Restoration of a German Folding Dirk circa 1910-1930
Posted: Tue Aug 20, 2019 4:44 am
This project is the restoration of a folding dirk made by J Dirlam & Sons, Solingen Germany. John Goins guesstimates the date of this company to be 1910-1930.
I had posted previously a few pictures of this knife in a topic called "Your Opinion Wanted!"
viewtopic.php?f=14&t=61121&hilit=Derlam&start=15
The topic was about dying bone handle slabs. I used the same basic method but using a light brown Febings leather dye called British Tan. I was definitely surprised by the results!
I will list a few pictures and describe the steps as I go along.
This is the before picture:
These three pictures show the knife in pieces: These are liners I cut from .040” brass sheet. As you can see I used layout fluid to scratch the outline of the holes from the liner on to the new liners. It was a straight up tracing from the liner on to the new brass sheet. I cut the liners out with aviation snips and then clean the edges up on a 5 inch disk sander.
The second picture shows the two new liners clamped to the old liner I used as a pattern for the holes. Re-creating a working mechanism – the knife is been apart for months and I wanted to set the mechanism up so I could watch it work before I assembled the knife. Cleaning bolsters – The knife is between 89 and 109 years old, there was lots of crud in the hollow bolsters and so me I suspect was solder that has broken down over the years. I learned to solder it was not electronic soldering. I was taught to get some flux hot and melted on each surface and get a little bit of the solder melted onto that flux. A little bit of that solder will adhere to the metal that is a process known is tinning. I want this tinned coat of solder very thin, so will be liner or bolster is still hot and the solder is still liquid I rap the liner on the edge of a small anvil on my workbench to knock off the excess solder. With the bolster I used an air hose to blow off the excess solder. This is not a clean soldered joint in this case because of the dirt in the old solder and bolster, nevertheless it is a thin coating of solder and it is attached to both pieces which is the major objective.
Soldering tinned bolster to tinned liner - This is fairly easy if the solder is a very thin coat. Just like the bolster and the precise position you want it on the liner and heat the two items with a little torch. If the solder on the two items is a thin coating then they will both melt and harden in place when the heat is removed. If you have a thicker layer of solder, solder becomes liquid it tends to flow in the bolster is floating on the solder and it shifts position and you have a bolster that is not in the right place. DO NOT, I repeat, DO NOT grab the bolster and move it into position with your fingers. If you still have feeling left in your fingers, you will immediately know that you still have feeling there!
A thin coating on both parts, put them in the correct position, heat them up till the solder melts on both pieces, then remove the heat and they will harden into the proper position if you do not have too much solder on the parts.
I will have to get more pics & text ready for the next post.
I hope y'all enjoy the pictures and the description of the process.
I had posted previously a few pictures of this knife in a topic called "Your Opinion Wanted!"
viewtopic.php?f=14&t=61121&hilit=Derlam&start=15
The topic was about dying bone handle slabs. I used the same basic method but using a light brown Febings leather dye called British Tan. I was definitely surprised by the results!
I will list a few pictures and describe the steps as I go along.
This is the before picture:
These three pictures show the knife in pieces: These are liners I cut from .040” brass sheet. As you can see I used layout fluid to scratch the outline of the holes from the liner on to the new liners. It was a straight up tracing from the liner on to the new brass sheet. I cut the liners out with aviation snips and then clean the edges up on a 5 inch disk sander.
The second picture shows the two new liners clamped to the old liner I used as a pattern for the holes. Re-creating a working mechanism – the knife is been apart for months and I wanted to set the mechanism up so I could watch it work before I assembled the knife. Cleaning bolsters – The knife is between 89 and 109 years old, there was lots of crud in the hollow bolsters and so me I suspect was solder that has broken down over the years. I learned to solder it was not electronic soldering. I was taught to get some flux hot and melted on each surface and get a little bit of the solder melted onto that flux. A little bit of that solder will adhere to the metal that is a process known is tinning. I want this tinned coat of solder very thin, so will be liner or bolster is still hot and the solder is still liquid I rap the liner on the edge of a small anvil on my workbench to knock off the excess solder. With the bolster I used an air hose to blow off the excess solder. This is not a clean soldered joint in this case because of the dirt in the old solder and bolster, nevertheless it is a thin coating of solder and it is attached to both pieces which is the major objective.
Soldering tinned bolster to tinned liner - This is fairly easy if the solder is a very thin coat. Just like the bolster and the precise position you want it on the liner and heat the two items with a little torch. If the solder on the two items is a thin coating then they will both melt and harden in place when the heat is removed. If you have a thicker layer of solder, solder becomes liquid it tends to flow in the bolster is floating on the solder and it shifts position and you have a bolster that is not in the right place. DO NOT, I repeat, DO NOT grab the bolster and move it into position with your fingers. If you still have feeling left in your fingers, you will immediately know that you still have feeling there!
A thin coating on both parts, put them in the correct position, heat them up till the solder melts on both pieces, then remove the heat and they will harden into the proper position if you do not have too much solder on the parts.
I will have to get more pics & text ready for the next post.
I hope y'all enjoy the pictures and the description of the process.