Introduction: Viking Era, (800-1050) Padlock
While cruising Pinterest looking at Viking related posts I came across some drawings for very old locks/padlocks. I found a couple of designs that looked very straight forward that couple be built with materials and tools I have in my garage. So I figured I would have a go at putting one together.
My overall design criteria was as follows: KISS - keep it simple stupid, could be built in a couple of evenings, could be made with materials from the local hardware store & I had all the tools necessary. With the exception of a torch, everything else can be done with simple hand tools. I have some ideas that I will mention in this build that you could probably avoid using a torch all together.
Related site where the drawings/examples came from
Step 1: Design
So I based what I was going to build on this picture with some modifications on what I wanted to end up with.
Here are the materials I ended up using:
1. 2" x1/8" mild flat steel (ends of lock)
2. 2" x .065 wall tubing (center of lock)
3. 3/8" round bar stock (the shackle)
4. 7/16" nut (the shackle stop)
5. (4) 1/4-20 X 5" long bolts (to hold the lock together)
6. A piece of sheet steel 16 ga OR a piece of spring steel (for the springs)
Various files - small flat, rat tail, etc.
Various drills 1/8" 3/8" 1/4". etc.
Belt sander (or grinder - bench mounted or hand held)
Torch (to braze the spring steel springs to the shackle & heat and flatten the bolts)
Silver solder/brass rod to braze the springs to the shackle
Tin snips - to cut the spring material
Welder (I crash & burned on bending the shackle so I had to weld two pieces together)
Step 2: Layout
I did the layout of the end pieces using my cad program. Of course you can do the layout on the piece of steel with a square & punch. I printed out the bolt pattern on the printer 1:1 and glued it on the end pieces to save time
Step 3: The Shackle
For the shackle you are going to want one end of it longer by about 2-3 inches than the other. (The picture doesn't show this but I ended up cutting the shorter end even shorter)
Since I don't have a bender that will bend 3/8" round stock I got creative and tried to bend a radius like shown in the picture. It didn't work... But it did bend the first 90 deg of the rod OK. After looking at it I figured I could make two bends, cut them in half and weld them together! I used a piece of flat stock as a guide to make sure they stayed parallel when I welded them up.
Once it was done, I ground/filed a taper into the SHORTER end of the shackle. The initial angle/taper was just a guess-ta-mated to get me started. Turns out I had to make a couple of iterations before it was correct in the end.
When making the shackle please do make one end about 2"-3" longer than the other. This will be necessary when closing the lock. You want the top of the shackle to go through BOTH end pieces before the other end with the springs are inserted. It will act as a guide to line up the other end.
Having the shackle ends run parallel for their length is important! Since the shackle will be sliding through the two end pieces (a length of a couple of inches) if they aren't parallel they won't work - my mistake - your gain here :-)
Another note -
If you have access to other stock - or square stock that is bent in a 180 you could make your design around that.
Step 4: The End Pieces
You might ask why I'm doing the end pieces after the shackle.. It's because I needed to know what the distance between the two ends of the shackle were before I could drill the holes in the end plate.
So the end pieces. Four holes for the 1/4" bolts to hold it together. Two 3/8" holes - one for the shackle - the other I drilled so I could bolt the two pieces together when I was shaping them on the belt sander I used a combination of hacksaw & belt sander to come up with the shape for the end pieces. You probably don't need the 3/8" hole in the other end.
Step 5: The Body
When I laid out the design on the computer I figured it for a 1 1/2" dia tubing. Turns out I only had a 2" piece. So after some thought (and not wanting to buy any materials) I figured I would cut the side of the tubing and kind of roll it together. It worked out well and IMHO give the lock a more hand built look with the unclosed seam on the tubing.
How long is the body? Well I initially estimated the body at like 3 inches. I ended up trimming it down once everything started to come together.
Step 6: Square Hole for the Springs
So I need to square up the end plate so the shackle & springs will fit.
For the shackle end I first squared up the hole. I knew once the springs were added the whole would be taller on the vertical to accommodate the springs. This was a trial and error with multiple iterations to get to the finished hole. I didn't try to have it perfect the first time i squared it up. You can always file more later -but you can put it back...
Step 9: Add the Springs
Spring steel - were do I get it?
This is basically the steel strapping that is used to bind boxes/equipment to pallets. If you have a shipping & receiving at work, they will have a big roll of it that they use daily.
If you can't find any, a strip of sheet metal will work out. I initially used sheet metal but when I came across a piece of spring steel I went with that. The original spring I used is shown in the picture made out of sheet metal.
So you won't be able to bend the spring steel in half without breaking it (at least I couldn't) and if you heat it to bend it you will probably lose the 'spring' in it and/or it will get brittle or soft. So, with that, I used two separate pieces and silver soldered them to the shackle end.
If you don't have access to a torch, you could maybe use solder and a propane torch for fitting copper pipes together. That should work. You only need to solder the tip of the springs to the shackle - so like the first 1/4" of the tapered tip.
If you don't either of the above you can go real old school. So what you do is drill a hole through the springs & through the shackle slide a small nail through it, cut the nail short and flatten it with a hammer. Basically rivet the spring to the shackle.
So the taper length/depth of the shackle. I just trialed & error-ed it until I got something that looked correct. I wanted the square hole in the end piece to be as small as possible so I went with a long, fairly deep taper.
Step 10: Another Fitting & File the Key Slot
Once the springs can slide through the square hole and the top of the shackle fits easily through both end pieces things are looking good. You may have to shorten the springs or make a complete new spring that is longer. The square hole for the shackle may have to be widened either/both vertically or horizontally as well. Trial and error here. Remember a little at a time. You don't want to over do it and have to make another piece again.
For the key hole - what I did is mark where the line needed to be. Where is that? Well I know the width is going to be the width of the shackle hole (3/8") + I'm giving myself 3/16" extra on the sides for the key. That was my starting width. Height wise, I chose 1/8" because that will easily fit 16 ga sheet metal AND my flat file will fit through that. The distance of the key slot from the center was basically dictated by where it would fit between the center hole and the bottom two holes. What you have to watch is that the key will have a 90 deg bend it in so you want to make sure that everything will fit.
I drilled a series of 1/8" holes along the layout line. The holes couldn't overlap because the drill bit would run into them so I had to leave the minimum amount of space between them. Then, once the holes were drilled I used a chisel to cut the metal out in between. Old school but hey it is what it is.
Once I had a slot big enough to fit my file in, I went to work. I still have the blisters from using that little file with no handle on it to get that slot opened up. It was the correct file for the job though and only took about 15 minutes to work through it.
Step 11: Make the Key
I made a straight forward key for the lock. You'll find the blacksmiths that make these from scratch make some pretty cool keys and all but that's beyond my garage abilities.
I made the key out of 16 ga sheet metal. The same material I made the initial springs out of. IMHO any thinner metal and the key won't hold up very long and will twist & bend when you try to use it.
Cut a strip of metal about 3/8 inch wider than the square hole for the shackle
Mark the square hole on one end
DRILL a whole in the center of the square that is the width of the square hole to get you started (3/8")
FILE out the drill hole into a rectangle (more mini file blisters)
You want to make the rectangle for the key SMALLER on the vertical than the square hole in the end piece. Why? Because you DON'T want the key to be able to slide past and off of the lock springs when its being used. Why is this bad? Well because once the lock it bolted/welded/hammered shut and you put the key in and it slides past the springs you will have to disassemble the lock to remove it. :-) I had to make more than one key until I figured this out.
Step 12: Test Assembly, Adjustments and Adding the Stop Nut
So now you can test assemble the lock and see how it works.
It took me quite a bit of fiddling & tweaking & filing to get everything where it worked nicely.
Now is when I added the stop nut. That's the 7/16" square nut on the shackle just past the springs.
I used a very old square nut I had laying around for this. A washer or a piece of sheet metal cut and drilled will work as well. You can use a nut one bigger thread wise or drill a existing 3/8" nut out.
The nut has two purposes (in my mind anyways)
1. it prevents someone with mucking with the springs trying to pick the lock
2. it prevents the shackle from sliding too far forward and take a chance of the key sliding off the springs and getting stuck. Now if you cut your key correctly that won't be a problem but this can't hurt. And not having the shackle move in and out excessively is a nice touch.
I brazed up the nut so that the shackle springs just locked and had just a smidge of play - like 1/32" maybe. Not so tight that the lock won't lock up easily, not so loose that the free play is more than the width of my 16 ga key. You want to be careful here and not be too too precise. What happens in the next step when you rivet the lock shut the ends may be able to move some and your super good fit prior to this may be too tight or out of alignment. Mine was and I had to shorten the springs a bit so it would lock after I riveted it together.
At this point you should have a working lock, ready to button up permanently.
Step 13: Riveting the Lock Shut
So I could of cut and welded some 1/4" rods to the end plates and be done with it. Heck, I could of welded the tube body to the end plates but I was trying to make something that looked like the original and hand made as possible.
So what I did is get some 1/4-20 5" long bolts that have a long shank without threads that I could use for pseudo rivets.
I belt sanded the hex heads to look like rivet ends. Then I cut them so that they were about 1/8" longer than the length of the lock.
I also sanded the plating off of the bolts. I was planning on 'aging' the lock some and I didn't want the shiny new bolts to stand out.
Then with the lock assembled I clamped the bolt in the vice SUPER tight so that the cut end was sticking up out of the body but the body of the end plate was just sitting on the vice. Using the torch I heated the end of the bolt to just about where it was melting - orange hot and started nicely (nicely) hammering on the end to peen it over. It took doing this twice to get it peened over enough - as shown in the picture.
I initially tried to just heat up and peen over the end of the bolt with the other end of the bolt sitting on top of the vice. Despite having the end basically melted I manged to bend the bolt in the middle - hence the procedure described above.
Step 14: Aging/Antiquing the Lock
So I didn't want the lock to look new so I tried a couple of different things here to give it that 'antique' look.
1. Hot vinegar I saw something on YouTube about putting metal in hot vinegar to etch the metal. This only works on certain types of metal. Mild steel doesn't appear to be one of them.
2. Ferric chloride - There are some references to etching knife blades on this site that you can have a look at.
2. Bluing the metal. Lookup 'Birchwood Casey Super Blue Liquid Gun Blue' for more details. You can get this at any store that sells firearms. Big Five has it. Basically it etches the metal a nice dark blue. I did this on the key for the lock but decided not to do the lock You can kinda tell in the picture if you look at the key closely.
3. Paint, powder coat, leave it in the rain etc. etc. etc. Up to you.
By the time I was done putting this together it had some rust, tarnish & a worked look so I left it like it was.
Good luck, drop me an email if you have any questions.