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cracking frames.....

updated sat 23 may 98

 

Unruly JuliE on thu 21 may 98

I am making some picture frames with A.R.T.'s #125 speckled
brownstone. My slabs are 3/8" thick, and I am getting some
cracking on the inside corners of the frames.........I am drying
between two layers of drywall, so they are drying fairly even.

any suggestions to help stop cracking????????

JuliE
In michigan, where we are getting a reprieve from our summerlike
weather......

Cindy on fri 22 may 98

Julie,

I've never done picture frames, but I can tell you that sharp edges tend to
promote cracking. Try rounding your edges and see if that helps.

Cindy Strnad
Earthen Vessels
Custer, SD
USA http://blackhills-info.com/a/cindys/menu.htm

John Hesselberth on fri 22 may 98

Julie, If your inside corners are sharp that could be the source of your
problem. Stress concentrates at sharp corners/edges. Round them and see
if it helps. Even a 1/4 inch radius would be a big help. Also round the
edges leading to the inside corners.

>----------------------------Original message----------------------------
>I am making some picture frames with A.R.T.'s #125 speckled
>brownstone. My slabs are 3/8" thick, and I am getting some
>cracking on the inside corners of the frames.........I am drying
>between two layers of drywall, so they are drying fairly even.
>
>any suggestions to help stop cracking????????
>
>JuliE
>In michigan, where we are getting a reprieve from our summerlike
>weather......


John Hesselberth
Frog Pond Pottery
Pocopson, PA 19366 USA
EMail: john@frogpondpottery.com
visit my web site at http://www.frogpondpottery.com

"Why should we be in such desperate haste to succeed and in such
desperate enterprises? If a man does not keep pace with his companions,
perhaps it is because he hears a different drummer. Let him step to the
music he hears, however measured or far away." Henry David Thoreau,
Walden, 1854

Bill Aycock on fri 22 may 98

JuliE (aside- why the capitol E?)
The problem is that the clay at the corner is drying last. It is a path for
the water from a larger volume than the other edge surfaces, and therefore
has more water to pass out to the air, and therefore is late, and the
delayed shrinkage is causing the cracks.

This may work- cut a hole the size of a quarter in two of the slabs of
drywall- put the holes below and above the corner. This will still hold the
frames flat, but will let the water near the hole get out faster, therby
changing the timing of the shrinking.

I have not done this- but I think it might help. If you try it- let me know
whether I'm full of prunes, or not. (Please)

Bill- on Persimmon Hill- where the weather man says we are in for some
bodaceous anti-drying, tonight


At 06:26 PM 5/21/98 EDT, you wrote:
>----------------------------Original message----------------------------
>I am making some picture frames with A.R.T.'s #125 speckled
>brownstone. My slabs are 3/8" thick, and I am getting some
>cracking on the inside corners of the frames.........I am drying
>between two layers of drywall, so they are drying fairly even.
>
>any suggestions to help stop cracking????????
>
>JuliE
>In michigan, where we are getting a reprieve from our summerlike
>weather......
>
>

Bill Aycock --- Persimmon Hill
Woodville, Alabama, US 35776
(in the N.E. corner of the State)
W4BSG -- Grid EM64vr
baycock@HiWAAY.net