Intro: Swiss Army Keys
I have been carrying a pocket knife along with my keys for quite a while and I never seem to use anything but the knife blade so I thought maybe i should get a smaller knife with only a blade. OR... maybe I could take out all that junk I never use and put my keys in there!!!
I didn't want to take apart my good Swiss army knife so I went digging for an old Chinese made Swiss army knockoff I have had since i was a kid. One of those big fat ones full of useless stuff.
I disassembled the knife thinking i was just going to use it as a template for my own custom made one but then quickly realized it would be far to difficult to reproduce a few items so I scavenged a few parts such as the springs and the spacers.
The photos in this instructable are from both my first somewhat successful attempt and from my second attempt which is MUCH better. I'll cover what i learned and why the second attempt worked out so much better.
Each layer can hold 3 keys so this could condense a pretty big pile of keys into a nice small package.
Step 1: Tools, Supplies
For this project I used the following tools.
Center Punch for marking holes
Drill with 1/8" drill bit.
Propane Torch, if you need to enlarge an existing items pivot hole
Screwdriver "T6" for pivot screws
Screwdriver flat blade for spring tweaking
Angle Cutters if you need to shorten some screws
Hand held Jig Saw
Dremel with metal cutting disk
Polishing compound "I used Mothers Billet polish"
Black Sharpie marker
Oh, and of course Safety Glasses
Materials I used
Guts from an old knock off swiss army knife
1/16" brass sheet
New Pivot Barrels
Small nail to knock out the old pins
Step 2: Disassemble the Swiss Army Knife
The first real step here is to pull out the toothpick and tweezers "if you haven't lost them already"
Find a really small screwdriver or long nail and slide it into the holes and gently pry them up.
You need to make sure you keep at least one of the plastic sides intact since you will be using that as a template for your new scales "the outside of the knife"
Once the sides are off, you will need to pound out the pins holding it together
Find a nail that is slightly smaller than the pin's and drive all the pins out of the knife. I had to use a center punch to make a little dimple in the top of the pins so my nail wouldn't slip off. after you finally get the first pin out, "straighten your nail or get another one" and punch out the other pins.
Once you get a few pins out you may notice the knife will start falling apart. Try and stuff most of the pieces back in until all the pins are removed so you don't bend anything important until all the pins are removed.
Step 3: Come Up With a Plan
Once you have all the parts, you need to collect all your keys and start planning the layout. How do you want to put in the keys? Make sure that one of the groves in each key can be used as a fingernail grip to open it.
Below is the initial plan I had made up. The parts on the paper is what I was going to re-use and the items to the side were for use as templates. I planned on putting my two normal sized keys in one slot and the large blade in a second slot. I then had two smaller keys which would be put on the bottom section. I also didn't feel comfortable with using that flimsy keychain attachment from the original knife so I planned on building my own.
The plan below is from my first attempt and here is what I learned from that.
1. Do not attempt to re-use the pins. They will squish inside the knife as you hammer them and freeze everything so it won't open! After some research i found out that the Mfr uses a spinning drill press like thing to super-heat and press just the ends of the pins.
2. Do not use the inside metal sides as the template for your scales. They are too small. Use the Plastic sides as your template for your new scales.
3. Don't use the knife blade as the template to re-shape the head of your keys, It's too long and won't profile the short head of your keys properly. Use the shortest thing you have like the can opener as you should notice a much more pronounced bump that is required to hold the keys up far enough to grab once closed.
After much online searching for an alternative to the existing pins, i found a website that sells parts to knife makers. I purchased the following. 3 - 1/8" x 5/16" pivot barrels with screws and 1 - 1/8" x 7/16" pivot barrel with screws for a whopping $11 which included shipping.
I also ordered some 1/8" thick brass rod to use as they keychain loop but it kept breaking so don't bother with that.
Step 4: Cut Out the Scales
Trace the plastic scales from the old knife onto the material you plan on using for the scales.
I have a piece of 1/16" brass "or copper?" sheet that has been in the garage so i used that.
Make sure you leave the line when you cut so there is tweak room later. I used my hand held Jig saw to cut out the scales.
After both pieces are cut out, clamp them together in a vise and File down to the line while they are clamped together. This will make sure that everything lines up properly.
Now, you need to dig out one of the inner scales from the pile of old knife parts and center it on one of your new scales. Using a center punch, mark where each of the pin holes will be made.
Again clamp the two sides together and drill the pin holes through both sides at the same time so everything lines up perfectly "unlike my first attempt"
Step 5: Reshape Your Key Heads
Collect all of your keys and the parts you will use to trace the new heads.
I used a black sharpie to color on the head and the tip to a drywall screw to scratch around my template. I made marks all along the outside of the template to make it easier to see.
If your key head is not big enough to include the lower most part of the bump in the bottom of the template then leave plenty of extra material on the bottom as you will need to fiddle with it to ensure the key sticks up enough to grab to pull out. I ended up having to use my Dremel to cut the heads as they were way to small for my jig saw.
Once they key head has been re-shaped, mark with a center punch where the new hole will be for the pivot and drill an 1/8" hole to match the new pivots that were purchased.
I used a scrap piece of wood to drill on and because everything was so small I couldn't hold the keys while drilling them so I just put a screw into the board and placed the key against that to prevent it from spinning while I drilled the pivot holes.
The Blade that I planned on re-using had the pivot hole a little to small to fit over the new Pivots so I had to re-drill it with an 1/8" drill bit. Turns out, that is one HARD piece of steel. I broke one drill bit before I figured out I had to anneal "soften" it. Not wanting to ruin the whole blade I held it with my pliers and put just the pivot part over a Propane torch until it turned cherry red and let it air cool. Not enough, broke another drill bit. Again, I held it in the propane torch until cherry read and left it in the flame for a good minute after. Let it air cool and this time I was finally able to enlarge the hole but it still ruined a 3rd drill bit. SO, make sure this is the last thing you drill.
Step 6: Fit All the Pieces Together
I don't have a picture of the inside while I was fitting everything together because, well, I was to busy swearing and getting really frustrated getting everything to seat properly. Everything is under tension with those springs so it's a lot of fiddling and pushing with a screwdriver here, squeezing with some pliers there to get everything lined up so you can get the new pivots all the way through.
The pivots that I purchases came with two screws for each pivot but the screws were too long to put both all the way in. So, after some scrounging i found a nut small enough to fit the screws, Cut about half the screws off, then took off the nut to re-set the threads.
At this point I also cut out a strip of brass 1/4" wide by 2 1/2" long for the keychain loop.
I bent it into 1" long sides and matched the thickness of the knife. I then carved a scrap piece of wood to fit in between the arms and drilled an 1/8" hole through both sides to fit onto the longer 7/16" pivot.
Step 7: Final Fitting, Sanding, Polishing
Once you are sure everything fits properly and is how you want it, then you need to disassemble everything and give it a good sanding to round over all the edges and polish it up. Give it a good coat of paste wax and then re-assemble everything using the new pivots and the screws. I'm going to need to use some lock-tite on the screws as I can't tighten a few of them all the way else it makes it too tight.