Every so often, a routine tool hunt turns into something special. That’s exactly what happened when I spotted an ad on Facebook Marketplace for a small bundle of moulding planes just fifteen minutes from home. The price looked fair, and I noticed the seller had a few other planes listed as well—always a good sign.
When I arrived, one of those other planes immediately caught my eye: a Mathieson No. 9B Plough Plane. To my surprise, it was in excellent condition, with only minor damage to the wooden thread on one of the stems. Even better, the asking price was low enough that it felt like a very easy decision—so I bought it on the spot.
Back home, a bit of research confirmed what my instincts suspected. The plane had been priced at roughly 10% of its true value. Needless to say, this was one of those rare Marketplace finds that makes the hunt worthwhile.
What Is the No. 9B Plough Plane?
Among Mathieson’s many tools, the No. 9B screw-stem plough plane stands out as a fine example of their ingenuity and craftsmanship.
The 9B was designed for cutting grooves (ploughing) with great accuracy, allowing woodworkers to adjust both depth and width. Its construction typically featured a beechwood body paired with boxwood screw stems and nuts, a combination that balanced strength with a refined finish.
These planes were often supplied with a set of interchangeable blades—commonly around eight cutters, ranging from 3 mm to 14 mm. While many cutters were made by Mathieson, it was not unusual to find blades from other leading makers of the time, such as Rob Sorby or John Moseley & Son. My purchase just had a single 5mm blade.
Historical Context & Design Highlights
The No. 9B plough plane represents the best of mid- to late-19th-century British woodworking tool design. At a time when hand tools were still essential in every joiner’s workshop, this plane combined traditional wooden construction with adjustable features that gave craftsmen far more control than earlier models.
One of its key innovations was the screw-stem fence, which allowed for precise positioning of the groove—a significant improvement over simpler fixed-fence designs. This made the 9B especially useful for tasks like fitting panels, making doors, and cutting grooves for mouldings.
To a 19th-century carpenter or joiner, a plough plane wasn’t a luxury—it was an everyday essential. Today, the Mathieson No. 9B is prized not only for its function but also as a piece of woodworking history, a tangible reminder of a time when tools were built to last generations.
The 9B Also Opened the Door to a Major Buy
Buying the Mathieson No. 9B plough plane turned out to be more than just adding another fine tool to the collection—it also led me to one of my biggest finds yet.
The seller was a retired Industrial Arts teacher, and best described as a bit of a picker—someone with a keen eye for bargains that could be resold. We ended up talking for quite a while. During our chat, he pulled out a couple of planes he wasn’t planning on parting with, but wasn’t sure about their value.
To my surprise, one was a Stanley No. 1, and the other a Norris infill plane—both highly collectible and sought after. I was able to share some information about each, which he genuinely appreciated.
Then he brought out something even more intriguing: a builder’s chest full of wooden planes—forty-four in total—picked up at a deceased estate sale. At the time, he wasn’t offering it for sale, but the sight of it stuck in my mind.
A few days later, I got back in touch with him and negotiated the purchase of that builder’s chest. It’s a fascinating haul, and I’ll be sharing the full story in an upcoming post—so stay tuned!
Blog compiled with the help of ChatGPT