PITTSFIELD – Dr. Rodney Chelberg, an emergency room physician at St. Joseph Hospital in Bangor, has a home in Pittsfield filled with the fruits of his artistic and self-taught abilities. There are handmade, hand-pegged wall bookcases, tiny turned bowls of birds-eye maple and ebony, and a nearly completed bench with chickadees created from tiny wooden inlays.

Stained-glass windows are installed around the home or hang individually in windows. The items are classic, graceful and exquisitely handcrafted.

But it is a big, yellow No. 2 pencil that is one of Chelberg’s most notable creations. The pencil is a quickly recognizable growth chart, a portable way to measure the leaps and bounds of children’s height.

This weekend, Chelberg, 48, and his wife, Mary, 40, are at the New England Trades Show in Boston, marketing the pencil to suppliers across the country.

From the emergency room to the manufacturing world is a big jump, Chelberg admitted recently. He has spent years navigating a maze of regulations, details and business connections.

“It all began when we moved here,” said the doctor. “We had marked the growth of our children on the door jamb in our home in Minnesota.” The couple realized with dismay that the marks, tracking their children’s history, had to be left behind. “We lost it,” said Chelberg, “the entire record.”

Not wanting that to happen again, Chelberg created the big yellow pencil, six feet of vinyl-covered wood that can be marked with a marker and moved from house to house. Coated with a high-gloss finish, the growth chart is quickly recognized by children.

“We have them placed in some stores along the coast,” he said. “Children come in and say, ‘How tall am I?’ and back up to the pencil. In some stores, there are dozens and dozens of names recorded.”

The Chelbergs said their product, which costs $40, fits in with their desire to promote healthy family relationships. “When we moved away from family, we often felt a lack of connection,” said Mary Chelberg. “Creating these kinds of memories builds family. Hopefully, this can turn into an heirloom. Then families won’t lose those memories.”

Once the first pencil was created, friends began requesting one for themselves. “We had people we didn’t even know driving up in the driveway, asking to buy a pencil,” said Rod Chelberg.

Chelberg now sells the pencil locally, through catalogs and through a division in China. “We now have four manufacturing firms bidding on making the product.” For now, the pencils are built in Winslow.

The doctor is currently working on four new styles: a rocket ship, a rose, a school ruler and a canoe. He is also working on several other inventions, which he is keeping secret right now.

“On the back of each pencil is a blessing from our family,” said Chelberg. “This is not just a product; it is a gift from one family to another, a way to reach out and touch people.”