This is a trimming technique I like to introduce to beginning students as they learn to throw and trim. It uses a modified thumbtack to establish a predetermined wall thickness. As clay is trimmed away, the trimming tool will lightly “tick” against the thumbtack head once the desired thickness is reached, providing both an audible and tactile cue.
Using a bowl as an example, take a thumbtack and clip the pointy end shorter with pliers or scissors so the remaining shaft matches your desired wall thickness (1). Insert the thumbtack into the interior wall of the bowl at the area to be trimmed (2). Multiple tacks can be used if you want to check thickness in more than one location.
Continue to trim as usual. When the trimming tool contacts the head of the tack, you’ll feel and hear a subtle tick—signaling that the target thickness has been reached (3). You will also see the head of the tack. Once this happens, remove the tack and compress clay into the hole from both sides of the wall to seal it.
The real magic of this trick? It builds confidence in beginners by giving instant feedback and eliminating blind guessing. Pair it with gently tapping the wall to listen to the sound, and students quickly tune their ears and eyes to its thickness. Flipping the pot for a visual check reinforces the feel in their hands and memory. Before long, they’ll throw evenly more consistently from the start, trim less overall, and phase out the tacks entirely as proficiency takes over.
I can’t remember who first taught me this trick. It could have been any one of the many inspirational potters I’ve encountered along my journey in clay. Whoever it was—thank you.
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This is a trimming technique I like to introduce to beginning students as they learn to throw and trim. It uses a modified thumbtack to establish a predetermined wall thickness. As clay is trimmed away, the trimming tool will lightly “tick” against the thumbtack head once the desired thickness is reached, providing both an audible and tactile cue.
Using a bowl as an example, take a thumbtack and clip the pointy end shorter with pliers or scissors so the remaining shaft matches your desired wall thickness (1). Insert the thumbtack into the interior wall of the bowl at the area to be trimmed (2). Multiple tacks can be used if you want to check thickness in more than one location.
Continue to trim as usual. When the trimming tool contacts the head of the tack, you’ll feel and hear a subtle tick—signaling that the target thickness has been reached (3). You will also see the head of the tack. Once this happens, remove the tack and compress clay into the hole from both sides of the wall to seal it.
The real magic of this trick? It builds confidence in beginners by giving instant feedback and eliminating blind guessing. Pair it with gently tapping the wall to listen to the sound, and students quickly tune their ears and eyes to its thickness. Flipping the pot for a visual check reinforces the feel in their hands and memory. Before long, they’ll throw evenly more consistently from the start, trim less overall, and phase out the tacks entirely as proficiency takes over.
I can’t remember who first taught me this trick. It could have been any one of the many inspirational potters I’ve encountered along my journey in clay. Whoever it was—thank you.
Follow Ferguson on Instagram @aw_ferg.
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