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slab roller vs. extruder vs. press

updated thu 16 nov 00

 

jack@pacifier.com on sun 12 nov 00


I have been making tiles for about 4-5 years and have exclusively used a
slab roller to produce my tile blanks. This method has proven to be
somewhat satisfactory however, as expected, I do have a fair amount of
warping. I am wondering if I would have a better percentage of flat tiles
if I change to using an extruder or tile press as opposed to the slab
roller. Does anyone have any experience in this area? I have searched the
Clay Art archives, but can not find much that addresses this issue.

As additional information, I am producing 3", 4 1/3" and 6" tiles. I use
cone 6 stoneware clay with grog. I use proper handling and drying
techniques.

Any comments and/or advice would be appreciated.

Thanks in advance for your help,

Jack

mudlark on sun 12 nov 00


There a number of reasons for warping. The glaze can cause them to cup up - too
thin. Bending them in the process - don't bend them they remember it. I've seen
it where they are dried between pieces of sheet rock and that can work.

"jack@pacifier.com" wrote:

> I have been making tiles for about 4-5 years and have exclusively used a
> slab roller to produce my tile blanks. This method has proven to be
> somewhat satisfactory however, as expected, I do have a fair amount of
> warping. I am wondering if I would have a better percentage of flat tiles
> if I change to using an extruder or tile press as opposed to the slab
> roller. Does anyone have any experience in this area? I have searched the
> Clay Art archives, but can not find much that addresses this issue.
>
> As additional information, I am producing 3", 4 1/3" and 6" tiles. I use
> cone 6 stoneware clay with grog. I use proper handling and drying
> techniques.
>
> Any comments and/or advice would be appreciated.
>
> Thanks in advance for your help,
>
> Jack
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.

Paul Lewing on sun 12 nov 00


HI, Jack,
I've made tiles by all the methods you've described, and there are
problems with each.
The problem of keeping tiles flat that you've made on the slab roller
has been discussed at length here, so I won't go into that. There's
plenty in the archives.
But as to extruding them, my experience is that they stay flatter, but
they tend to not be as straight on the edges. Keep in mind that I'm
making them on a studio size extruder, not one of those pugmill
extruder. I think those make much better, flatter, straighter tile than
the studio size ones do.
I also have pressed them, and I think it does keep them flatter. It
seems to relieve the plastic memory in them. However, most people who
press tiles are doing so because they want a tile that is not flat all
over, and the differences in thickess across the tile can cause warping
in itself. Also, if you make tiles with raised decoration on them, you
may not be able to use that technique of stacking them up with layers of
sheet rock, which is so good at keeping flat tiles flat. Of course, if
all you're pressing is incised lines, I don't think that's much
different than just pressing a flat tile, in terms of warpage. Another
danger in pressing tiles is that it's easy to warp them as you peel them
off the mold. You need some patience here. If you leave them on the
mold for a while, they pop off easier. It helps in terms of efficiency
if you have a bunch of molds that you're pressing at once. Then you
press them all, and don't take them off till all your molds are full.
I hope this helps.
Paul Lewing, Seattle

jack@pacifier.com on wed 15 nov 00


Hi Paul.....

Thanks for responding to my posting on ClayArt regarding equipment for
making tiles. I'm interested in trying other equipment in an effort to
obtain a higher percentage of flat tiles, but didn't want to spring the
bucks for it until I had a chance to find out if it really would help any.

I've probably read most all of the postings regarding flat tiles and slab
rollers and have been using most of the techniques. I suppose part of my
problem could be that I'm too picky about how much warp is acceptable and I
end up throwing away 10 - 20% of 3" and 4 1/4" tiles and about 70 - 80% of
6" and larger. I've also been on a clay hunt figuring that maybe the clay
bodies I have been using don't measure up (I've been using Pioneer White
w/grog and a variety of reds that I have been buying from Georgie's in
Portland). Recently I took a run up to Seattle and Tacoma (I live in
Vancouver, WA) and picked up some Oregon Red and SMY from Clay Art Center
and Klamath Brown and Morgan from Seattle Pottery to try out in an effort
to find a better clay body. I'll keep my fingers crossed.

Thanks again for your assistance.

Best Regards,

Jack

-----Original Message-----
From: Paul Lewing [SMTP:pjlewing@WORLDNET.ATT.NET]
Sent: Sunday, November 12, 2000 8:47 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Slab Roller vs. Extruder vs. Press

HI, Jack,
I've made tiles by all the methods you've described, and there are
problems with each.
The problem of keeping tiles flat that you've made on the slab roller
has been discussed at length here, so I won't go into that. There's
plenty in the archives.
But as to extruding them, my experience is that they stay flatter, but
they tend to not be as straight on the edges. Keep in mind that I'm
making them on a studio size extruder, not one of those pugmill
extruder. I think those make much better, flatter, straighter tile than
the studio size ones do.
I also have pressed them, and I think it does keep them flatter. It
seems to relieve the plastic memory in them. However, most people who
press tiles are doing so because they want a tile that is not flat all
over, and the differences in thickess across the tile can cause warping
in itself. Also, if you make tiles with raised decoration on them, you
may not be able to use that technique of stacking them up with layers of
sheet rock, which is so good at keeping flat tiles flat. Of course, if
all you're pressing is incised lines, I don't think that's much
different than just pressing a flat tile, in terms of warpage. Another
danger in pressing tiles is that it's easy to warp them as you peel them
off the mold. You need some patience here. If you leave them on the
mold for a while, they pop off easier. It helps in terms of efficiency
if you have a bunch of molds that you're pressing at once. Then you
press them all, and don't take them off till all your molds are full.
I hope this helps.
Paul Lewing, Seattle

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You may look at the archives for the list or change your subscription
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Moderator of the list is Mel Jacobson who may be reached at
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