Plug Welds the David Lisch Way
The ABS Master Smith shows how he puts a plug weld in a damascus blade
On this and the following pages, I will show you how to do a plug weld. Firstly, this is not a new technique. That being said, I would like to think that the way I am using it here is new—or at least it is new to my knives. I’m not showing how I made the damascus pattern as it would take way too many photos. Perhaps I will show that in another story.
The Moon Fighter is one of two knives I have made in this style. The first one was the Sun Fighter. The Sun Fighter was the first time I made a knife using the plug weld technique. I took an order for a knife like the Sun Fighter. Since the resulting knife was slightly different, therefore I named it the Moon Fighter.
HOW DAVE DOES IT
In Photo 1, I am cutting an oval hole into a forged integral blade. I forged the blade from a billet of my Star Night Damascus (Photo 2). It is important that the hole be an oval shape so it will be round once it is forged (Photo 3).
Blade thickness is just over 3/8 inch. This will give me room to forge the blade once I make the plug weld. Photo 4 shows the end of the moon billet. I will shape the square into the oval to the make the plug for the “moon.”
In Photo 5 you can see that the plug is ready for insertion into the hole. It is close to the right size but just a bit big. I put a slight taper on the edge of the plug so it can “find” the hole. The plug is an eighth inch thicker than the blade. This will allow the plug to expand and weld into the blade.
Above Photos 6 and 7: The hammer is a blur as the author pounds the plug into the hole in the hot steel.
With any process there is a learning curve. I learned that to get a really tight fit with the plug, it works best to put a dull red heat on the blade. Place the tapered plug into place and hammer it into the dull red blade (Photos 6 and 7). In Photo 8 the plug is in place. It is 1/16 inch proud on both sides of the blade. Back into the fire to a dull red and add flux.
In Photo 9 I have made the first weld. The moon is still visible. In Photo 10 the moon is still a bit cooler than the blade and is getting a bit bigger. Now is the time for some heat. Photo 11 shows work at the power hammer for some drawing down of thickness and adding length to the blade. It also makes the oval moon round and very hard to see.
In Photo 12 I am forging the blade close to its final shape. In Photo 13 I am drawing out the tip, adding more length to the blade. The moon is very close to being round. After a few final taps under the power hammer (Photo 14), I will finish tuning up the profile by hand.
NO SET FORMULA
I do not have a set formula for this process. It is by gut feeling. I can see how much the steel moves when I forge it. The first time I tried it I put a round hole into the blade and wound up with an oval, so it made sense to start with an oval hole if I wanted to wind up with a round one.
With the Sun Fighter the blade was 480-layer damascus and the “sun” was a very tight W’s-pattern damascus. Once I made the initial weld, the blade was still over 3/8-inch thick at that juncture. I ground in sunrays on both sides then forged up the rays and the sun to its round shape. On the Moon Fighter I wanted the backdrop to resemble shooting stars. This took some trial and error and a lot more time than I thought it would to get a pattern I liked.
There is no limit to the cool new things that can be done with damascus. I have heard folks say it has all been done before. Well, I don’t believe it. I think new and exciting things are happening in little knife shops all over the world, and the only way to keep things moving forward is to try new stuff and share the new things with everyone we can.
Please feel free to try this process. There are so many different things that can be done with it. When you come up with something new, share it so we continue to advance the art of damascus and knifemaking. Or, buy a damascus knife from your favorite maker and watch for that sparkle in his eye as he thinks to himself, “Cool, now I get to make another knife.”