posted February 25, 2012 Share Posted February 25, 2012 I am going to disagree with most of the above advise. While mild steel will work for simple short run tooling on smaller hammers, higher carbon or alloy steels will last much longer. If you are using an alloy steel like 4340 or 4140 you SHOULD be heat treating it. I DO AGREE IT SHOULD NOT BE TOO HARD. But if you are not heat treating it you are not getting what you paid for in the alloy steel. I have a simple tool I made a while back to flatten the end of a 5/8 bar that is upset to 13/16" down to 1/4" thick. I machined it out of 4140 and never got around to heat treating it. I used it for a run of 50 pieces, at the end of the 50 pieces it was dished out by over 1/32" , so my finished parts were 9/32" thick instead of 1/4" For 4140 and 4340 lately I have been using a simple heat treatment that Forgemaster posted on here. Oil quench and then reheat to the point where the oil flashes off. The autoignition temperature of mineral oil is up around 700 degrees which is a dark blue going by temper colours. I would not temper your dies this soft but it works well for a lot of tooling if you do not have a temperature controlled furnace. H13 will actually work much better if you temper it after air hardening at about 1000 degrees which is a very dull red that you can only see if you hold the work in the shadows. Quote Link to comment Share on other sites More sharing options...
JNewman Posted February 25, 2012 Share Posted February 25, 2012 I’ve used high speed cutting tools from lathes for punches and they will have little or no deformation after several punchings. I suppose there is some process that might require tooling to be heat treated but to date I don’t have any tooling that goes between the dies of a power hammer that’s been heat treated. Those high speed lathe tools have all been heat treated and are VERY hard. Grant had mentioned once that he had a friend who had an employee get killed with HSS tooling exploding. Read post 38 http://www.iforgeiron.com/topic/12911-h13-tool-steel-heat-treating-tool-making/page__st__20 Quote Link to comment Share on other sites More sharing options...
JNewman Posted February 25, 2012 Share Posted February 25, 2012 To the original question. I have welded handles and springs on both before and after heat treatment with preheating the tool. I almost always find the HANDLE or SPRING breaks right beside the weld. Drawing out the handle or spring as mentioned above is a good solution. I have also found post heating near the weld and longitudinal welding beads on the spring help. If you search you will find several threads on this subject. But because the breaks are usually in the mild steel spring I don't think it makes much difference as to when you do your welding, if you choose to weld the handles on. Quote Link to comment Share on other sites More sharing options...
Fe-Wood Posted February 26, 2012 Share Posted February 26, 2012 . I have also found post heating near the weld and longitudinal welding beads on the spring help. What JNewman said- Just run a bead about 1/2" back up the center of the "handle" from the weld zone. Hard tools shatter- Quote Link to comment Share on other sites More sharing options...
forgemaster Posted February 28, 2012 Share Posted February 28, 2012 Swages we don't heat treat at all, cutting tools like hammer cutters we do heat treat, stamping tools we make them out of En36A (4317 or 17crnimo6) and just water quench them from above 800 degrees, with no tempering. I have added more on this subject in this same post in Heat treatment. Phil Quote Link to comment Share on other sites More sharing options...
iron quake Posted February 28, 2012 Author Share Posted February 28, 2012 Wow a lot of differing opinions on this. I'm going to try and get away with un heat treated 4140 and see how it holds up. If it looks like its wearing to quickly I'll heat treat it by quenching in oil and and then draw it back to mid 40 RC to get a little hardness an more toughness. I purchased some pre heat treated 4140 today and I'll try using that after forging it. I must say I don't understand the logic of forging a steel with any level of carbon and not doing the normal heat treating process after that. If you heat it up hot enough to forge it you'll be above the transformation temperature for most carbon alloys, except high temp materials like H13 at 1850F. When it cools as you forge it, its going to become hard. If you don't then temper it, don't you then have the worst condition possible? High hardness with a lot of internal stress. You get the benefit of the compressed grain structure but still with very high internal stress. Should you not then temper the material, releaving the stress and getting uniform hardness and toughness. Quote Link to comment Share on other sites More sharing options...
forgemaster Posted February 29, 2012 Share Posted February 29, 2012 You should at the least normalise after forging before using as a hammer tool, you talk of tempering your tools, are you aware that before you temper them you have to harden them. Tempering relieves the brittleness that exists after a metal is hardened. As I stated in my post above, the level or necessity of heat treatment in dictated by the end use of the tool. If you are making swages, you don't really have to heat treat them, if you are making cutting tools some kind of heat treat would be a good idea. If you are making a stamping tool it also will depend on the amount of jobs that that tool will be expected to produce, if you only need to stamp 3 or 4 jobs from it, even 10 jobs, you may be able to get away with no HT, if you need to stamp 100s well HT would be good, that also depends on the steel that you have used to manufacture your tools from. Phil Quote Link to comment Share on other sites More sharing options...
DClaville Posted March 2, 2012 Share Posted March 2, 2012 the way i have been told to make spring swages it you forge the blocks then drill a hole 18mm in each and then take a 16mm round bar and upset one end to 18,5mm on the diagonal square, but only upset a length that is about half the depth of the holes you drilled then heat up the block and hammer the cold rod in and then take a large center punch and punch all around the hole with the bar in it. the measurements are figurative and should be adapted to the size of the tools. this should hold many time longer then any weld. here is a photo that shows it donehttps://fbcdn-sphoto...7_5289629_n.jpg Photo is borrowed from Roger Lund, Sweden Quote Link to comment Share on other sites More sharing options...
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