Foot Fetish

About two years ago, I stumbled upon a new process. I bought a cup from my friend Sebastian Moh, and was delighted with the attention paid to the foot. It was very smooth, and I found myself idly rubbing it during use. I asked what he used, and it turned out that he would sand with regular sand paper in a progression from 200 to 1500. I decided to give it a shot on mine, the results were enough of an improvement that I decided to give that sort of attention to all of them. Little did I know at the time, this would awake an obsession.

I devoted a lot of time and resources in the months to follow finding a way to polish the perfect foot. The result at this point is a foot ring that shines like glass, and glides across a table in a wonderful way. The sound and feel when it touches down on a table is distinctly different from that of an unpolished foot – a solid and resonating clank versus a dull thud. All the work I put into my pots are to the end of having an object that screams luxury. Once I got one foot to shine like glass, I soon realized that I would never send out another one that didn’t. Now that I have it all figured out, I thought why not share what I’ve learned?

It began with a trip to a local hardware store to get every grade of sandpaper I could. I sanded with 200, 400, 800, and 1500. I beleive that these numbers correspond to the mesh size of the sanding medium – it has passed through a screen with that many threads per square inch. The bigger the number, the finer the particles, just like clay materials. The sandpaper was wet/dry silicon carbide, made for sanding metal. It worked OK, but the sandpaper wore out really quickly, and there was not much bite to it. It is only marginally harder than the porcelain, so it took a lot of sanding to little effect. I knew there had to be something better out there, so I researched a bit more.


I stumbled across a store called, which specializes in diamond abrasives for various purposes, largely in polishing stone countertops and floors. I thought that if their tools can grind stone, they can probably cut through porcelain (being synthetic stone, technically) pretty effectively. I began with a set of diamond hand pads. I had a batch of work to send out to AKAR in Iowa City, and thought what better opportunity to try this process? One thing I learned right away is that the diamonds are not nearly as forgiving as sandpaper. If you even touch them to the glaze, they will scratch it, so I had a few pieces to refire right away. The set I bought went to 3000 grit, and at that point, I discovered, the foot begins to shine. This was my first moment of discovery. The grouping of about 20 pots took me 8 hours to do. I knew I had to have this finish, and also knew I had to figure out a more efficient way to do it or I’d never make all my deadlines. I went back to toolocity to find a power tool.


I decided on this Gison Wet Air Grinder from the same site. The first pads I tried were a disaster, wearing out almost immediately. I went for a set that were bigger and also meant specifically for wet sanding. They were spectacular and have lasted for more than 2 years!


The tool itself works by an pneumatic piston, and at the same time, showers water out of the middle. It needs to be hooked up to a hose, which will require a run to the hardware store. While you’re there, make sure to get whatever you might need to hook it to a compressor. The thing does require more air than a small hobby type compressor can provide to run continuously, so keep that in mind before you buy. I then Velcro strapped it onto a chunk of wood. I found that it works best to mount the tool upside down and then It took a bit of practice to figure out how to use. It should be inside a sink or bin with a drain, as it will fling water constantly for as long as you are using it.

grinder in use

Thanks for reading and I hope you find this info useful!


  1. michael says:

    I love the diamond “sponges”. I used them recently on some swirlware bisque and was amazed on the details that they brought out of the colored clays.

  2. Patty rios says:

    Are you wearing a mask? I suppose that all the water keeps the particles that are removed by sanding from freely floating and being inhaled. I used to grind fused glass and the grinder kept flinging water and glass towards my face. The instructor never said anything about protection I hate to think about how much glass I probably inhaled before the lightbulb went off. I have always admired your work and now with the polished glass bottoms they are truly a thing of beauty and there is something to be said about the polishing experience. I find it very zen like.

  3. Diane McNeil says:

    Thanks, Jeff. This was great information. It’s inspired us to go further on our foot fetish quest.

  4. Lori Buff says:

    Hi Jeff,
    Great article, thanks. I have a mug with a beautifully finished foot and love the feel of it so I understand your desire to create the same.
    Are you now sanding only with the 3000 grit or do you build up to that and are you using any final buffing pads?
    Thanks again,

  5. Kristin says:

    Incredible. And so generous of you to share the process. Do you work through each pad in the set for every pot?

  6. Sara N says:

    I have those same grinders. I use them for making neat patterns on my clay. I didn’t know that they were for what you described. My luck! I have twenty! and will try them next!

  7. Zac Hould says:

    Hello Jeff,

    Was glad that to see you posted this because a few weeks ago I was looking all over online if I could find ANYTHING on Sebastian but came up empty. First, I tried a new method last month on 50 or so pots. The latest firing I had was in someone else’s kiln so I had two problem, lots of uneven foots and then sticking that left a few pieces with chunks of foot missing. Most were Coleman porcelain to cone 10 but I way started with a smaller Dremel bit and one larger. This works for me since I trim the foots to come to a points and there is nothing round on the foot.

    Then I would use the 3M wet/dry silican carbide sandpaper. I would start with p-800, then 1000 grit, then 1500 grit, and then with 2000 grit. I then used a Norton Water or Wet stone that is a 2 sided brick. One side is a 4000 grit and opposite is an 8000 and they suggest a 10min soak in water prior to use. The stone was $99 and they are used for sharpening knives and shaving straight razors. If you think 8000 is high, they do have 10,000, 12,000, 16,000, and as high as 32,000. Those are similar to the diamond blocks you had pictures of. If you are curious about these, try this site:

    I still need to find a fair amount of circular motions or use a pattern of going back on forth on the 2 final grits. Here is an article that may be of interest or completely disregardable but some info on use of high grits:

    One last thing, these people that sharpen there razors actually will finish with chrome oxide for a nice smooth edge, eh, kind of interesting. Thanks again for thorough posts and cheers to your new, clean, sleek and slick looking website.

    Best Regards from Los Angeles,

  8. Jeff Campana says:

    Thanks everyone for your comments. Yes, I do indeed go through each pad (200, 400, 800, 1500, 3000, buff) on each pot. That’s the only way to get it super shiny. Skipping steps has proven not to work to the level I am going for. That’s not to say that everyone needs to take it to that level. Even a quick pass with just the 400 makes the foot smoother than most out there.

    About dust – there is none. All of the dust is thoroughly drenched as it is formed. Then it goes down the drain.

  9. Wes Stack says:

    Ordered and received the Gison GPW-7. Am having a difficult time finding an air hose solution. I see in your last photo that you seem to have put together an adapter, but it’s hard to see exactly what you did. Please let me know how you handled both ends and which hose you purchased. I’ve been to both Lowe’s and Home Depot with no luck. Thanks and thanks for you post. Am anxious to get this thing working.

    Wes Stack

  10. Jeff Campana says:

    It’s hard to say exactly what you should use, as I don’t know what size of air hose fittings and faucet fittings you may be dealing with in your studio, but I would recommend removing parts of those things and bringing the grinder and the ends that you need to connect it to into a small locally owned mom and pop hardware store. Often employees of these places will be more than happy to figure the whole thing out for you, and write up a list of the parts that you bought. The big box stores have neither the flexibility to open and try various parts, nor the expertise and engagement of employees to actually help you navigate the mondboggling inventory. It is all stuff that any hardware store carries in their plumbing and pneumatic sections.

  11. Valerie says:

    You have been a constant source of information and inspiration for me and I appreciate your generosity with sharing your knowledge and passion.
    I’ve been very pleased with the results of the diamond pads, though labor intensive … but excited to report that there was a Gison wet air grinder under the Christmas tree and I can’t wait to use it!
    Thanks for everything Jeff!

  12. Judy Thompsom says:

    Jeff, As always you have a wealth of information that you are always willing to share. With novice potters like me I am always very thankful. Hope your new adventures since the Bray are great!

  13. Lorraine says:

    Couple things. Could one use ones pottery wheel to mount the sanding discs instead of purchasing the grinder? It does go round and round! You would have to add a water source.
    I have applied t-sig to the bottoms of pots and polished it to a nice shine with plastic bags. It feels great although the higher the firing the less shine, tho I feel it still is as smooth. just an idea.

  14. Hi Jeff. Thanks for your post. I have been using those diamond pads you are using for years and they are a game changer for sure. The air powered tool looks like a great step up and I’ll be looking into it for an addition to our studio set up.

    All the best,


  15. Donn Buchfinck says:

    Hi,A good idea is to use a sheet of glass with varying grits of silicon carbide to grind with water. You can take it right down to the glass state real quick.
    Also a wet vertical sander will do the job also, $300-800 for a tabletop model.

  16. Good to find your blog Jeff. I am also sanding my ^10 porcelain after it’s been fired to get a nice satin finish. I’ve been using 400 grit diamond pads on the bottoms as well as exterior walls. Lately I started looking into power tools that may do the job for me as my thin translucent vessels becomes larger. I talked to some glass artists, but did not make any decision yet o what to buy. Will go explore some of the options mentioned here.
    Best wishes.

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