JanetH13@aol.com on mon 7 apr 97
I'm submitting this request for help to Clayart on behalf of Kim, a friend in
my ceramics class. She has spent a semester and a half working on a very
ambitious project, a coffee table which will be inlaid with tiles.
The tiles are approximately 7" X 7", 1/4" thick stoneware fired to cone 9 in
reduction. I believe there are 12 tiles altogether. They are intricately
carved and stamped, and when laid out form a landscape with buildings with
lots of architectural detail. They were stained with iron oxide and various
stains.
She commissioned a metal artist to make the table frame, and planned to place
plywood on top of the frame. There's a dropped seat in the metal frame to
hold the wood--the drop is 3/4". Based on advice she received from our
teacher, she planned to use 1/2 inch thick plywood, then use mastic, then
grout the 1/4 inch tiles. This would have resulted in an almost perfectly
level table top, except of course for the relief in the tile design. (The
relief is fairly shallow.)
She now has two problems:
1. The director of our art department saw the project and says that 1/2 inch
plywood will probably warp, which would then probably cause the tile and
grout to crack. He says that she should have used at least 3/4" plywood
because it is higher quality and less likely to warp. However, the table
frame was designed for the 1/2 inch width, and anything thicker will cause
the tile surface to stick up above the metal frame.
2. She wanted to seal the tiles to protect them from wet glasses, dirt and
other wear and tear. She talked to someone in a tile store, explained what
she was doing, and purchased a sealant. She wanted a colorless, matt
sealant. She did tests and then applied the sealant. After the tiles dried,
in some places there was a slight chalky film. It's not severe, but she
hates it and feels is obscures some of the detail. It's most noticeable on
areas with darker stains. She's afraid that if she tries to remove the
sealant, she'll damage the stain.
Can any of you offer suggestions as to how to correct or work around these
problems? Could she use something other than plywood as a base? Could she
cover the sealant with another type of product? Any other ideas or
suggestions?
Thanks very much for any help you can give us.
Janet
Ellen Barrosse on mon 7 apr 97
> She now has two problems:
>
> 1. The director of our art department saw the project and says that 1/2
inch
> plywood will probably warp, which would then probably cause the tile and
> grout to crack. He says that she should have used at least 3/4" plywood
> because it is higher quality and less likely to warp. However, the
table
> frame was designed for the 1/2 inch width, and anything thicker will
cause
> the tile surface to stick up above the metal frame.
>
Professional tile installers put a product called Wonderboard, essentially
a board made of concrete on top of the plywood to stabilize the tile. I
wonder whether you could use wonderboard instead of the plywood.
Carol Jackaway on mon 7 apr 97
We have two suggestions for the tile table...................the table top it
self....Use thin metal braces. If these can not be inlaid then drill small
holes into the metal frame, in lay the plywood, metal stripes accross bottom
and screw into wood through small hole
Tiles....I have used acrlyic spray to seal the surface of pit fired peices.
It seals but dosen't leave a shiney surface Just some thoughts good luck
CoilLady
LINDA BLOSSOM on mon 7 apr 97
Dear Janet,
The person who recommend 3/4 is correct. Movement is what is unacceptable
and 1/2 plywood is not usable. She could reduce the grout lines on the
interior just enough to widen the outside lines and then let the grout
lines on the perimeter rise a bit, producing a slight angle, from the
metal edge to the tiles. It would be a slight slope. The change in
elevation need not be bad. I would not use mastic however, for the
setting. Thinset is far better and will take up any unevenness in the
tiles and provide a good solid bed between the tiles and the plywood. I
gather from your post that the tiles are unglazed. Tell your friend to
check out the product Sealers Choice. It is a very expensive, small can of
sealer. It is unlike any of the acrylic or latex products. It will not
change the surface at all. It has a 10 year warranty. It is made by Aqua
Mix. I purchased an unglazed, stoneware bowl from a woman once and used
this product on it. It is waterproof and you would never know the sealer
is there. Seal before grouting or it will be a nighmare getting the grout
off.
Linda Blossom
2366 Slaterville Rd.
Ithaca, NY 14850
607-539-7912
blossom@lightlink.com
http://www.artscape.com
Bill Aycock on mon 7 apr 97
At 12:23 AM 4/7/97 EDT, you wrote:
>----------------------------Original message----------------------------
There's a dropped seat in the metal frame to
>hold the wood--the drop is 3/4". Based on advice she received from our
>teacher, she planned to use 1/2 inch thick plywood, then use mastic, then
>grout the 1/4 inch tiles.
>
>She now has two problems:
>
>1. The director of our art department saw the project and says that 1/2 inch
>plywood will probably warp, which would then probably cause the tile and
>grout to crack. He says that she should have used at least 3/4" plywood
>because it is higher quality and less likely to warp. However, the table
>frame was designed for the 1/2 inch width, and anything thicker will cause
>the tile surface to stick up above the metal frame.
>
I cant help on the sealer problem, but the problem with the 3/4 vs 1/2 in
Ply is easy- Have the 3/4 inch ply cut with a 1/4 offset groove around the
BOTTOM edge of the plank- It will then sit down in the frame, with some of
the plank below the frame. You get the stiffness of the added thickness,
without raising the top surface.
Like this:
_____________________
|
|___
|_________________
(This idea is of the type known as an "AHA", or "of course", depending on
whether you are looking from the inside or the outside.)
Bill- enjoying the WONDERFULL spring on Persimmon Hill, but contemplating
his SEVENTIETH, which occurs tomorrow.
Bill Aycock --- Persimmon Hill --- Woodville, Alabama, USA
--- (in the N.E. corner of the State)
also-- W4BSG -- Grid EM64vr baycock@hiwaay.net
Pat Wehrman on mon 7 apr 97
Have her try cement board to mount the tile on- it comes in 1/2" thickness.
It's a pain to cut, but it can be done well with a sharp blade. There is also
hardibacker, 1/4" thick. Check at a good hardware store for these materials.
For sealing, commercial tile sealers can cause the haze you spoke of. After the
sealer is applied, it's important to wipe up any excess to avoid the whitening.
Perhaps she would like to try paste wax. I've had alot of success with it, it
can be buffed, is water-resistant and makes it easy to clean.
Another option would be to mount the tile on 1/4" hardibacker, then cover with
1/4" glass with felt pads in the corners. That will save the relief from
accumulating crumbs. Just another idea....
Pat wehrman@goldrush.com
Robert Kittel on tue 8 apr 97
Thinset morter will work but must be mixed with a latex additive. Making the
bed even doesn't depend on the type of adhesive but is more dependant on the
size of the notch on the trowel. One half inch ply will work if it is of a
good quality like some of the mutilayered scandanavian plywoods. Perhaps
backing the 1/2 inch plywood with a cross brace under it and then attaching
it from underneath. Flexibilty shouldn't be a problem unless you plan on
dancing on your table.
At 04:28 PM 4/7/97 +0000, you wrote:
>----------------------------Original message----------------------------
>Dear Janet,
>
>The person who recommend 3/4 is correct. Movement is what is unacceptable
>and 1/2 plywood is not usable. She could reduce the grout lines on the
>interior just enough to widen the outside lines and then let the grout
>lines on the perimeter rise a bit, producing a slight angle, from the
>metal edge to the tiles. It would be a slight slope. The change in
>elevation need not be bad. I would not use mastic however, for the
>setting. Thinset is far better and will take up any unevenness in the
>tiles and provide a good solid bed between the tiles and the plywood. I
>gather from your post that the tiles are unglazed. Tell your friend to
>check out the product Sealers Choice. It is a very expensive, small can of
>sealer. It is unlike any of the acrylic or latex products. It will not
>change the surface at all. It has a 10 year warranty. It is made by Aqua
>Mix. I purchased an unglazed, stoneware bowl from a woman once and used
>this product on it. It is waterproof and you would never know the sealer
>is there. Seal before grouting or it will be a nighmare getting the grout
>off.
>
>Linda Blossom
>2366 Slaterville Rd.
>Ithaca, NY 14850
>607-539-7912
>blossom@lightlink.com
>http://www.artscape.com
>
Luther Norman on tue 8 apr 97
JanetH13@aol.com wrote:
>
> ----------------------------Original message----------------------------
> I'm submitting this request for help to Clayart on behalf of Kim, a friend in
> my ceramics class. She has spent a semester and a half working on a very
> ambitious project, a coffee table which will be inlaid with tiles.
>
> The tiles are approximately 7" X 7", 1/4" thick stoneware fired to cone 9 in
> reduction. I believe there are 12 tiles altogether. They are intricately
> carved and stamped, and when laid out form a landscape with buildings with
> lots of architectural detail. They were stained with iron oxide and various
> stains.
>
> She commissioned a metal artist to make the table frame, and planned to place
> plywood on top of the frame. There's a dropped seat in the metal frame to
> hold the wood--the drop is 3/4". Based on advice she received from our
> teacher, she planned to use 1/2 inch thick plywood, then use mastic, then
> grout the 1/4 inch tiles. This would have resulted in an almost perfectly
> level table top, except of course for the relief in the tile design. (The
> relief is fairly shallow.)
>
> She now has two problems:
>
> 1. The director of our art department saw the project and says that 1/2 inch
> plywood will probably warp, which would then probably cause the tile and
> grout to crack. He says that she should have used at least 3/4" plywood
> because it is higher quality and less likely to warp. However, the table
> frame was designed for the 1/2 inch width, and anything thicker will cause
> the tile surface to stick up above the metal frame.
>
If it is an open metal frame, you can glue another, smaller piece of
1/2" plywood to the original and let the smaller one drop through the
frame. 1/2" thickness is enough for the frame lip and the one inch
piece across the middle will hold the tile. Even beveling the second
piece however will allow it to show from the side. Just a thought.
-Luther
Paul Monaghan on tue 8 apr 97
>
> Janet
Hi Janet,
the real question is what are the dimensions of the table.
Paul
--
Paul J. Monaghan email: paul@web2u.com
WEB2U Productions --- http://www.web2u.com
The "COOLEST" Site on the WEB
"The Computer Secrets are hidden at www.web2u.com/secret"
Steve Hum on tue 8 apr 97
Janet,
I teach a middle school class where we make tile top tables and have always
used 3/4 inch plywood, then a layer of thin set to attach the tile, then the
grout. We have made about 450 tables so far and no problems, so I too would
have recommended the thicker plywood. I wonder if your friend could glue and
screw another layer of 1/2 inch thick plywood to the under side of the 1/2 in
piece that will sit into the originally designed frame? This way the only
part that is 1/2 inch is just a 3/4 in perimeter that drops into the frame. I
hope this make sense?
As for the sealer that she applied, I have at times had kids who wanted to
paint rather than glaze sculptures and if the results were not to successful
I just refire them and the kiln burns away the paint and they have another go
at it. As always, do a test first!
Good luck,
Steve Hum
Richard Ramirez on tue 8 apr 97
Janet,
Tell your friend, that clay is almost undestructable,even when it's crush to
powder you can start all over again. Probably the best thing to do is to
re-fire the tiles to get rid of the sealent and start over. As for the
plywood, you can try sealing that or use something synthetic, or even metal.
Your probably be all right if you went ahead and use plywood, if it did wrap
you can redo it. Besides it's important to move under your own power, see
what happens, take a few risks, learn from your actions, trust your vibs.
Hope this is some encouragement? Good Luck! Keep us posted.
R12396,Richard "The Clay Stalker"
LINDA BLOSSOM on wed 9 apr 97
Wonderboard in this situation is not an option. On a horizontal surface, it
must be used over a substrate such as plywood. It is fragile, in spite of
being made of cement. The suggestion for the metal bars may be
acceptable if you are using a hardwood plywood - usually purchased from
suppliers who sell furniture grade wood. Ask a furniture maker about this.
This plywood is less likely to warp. However, it would have to be well
attached in enough places to flatten it out and keep it that way.
Linda Blossom
2366 Slaterville Rd.
Ithaca, NY 14850
607-539-7912
blossom@lightlink.com
http://www.artscape.com
PJLewing@aol.com on wed 9 apr 97
Janet,
If your friend's table is not going outside, I would not expect a piece of
1/2" plywood to warp significantly. Especially if some cross-bracing could
be added in the middle of the table. The suggestion of Wonderboard is a good
one, as the thin-set cement that I would reccommend over Mastic for use on
that will adhere better, but it will not be as strong as plywood. There is
another tile backing product called Hardi-Backer that comes in 1/4"
thickness, too. Perhaps laminating that on top of 1/4" TEMPERED Masonite,
which is more rigid than 1/4" plywood would be a good solution, but not for
outside. I would screw and glue the 2 sheets together using a construction
adhesive like DAP 400 or Beatsnails. And if you must use plywood, use marine
plywood and varnish it if it's going outside.
I've used a fence and deck adhesive for exterior tile murals mounted on
plywood and had no trouble (yet). But Michelle Griffoul (back cover of CM)
says she's had trouble with everything but 100% silicone. If you use a
cement-board product, use thin-set cement; if you use plywood, use a
construction adhesive. Don't use Max-Bond. I am now getting 5-year-old
pieces returned that are falling apart that were glued with that.
Paul Lewing, Seattle
http://digitalfire.com/education/magic.htm
clayphil@aol.com on wed 9 apr 97
Hi Janet,
Yes, you need 3/4" ply. You might try a 1/4" rabbit joint around the bottom edg
3/4 ply should still stay stable enough to prevent damage and be the 1/2" heigh
interfere.
___________
| |_ 3/4 Ply
|--- |_______
|
|
^
Metal frame. Good Luck, Measure Twice/ Cut Once. Phi
| |
|
