Evening out (already fired) wobbly foot ring

[petrichor 1]

Hello!

I recently started making some wider bowls, and thus wider foot rings. For some reason, som of these bowls came out with a slightly wobbly foot ring (the width is not the problem, it is just not 100% flat). Never had this problem before, but I suppose I just have to do a better job when trimming. Anyways, there would be such a shame to discard these slightly wobbly bowls: is there a way to flatten the foot rings? It is stoneware, so I suppose regular sand paper would not get me very far. Would be super thankful for any help!

[Cline Campbell Pottery 7]

Try wet-dry sandpaper.  Glue it to a very flat surface with waterproof glue.  Hold the bowl by the sides and move it in circles on the paper.  Use the paper wet to avoid dust.  There is also sticky paper you can stick to your wheel.  Or you could glue your paper to a bat.  But you  may find it hard to to hold the bowl when you use a machine.

Cynthia

[Callie Beller Diesel 2,775]

How wide are we talking? Did the middle part of the bowl slump, turning it into a rocker or a spinner? If so, adding a second inner ring, or leaving a flat plaque in the middle could help.

If you can get diamond sanding pads, they’d work better than just wet-dry sandpaper. It might just be faster to re-make them though.

 

[Piedmont Pottery 35]

Diamond disks attached to a bat work well for this.  They are available in different grits, I have an assortment that I use for polishing the bottoms of macrocrystalline glazed pots.  Be sure to keep the diamond disk surface wet at all times while polishing to minimize the ground clay particles from becoming airborne, and to make your diamond disk last longer.  

[CactusPots 264]

A diamond disk  on a plexi bat on the potters wheel head with a water drip is well worth the trouble to set up.  The diamond head when kept wet lasts a really long time.  I put a drain to bucket in the catch pan.  Live by the runny glaze.

[liambesaw 2,966]

I use a 12 inch lapidary disc fixed to a bat.  Cheaper than the pottery specific ones by at least half.

If you have amazon or ebay search for 8 inch 240 grit for a cheap one or 12 inch for a pricier one that can do larger feet.  

I use 60 grit for really taking them down but 240 is a nice smooth finish that won't scratch furniture 

Edited April 7 by liambesaw

[Magnolia Mud Research 749]

12 hours ago, petrichor said:

For some reason, som of these bowls came out with a slightly wobbly foot ring (the width is not the problem, it is just not 100% flat).

Some questions:
1. are the bowls stable (don't wobble) at the trimmed and bone dry stages prior to being fired?
2. are the bowls stable after the bisque firing?
3. or are the bowls only wobbling after the glaze firing? 
the answers to the to these questions will give you some insight as to where the wobbling originates.  

you mention that your trimming of the bowls might be a cause, check immediately after the trimming.  I have used a flat board to check stability for my ware at both leather hard and bone dry before sending to the bisque kiln.  

If the wobble comes only after the glaze firing, check to see your kiln shelf surface is flat.  

LT

[petrichor 1]

Thanks for all of the tips! I think I´ll go for a disc. Very helpful as always, I appreciate all answers!

 

So, the bowls are stable after I have trimmed them, and I always test them on a flat board before glaze fire. Most are okay, but some of them get a slight wobble. This never happens to my smaller bowls or tea bowls. I might try a double ring, yes!