Introduction: Trimming a Pot 101

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So you made a bowl on the wheel from the Throwing a Pot 101 Instructable!? Nice Job! Once it has dried out for maybe about 12 hours or so it will become leather hard. You will know it is leather heard because it will be firm, but still cold to the touch because it has water left in it. This is the optimal time to finish the outside shape.

If you take a look at your pot, you may notice the outside shape does not resemble that beautiful inside craftsmanship you so diligently fussed over. Your little bowl probably feels pretty heavy for its size and looks fairly unrefined from the outside... dare I say a bit ugly?!

Trimming or Turning as it is traditionally called from way back in the day will give you the opportunity to remove any excess clay and further shape your piece to reflect a shape similar to the inner beauty of your pot.

You Will Need:

  • Trimming Tool
  • Needle tool
  • Sponge
  • Bucket of water
  • Small ball of extra clay

Step 1: Measure the Bottom Thickness

  • Poke through the thinnest area in the bottom of your pot.
  • Follow your index finger down to where the base of the clay meets the needle tool and pull up. This is the bottom thickness.
  • Press the measurement at the end of the needle tool into a small piece of extra clay so you can view it later on.
  • Use a tiny amount of water on your finger and some elbow grease to seal the tiny pin hole up.
  • Take a moment to feel around your piece to get an idea of the thickness of your walls. Are there some areas that are very thin that you should take note of? What is the thickness of the walls where the base and sidewall meet? Having an idea of this will give you a bit of a guide as to how much you will be able to trim away in certain places.

Step 2: Measure the Interior Base Width

  • Use fingers to measure where the wall and base of the pot meet in the inside.
  • Carefully flip your piece upside down and place your fingers on the bottom holding the measurement you took.
  • Make a notch in the clay with your needle tool on the outside of your fingers to mark the measurement.

Step 3: Centering With the Scratch Method

In order to trim your piece you have to return it to the center as best as possible. If your piece is not symmetrical you will have to do your best to get it as close to centered as possible. Remember these are HAND MADE so don't be so hard on yourself! But also, you find trimming to be not that enjoyable so don't just be lazy about finding the center either.

  • With your piece upside down, eyeball center which ever concentric ring it fits best into on the wheel head.
  • Hold needle tool with both hands resting on splash pan in front of your bellybutton.
  • Spin very slowly. Carefully bring the very tip of needle tool straight forward towards the highest inch or so of your piece.
  • Allow the needle to scratch lightly against the wall for a few rotations. If your piece is moving as you try this you are push the tool too hard. You may find it isn't scratching all the way around and that is ok.
  • Stop the wheel. Find where the scratch begins and ends by manually moving the wheel head (not your pot!!).
  • Adjust the wheel so the the center of the scratch on the pot directly in front of you.
  • Gently push the pot slightly away from you . This will push the side that did not get scratched to stick further out thus making it more evenly placed in the center of the wheel.
  • Spin the wheel again and start another scratch line below the one you just made. This will help you keep track of what you are looking at.

Your pot is centered when there is a full circle scratched all the way around. Keep repeating the steps until you get it centered.

Step 4: Anchor Pot to the Wheel

  • Roll extra clay into 4-8 pieces depending on the size and shape.

-If your pot is very shallow you will want smaller balls of clay so you can trim further down the side.

- If your pot is taller you will want larger balls to support higher up the side of the piece.

-If the rim of your pot is narrower than the rest of the pot then you will want to make sure the clay supports all the way around. Rolling a coil shape for attaching would be better in this case.

  • Hold your left hand firmly on the bottom of the pot as you slowly push a ball of clay at a 45° angle where the rim of piece and the wheel head meet on the right side of the piece.
  • Manually rotate the wheel 180° and repeat above step. Continue adding anchor clay until the pot is attached evenly on at least 4 sides if not more.
  • If at any point your piece moves as you are attaching the clay it is best to remove all anchors and repeat step #3 to re-center the piece.

Step 5: Draw a Circle Guide

  • Hold your needle tool with both hands at 3 o’clock.
  • Spin the wheel slowly and wait until the notch you drew from step 2 comes around.
  • Apply the needle tool down onto the pot and create a circle.

This will be the guide for how far to trim inward at the bottom edge of the pot.

Step 6: Hand Placement

  • It is usually best to hold the round or square side of trimming tool with your index finger in front, and three fingers wrapped behind.
  • The grip should be firm, but your wrist soft/flexible for contouring the outside shape to match the inside shape.
  • Left hand should be resting gently on center of clay. Hands are connected in some way- thumb/thumb, left thumb/right index finger, index finger/index finger, etc. This will allow greater control when you start to trim.

Step 7: Trimming the Excess Bottom Clay

  • Focusing the cutting coming from the top rounded area of the loop side.
  • Start on highest edge of your piece. Spin the wheel a medium fast speed, and apply the tool down at a 45° angle.
  • Slowly contour your hand up and down the side trimming in towards the circle you drew.

*Remember go slow with your hands, and fast with the wheel.

  • If the wheel is going too slow you will gouge your piece.
  • If your hands are moving to fast you will create uneven swirl patterns on the outside.
  • Spirals of clay should be removed and a general bowl shape will start to form on the outside. Stop when you get to the circle.

Step 8: Cutting the Foot

  • Swap to the square side of the tool. Hold the same before.
  • Focus the cut coming from the center of the top blade between the corners (See first picture in this step.
  • Spin the wheel. Hold the tool at a 45° on the new top edge.
  • Apply on the right corner of the square side of the tool down into the pot. Once an even ridge has formed tuck that right corner down and in towards center of the pot to cut the edge of the foot.

From here you will have a bit an extra ridge that has formed just to the outside of the foot.

  • Swap back to the round side of the tool and blend the edge so there is a nice transition from wall to foot (See previous step).

Step 9: Measure the Inside Foot

  • Place the square edge of your trimming tool on the edge of your pot.
  • Mark a line with the needled tool and drawl a circle guide.

This time you will be trimming the inside area away.

Step 10: Trimming the Bottom

Take a look at the measurement of the bottom depth you took at the beginning. Generally speaking you want to trim about half the thickness away.

  • Hold the square side of tool with fingers in front and thumbs in back... Like you are playing a recorder. Remember those things?!
  • Spin the wheel. Start at 3 o’clock on the new circle guide. Focus slight pressure on right corner to create a groove.
  • Even out the pressure so the long edge of the blade is being used in the center to prevent adding extra ridges as you trim.
  • Work horizontally (left) from 3 o'clock inward through center and then back out to where the inner edge of your foot starts.
  • Repeat until you have removed about half the bottom thickness.

Step 11: Finishing & Admiring

  • Run the square side of the trimming tool on the edges of the foot inside and out to soften it slightly.
  • Use the square side of the tool to clean up any ridge marks along the side of your pot. Focus the pressure on the center of the blade to prevent further marking.
  • Carefully remove your pot from the wheel.
  • Sponge any areas that are rough. Don't forget to sign the bottom of your piece. Hold it carefully from the bottom, never from the sides while you smittenly admire your piece...Yeah you made that! No big deal or anything.