Studio Design

[hitchmss]

@glazenerd I have thought about my future needs of the building. Plan on myself primarily for the next 2-3 years with a part time assistant or shared space potter. At the very max I would have 1 full time assistant and 1-2 part timer. Have planned space to allow for slip casting work and ram press as money becomes available. Likewise, am planning on the two electric kilns I have now, the one gas kiln, and a future soda kiln. I will put in enough amperage to allow for a potential third electric kiln, and enough gas service for a larger reduction kiln. Current kiln runs on two big bertha burners (500,000 btuh), and soda kiln will run on the same. Likely Id never, or rarely be firing both gas kilns at same time; not only will I have to consider the amount of fuel my line can carry, but the drop in tank temperature and potential freeze up. Current tank is a 500 gallon and has never even developed a hint of frost even when at low fuel volumes; two kilns at the same time, I would imagine Id have to switch to a 1,000. Ive also read about a device (cant recall name) that allows for the phase change from liquid to gas to occur inside a seperate tube which is more able to deal with the drop in temperature; was told that in extreme cold climates, that this is basically standard practice. Good to know that the fuel lines are to be installed on the cord of the truss; works perfectly for my building design!

The county where this will be built has just about outlawed (due to stringency restrictions) leach field septic systems unless you are one of the lucky few who do have the proper soil to support a leach field. Otherwise it has to be a mound, which blows my budget up. Thankfully, soil engineer confirmed yesterday that soils are good for a leach system. Ohio code requires that any floor drain, under roof, be on a dedicated holding tank (for septic systems, city sewer requires oil interceptor). Depending on how long it takes me to hose down each room, and how frequently, a 500 gallon tank may fill quite rapidly. I didnt know that the max was around 500 gallons; was hoping to go larger, so I wouldnt have to drain tank as frequently.

Was planning on having electrical service for the centers of my room; at least two per room on cord winders; not sure if they make hardwired versions for the winders, or if they are all supposed to be plugged in, but was hoping to hard wire.

Im with you on the ADA thresholds already; rolling anything, whether its a ton of clay, or a cart full of bone dry work, across any kind of bump is no bueno!

Was hoping to install main elec service in the kiln room; wanted to have my runs of #6 wire as short as possible. Shut offs at the kilns are a given, and plan on having an emergency shut off for the gas at the door to the kiln room. If I have to install main in another location, It will be cheaper to run (1) #2/#0/#00 or so line for a sub panel, than (3) #6's. I dont fire to anything more than bisque temps in my electric kilns, but I want to wire them as if I were going to take them to my max temp.

Ive spoken with the chief inspector for this county regarding building use; if we were building a commercial grade building, I would HAVE to install a fire detection/suppression system which from what I know about the prices of these systems, would likely be entirely unfeasible. A friend who is now retired, but was a contractor, and consultant later in life, told me that the test, performed at the city tap, for both water pressure, and flow rate, is more expensive than I can imagine.

@neilestrick Chief inspector told me that I have to meet single family residential code, and "whatever I do inside my building, is my own business". The township where this will be located has no zoning, so the use of the land is open, but the building still has to meet its intended uses' code. We will meet as much commercial code as we can afford, but the suppression system is one that Im fairly confident we cant afford to meet. Im also not the kind of business which performs much retail activity (open house 1-2 times a year), doesnt take deliveries all day every day, or perform activities outdoors which would raise questions, and cause inspectors to search for issues. Not wanting to "hide" things from the county, but just cant afford a commercial coded building.

The website info for the exterior sheathing panels by certain-teed are too, only water resistant. As long as its not ridiculously more expensive than greenboard I will install it for the bottom 4' of my wet rooms, as it does have better water resistance than greenboard, and will be getting covered by the FRP anyways. Its a great tip!

[glazenerd]

Hitch:

you are asking the right questions and checking codes-smart!  So I will retire to my recliner, and begin my two hour study of the back of my eyelids. 

T

[neilestrick]

@hitchmss It sounds like you've done your homework, and we should all just sit back and watch this thing happen!

[hitchmss]

9 minutes ago, neilestrick said:

It sounds like you've done your homework, and we should all just sit back and watch this thing happen!

@neilestrick and @glazenerd. I really appreciate the input from both of you; you both brought up a lot of detail oriented questions which are things I was hoping would be brought up in this posting. I hope you dont take my responses as dismissive of your opinions!

I have done a lot of research into this project, but that by no means that what Ive researched is correct, or the best method. I always value a second opinion! There are just TONS of little details which easily get overlooked in a project of this size; anyone who hasnt gone through a custom home build, or a studio build (which I think is more difficult; not only has to look good, but needs to WORK well!) doesnt understand how much goes into something like this. Hence, all you brilliant folks who have made all my mistakes for me already....hopefully...

[neilestrick]

7 minutes ago, hitchmss said:

 I hope you dont take my responses as dismissive of your opinions!

 

Not at all!

[Mark C.]

Leach fields are way less costly than mound sytems( I was involved with a mound system and a back up mound field  needed as well-same with a leach field) in a home building spec house back in the 90s with two other partners. I did the electrical/ mechanical /plumbing/ as well as some framing /wood work. I made $107.perhour after a one year deal. Live and learn.

[glazenerd]

So after spending some time with Mrs. Folgers.

Hitch: a planning trick I teach new home buyers.

draw out each work room on 1/4" graph paper: 1/4" = 1' . Measure the foot print of wheels, slab rollers, kilns, etc. a potters wheel would be 2' x3' of floor space for example. Measure on 1/4" graph paper, cut out each item and either color them or write on them. Use your cut outs to lay out on your room graph. Now you have a visual of how they ( and you) will function in the space. Do not drive yourself crazy by trying to cut 31.5 x 22.3: round up- make life simple.

T

 

[oldlady]

recently saw the classroom that was being built at a local clay school.   noticed that the kiln room was only going to be 4 feet wide by 12 or so.  mentioned having no room to load and the next time i saw it, the wall had been moved to fit a person and the shelving unit.  

saw my idea on this old house last week.   when i built a house i always marked the floor to show stud placement  and adjusted the studs for the plumbing so the stacks fit between studs and the plumber did not have to cut anything.  adding a stud to make up the 16 on center rule was no problem at that stage.  avoid all that by placing the john far enough from the wall so it lands in the center of that stud space and you have room to clean around it.

nice that you can get so many ideas from such a diverse group.

[hitchmss]

@glazenerd I was going to attach a drawing I did, on graph paper, just like you say, showing all my tools/equipment/display/shelving............ Thats exactly how I developed this foot print size for my building. I laid out what I had, and where I wanted it, then added in 3' walkways in between everything, and then adjusted for space to grow. It is an extremely helpful method! Theres a lot of "stuff" which needs a home in a studio; I took one day and walked through and just wrote down what was in both studios and worked up a list of what I needed to have, and what I wanted to have. Helpful in determining what all you need to account for when laying it out.

@oldlady Thats the other aspect that can get overlooked when laying out spaces; how does a human function in the space. Like you say, you never realize how having enough room to clean around a toilet is critical to design, until you dont have the proper room. Ive spent a lot of time measuring my walkways in the studio, measuring heights of things, taking all kinds of measurements. Tried to keep all that in mind when designing this space. I actually took a 3' stick and held it in the center of my body and walked through the studio to see how I navigated through my spaces; was I bumping into everything? What about when making turns, do I need to keep shelving no more than 2' deep because otherwise Ill run into it? Stuff that is hard to predict unless you can simulate it in other spaces. Having worked in numerous other studios, Ive also experienced a lot of cruddy designs/layouts, which helped me to inform what I truly wanted.

It is nice; there are a lot of folks who have a broad range of experiences and backgrounds, from potters, engineers, contractors, teachers...................We all bring our own unique set of skills to the table which is what makes a forum great; a finely tuned sounding board!

[Stephen]

OK I will add one more thought. One thing I have learned in my 59 years of spending quality time with myself is that forward motion on a project I'm working on  will often tend to grow the scope of a project as I put it together and bring it into focus. Now might be a great time to spread it all out and make sure that the project in its entirety after beating up all the different areas is what you wanted to end up with in the beginning. I tend to go bigger, nicer everything when planning and I assume others here can relate. One reason I don't want to build a custom home is that I know my wife and it will take a 450k house plan and turn it into a 650k kick-a$$ house, one chandelier at a time.  

[Mark C.]

On 1/17/2019 at 2:55 PM, glazenerd said:

So after spending some time with Mrs. Folgers.

Hitch: a planning trick I teach new home buyers.

draw out each work room on 1/4" graph paper: 1/4" = 1' . Measure the foot print of wheels, slab rollers, kilns, etc. a potters wheel would be 2' x3' of floor space for example. Measure on 1/4" graph paper, cut out each item and either color them or write on them. Use your cut outs to lay out on your room graph. Now you have a visual of how they ( and you) will function in the space. Do not drive yourself crazy by trying to cut 31.5 x 22.3: round up- make life simple.

T

 

Tom you need to drink better coffee (Folgers)-get yourself a burr grinder and some fresly roasted beans and a clever dripper and have at it my friend-morning will be like a whole new thing for you.

Warning This is a true story about a Folgers drinker. He was a friend of mine ( long gone from this planet) .He taught me a few old school skills and so when He was doing a addition to his living room his contractor (friend of mine) called  me and asked if I could do the electrical. I said yes under one condition and that it was going to be at NO cost to Grover. He agreed and I did that job as a favor. During the short time everyday  at lunch I would walk down the street to a coffee house for real coffee . Grover drank Mrs Folgers which I always turned down as they offered me it everyday (life is to short for bad coffee) One day he said at lunch I;ll go down with you and have some good coffee. He tried to order the same as my order and I intervened and said no he could only have one shot of expresso.

The next day when I came to work his wife was a bit upset and said what did you give him yesterday as he has been awake all night.I said an expresso coffee. So they both learned that Mrs Folgers has very little caffeine in it . Its more of a suggestion of coffee than real coffee.

Just saying -

[liambesaw]

7 minutes ago, Mark C. said:

Tom you need to drink better coffee (Folgers)-get yourself a burr grinder and some fresly roasted beans and a clever dripper and have at it my friend-morning will be like a whole new thing for you.

Warning This is a true story about a Folgers drinker. He was a friend of mine ( long gone to this planet) .He taught me a few old school skills and so when He was doing a addition to his living room his contractor (friend of mine) called  me and asked if I could do the electrical. I said yes under one condition and that it was going to be at NO cost to Grover. He agreed and I did that job as a favor. During the short time everyday  at lunch I would walk down the street to a coffee house for real coffee . Grover drank Mrs Folgers which I always turned down as they offered me it everyday (life is to short for bad coffee) One day he said at lunch I;ll go down with you and have some good coffee. He tried to order the same as my order and I intervened and said no he could only have one shot of expresso.

The next day when I came to work his wife was a bit upset and said what did you give him yesterday as he has been awake all night.I said an expresso coffee. So they both learned that Mrs Folgers has very little caffeine in it . Its more of a suggestion of coffee than real coffee.

Just saying -

I don't know about that, from what I've heard it's the best part of waking up 

[Mark C.]

Hitch can you explain your sanding every pot thing and why that has to happen??

 

[hitchmss]

1 hour ago, Mark C. said:

Hitch can you explain your sanding every pot thing and why that has to happen??

 

Sure Mark, I sand all my pots; all the fingerprints, burrs, boogers, etc that are left on the pot. Some of it is cleaned up when the pot is leather hard with a damp sponge, but a lot of the textures I put on my pot would be smeared away completely If I tried to remove the boogers from these areas, at this time, with a wet sponge. Likewise all my handles are easier to touch up when they are bone dry vs leather hard.  So instead, I use a green scotch brite pad, and the pot gets sanded to remove blemishes.

The sanding is done in a downdraft sanding booth, which has a HEPA filter on it, and of course  a respirator worn while doing this; I also have a very large HEPA filter unit which runs in my studio to filter the air too, in case any dust is escaping the booth, at the same time, and also during normal studio practice. This is much preferred instead of standing in front of a big fan outside...especially in winter.....that was COLD!

A lot of my pots dont get their bottoms trimmed either, and instead of having a separate step in my process where I would burnish the bottoms with a rib, I just use a sanding block, followed up with the scotch pad and its baby bottom smooth.

I dont sand every square inch of the pot, just the areas that need touched up....I guess Im kind of anal about my surfaces....I know a lot of potters don't sand their pots at all. The least amount of sanding I can do, the better as its a process which more than likely only I, or another potter would notice the difference it makes. Its also my LEAST favorite part of the process.

With the new studio, instead of filtering my air with the sanding table's HEPA filter (as I do now), I will just blow it all outside. That's why the sanding room/spray booth room is a separate room; It needs to have its own makeup air to properly exhaust, and in the dead of winter, any bit of heat I will have in that room will be blown outside in about 1 minute. In the summer it will probably be quite breezy and comfortable with no AC! Ill have a fan mounted on the roof of the building which will pump in the same amount of CFM as Im exhausting.

The sanding table is basically a heavy duty furnace blower in a housing, with space for a filter, and a heavy duty grate/working surface (designed for metal workers) and it likely moves around 1400 CFM @ 0.0 IWG; I will also be adding in another dust control system to be used in tandem which pulls nearly 2,000 CFM @ 0.0 IWG (at blower intake port), so combined I will likely have something like 2700-3000 CFM being pulled through the sanding booth. With the room having 900 cubic feet, I will be able to entirely exhaust every inch of air from the room in about 25 seconds or less. To be able to exchange the air in this room 3 times per minute, makes me feel very good about my dust control for this stage of the process.

The new dust control system will be a CVMAX cyclonic filter system; While I could filter the air, I will just be blowing all my exhaust to the outside; this system is used by a lot of woodworkers, which means they need not only a lot of CFM but a lot of velocity too; there will likely be enough velocity to suck any small pots that arent held firmly in your hands, right out of your hands. Thankfully, an all metal impeller (designed to handle wood chunks/chips) would just chew a piece of bone ware right up and out the system. Ill be making a shallow box, with a "V" shape to the bottom which will sit on the grate of my downdraft sanding table and will cover the surface except for a 2" perimeter, to which the CVMAX will be hooked into. It will be the workhorse in removing the vast majority of the dust, and then the blower in the sanding table itself, will just pick up any dust which makes it airborne, before it has a chance to escape the sanding booth.

My Spray booth is a home built one using old furnace blowers, and 12" ductwork. I basically made a large box into which 4 blower motors were mounted, and the box was ducted to the spray booth. The 4 blowers provide a pretty good amount of CFM on the 12" duct (biggest we could fit into current studio), but with the new studio, I will be upgrading to a 16" duct, which should increase my CFM by a bunch! The spray booth's exhaust ports are on the top (a wye splits the main trunk into 2) so they can catch the over spray as it bounces off the bottom of the spray booth, up the back wall, leading into the ports. With this new CVMAX I'll be adding a 10" port dead center at the back/bottom of the spray booth which will capture most of the overspray, and any that lingers, will be picked up by the blowers. 
Im no engineer, but hopefully my addition of the new exhaust system, done in the manner which I am describing, does not create too much turbulence and actually decrease my airflow. I guess once I get it installed Ill be able to tweak the sizing of the ducts, and use dampers to fine tune so I have the optimal exhaust.  Blast gates installed at both devices will allow me to isolate my exhaust too so Im not getting blow back.

I will have infrared heaters mounted on the wall to the left/right/above the sanding booth/spray booth so that Im not entirely frozen during the winter (infrared heats objects, not air).

[hitchmss]

2 hours ago, Mark C. said:

why that has to happen??

I guess it doesnt; but I dont like boogers on my pots.

[neilestrick]

I think you could change your throwing and trimming techniques just a little and do away with sanding altogether. It'll save you money on the build, save your lungs, save electricity, save space, etc. I have to have very smooth surfaces for my decorating techniques, and I never sand anything.

[Mark C.]

I was thinking as a full timer that try to eliminate as much as yiou can the sanding steps will save you so much time.We all have our ways and its hard to change them unless we see a real gain. I'm just suggesting a looks see . Any one or two extra steps is alot with high volumes you ands I produce. 

Its like sparying of glazes vs dipping -spraying just takes longer. The effects are different in spraded glazes but it takes longer .

The same would be true with sanding. I used to sand most pots(with the green and brown pads and sand paper) when I started but saw another potter wet sponging and I took off with that  idea and I do very little sanding now with my porcelain.Sure now and gagin a pot slips thru and needs it.

Sounds like the downdraft table works well with that I was just thinking about all that time used in the process.

It really does not matter whio we get to a smooth glaze pot for the public to buy-its the time it takes to get it done.I think your process could be tweeked to save you some time thats all.I tend to wet sponge most pots that need it when loading my bisque. I tend to sponge them when I move them.They are in my hand and its fast and not a seperate process than.

Just consider a process change and see if that saves time -keep an open mind about that change and see if it can work for you.

[hitchmss]

30 minutes ago, Mark C. said:

Just consider a process change and see if that saves time -keep an open mind about that change and see if it can work for you

 I agree wholeheartedly with this, and the same thoughts from @neilestrick. My throwing and trimming are clean; most pots are ribbed down on the surfaces, rims, and feet are lighlty sponged while throwing. Trimmed feet are burnished with a finger, and any "larger" splats/boogers are shaved off with a trimming tool while ive got the pot in hand. For the pots which dont get trimmed, the bottoms need to be touched up quickly to remove any boogers from the wire, or being moved around while soft; I could do this with a rib, but kind of like what you are saying, adding in another step becomes a pain. A lot of my pots have textures(i use a toothed rib to make swirls, pencil sharpeners, that kind of thing)  which a wet sponge will smear the surface too much at leather hard or softer stages. Pots which get handles (which are a bunch), are cleaned up with a damp sponge when handles are put on, but there's always some more cleanup needed on the handle, which cant happen until the handle is firmer (I attach softer than leather hard).

More than anything, its the pots which have holes drilled into them, or are cut/altered, which need the most attention; also, almost all of my pots get lifted off the wheel after throwing and onto ware boards; because of this, there are always "slippy" fingerprints. I try to time drilling holes so the clay is as close to leather hard as possible, and use a sharp drill, so the burr is as minimal as possible, but sometimes impatience, or just lack of ability to get bottoms/tops of pots equally dry means there are going to be some drill goobers left. Usually a trimming tool at bone dry knocks these off with short easy, but I find a quick touch up with a scotch pad at sanding takes care of any sharp edges. Same goes for sponge holders; the cut out areas have been smoothed down with a wet fingertip to knock sharp edge off, but I find they still need a touch up.

For me, with my limited space, I need to get pots made, and stacked up to dry, so that I can move onto the next series of pots. If I tried to add in another stage at leather hard where I was wet sponging all the details up, Id have to try and control my drying a bit more than I do, which is difficult with limited space. Likewise, If I do stack them up, then unstack them to sponge them, it seems to take as much time as I do just sanding them. Im with you Mark about doing it while its in hand, and not making a special job out of it!

I use BMIX, which is not as smooth as porcelain, but pretty darn close; with a sponge, I find the surface to be not as smooth as when I sand it, which is why I prefer to sand. Some of my glazes are translucent (most are relatively opaque) and will show blemishes quite readily; while I could omit sanding on some of the pots which get opaque/thicker glazes, it would be too difficult to keep track of which are which.

I agree that its a pain in my rear,  a waste of time, and while I do try to eliminate as many blemishes as possible prior to sanding, Ive just found it to be a necessary evil. When I had my assistant, a lot of his job was sanding pots, which meant I was paying someone to do it. Now when I dont have a full time assistant, I have a part timer who helps, but I do most of myself. For a 4 week run of pot making, it takes me about 3-4 days to sand everything. Yes, it is 3-4 days which could be much better spent doing something else, but I just havent figured out how to omit it entirely. All in all too, whether or not Im sanding them bone dry with a scotch brite pad, or sponging them with a damp sponge, the time is being spent; I find it easier to just have a mountain of bone dry that gets sanded, and then loaded into the kiln.

 

[Mark C.]

Drilled holes are really as you said only work when dry to clean up. Just a thought on the overall process and saving time in steps.I have worked with b mix myself over the decades . I did not like its drying  abilities nor the cracking on larger work. It does take more glaze than porcelain (thicker application) to get the same results.

[neilestrick]

@hitchmss See my post HERE about dealing with holes. cleans up the hole nicely, no burrs or sponging needed.

[hitchmss]

@Mark C. Im not a huge fan of Bmix myself. Handles with BMIX are a pain in my rear; no matter how well I score, slip, score some more, wiggle together, press firmly, blend, and clean up with a damp sponge, I still have a lot of handles which develop hairline-small cracks. Ive tried drying fast, tried drying slow, doesnt seem to make a big difference. This pertains to mug sized/thick handles; with chunky thrown handles, I can stick them on and forget it.

Likewise, as you said it, on bigger forms, especially flat forms, it is a nightmare to keep from cracking. If I make plates over 12-14" it will take me about a month to slowly dry the plates without risking cracking 40% of them. I too have a fair amount of smaller pots that will develop s-cracks, even though all of them get compressed floors, and the loss rate is less than 2%. Could just be that I didnt compress that specific pot enough, but it makes me wonder what I did different on that pot, vs the other 98 of them. I know Steven Hill talked about not throwing on the spiral from the pug mill, with BMIX because it liked to crack following the pug spiral...may be part of my issue.

The only reason Ive continued to use it, is that there are only two clay manufacturers which are "stocked" in town; Standard and Laguna. Admittedly, I havent looked into either manufacturers porcelain, or white stoneware clays, much. However, with the new studio (space to store 1-2 tons at a time) I will be able to buy clay from any manufacturer and store it. As it is now, I kind of have to use what I have available in town, as I can only store about 1200# in the studio at a time.

What clay do you use? Any recommendations? I like the color and the texture of BMIX, and it throws nicely. If it was a whiter body Id have no issues with that. Currently I pay about $17/box, or $.34/# and would prefer to not spend more than $.50/#. Clay is by far the cheapest resource that I use, but it still adds up when its 8-10 tons. 

[hitchmss]

@neilestrick I saw your post regarding a countersink; heres my issue. Most of my holes are drilled on berry bowls, and my wall thickness on my b-bowls is so thin, that should I countersink the inside/outside of the hole, Id just be making a bigger hole; not enough meat in the wall left to not blow the hole out further. For example, heres a b-bowl I made yesterday. Now, If I were very careful about just barely letting the countersink bite into the clay, it would be a very effective method to clean the holes up, but with 28 holes per bowl, at 30 bowls, that's nearly 900 holes to clean up. If it took me 3 seconds per inside & 3 per outside, per hole, to carefully clean up each hole with a countersink, thats nearly 90 minutes, JUST to countersink all those holes. 3 seconds is probably not a fair assessment either, as it doesn't factor in moving pots to and fro, etc etc. Call it 2 hours to countersink;  would take me half that time to quickly sand all the burrs off.

Not saying that its not an effective method, but with my thin walls, I think it would take me a LOT more time. With thicker walls, one could use a drill/countersink combo, and while drilling the hole, the outer hole edge could be touched up in the same motion; countersink by hand on the inside and it would be done.

On a side note, I often like to crunch numbers on things like the above; how many seconds it takes to do "x" function. When factored into something that is repeated in the thousands, how much time does each task take. Like for example, how much time, do I, each year, spend stamping the bottoms of my pots with my hallmark? 2 seconds per pot, 8,000 pots avg per year, thats 16,000 seconds, divide by 60 seconds , gets 266 minutes, divide by 60 minutes, gets just under 4.5 hours. If it takes 4 seconds instead of 2, it turns into nearly 9 hours. I guess when you have a lot of time to yourself, you think about these silly things.

I ran into someone at one point in time whose occupation was Industrial Optimization; basically, he went into factories, and looked at all these little details like the above; how long did it take the worker to step 5 feet vs 10 feet? and he would show the factories how they could save HUGE money, by doing simple little things, just a few seconds more efficiently. Kind of nuts!

[Mark C.]

I switched long ago to Daves Porcelain (wc384)from Laguna long ago( threw b mix for years long ago)-does everthing b mix does except throw big. I had a few tons made with fine white grog for big pots but gave that up. Now with my petter pugger I can make a batch with a little 1/2 and 1/2  added (wc 382) and that throws big.

I use the 1/2 and 1/2 for slab work-They make two kinds  of this clay so heads up

Babu porcelain (wc428) and #550 (wc 631) I use for small items I want color to pop on as these are very bright white clays

I get the 12 ton price break and buy clay yearly and stockpile it. saves $$$$$

[hitchmss]

3 minutes ago, Mark C. said:

I get the 12 ton price break and buy clay yearly and stockpile it. saves $$$$$

I have built in enough space in the one studio room to store 4 tons there. Depending on how quickly, and thoroughly I fill up the studio, Id probably have enough room to do as you say, and buy clay once per year. As it is now, 10 tons is the most Ive burned through one year, but maybe in the future.

[neilestrick]

@hitchmss It takes less than a second to do each hole. I can do an entire colander in about a minute. Just takes a little twist with the fingers. If the clay is firm enough, it just knocks off the edge, doesn't blow it out. Mine are thin too. Might be worth trying. Plus there's no dust, and makes a better looking hole- no sharp edge.