Goods Posted October 18, 2022 Share Posted October 18, 2022 I’m not sure about quality of the weld itself, but the issue you are seeing is most likely from not tapering the edge of your material enough. With a thick edge on a scarf, that edge gets hammered into the material it’s being welded to, creating what looks like a crack along the weld. It is a weak spot. Mark Aspery has a good video on YouTube (“Forge-Welding: Scarf-Theory “) that explains this very well. On the weld quality side, when you are grinding into it heavily, like in the pictures above, if the weld is bad, often you will see the bad areas over heating and bluing. A bad weld won’t conduct the heat away like a good weld/single piece of steel. Any reason you went with a lap weld as opposed to a traditional split bit weld. I would think a split weld would be much safer unless there is a specific need… (I find them easier also.) Keep it fun, David Quote Link to comment Share on other sites More sharing options...
Hefty Posted October 18, 2022 Author Share Posted October 18, 2022 Hmmmm, I may have some sections that haven't taken properly then. The are a few little blued spots at the edge. I went with the lap weld because I had drawn out the parent material too thin in trying to get some depth in the blade section. My original intent was to split the end and insert the bit but I had seen this method in a video somewhere (I think it was one of John switzer's videos) and thought it would be a less fiddly solution to my problem. Quote Link to comment Share on other sites More sharing options...
Goods Posted October 18, 2022 Share Posted October 18, 2022 You see lap welds like this a lot in particular applications. Carving axes, wood chisels, bowl adzes and other tools that need to have the hard sharp edge all to one side is we’re I’ve seen it the most. Not a really big deal, just something to consider. On a split bit weld, if it’s not perfect you have the material supported on either side and the biggest issue you may have is the bit getting stuck in your target or pieces of the target getting stuck in the scarf as it peels back. Also, one trick is to use the bit to add more material to get the size you need. If it looks like your going to run short on length or width, stop and split and scarf the end. Then you can work out how thick or long you bit needs to be to finish it out. (I’m not trying to be critical, just trying to help out and give options.) Keep it fun, David Quote Link to comment Share on other sites More sharing options...
Hefty Posted October 18, 2022 Author Share Posted October 18, 2022 Any guidelines or rules-of-thumb for proportional depth of split or thickness either side of the split for this style of weld? I have another one of these spike hawks started but I haven't drawn out the depth. I have some leaf spring that is a little deeper and thicker that I can make the bit from. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted October 19, 2022 Share Posted October 19, 2022 I have a steeled WI adz where the steel part is 100% lap weld. (And the steel is very thin compared to the WI body.) I wonder about the use of the term "traditional" for a split bit weld. "Knives and Scabbards, Medieval finds from excavations in London" lists 7 different methods of combining Iron and Steel in tools: all iron, all steel, spine weld, lap weld, split bit, >> chevron bit, piled. IIRC the Chevron bit was used in a film about axe making in a "traditional factory" in the USA that was posted on IFI years ago. Quote Link to comment Share on other sites More sharing options...
Goods Posted October 19, 2022 Share Posted October 19, 2022 I guess using “traditional” for this was not the best or even correct term. I probably should have used more common today? “Traditional” for who? When? Where? Not very clear… I’ve only made two punched and drifted hatchets. One fully hardenable. The other steeled wrought iron. For the steeled one the bit was pretty short maybe 1/2” scarf with 1/4” exposed bit. For my wrapped hawks, the bit is about 2” deep with the bit exposed 1/4” to 1”. I mainly use the bit thickness to gain width, but you can move the material where you need it. Just down let it get away from you. David Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted October 19, 2022 Share Posted October 19, 2022 Thanks for clarification; "Traditional" is one of my hot buttons as smithing has been around about 3000 years over most of the world; so "traditional" is very much a when? & where? type of thing. Quote Link to comment Share on other sites More sharing options...
Goods Posted October 19, 2022 Share Posted October 19, 2022 Yeah, I understand where you’re coming from. I had to go back and re-read my post, I didn’t even realize that I had used “traditional”. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.