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Retirement project that keeps brain ticking

St. Cloud man constructs large wooden digital clock

By Bill Vossler

John Forner, of St. Cloud, has spent thousands of hours during the past eight years of his retirement working on a single, but very complicated project -- constructing a five-foot-diameter digital clock out of oak, birch, and plywood. It’s so large he could not get it out of his basement without dismantling it--and it was not designed or constructed to be dismantled – a minor detail for him.

John Forner of St. Cloud works on his first prototype of a digital clock made of oak, birch, and plywood. Contributed photo

“About 30 years ago, I was touring the workshop of master clockmaker Jim Borden, and I was amazed at all the gears, pendulums, escapement mechanisms, parts and pieces of the wooden creations he was making,” said John. “In the spur of the moment I blurted out, ‘You know Jim, there’s got to be a way to build a wooden digital clock.’”

Jim had no clue then where John’s computer programmer thoughts were headed, but that simple statement spurred John to (eventually) attempt to find a way to build a mechanical digital clock.

John knew it would be a difficult project What he didn’t know was how difficult and how complicated.

“I scoured the Internet for anyone else who may have proposed this same thought--and acted upon it.”

But without luck finding that, he knew he would have to build it himself.

Clocking the History

The history for his clock harkens back to John’s high school days in Cold Spring. In 1968, at an all-school lyceum, he and other students were volunteered to come down to the gym floor to hold up cards to demonstrate how numbers are added in our common base 10 system, and then to show how the base two system was used inside computers.

That freshman day, John also made first contact with a “desktop” computer. “It was the size of a small refrigerator, with lots of blinking lights, and you used toggle switches to program it. It’s circuit boards were the size of a newspaper page.”

It amazes John that today’s 2-year-olds have more computing power at their fingertips than what he saw at that lyceum that day.

“I was very curious and knew I wanted to learn everything I could about electronics and computers. Little did I know then how much I’d need to master binary, Boolean logic, and base two counting. It was such an important aspect of my working life…and for building wooden digital clocks.”

From that time forward, much of what John did in his life led in small ways or big, into constructing that wooden digital clock. So, his ham radio time, learning Morse code and computer science, building an electric digital clock in college, knowing how to run a computer router, photo processing, making stained glass windows, working in the drafting department at Cold Spring Granite (Coldspring Granite now), and his lifelong woodworking hobby. All of these skill added degrees of proficiency and information in knowing how to build his clock.

Early Planning

From the first, John said, he had a fundamental and purist vision of what the clock should contain and how it should work.

“I was thinking this clock had to count numbers like a computer and display time not like the hands of our analog clocks, but as 7-segment digits. And it had to be completely mechanical--no electronics allowed--and like Jim’s clocks, it must be art.”

And these were the parameters he worked around.

John shows different parts of the clock. The pieces of wood are extruded to form numbers and show the time. Contributed photo

John said before he retired, he started working on the project, but hit a few dead ends. “Then one day while searching on the Internet I stumbled onto a YouTube video of the mechanical counter system I’m using in the clock - it counts time in binary bits. That video showed a marble flip-flopping mechanical levers on and off. My eureka moment came on a morning walk some eight years ago when I realized all I needed to do is lose the marble, replace it with a rod attached to the seconds hand of the clock, guided around a circular track. So obviously simple! So, I knew all I had to do to get my first clock running was to replace the marble, and count time.”

The most fun doing the project, John said, has been trying to figure out the complex logic piece by piece on those long walks on the St. Cloud Beaver Island trail. “For each prototype, I’ve done a thousand hours of drafting and cutting time. It’s slow work, and almost a job, but it’s my passion, and it’s an enjoyable one for me.”

Then came retirement, and John’s focus working on prototypes 1 and 2 and 3.

“In the last eight years since I retired, my wife Mary and I bought a teardrop camper, and squeezed in 60,000 miles camping in all of Minnesota’s state parks and almost all of our of national parks.”

That gave him a respite from the detailed and complicated work of designing and creating the clock.

“It took me most of a year to draw up the CAD (computer-aided drawing) plans for the first clock – in between all our travels. I eventually purchased my own CNC router and started cutting pieces. I have enjoyed all of it. Retirement is the best!”

In the midst of all this, John continued to take those long walks on the Beaver Island trail, where he contemplated problems of how to make the parts and logic of the clock work.

Not Everything Is Perfect

Some parts of the work can be discouraging, he said. “I would run into issues with the first prototype, I was 10,000th of an inch off, and the clock wouldn’t work until I remade the whole front panel because of that tolerance issue.”

Obstacles like that could be come a final dead end for some, but not John.

“You have to have a passion for it, and that has been my joy for the last eight years inventing something no one else has tried before. I enjoy working on the parts and drawing all of them out using my computer CAD experience I got while working at Cold Spring Granite Co. in the drafting department, for so many years.”

“The best descriptive word I can think of to tell you how this display works is: Extrude. The individual segments of each digit just come forth, are pushed out, pop out at you, and are extruded from the face of this clock. Each display segment is fixed to a rod in the display assembly. While the face of the clock has a mesmerizing beauty, the back side is all business. There are levers pushing cables, pulling rods to display the correct time.”

A close-up of the clock shows how complicated making this clock was for John. Photo by Bill Vossler

John has two words to describe how the decoder section of his clock converts the binary counts of the minutes, tens of minutes and hours to turn on the right segment of each seven-segment display digit. Those two words are, ‘patent -pending.”

Sometimes parts of his work can be pretty expensive. Recently, to help with dismantling it properly to move, he had the clock’s three largest pieces done at a CNC shop in the Twin Cities, which cost him over $1,000. “So, I’ve got several thousand dollars in each prototype.” Luckily, his wife is aboard, too, as she has her own expensive compliment of hobbies to keep her enriched, while John is in his basement workshop making sawdust!

“It’s been a zigzag stepping-stone, learning curve process,” he said. “I have lived during an amazing time that has given all of us amazing tools to do amazing and awe-inspiring things. We humans have so much more yet to invent and discover. Certainly, someone will improve upon my ideas and build a better wooden digital clock someday.”

Or perhaps a wooden digital computer, for which John already has plans spinning around in his brain. “And my clock counters and decoder circuits will come in handy for its display.”

John said he’s never felt like quitting, despite working on this project for eight years.

John has shown his clock to numerous people. “Everybody who sees it, the first word out of their mouths is ‘Wow!’”

Those accolades keep him going. He still isn’t finished. “I’ve got ideas for prototype number four, for improving and coming up with a better design. For example, my current one has some issues with its main bearing. It’s not reliable enough yet to run 24 hours a day, 365 days a year. But I’ll figure it out."

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