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problem with extruded handles

updated wed 27 jul 11

 

Sumi von Dassow on fri 15 jul 11


Tig

I think you wouldn't have this problem with pulled handles, but I also
think you are probably drying the handles too much before attaching
them. You are bending them, perhaps accidentally, after they have
already dried too much to take being bent. I have the best luck,
especially on porcelain, when I pull the handle directly on the mug -
i.e. attaching moist clay to a soft leather-hard mug and pulling it.
Though the mug is drier than the handle, the handle always catches up in
moisture level without cracking or cracking off. If I must extrude a
handle I attach it fairly moist so it doesn't crack when I bend it.

Sumi
> Hey All Mudbuds,
>
> I'm coming to the Ramshead Pub with a stressing problem. (Bartender, wou=
ld you please pull me a tall one?)
>
> Explanation: I prefer to attach "D" shaped handles to my mugs, as oppose=
d to the usual "?" shape. My customers like the larger opening to get more=
fingers through, and appreciate the decorative thumb knobs I put at the up=
per curve. I use Aardvark's Coleman Porcelain clay, mainly because it work=
s well on the wheel, and makes a wonderful canvas for my glazes.
>
> For the handles, I extrude about 12" of clay strip, then shape it into an=
oval around two pieces of PVC pipe glued together. I spray the PVC with W=
D-40 to make it slippery, allowing me to slide the formed ovals off the pip=
e, onto a drying bat made from sheetrock. After allowing the clay to firm =
up a little, I cut the ovals into a "C" shape, using a guillotine cheese cu=
tter to gets the ends tapered, ready for applying to the pot. So far, so g=
ood.
>
> In the past year, I have lost roughly a third to a half of my mugs to sev=
ere cracking of the handles, usually at the upper curve. Sometimes, the ha=
ndles will crack at the curve before I can attach them. This sometimes occ=
urs before I can cut them, sometimes after I have cut them, sometimes after=
I have attached them to the mug. I have tried every method I know of to p=
revent the cracking. Dry the handles to the same leather-hardness of the m=
ugs; use different slips and spoozes to attach them; dry VERY slowly; use n=
ewspaper to wrap the PVC instead of WD-40, thinking the WD-40 pulls water f=
rom the clay making a weak spot. No joy.
>
> When drying the mugs, I have tried waxing the handles; wrapping the handl=
es in moist paper towels; wrapping each bat of six mugs in dry-cleaner plas=
tic bags; double wrap the drying bats. Everything I can think of.
>
> I am out of airspeed, altitude, and ideas all at once.
>
>
> I bring the conundrum of The Cracking Handle to the board here at the Ram=
shead. What am I doing wrong? What am I missing? Any and all suggestions=
are welcome.
>
> Thanks in advance,
>
> Tig Dupre
> in Port Orchard, WA
>
>
>
>


--
Sumi von Dassow
www.herwheel.com
sumi@herwheel.com

=3D?iso-8859-1?B?VGlnIER1cHLp?=3D on fri 15 jul 11


Hey All Mudbuds=3D2C

I'm coming to the Ramshead Pub with a stressing problem. (Bartender=3D2C w=
ou=3D
ld you please pull me a tall one?)

Explanation: I prefer to attach "D" shaped handles to my mugs=3D2C as oppo=
se=3D
d to the usual "?" shape. My customers like the larger opening to get more=
=3D
fingers through=3D2C and appreciate the decorative thumb knobs I put at th=
e =3D
upper curve. I use Aardvark's Coleman Porcelain clay=3D2C mainly because i=
t =3D
works well on the wheel=3D2C and makes a wonderful canvas for my glazes.

For the handles=3D2C I extrude about 12" of clay strip=3D2C then shape it i=
nto =3D
an oval around two pieces of PVC pipe glued together. I spray the PVC with=
=3D
WD-40 to make it slippery=3D2C allowing me to slide the formed ovals off t=
he=3D
pipe=3D2C onto a drying bat made from sheetrock. After allowing the clay =
to=3D
firm up a little=3D2C I cut the ovals into a "C" shape=3D2C using a guillo=
tine=3D
cheese cutter to gets the ends tapered=3D2C ready for applying to the pot.=
=3D
So far=3D2C so good.

In the past year=3D2C I have lost roughly a third to a half of my mugs to s=
ev=3D
ere cracking of the handles=3D2C usually at the upper curve. Sometimes=3D2=
C th=3D
e handles will crack at the curve before I can attach them. This sometimes=
=3D
occurs before I can cut them=3D2C sometimes after I have cut them=3D2C som=
etim=3D
es after I have attached them to the mug. I have tried every method I know=
=3D
of to prevent the cracking. Dry the handles to the same leather-hardness =
=3D
of the mugs=3D3B use different slips and spoozes to attach them=3D3B dry VE=
RY s=3D
lowly=3D3B use newspaper to wrap the PVC instead of WD-40=3D2C thinking the=
WD-=3D
40 pulls water from the clay making a weak spot. No joy.

When drying the mugs=3D2C I have tried waxing the handles=3D3B wrapping the=
han=3D
dles in moist paper towels=3D3B wrapping each bat of six mugs in dry-cleane=
r =3D
plastic bags=3D3B double wrap the drying bats. Everything I can think of.

I am out of airspeed=3D2C altitude=3D2C and ideas all at once.


I bring the conundrum of The Cracking Handle to the board here at the Ramsh=
=3D
ead. What am I doing wrong? What am I missing? Any and all suggestions a=
=3D
re welcome.

Thanks in advance=3D2C

Tig Dupre
in Port Orchard=3D2C WA

=3D

Ron Roy on sat 16 jul 11


Hi Tig,

Sounds like a clay problem to me - it's always a good idea to use old =3D20
clay for making handles - it's usually more plastic than fresh and can =3D2=
0
take bending better.

If that clay is deflocculated - as some porcelains are - then =3D20
flocculating the clay a bit before extruding will help.

Maybe spraying the coils with vinegar after extruding and letting them =3D2=
0
rest for an hour will help.

If you want to try adding some epsom salts to a small amount of clay =3D20
to see if that will work - let me know and I'll work it out for you.

RR


Quoting Tig Dupr=3DE9 :

> Hey All Mudbuds,
>
> I'm coming to the Ramshead Pub with a stressing problem. =3D20
> (Bartender, would you please pull me a tall one?)
>
> Explanation: I prefer to attach "D" shaped handles to my mugs, as =3D20
> opposed to the usual "?" shape. My customers like the larger =3D20
> opening to get more fingers through, and appreciate the decorative =3D20
> thumb knobs I put at the upper curve. I use Aardvark's Coleman =3D20
> Porcelain clay, mainly because it works well on the wheel, and makes =3D2=
0
> a wonderful canvas for my glazes.
>
> For the handles, I extrude about 12" of clay strip, then shape it =3D20
> into an oval around two pieces of PVC pipe glued together. I spray =3D20
> the PVC with WD-40 to make it slippery, allowing me to slide the =3D20
> formed ovals off the pipe, onto a drying bat made from sheetrock. =3D20
> After allowing the clay to firm up a little, I cut the ovals into a =3D20
> "C" shape, using a guillotine cheese cutter to gets the ends =3D20
> tapered, ready for applying to the pot. So far, so good.
>
> In the past year, I have lost roughly a third to a half of my mugs =3D20
> to severe cracking of the handles, usually at the upper curve. =3D20
> Sometimes, the handles will crack at the curve before I can attach =3D20
> them. This sometimes occurs before I can cut them, sometimes after =3D20
> I have cut them, sometimes after I have attached them to the mug. I =3D2=
0
> have tried every method I know of to prevent the cracking. Dry the =3D20
> handles to the same leather-hardness of the mugs; use different =3D20
> slips and spoozes to attach them; dry VERY slowly; use newspaper to =3D20
> wrap the PVC instead of WD-40, thinking the WD-40 pulls water from =3D20
> the clay making a weak spot. No joy.
>
> When drying the mugs, I have tried waxing the handles; wrapping the =3D20
> handles in moist paper towels; wrapping each bat of six mugs in =3D20
> dry-cleaner plastic bags; double wrap the drying bats. Everything I =3D2=
0
> can think of.
>
> I am out of airspeed, altitude, and ideas all at once.
>
>
> I bring the conundrum of The Cracking Handle to the board here at =3D20
> the Ramshead. What am I doing wrong? What am I missing? Any and =3D20
> all suggestions are welcome.
>
> Thanks in advance,
>
> Tig Dupre
> in Port Orchard, WA
>
>

douglas fur on sun 24 jul 11


I think Sumi's on to it here. Pulling tends to make a skin of clay particle=
s
aligned with the legth of the handle. In extruding the drag at the surface
from he die tends to slow down the clay while the clay in tte middle goes a
little faster this tends to set up cracks in the surface. Maybe wwping down
the surfaces after extruding would heal the surface.
Why extruding? to get "D" handles I grab a wad of clay rock it back and
forth to get an ovoid section. Pat the ends to flare them out and stick em
on the pot.
DRB
Seola Creek



On Fri, Jul 15, 2011 at 8:36 PM, Sumi von Dassow wrote:

> Tig
>
> I think you wouldn't have this problem with pulled handles, but I also
> think you are probably drying the handles too much before attaching
> them. You are bending them, perhaps accidentally, after they have
> already dried too much to take being bent. I have the best luck,
> especially on porcelain, when I pull the handle directly on the mug -
> i.e. attaching moist clay to a soft leather-hard mug and pulling it.
> Though the mug is drier than the handle, the handle always catches up in
> moisture level without cracking or cracking off. If I must extrude a
> handle I attach it fairly moist so it doesn't crack when I bend it.
>
> Sumi
>
>> Hey All Mudbuds,
>>
>> I'm coming to the Ramshead Pub with a stressing problem. (Bartender,
>> would you please pull me a tall one?)
>>
>> Explanation: I prefer to attach "D" shaped handles to my mugs, as oppos=
ed
>> to the usual "?" shape. My customers like the larger opening to get mor=
e
>> fingers through, and appreciate the decorative thumb knobs I put at the
>> upper curve. I use Aardvark's Coleman Porcelain clay, mainly because it
>> works well on the wheel, and makes a wonderful canvas for my glazes.
>>
>> For the handles, I extrude about 12" of clay strip, then shape it into a=
n
>> oval around two pieces of PVC pipe glued together. I spray the PVC with
>> WD-40 to make it slippery, allowing me to slide the formed ovals off the
>> pipe, onto a drying bat made from sheetrock. After allowing the clay to
>> firm up a little, I cut the ovals into a "C" shape, using a guillotine
>> cheese cutter to gets the ends tapered, ready for applying to the pot. =
So
>> far, so good.
>>
>> In the past year, I have lost roughly a third to a half of my mugs to
>> severe cracking of the handles, usually at the upper curve. Sometimes, =
the
>> handles will crack at the curve before I can attach them. This sometime=
s
>> occurs before I can cut them, sometimes after I have cut them, sometimes
>> after I have attached them to the mug. I have tried every method I know=
of
>> to prevent the cracking. Dry the handles to the same leather-hardness o=
f
>> the mugs; use different slips and spoozes to attach them; dry VERY slowl=
y;
>> use newspaper to wrap the PVC instead of WD-40, thinking the WD-40 pulls
>> water from the clay making a weak spot. No joy.
>>
>> When drying the mugs, I have tried waxing the handles; wrapping the
>> handles in moist paper towels; wrapping each bat of six mugs in dry-clea=
ner
>> plastic bags; double wrap the drying bats. Everything I can think of.
>>
>> I am out of airspeed, altitude, and ideas all at once.
>>
>>
>> I bring the conundrum of The Cracking Handle to the board here at the
>> Ramshead. What am I doing wrong? What am I missing? Any and all
>> suggestions are welcome.
>>
>> Thanks in advance,
>>
>> Tig Dupre
>> in Port Orchard, WA
>>
>>
>>
>>
>>
>
> --
> Sumi von Dassow
> www.herwheel.com
> sumi@herwheel.com
>

Steve Mills on tue 26 jul 11


I think DF & Sumi are spot-on We often brush a little Vinegar over extrude=
d=3D
handles after attaching them, which seems to sort that problem out, but di=
d=3D
n't make the surface drag connection. Makes sense!

Steve M


Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my Ipod touch

On 24 Jul 2011, at 21:31, douglas fur <23drb50@GMAIL.COM> wrote:

> I think Sumi's on to it here. Pulling tends to make a skin of clay partic=
l=3D
es
> aligned with the legth of the handle. In extruding the drag at the surfa=
c=3D
e
> from he die tends to slow down the clay while the clay in tte middle goes=
a=3D
little faster=3D20
>=3D20
>=3D20
>=3D20
>=3D20