Jeff Lawrence on sun 19 oct 97
June Perry writes:
>I think the big difference is time. It takes a long time, comparatively, to
>weight out a glaze batch using a triple balance beam. You have to wait for
>the beam to balance and it takes forever.
Hi June,
I think that this problem may have been solved since you got your scale. One
of my employees brought in an old Ohaus with a lovely hammered metal finish
to show me. It is much nicer looking than my newer (vintage 1985) Ohaus,
though most of the components are identical.
But mine does not have the problem you describe. It has a slow-down
mechanism where a blade attached to the beam assembly slices between magnets
on the frame, which deadens the up and down action to maybe one or two
swings. The older model dances around for minutes, it is true.
I incline to the triple beam over electric mainly because I already have too
many extension cords snaking around.
Just a little more mud for the waters,
Jeff
Jeff Lawrence
jml@sundagger.com
Sun Dagger Design
Rt 3 Box 220
Espanola, NM 87532
ph 505-753-5913
fax 505-753-8074
Akitajin \"Lee Love\" on mon 20 oct 97
Digital is always faster, unless the power goes off. ;^)
Sometimes slower is better. When I mix glazes, I use the time the
triple beam is taking to settling, to check and make sure I have the right
numbers on the scale and the right ingredience in the bucket. If the
process was sped up (like so many things in our post-post-modern world) I'd
make more mistakes. Of course, you can cheat and put a finger on the
guide & the beam will stop moving quickly, but I don't see the need to do
so. The swinging is meditative and soothing.
I am glad the people who use pottery are not totally enamored with
efficency. If they were, they'd be using paper plates and plastic
instead of pottery. ;^)
There is a sort of beauty and simplicity in a triple beam.
Lee
/(o\' Lee In Saint Paul, Minnesota USA
\o)/' mailto:Ikiru@Kami.com
' http://www.millcomm.com/~leelove/ikiru.html
June Perry on mon 20 oct 97
Dear Jeff:
Yes my triple beam is a bit ancient - about 25 years old. Glad to see the new
ones
have improved the time factor greatly. Mine takes forever to weight out each
ingredient.
My new super duper digital Ohaus arrived yesterday! Looking forward to lots
of glaze testing as soon as the studio re-organization is complete!
Warm regards,
June
David Hendley on tue 21 oct 97
With this talk about scales, I thought you all might like to hear about mine.
I agree with Lee that there is a certain beauty in a triple beam scale set.
Kinda like the beauty in a kiln arch.
Ancient,
low-tech, yet elegant.
If you prefer flat top kilns and electronic scales that's fine.
I can't imagine subjecting myself to buying more batteries or
having more extension cords when I can do just as well without them.
Another, subtle, but I think important, observation:
Digital readouts change the way you "think" about things.
Let's compare digital and analog watches.
If you asked someone the time and they had a digital watch,
their answer might be "nine-forty-six".
The person with an old fashioned watch would probably not
give that answer.
You would probably get "nine-forty-five" or "quarter to ten".
Which answer is more accurate?
Who knows? Very few watches are set to one minute accuracy
because it's unimportant. The correct time might be exactly 9:45.
What a watch dial gives you is meaningful information about
"relationships".
If you have to be somewhere at 10 you can "see" how long you
have to get there.
With a digital readout it becomes a cerebral matter, and sometimes
the implied accuracy is false.
When using a triple beam YOU decide how much accuracy you want.
When doing a 100 gram test you can carefully wait until
the pointer is exactly centered, for complete accuracy.
When doing a 10,000 gram batch, forget it.
As long as the needle is moving on the scale you are close enough.
Like the analog watch, you can actually SEE what is happening
and how accurate you are being.
Truth be told, I don't even use the "ones" beam when weighing working
batches of glaze.
If it's supposed to be a "2" I just am aware of it and aim the pointer
a little towards the high end of the scale.
Now, the story of my scales:
They were FREE.
Belonged to a paper salesman. I guess he weighed paper.
The old "hammered grey" kind, already old in 1974.
Anyway, there was a "minor" fire in his office and the scales
were covered with soot and a couple of things were slightly melted.
They cleaned up great, but would not balance out.
Three pennies under the platform, screw the platform back on, and
back in business.
Uh-oh, no "tens" weight.
Why call Ohaus for a replacment?
Fabricated a new one out of the flat bar that goes over the two ends
of a "U" bolt.
Uh-oh, again. No bowl or scoop, just a platform.
Well a plastic bowl works great.
Bigger than the too- small scoop that is standard.
How about a counterbalance for the bowl?
Have you seen, in the hardware store, the little packages of screws
that come in plastic bottles, with a snap- on cap, with a hook on the cap?
Bingo. Just fill it with the correct amount of clay and it hangs
right where it's supposed to.
I have a personal relationship with my scales.
They move and have life, just like my wood-fired kiln.
We know how to work together.
David Hendley
Maydelle, Texas
See David Hendley's Pottery Page at
http://www.sosis.com/hendley/david/
Vince Pitelka on tue 21 oct 97
I am curious about all this concern with waiting for the beam to quit
moving. Why wait at all? Do a little experiment. Ond once the pointer is
level, add a bit of material and see how much it takes to send the pointer
to the the upper extreme of its movement. You will find that it is an
extremely small amount. So as long as the pointer is floating within its
range of movement you are very close. And even if you are determined to be
as precise as possible, when the pointer is moving up and down just check to
see that its movement is equally spaced within the possible range of
movement. If so, you know that when it stops it will be on center.
- Vince
Evan Dresel on tue 21 oct 97
Generally from what I have seen you get a better range on a triple-beam up
to 2.6 kg with a precision of 0.1 g (using the add-on weights on my Ohaus).
That's a lot of bang for the buck and you can use it for tests and larger
batches. The magnetic dampers on the new triple beams do speed up the
settling of the balance but the old time chemists learned how to judge the
center point of the swing and could figure out if they were over or under
weight before it came to rest. Easier to do with a double-pan balance that
has a long pointer and lots of marks on each side so you can see how far it
swings each way. The magnetic damper also messes this up because it settles
**too fast** (but not as fast as a hot-shot chemist can judge the swing).
Anyway, those of you who want to hurry the process can probably learn the
skill -- can't be too much worse than tapping to center. Like that idea of
just watching the sway. Sounds like Lee needs to live on a boat ;-).
Oh yea, triple beams are pretty rugged although I try to baby mine. It is
after all the most important measuring device I use in the studio aside from
cones.
-- Evan in W. Richland WA USA where the geese are flying, the hunters
hunting and the horses growing shaggy.
At 08:54 AM 10-20-97 EDT, you wrote:
>----------------------------Original message----------------------------
>Digital is always faster, unless the power goes off. ;^)
>
> Sometimes slower is better. When I mix glazes, I use the time the
>triple beam is taking to settling, to check and make sure I have the right
>numbers on the scale and the right ingredience in the bucket. If the
>process was sped up (like so many things in our post-post-modern world) I'd
>make more mistakes. Of course, you can cheat and put a finger on the
>guide & the beam will stop moving quickly, but I don't see the need to do
>so. The swinging is meditative and soothing.
>
> I am glad the people who use pottery are not totally enamored with
>efficency. If they were, they'd be using paper plates and plastic
>instead of pottery. ;^)
>
> There is a sort of beauty and simplicity in a triple beam.
>
>Lee
>/(o\' Lee In Saint Paul, Minnesota USA
>\o)/' mailto:Ikiru@Kami.com
>' http://www.millcomm.com/~leelove/ikiru.html
>
>
Fred Paget on wed 22 oct 97
All this talk of having to wait for the scale to stop swinging before
reading it reminds me of how I was taught to weigh on pan type ballances
back in the dim dark days before electronic scales came along.
The scales have calibrations extending out on each side of the zero mark
and the idea is to adjust it so the swing is equal on both sides of zero
and not to wait until it stops. The equal swing way of reading is fairly
fast since you do not have to wait for the swinging to stop and is more
accurate because friction in the bearings may cause the scale to stop off
center. A cheap scale that swings a little less on each cycle is read by
allowing for the smaller swing of each cycle when you make the judgement.
More modern scales with a magnetic damper are another story.
Fred Paget---Mill Valley,CA,USA
Never try, never win!
Erikyu on wed 22 oct 97
>----------------------------Original message----------------------------
>Digital is always faster, unless the power goes off. ;^)
>
> Sometimes slower is better...
> I am glad the people who use pottery are not totally enamored with
>efficency. If they were, they'd be using paper plates and plastic
>instead of pottery. ;^)
>
> There is a sort of beauty and simplicity in a triple beam.
>
>Lee
>/(o\' Lee In Saint Paul, Minnesota USA
I use a single beam scale (actually is a scrap of wood with a couple of
tupperwear cups)
I do pots for fun so a little inprecision is part of the adventure. My
scale is a 40'' ,3/4 x 3/4 piece of wood with a cup hook on each end and a
lenght of fishing line in the middle. I hang tupperware cups on each end.
In one cup is the thing being measured, in the other cup I use large and
small bolts to represent weights. If I need 23.40 of EPK I use 23 large and
4 small bolts. Naturally 10 of the small must equal 1 large but they were
easy to find. I have a small cloth loop on one side which slides in and out
to level the empty cups.
This system has worked well enough for my current needs. Someday I will
buy a nice professional scale but for now the simplicity of this homemade
setup adds to the feeling of creation.
Eric Haggin (aka Erikyu)
Concord,CA.
east@ccnet.com
" Yakimono ya
Nendo ni Shimiiru
Kama no koe "
Jean Silverman on thu 23 oct 97
At 02:05 PM 10/19/97 EDT, you wrote:
>----------------------------Original message----------------------------
>June Perry writes:
>>You have to wait for the beam to balance and it takes forever.
>
I've been weighing out glazes on an Ohaus I inherited from another potter 20
yrs ago and it was an antique then. Who ever WAITS for the beam to balance?
A strategic finger can dampen oscillations. And after a bit of practice,
adding in those final grains of powder to bring the beam to the balance
point without going too beyond becomes second nature. The great thing about
this scale is that there's nothing to break on it!
Jean--in NH where the woods are golden this time of year
Jean Silverman
Studio Potter Network
41 Neal Mill Road
Newmarket NH 03857
June Perry on fri 24 oct 97
Dear Jean:
Nothing can break but I've been told that the groove, which I haven't located
yet, can lose its tight fit in the "V" slot. In any case I had other problems
with mine. It would balance itself and then slightly touching it would put it
way out of balance without adding or subtracting any ingredients, no draft,
etc. I just got fed up with it after twenty five years and thousands of
batches later and decided to get a digital with a 2 second readout time, no
weights to put on, take off, no beam to adjust, etc. In any case, I like my
toys. :-)
Warm regards,
June
DEBBYGrant on sat 25 oct 97
Jean Silverman's comment on the triple balance beam is right on
the mark. I've never used anything else and have never had a
problem nor does it take much time. My experience with digital
anything is that they are not as accurate and I don't trust them.
But then I am probably a dinosaur.
Debby Grant in NH
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