Joel OF Posted January 28, 2018 Share Posted January 28, 2018 Hi folks, I'm after some input regarding power hammer spring swages. I've not had my power hammer very long but recently made a spring swage that turns 40mm (1, 1/2") solid square into 28mm (1" ish) round. I need to use it in the middle of the bar to round up a 75mm (3") section. I've been doing a bit of experimenting with it & found the bar is twisting during the process so that the square sections either side of the round portion are out of alignment. Thinking back I know I made the mistake of rotating the back continuously in one direction & that is likely to have made the problem worse, but I'm wondering if this twisting is a common problem in any case? I don't mind having to do a bit of corrective twisting, I'd just like to know that this is something other folks encounter too. I have attached before & after pictures to help explain what I mean. I also neatened up the shoulders with a file after twisting. Quote Link to comment Share on other sites More sharing options...
WayneCoeArtistBlacksmith Posted January 28, 2018 Share Posted January 28, 2018 I would used a Kiss Block rather than the spring swage. Make a 3/4" block and weld it to a piece of angle iron about an inch wide. Clamp it onto the bottom die with a C clamp. Draw down to 1" square first then forge to round. You might want to use about a 1/2" spring fuller to isolate the mass and to get a smoother transition. Let me know if I can help you. Wayne Quote Link to comment Share on other sites More sharing options...
Joel OF Posted January 28, 2018 Author Share Posted January 28, 2018 My terminology isn't very good as I'm self taught - I'm assuming a Kiss Block is a generic term for a type of block? I can see the logic of forging to square before rounding up, but the result I have in my head from your description wouldn't give me a 1" square section that's centered, it would be bias towards one side of the bar, and I need the rounded up section to be centered. I guess I'm misunderstanding your description? The only way I can picture forging to square first (centred in the bar) is with another spring fuller that's got plain flat faces. Ideally I'd like to stick to just using the spring fuller I already have as I can forge that section round in 1 heat & the filing only took about a minute. However if adding extra steps are a better guarentee of straightness, then they're very welcome & appreciated! Quote Link to comment Share on other sites More sharing options...
Jim Coke Posted January 28, 2018 Share Posted January 28, 2018 Greetings Joel, IMHO. The metal twist is established on the first compression of the spring fuller. You might try a butcher to form the edge first. I ran across this using dies on my fly press. My solution was to use a cut off disc to form the edge instead of a butcher . In your case the cut should have about a 3/16 deep grove . Give it a try it might just work for you. Forge on and make beautiful things Jim Quote Link to comment Share on other sites More sharing options...
anvil Posted January 28, 2018 Share Posted January 28, 2018 I'm having trouble with my pics. So this may be a double post. Iron has a natural tendency to twist. I was told once if you support a 20' length of 1" square flat on the ends, the middle will be on the diamond. Seems I tried it and it's true. Just align the two square crossections. Along with my set of spring fullers made from coil spring and my 25# lil giant, the above tools did this candelabra. Ok, if it's going g to twist, go for it! Notice the round twist on the 1" round. I believe this was 1-1/2"(maybe 2") square forged down to 1" round. Quote Link to comment Share on other sites More sharing options...
Judson Yaggy Posted January 29, 2018 Share Posted January 29, 2018 No matter how careful you are making a tool, something will be out of alignment. Especially after you smack the tool a few times. Also, your dominant hand/side will fight your eyes when trying to put a work piece square to an anvil or power hammer. (looks like Joel is left handed from the way he set up his PH dies.) Drag from tooling and resistance of the work are inevitable, they will twist or bend things a little no matter how practiced you are. I would have brought Joel's example to octagonal before going into a round swage, I find it's easier to control things with flat planes to look at while working. Or perhaps I should say I can see when something is out of wack earlier with flats over rounds. Quote Link to comment Share on other sites More sharing options...
WayneCoeArtistBlacksmith Posted January 29, 2018 Share Posted January 29, 2018 Joel, you are correct there. I posted without thinking through what I was saying. When I have done that I used combination dies where the narrow portion is only about 1" wide. I put the kiss block on the wider portion. A kiss block is a piece that is clamped in place to keep the top die from coming past that point. combination dies are shaped like this: -- Quote Link to comment Share on other sites More sharing options...
Joel OF Posted January 29, 2018 Author Share Posted January 29, 2018 Thanks for the input folks. 7 hours ago, WayneCoeArtistBlacksmith said: A kiss block is a piece that is clamped in place to keep the top die from coming past that point. Ah, now I get ya. 7 hours ago, Judson Yaggy said: Looks like Joel is left handed from the way he set up his PH dies. Haha nope, just another quirk of being self taught & setting up my shop in way that feels comfortable. I think I'll stick to my current method & suffer the consequences of the twisting as it seems that to avoid it I've got to add in another stage or two, and doing so will take me just as long as it does to twist it back. One thing I like about using the spring swage from the start is that I'm guarenteed that the rounded up section is centralized with even shoulders all around. This part is the top hinge in a gate so the eveness of it is critical. My mind's been put at ease hearing that the twisting is a natural result of this tooling method, rather than me doing the method badly. I suppose that a spring swage doesn't close paralell, it closes at a slight arc & that'll affect the outcome. Same difference between leg vises & engineers' bench vises. Maybe in the future I should make a guillotine jig setup for my power hammer so that interchangeable dies will close straight. P.S nice transitions on your candleabra @anvil Quote Link to comment Share on other sites More sharing options...
anvil Posted January 29, 2018 Share Posted January 29, 2018 Here's another thought, altho you might be aware of it. Forge your 1" round to about 6" length, then forge weld onto this the length of 1" round you need. A forge weld is quicker than a long drawn out experience. As for twist, I always check for twist. Even on say half square pickets that only get champfer edges. No matter how good your hammer control, there is always some twist. Clamp the picket in your post vice, then use two short pieces of 1"angle iron and line up the top edges with my twisting wrench. Quote Link to comment Share on other sites More sharing options...
anvil Posted January 29, 2018 Share Posted January 29, 2018 The devil is in the details, so more explanation. The two dies with multiple holes are for forging tenon's. Each is a 1/16" smaller from 5/8" to 5/16". This pretty much guarantees parallel closure. Alas, the reason my 1" die is sprung is because I did not make larger tools to handle the larger material. Thus, not even close to parallel, and far more work under the hammer. I've since added the proper tools, and can go from 2" to 1" in 1/4" increments. Much easier now. No need for going square- octogon- round. However with a bigger air hammer, which I don't have, I like the idea of separating the area to be drawn out and using a kiss block,flat dies, and forging square- octogon- round. Sweet! Thanks for the idea Quote Link to comment Share on other sites More sharing options...
Joel OF Posted January 29, 2018 Author Share Posted January 29, 2018 24 minutes ago, anvil said: Here's another thought, altho you might be aware of it. Forge your 1" round to about 6" length, then forge weld onto this the length of 1" round you need. A forge weld is quicker than a long drawn out experience. As for twist, I always check for twist. Even on say half square pickets that only get champfer edges. No matter how good your hammer control, there is always some twist. Clamp the picket in your post vice, then use two short pieces of 1"angle iron and line up the top edges with my twisting wrench. Sorry I'm not following you at all, but that may be the wine. I don't start with 1" round bar. My idea for making sure the two square sections of bar either side of the short round section are twisted back straight was going to be: Clamp flat bar to at least 1 face at a time & span it across the transition area. If the bar lays flat on both faces either side of the transition then it's twisted back straight. Quote Link to comment Share on other sites More sharing options...
anvil Posted January 29, 2018 Share Posted January 29, 2018 To clarify. Instead of drawing out your large parent stock(2"square?) To 1" round and full length, forge the square stock transition to a short 6" long piece stub, then forge weld on a pie e of 1" round to final length. The 1" round on my candlabra was 36" or so. That's a lot of hammerwork! Thus the forge weld. Your situation here may be different. For aligning the twist. Take a short yellow heat on the round section. Clamp one of the square sections in a post vice with the top edge higher than the vice top. Place a short section of 1" angle iron on the square in the vice and another on the other square. Eyeball the two top edges, and twist til aligned. Support with stands as needed This should not creat any twist lines on the round section, so no correction needed. I believe using this angle iron is much quicker and more precise than clamping a long bar,,, that may or may not be twist free. When I do a picket, or long handrail, I start with the two pieces of angle touching each other. Then, move one angle iron out til I see the "sights" misalign. Mark with chalk, reclamp, straighten, then repeat. Quote Link to comment Share on other sites More sharing options...
anvil Posted January 29, 2018 Share Posted January 29, 2018 Joel OF, are these going to be hinge pins for a gate? Just curious Quote Link to comment Share on other sites More sharing options...
Joel OF Posted January 29, 2018 Author Share Posted January 29, 2018 Ah ok, I see where you're coming from on both accounts now. I never actually explained that my rounded up section only needs to be about 75mm (3") long. I like the angle iron trick though for checking straightness. You even take that one step further & clamp a scrap piece of bar to the vertical face of the angle iron & assuming you clamp the 2nd piece of angle iron in the same spot on the other side of the rounded up section, when the piece of scrap bar hits the verical face of the angle iron on the other side you know you're back to even. Dubious doodle attached. Quote Link to comment Share on other sites More sharing options...
anvil Posted January 29, 2018 Share Posted January 29, 2018 Rotate the two angle irons 90 degrees and use the top edges as a gun sight. No need for the bar. The angle iron edges are straight, your bar may not be. Nice drawing! Quote Link to comment Share on other sites More sharing options...
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