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#1 jemenfous5

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Posted 28 March 2013 - 09:31 PM

I've been throwing on and off for a few years, and I just recently bought a new brent wheel. I've certainly been able to center and successfully throw basic forms, but for some reason I've been having trouble consistently getting pieces centered and don't know if its me or the wheel. I seem to encounter the most problems when trying to open. I get it seemingly centered, and then as soon as I begin to open up it goes off center. I've tried opening several different ways and it always gets off center. I don't know if its the wheel, or if the clay isn't totally centered before opening, or if I'm opening incorrectly.

Also, does anyone of of a fool-proof way of making sure the lump of clay is perfectly centered before opening. I go by sight and feel, but perhaps there is more exacting method.


Thanks

#2 Benzine

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Posted 29 March 2013 - 08:13 AM

Here's a way.....

http://www.dickblick...kcenter-system/

......Waits for OffCenter.....


Seriously, I too go by sight and feel, and instruct my students to do the same. Once I have it centered, I put both hands on the sides, of the mound of clay, and see if I can feel any lateral motion, "wobble". If I'm really not sure, I'll lean down, to look at the edge, to see if I can see any visual lateral motion.

It could still be, that you are opening off center. I know a lot of people use their thumbs, immediately after centering, but almost always use a single finger, almost parallel to the top of the clay, to "test" my opening point first. If my finger is pulled around, where I rest my finger, that is not the correct point. Once I find that spot, I make a small opening, with a single finger. I then use the two thumbs to widen the opening. However, if you take your thumbs away too quickly, while opening, this can make the opening seem off center. It can be corrected though.

If the whole mound becomes off center, I'm not sure what the cause is.
"Anything worth believing, is worth questioning"

#3 Pres

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Posted 29 March 2013 - 09:08 AM

I've been throwing on and off for a few years, and I just recently bought a new brent wheel. I've certainly been able to center and successfully throw basic forms, but for some reason I've been having trouble consistently getting pieces centered and don't know if its me or the wheel. I seem to encounter the most problems when trying to open. I get it seemingly centered, and then as soon as I begin to open up it goes off center. I've tried opening several different ways and it always gets off center. I don't know if its the wheel, or if the clay isn't totally centered before opening, or if I'm opening incorrectly.

Also, does anyone of of a fool-proof way of making sure the lump of clay is perfectly centered before opening. I go by sight and feel, but perhaps there is more exacting method.


Thanks


Simple test for centered clay-move your needle tool in slowly from the side until it just barely touches the clay. Stop the wheel and check to see how far around the mark goes on the hump of clay-short line very off center as compared to a long line.

Simply retired teacher, not dead, living the dream. on and on and. . . . on. . . .                                                                                 http://picworkspottery.blogspot.com/


#4 OffCenter

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Posted 29 March 2013 - 11:59 AM

Here's a way.....

http://www.dickblick...kcenter-system/

......Waits for OffCenter.....



The only thing worse than a splash pan is a Griffin Grip and the only thing worse than a Griffin Grip is this piece of crap!

Jim
E pur si muove.

"But it does move," said Galileo under his breath.

#5 Nelly

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Posted 29 March 2013 - 03:11 PM


Here's a way.....

http://www.dickblick...kcenter-system/

......Waits for OffCenter.....



The only thing worse than a splash pan is a Griffin Grip and the only thing worse than a Griffin Grip is this piece of crap!

Jim


Dear All,

When I have trouble either centering a piece of seeing that it goes off during throwing I go through a bunch of thought processes... (please feel free to correct me in anyway if I am wrong).

1. Is my wheel level (i.e., has my wheel shifted and is it as close to level as possible using the guage). I use shims or elevate the legs if required to make it level.

2. Have I wedged my clay properly?? Are there lumps or places of air knocking it off??

3. Am I braced in a position where I am almost like a lever going into the clay (i.e., straight and not bent).

4. How is my body positioned vis-a-vis the wheel head?? Am I off too much to the left in my chair or too much to the right??

5. Is my bat really sitting on the wheel pins or is it sitting on the crud of yesterday's throwing??

6. At my age, I now remove my glasses when throwing to see that I am centered. If I didn't, for sure the pile of clay would be off.

7. If I find I am not able to center it I say to myself "hold your hands on either side of the ball of clay and eventually it will right itself."

8. Before starting to center did you hit the clay into a general central position on the wheel head?? This can really start a piece off well as you don't have to fight too much with it to get it to the place you want it to be from the onset.

10. What is my mood?? I find if I am anxious in anyway, it can come out in fighting with the clay.

11. What grip have I used in entering the clay? I like two fingers clasped together and pressing down with my arms braced against my body.

12. Where are my hips as they relate to the wheel head?? Are they slightly above so I am approaching the clay in a top down manner if sitting.

I could go on and on with all my neurotic thinking that I review in centering clay. I must say though, this list has helped me. I am sure there are many different aspects of this process I have forgotten?

If ever a piece that I throw is off and I cannot detect it when I am throwing and it is caught in the trimming process, I simply make the base into a triangular foot. I can cover up a lot of issues with this style of foot ring.

Just my thoughts. Please, anyone, feel free to correct me on any of these points.

Nelly

#6 Nelly

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Posted 29 March 2013 - 03:49 PM



Here's a way.....

http://www.dickblick...kcenter-system/

......Waits for OffCenter.....



The only thing worse than a splash pan is a Griffin Grip and the only thing worse than a Griffin Grip is this piece of crap!

Jim


Dear All,

When I have trouble either centering a piece of seeing that it goes off during throwing I go through a bunch of thought processes... (please feel free to correct me in anyway if I am wrong).

1. Is my wheel level (i.e., has my wheel shifted and is it as close to level as possible using the guage). I use shims or elevate the legs if required to make it level.

2. Have I wedged my clay properly?? Are there lumps or places of air knocking it off??

3. Am I braced in a position where I am almost like a lever going into the clay (i.e., straight and not bent).

4. How is my body positioned vis-a-vis the wheel head?? Am I off too much to the left in my chair or too much to the right??

5. Is my bat really sitting on the wheel pins or is it sitting on the crud of yesterday's throwing??

6. At my age, I now remove my glasses when throwing to see that I am centered. If I didn't, for sure the pile of clay would be off.

7. If I find I am not able to center it I say to myself "hold your hands on either side of the ball of clay and eventually it will right itself."

8. Before starting to center did you hit the clay into a general central position on the wheel head?? This can really start a piece off well as you don't have to fight too much with it to get it to the place you want it to be from the onset.

10. What is my mood?? I find if I am anxious in anyway, it can come out in fighting with the clay.

11. What grip have I used in entering the clay? I like two fingers clasped together and pressing down with my arms braced against my body.

12. Where are my hips as they relate to the wheel head?? Are they slightly above so I am approaching the clay in a top down manner if sitting.

I could go on and on with all my neurotic thinking that I review in centering clay. I must say though, this list has helped me. I am sure there are many different aspects of this process I have forgotten?

If ever a piece that I throw is off and I cannot detect it when I am throwing and it is caught in the trimming process, I simply make the base into a triangular foot. I can cover up a lot of issues with this style of foot ring.

Just my thoughts. Please, anyone, feel free to correct me on any of these points.

Nelly


Dear All,

Just one more thing I forgot on my last post.

13. Did I cone up and then down and then up and then down and maybe a third time?

Nelly

#7 Diane Puckett

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Posted 29 March 2013 - 04:47 PM

When I had a brand new wheel, my plastic bats were too tight for the new bat pins. If the bats are not firmly on the wheel and level, you cannot center. With the wheel spinning, let a wet finger lightly sit near the edge of the bat, and watch to see if it stays level or goes up and down.

If you can remove the bat pins, try throwing with no bat. If you can center and throw a pot with no bat, your bats are probably the problem.

Is there a nearby potter who could try throwing on your wheel?
Diane Puckett
Dry Ridge Pottery

#8 Pres

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Posted 29 March 2013 - 05:09 PM




Here's a way.....

http://www.dickblick...kcenter-system/

......Waits for OffCenter.....



The only thing worse than a splash pan is a Griffin Grip and the only thing worse than a Griffin Grip is this piece of crap!

Jim


Dear All,

When I have trouble either centering a piece of seeing that it goes off during throwing I go through a bunch of thought processes... (please feel free to correct me in anyway if I am wrong).

1. Is my wheel level (i.e., has my wheel shifted and is it as close to level as possible using the guage). I use shims or elevate the legs if required to make it level.

2. Have I wedged my clay properly?? Are there lumps or places of air knocking it off??

3. Am I braced in a position where I am almost like a lever going into the clay (i.e., straight and not bent).

4. How is my body positioned vis-a-vis the wheel head?? Am I off too much to the left in my chair or too much to the right??

5. Is my bat really sitting on the wheel pins or is it sitting on the crud of yesterday's throwing??

6. At my age, I now remove my glasses when throwing to see that I am centered. If I didn't, for sure the pile of clay would be off.

7. If I find I am not able to center it I say to myself "hold your hands on either side of the ball of clay and eventually it will right itself."

8. Before starting to center did you hit the clay into a general central position on the wheel head?? This can really start a piece off well as you don't have to fight too much with it to get it to the place you want it to be from the onset.

10. What is my mood?? I find if I am anxious in anyway, it can come out in fighting with the clay.

11. What grip have I used in entering the clay? I like two fingers clasped together and pressing down with my arms braced against my body.

12. Where are my hips as they relate to the wheel head?? Are they slightly above so I am approaching the clay in a top down manner if sitting.

I could go on and on with all my neurotic thinking that I review in centering clay. I must say though, this list has helped me. I am sure there are many different aspects of this process I have forgotten?

If ever a piece that I throw is off and I cannot detect it when I am throwing and it is caught in the trimming process, I simply make the base into a triangular foot. I can cover up a lot of issues with this style of foot ring.

Just my thoughts. Please, anyone, feel free to correct me on any of these points.

Nelly


Dear All,

Just one more thing I forgot on my last post.

13. Did I cone up and then down and then up and then down and maybe a third time?

Nelly


When I have trouble centering I usually do one thing only, close my eyes! Over the year I have found that if I am paying too much visual attention to centering, it isn't going to happen.

Simply retired teacher, not dead, living the dream. on and on and. . . . on. . . .                                                                                 http://picworkspottery.blogspot.com/


#9 Clay Pigeon Pottery

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Posted 29 March 2013 - 06:13 PM

I find that I can pull a perfectly-centered lump of clay off-center when I open with too much pressure or speed.



#10 Kohaku

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Posted 29 March 2013 - 06:18 PM

Dear All,

When I have trouble either centering a piece of seeing that it goes off during throwing I go through a bunch of thought processes... (please feel free to correct me in anyway if I am wrong).

1. Is my wheel level (i.e., has my wheel shifted and is it as close to level as possible using the guage). I use shims or elevate the legs if required to make it level.

2. Have I wedged my clay properly?? Are there lumps or places of air knocking it off??

3. Am I braced in a position where I am almost like a lever going into the clay (i.e., straight and not bent).

4. How is my body positioned vis-a-vis the wheel head?? Am I off too much to the left in my chair or too much to the right??

5. Is my bat really sitting on the wheel pins or is it sitting on the crud of yesterday's throwing??

6. At my age, I now remove my glasses when throwing to see that I am centered. If I didn't, for sure the pile of clay would be off.

7. If I find I am not able to center it I say to myself "hold your hands on either side of the ball of clay and eventually it will right itself."

8. Before starting to center did you hit the clay into a general central position on the wheel head?? This can really start a piece off well as you don't have to fight too much with it to get it to the place you want it to be from the onset.

10. What is my mood?? I find if I am anxious in anyway, it can come out in fighting with the clay.

11. What grip have I used in entering the clay? I like two fingers clasped together and pressing down with my arms braced against my body.

12. Where are my hips as they relate to the wheel head?? Are they slightly above so I am approaching the clay in a top down manner if sitting.

I could go on and on with all my neurotic thinking that I review in centering clay. I must say though, this list has helped me. I am sure there are many different aspects of this process I have forgotten?

If ever a piece that I throw is off and I cannot detect it when I am throwing and it is caught in the trimming process, I simply make the base into a triangular foot. I can cover up a lot of issues with this style of foot ring.

Just my thoughts. Please, anyone, feel free to correct me on any of these points.

Nelly


This is a great list.

Just yesterday, I was throwing off a bat, and had four pieces in a row fail due to centering issues. After banging my head, it occurred to me to check under the bat. There was about a one-milimeter piece of grog lodged down between the bat and the wheelhead.

Little things matter.
Not all who wander are lost

#11 StokedAboutWoodFiring

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Posted 29 March 2013 - 11:32 PM

Yea, I'd say check for any issues with the bats either slipping while throwing or being uneven from the get go.

When opening, I always imagine my inner (left) hand (or thumbs/fingers) applying 3/4 of the pressure, and then place the palm of my right hand on the outside to apply the last 1/4 of the pressure. The outter hand is simply in charge of holding the piece on center, and it is weighted on my thigh or hip so it is as strong/stable as can be. The only thing actually moving clay is my fingers on the inside. Like others said, go slower than you think necessary- make sure your finger tips are wet and you have your hand/arm in the most stable position possible. The motion of the wheel alone always keeps a piece on center, so you know that if your body motion is centered/slow and applies equal and constant pressure then your piece will remain perfectly centered throughout the throwing process. Those should be the only two factors that interfere with the forming of whatever clay you have on the wheel.

In terms of making sure you have the clay centered before you open, I always shut my eyes and hold the "centered" mound lightly in my hands as the wheel spins at medium speed. I do this after I am visually satisfied with the shape of the mound, and when I truly think it's entirely on center. You'll be surprised how much easier it is to identify a wobble with your eyes closed!

Best of luck!
Ryan

#12 OffCenter

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Posted 30 March 2013 - 08:05 AM

Just yesterday, I was throwing off a bat, and had four pieces in a row fail due to centering issues. After banging my head, it occurred to me to check under the bat. There was about a one-milimeter piece of grog lodged down between the bat and the wheelhead.

Little things matter.


Sounds like the princes and the pea. I can't imagine that interfering with centering unless it was causing the bat to wobble.

Jim
E pur si muove.

"But it does move," said Galileo under his breath.

#13 Pres

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Posted 30 March 2013 - 10:30 AM


Just yesterday, I was throwing off a bat, and had four pieces in a row fail due to centering issues. After banging my head, it occurred to me to check under the bat. There was about a one-milimeter piece of grog lodged down between the bat and the wheelhead.

Little things matter.


Sounds like the princes and the pea. I can't imagine that interfering with centering unless it was causing the bat to wobble.

Jim


One of the reasons I use a bat pad under all of my bats. The dampened pad seems to really help.

Simply retired teacher, not dead, living the dream. on and on and. . . . on. . . .                                                                                 http://picworkspottery.blogspot.com/


#14 Benzine

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Posted 30 March 2013 - 05:34 PM


Here's a way.....

http://www.dickblick...kcenter-system/

......Waits for OffCenter.....



The only thing worse than a splash pan is a Griffin Grip and the only thing worse than a Griffin Grip is this piece of crap!

Jim


Well, at least you loath this worse than the Giffin Grip. I can understand why you think the quick center system is absurd, and even why you don't like the Grip, but splash pans? I know quite a few potters don't use them, because they throw, relatively dry, but to say they are almost as bad as the aforementioned items? I can understand, if you didn't like a certain type of pan, like those that are built in, but all of them.
"Anything worth believing, is worth questioning"

#15 OffCenter

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Posted 30 March 2013 - 06:05 PM



Here's a way.....

http://www.dickblick...kcenter-system/

......Waits for OffCenter.....



The only thing worse than a splash pan is a Griffin Grip and the only thing worse than a Griffin Grip is this piece of crap!

Jim


Well, at least you loath this worse than the Giffin Grip. I can understand why you think the quick center system is absurd, and even why you don't like the Grip, but splash pans? I know quite a few potters don't use them, because they throw, relatively dry, but to say they are almost as bad as the aforementioned items? I can understand, if you didn't like a certain type of pan, like those that are built in, but all of them.


For me splash pans are just something in the way and something hard to clean. A sponge between the wheelhead and water bowl keeps you almost as clean as a splash pan and doesn't get in the way when you're throwing a big bowl and trying to get up under the bowl and can be moved out of the way and cleans up with a squeeze. Plus, unlike Griffin Grips and that silly centering thing, most wheels come with them, meaning you have to pay for them even if you toss the splash pan as soon as you get the wheel.

Jim
E pur si muove.

"But it does move," said Galileo under his breath.

#16 OffCenter

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Posted 30 March 2013 - 06:09 PM

The best wheel available, Soldner, doesn't come with a splash pan.

Jim
E pur si muove.

"But it does move," said Galileo under his breath.

#17 Surubee

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Posted 30 March 2013 - 08:31 PM

If you are having trouble when you are opening and you think your clay was reasonably centered when you started, it may be that you are throwing it off center when you open it. I often see students letting go of the clay abruptly when they open. Often this will knock it off center, then it becomes increasingly difficult to recenter and throw. When you open, (no matter what method you use for that), make sure the clay is wet enough not to stick to your fingers, then once you have created the initial hole in the middle of the ball of clay - using enough pressure for that - try to relax your hands before you let go so that you release the clay gently, not suddenly.

Best of luck to you!

Susan

#18 Benzine

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Posted 31 March 2013 - 08:30 AM




Here's a way.....

http://www.dickblick...kcenter-system/

......Waits for OffCenter.....



The only thing worse than a splash pan is a Griffin Grip and the only thing worse than a Griffin Grip is this piece of crap!

Jim


Well, at least you loath this worse than the Giffin Grip. I can understand why you think the quick center system is absurd, and even why you don't like the Grip, but splash pans? I know quite a few potters don't use them, because they throw, relatively dry, but to say they are almost as bad as the aforementioned items? I can understand, if you didn't like a certain type of pan, like those that are built in, but all of them.


For me splash pans are just something in the way and something hard to clean. A sponge between the wheelhead and water bowl keeps you almost as clean as a splash pan and doesn't get in the way when you're throwing a big bowl and trying to get up under the bowl and can be moved out of the way and cleans up with a squeeze. Plus, unlike Griffin Grips and that silly centering thing, most wheels come with them, meaning you have to pay for them even if you toss the splash pan as soon as you get the wheel.

Jim


To each their own. I like using my splash pans. I will agree, they do get in the way, for larger forms, but that's not something I do regularly, at this point.

The best wheel available, Soldner, doesn't come with a splash pan.

Jim


No worries there, I can't afford the best type of wheel..........or the second best, or probably even the third....
"Anything worth believing, is worth questioning"

#19 yedrow

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Posted 31 March 2013 - 11:24 PM

For me, close to center is close enough. If you can neither feel a wobble nor see a wobble then it's close enough. The only real value of centering lie in its effect on where and how you put the opening hole. You want that hole to be as close to exactly center as you can get it. I do this by creating a dent in the top, letting my right thumb ride on the interior of the rim of that dent, then using it to guide my left thumb to the depth of my hole.

Like everything else in wheel thrown pottery it is best to use a smooth motion that moves at the same speed through the length of that motion. If you do this right they hole should make itself.

After that you need to make sure your opening fingers travel away from the center at an even distance from the bat. This allows the bottom to be even, and more importantly in this case, it keeps spirals from forming in the bottom. The excess clay in those uneven spirals comes from the walls of the pot which is now back to uneven. Uneven feels the same as uncentered.

Joel.

#20 OffCenter

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Posted 01 April 2013 - 08:40 AM

Centering is overrated. Once you get centering down so that it is so easy that it's automatic and you don't even have to try, then you should deliberately avoid perfect centering. The perfectly centered pot isn't worth throwing.

OffCenter
E pur si muove.

"But it does move," said Galileo under his breath.




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