I thought it was about time to do some garage interior decorating. We all like comfortable spaces to live in that are littered with pleasant things that surround us. I had a few extra evenings of time in between some of my bigger projects so I figured I would tackle a task that has been sitting in the corner waiting to be completed.
A military friend of mine gave me a couple of worn out tank track sprockets from a Leopard C2 tank that is still in service. The C2 is the Canadian version of an upgraded German Leopard 1 tank. They were built between 1977 – 1979 weighing in at 42.5 tons. They sported a 38 liter Mercedes Benz diesel cranking out 830 HP which was able to push the tank to a top speed of 65 kph. Now 65 kph is the “official” speed however messing with the diesel pumps will push this monster to over 75 kph. If the tank couldn’t catch ya it would get ya with its 105mm rifled main gun. Well you can imagine what that kind of horsepower coupled with that kind of weight will do to a set of metal drive sprockets. These sprockets are equipped with wear marks that indicate when the sprocket is worn out and then requires replacement. I had the sprockets sitting around for awhile during which time I would brainstorm unique things to do with them. I suspect they each weigh around 80 pounds so they definitely have some heft to them. They would work as a fantastic base for a pedestal type of stand, thought about making a coffee table, a bar table with foot rest, plus lots a wacky stuff that would be completely useless when done. As the sprockets got stared at it was noted that there were 12 mounting holes around the perimeter. Hmmm…12 holes…..what else has 12. Case of beer? Yeah ok but so what? Build a beer can holder? Why? 12 inches in a foot, 12 stars featured in the flag of Europe, the Majestic 12, 12 ounces in a Troy pound. What else has 12 holes…this is a waste of time, it’s gotta be almost 12:00 and I have to get a move on. What to build, what to build. What’s the time? I have to get going…
So I couldn’t think of anything so I figured I would build a new shop clock for the garage. What would be cooler then having an eighty pound German tank sprocket hanging on the shop wall? Nothing! That’s why I did it. Obviously weight was going to be a factor. I went to the hardware store but I couldn’t find any picture hanging hooks that were rated for tank sprocket usage so I decided to build my own.
I TIG welded together a simple wall bracket out of mild still and splashed it with spray bomb. The bracket was built to span the 20 inch O.C. wall stud spacing. I was able to bolt the bracket into two studs using six 3” long 3/8” lag bolts. Trust me it is solid. The sprocket is going to hang from the bracket on a couple of ½” studs that were mounted into the brackets frame.
I used a battery operated clock motor therefore battery replacement had to be taken into consideration as a design aspect. The clock is not that easy to take down off the wall for the occasional battery replacement. I picked up a double A battery holder and soldered it into the clock motor which would allow me to remote mount the battery on top of the wall bracket. This way I had easy access to the electrons.
Now that the foundation was dealt with it was onto the actual clock. My instinct initially told me to grind down all the rough edges of the sprocket, clean off the rust, and give the unit a few coats of flat black. But the more I looked at the sprocket the more I started to see lots of character in its present state. I figured why do anything? Just leave it as is. So as far as sprocket prep went, there was none. It got left with rust and all.
The face plate was plasma cut out of .125 inch 6061 aluminum plate using my circle cutter. I thought it would look great with all the aluminum polished to a mirror finish so this is what I started to do. Once I got through the first 2 stages of polishing I set the aluminum plate into the sprocket for a quick visual. The soon to be clock started to take on more of a mirror look then a clock. The polishing did not blend well with the worn sprocket. I got out the dual action orbital sander, loaded it up with 220 grit paper and in about 2 minutes I had a fantastic orbital brushed finish to the plate. After a second visual, with the plate mounted in the sprocket, it was determined that this is the way to go.
Onto the numbers…I could have just left the mounting holes of the sprocket unfinished however I didn’t want it to look like I just hung scrap metal on the walls. I decided to spin up some aluminum inserts for the sprocket holes. I spun and few samples that had some nice bevels to them but in the end “fancy” was not meant to be. It really came down to creating something that was simple. In the end I spun out twelve 2” diameter buttons out of solid 6061 aluminum round bar. I had contemplated anodizing and dyeing the 3, 6, 9, and 12 buttons a funky color however I wasn’t sure if dyed aluminum would suit the project. I decided to leave all the buttons with a brushed finish.
So with the faceplate install, number buttons attached, and the clock hung it became evident that I made the right decisions along the way. The sprocket adds character to the shop and the choice of aluminum finishes blended well with the history. Now all I have to do is figure out what to build with the second sprocket I have.