->A much higher complexity level
->Requires more time
->Requires more esoteric building materials
->Much harder to circumvent/guess
->User changeable code
This instructable will take you through constructing a wooden dial combination lock. This particular lock will in fact be used to secure a minibar fridge (replacing the one I have already built) due to some issues with the misappropriation of foodstuffs at my workplace.
This is a moderately complex project that can be completed inside of 9 hours if you move quickly and don't make any major mistakes. Workpeice precision is a must in this project, and you should assure that you have access to some moderately precise tooling.
During the course of this project you will also be creating the dial in virtual format using openoffice (marking it by hand would be a disaster) and then printing it to transfer it permanently to the dials on the finished product.
Openoffice with fontwork installed
3/4 inch pine
1/2" internal diameter compression type spring
Nail gun nails
Step 1: Initial prep
Cut the following pieces:
3 9x12" boards
2 3x12" boards
1 3x32" board
9 3,1/2" disks
4 2,1/2" dowel
2 5" dowel
Step 2: Prepare the slide mechanisim
Step 3: Prepare and drill the lock plate
Use a 1/2" drill bit on the lock plate to make larger holes.
Screw in some 1" screws into the slide.
When complete it should look like the last picture here; with screws poking up into the holes, holding the slide firmly in place with minimal play.
Step 4: Preapre the dial plate
Drill these out on the drill press to 1/2", then wiggel them around in the drill press to make them SLIGHTLY larger then 1/2"- your 1/2" dowel should be able to freely rotate in these holes, but otherwise be held firmly in place.
Step 5: Cut 9 disks
Step 6: Find the centre of one disk
Once you have found the centre point, transfer it to all other disks.
Then drill out each disk with the 1/2" drill bit on the drill press.
You should drill the hole with a small drill bit first so that the disk does not want to shift as you press the 1/2" into it, this will help keep the holes consistent and in the middle- absolutely precision is NOT required here, but your final product will look far more sloppy if it is not at least close.
Step 7: Add an offset hole to 4 disks
Step 8: Glue the dowel into the 4 disks with offset holes
Step 9: Drill marker holes in the dial plate where the offset holes in the disks are
Step 10: Place your marked disk plate onto the lock plate, and tansfer the holes, and make slide rods
Step 11: Create the dial pattern
click on 'fontworks gallery' in the window that appears
Select the default display
Type in your number series (Tip- remember to include zero and an ' above each number; unlike me....)
Select Circle format
Use the yellow circle to make all numbers be around the outside edge.
Make fill colour black
Change shape and size so that it will fill your disks.
make 4 of them
Cut out each one
Attach with spray adhesive
Step 13: Put it together
(Spring not installed in side view images so I could illustrate what I am talking about above)
Step 14: Attach a pull handle to the lock plate
First thing, lets make it easier to move; attach two bars similar to what is holding the dial plate to the base plate to the lock plate (And only the lock plate) then connect these via another piece of the dowel, so that there is a sturdy handhold which will pull evenly directly against the spring.
Step 15: Add position indicators
Step 16: Drill angled holes into the dowel
Step 17: Mount and set combination
Since the screws in the lock plate are preventing the offset hole disks from rotating, and the pins preventing the numbered dials from rotating have been removed the numbered dials will rotate to whatever number you want to be the new code. Replace the pins when complete to assure that they do not rotate accidentally.
Also- if you are me you realize that adding a zero, and a zero tick at this point might be a good idea, so you add that with the sharpie again.
If you've made it this far you now have a rather complex, somewhat bulky, and functional lock that has roughly the resilience of a suitcase lock. It does however look quite impressive and can hopefully inspire people to not steal things from your fridge/other locked location. Changing the code will also build your upper body strength if you used a spring with as much resistance as I did.