Perpetual Desk Calendar in Cherry

My son came to me with a photo that he found online of a desk calendar made out of wooden blocks. It was originally from pinterest or some similar website. I took that idea, tweaked the design and built this for him out of solid cherry.

It is really a quick and easy DIY project. You could probably knock one out in an afternoon if you tried. It doesn’t take much wood. There are all kinds of way you could build one. (I found one online that seemed to be mostly made of cardboard.)

If you would prefer, you can watch a video of this project build. Otherwise, read on!

There are three parts to this. First there are the two large day blocks. I made these to be 2" cubes. These must be cubes for this to work.

Next, there are the three month blocks. These are the three long and slender blocks that sit under the day blocks. These display the current month. These blocks are approximately 2/3" of an inch in cross section and 2" long. I know, 2/3" is not a common woodworking measurement! There are three blocks, which fit under the day blocks, so their dimension need to work out to be one third of two inches, in order for it to fit neatly. A settings of 11/16" is pretty close to what you need.

Finally, there is a simple display stand for holding and displaying the calendar blocks. I made the base to be about 4" by 6", and the walls are approximately 3/8" thick, and just a bit higher than the blocks.

So, How Does It Work?

We count by tens (0-9), but there are only six faces on a cube. So how do you get these cubes to count up to ten? One key fact is that you only need to count up to 31 -- the longest month.

On the one block, you need the numbers: 0,1,2,3,4,5.

On the second block you need the numbers: 0,1,2,6,7,8.

It seems confusing, but it works. You start the month using the first block, up until the 5th of the month. (and the other block is set to 0, so dates are shown as 01, 02, and so on.) Then you switch the blocks around and continue using the 6,7,8 on the 2nd block. For the 9th, you take the 6 and turn it upside-down, so we have 06, 07, 08, and then 09.

The reason for having 0,1,2 on both blocks is that for the 0-5 on the first block you need a matching 1 and 2 on the other block, so that you can write 10,11,12,13,14,15 and also 20-25 as well as 30-31. Then, when you swap to the other block for writing 16-19 and later on 26-29 you need a matching 1 and 2 on the first block. (If you think it through, this method would fall apart if we had to count higher than 32, as you can NOT display 33 with this setup.)

It's a bit confusing, but it all works out, and the key is the ability to use the same character as the 6 and the 9. Unfortunately, you MUST use a 0 in front of the single digits. You can't just have a 7 for instance, you need to write it as "07", and the same for all the numbers 01-09. We just don't have another block face available to have a blank. All the faces are used.

The month blocks are easy: There are three month blocks, each one has four long faces available. That gives us a total of twelve spaces, one for each month.

This is a small project and does not take much wood. I was able to build this entire project out of one piece of cherry hardwood, about 29" long and a bit over 4-1/2" wide, and about 3/4-7/8" thick.

I did not have 2" thick stock, so I had to glue up three pieces to give me a blank that was large enough to provide two 2" cubes. I glued up 3 pieces which were each about 5" long, by 2-1/2" wide.

After the large blank was dry, I set about cutting it into two-inch cubes. This piece was too small to comfortably cut using my tablesaw fence. So I set up a stop block on my crosscut sled at the two inch mark, and then cut out the cubes that way. After each cut I would rotate the piece and reclamp it to cut another side. (I think that this bit is much clearer in the video!)

While the big day block blank was clamped and drying I moved on and ripped down the month blocks to be approximately 11/16" by 11/16" in cross section (1st photo). Three of these need to line up and and be places under the two date blocks, so their thickness and width needs to add up to about 2" when three are placed side by side. I did not cut these to final length until the display stand was built, so that the length could be measured from that -- though it will be close to 2" in length.

From the remaining chunk of cherry I cut out a 4" x 6" piece for the base, which I left at full thickness.

The rest of it I resawed in half to make the "walls" that would wrap around the calendar blocks.

I cut the "wall" parts to length and cut down the two front corners of the sides. I then glued those together and pinned the joints with 23 guage brads. I know that a butt joint is not particularly strong, but this is a light-duty project and it will be glued down onto the base, which should make it plenty strong. (In the 4th photo I am showing how it will be attached to the base.

I set up my router table with a cove bit and cut a decorative cove edging along the front and two sides of the base.

My son asked me to carve in the numbers onto the blocks and not just paint them on. So I used my X-Carve machine to carve in the day numbers. You could just paint them, or hand-carve them, or use the toner-transfer method, or glue on some stickers... I'm sure that you get the idea. You do not need a fancy CNC machine for this step!

I then painted black paint into the number carvings which really makes them stand out beautifully.

The excess paint was easily sanded off of the blocks, leaving a clear contrast between the bright cherry and the dark black carved numbers.

I wanted to carve the month names into the month blocks, but I did not have a bit that was small enough to carve the letters. So for those blocks I used the Toner Transfer Method (Link to John Heisz' ibuildit.ca website for a tutorial). With this method you print in reverse using a laser printer and then use acetone to transfer the toner from the paper to the wood. The result is not 100% perfect, but I like the look.

I sprayed on a few coats of lacquer for a finish.

And here are some photos of the finished project

Thanks for reading!