I currently am working on a few cherry bowls. I know that cherry will
darken upon exposure to sunlight from a maple type color to a darker reddish
color. I know this is primarily from exposure to UV light. I finish my
bowls with a few coats of Formby's Tung Oil Finish and then after thorough
drying, I use my Beall system to polish and wax. Does anyone know of
procedures to use to accelerate the rate of darkening. What might be a good
UV source that could be used close to the wood to darken it. I have a
halogen work light but I don't know the primary wavelengths of emission for
those bulbs.

Bob

In article ,
"Bob Daun" wrote:

I currently am working on a few cherry bowls. I know that cherry will
darken upon exposure to sunlight from a maple type color to a darker reddish
color. I know this is primarily from exposure to UV light.

Well, there's that big light in the sky outside - cheap, too. Put them
out in the sun for a while.

Halogen won't do much for you. And most lights that would do much are
shielded to reduce shortwave UV so they won't hurt people. Skin cancer
and itchy eyes both hurt.

You could get a germicidal UV lamp (florescent, usually - seen in things
like water filters and cabinets to store safety glasses). Some metal
halide or mercury vapor lamps sold in the aquarium trade lack the usual
UV shield layer since some UV is good for mimicking sunlight.

A good old fashioned carbon arc light is a wonderful UV source, but not
one that's all that easy to find these days. If you happen to have an
arc welder and a twin carbon arc torch, that would be the ticket to
rapid results - but wear your helmet and leathers, and don't catch the
wood on fire.

I suppose tanning lamps would likewise work, and you could get a lot of
bowls on a tanning bed if you found a tanning store going out of
business.

With any of the lights, you should arrange the lights and bowl to be in
a box or cabinet that keeps the light off your skin and eyes, and use
safety glasses and gloves/long sleeves if you are rearranging bowls with
the lights on. A better box/cabinet design would have a switch that
turned them off if the door was unlatched, and shiny reflective insides
so you got maximum use from the light.

--
Cats, coffee, chocolate...vices to live by

"Ecnerwal" wrote: (clip) A good old fashioned carbon arc light is a
wonderful UV source, but not
one that's all that easy to find these days. If you happen to have an
arc welder and a twin carbon arc torch, that would be the ticket to
rapid results - but wear your helmet and leathers, and don't catch the
wood on fire. (clip)
^^^^^^^^^^^^^^^^^^^^
They used to use carbon arc lights for burning plates in the printing
industry--they have been phased out because of the toxic fumes they produce.
I think it is hard to get the copper-coated carbon rods they use. When they
were used, they were never run more than a few minutes at a time, which I
think would be insufficient for your purposes.

Also. if you intend to use any kind of light source, you have the question
of how to get even exposure all around the bowl. You would have to rotate
it on a spit, or devise a reflective surround for the light and the bowl.

It just don't strike me as very practical.

I think the suggestion to use sunlight makes the most sense.

In article , "Bob Daun" wrote:
I currently am working on a few cherry bowls. I know that cherry will
darken upon exposure to sunlight from a maple type color to a darker reddish
color. I know this is primarily from exposure to UV light. I finish my
bowls with a few coats of Formby's Tung Oil Finish and then after thorough
drying, I use my Beall system to polish and wax. Does anyone know of
procedures to use to accelerate the rate of darkening. What might be a good
UV source that could be used close to the wood to darken it. I have a
halogen work light but I don't know the primary wavelengths of emission for
those bulbs.

There are a couple of chemical treatments you can choose from, prior to
applying finish: ammonia fuming, or lye. A solution of 1 teaspoon of lye in a
pint of water will darken cherry quite satisfactorily. Make sure to wipe it
down with diluted vinegar, and again with water, before finishing.

acid activates purple heart and makes it a very vivid color - might be worth
a try

"Bob Daun" wrote in message
...
I currently am working on a few cherry bowls. I know that cherry will
darken upon exposure to sunlight from a maple type color to a darker
reddish color. I know this is primarily from exposure to UV light. I
finish my bowls with a few coats of Formby's Tung Oil Finish and then
after thorough drying, I use my Beall system to polish and wax. Does
anyone know of procedures to use to accelerate the rate of darkening.
What might be a good UV source that could be used close to the wood to
darken it. I have a halogen work light but I don't know the primary
wavelengths of emission for those bulbs.

Bob

In article , "Bill Noble" wrote:
acid activates purple heart and makes it a very vivid color - might be worth
a try

Not on cherry. Use alkali instead -- even a weak lye solution makes cherry
quite dark. Ammonia will darken it also. I haven't tried washing soda yet to
see if it has a similar effect, but I imagine it will.

"Bob Daun" wrote in message
t...
I currently am working on a few cherry bowls. I know that cherry will
darken upon exposure to sunlight from a maple type color to a darker
reddish color. I know this is primarily from exposure to UV light. I
finish my bowls with a few coats of Formby's Tung Oil Finish and then
after thorough drying, I use my Beall system to polish and wax. Does
anyone know of procedures to use to accelerate the rate of darkening.
What might be a good UV source that could be used close to the wood to
darken it. I have a halogen work light but I don't know the primary
wavelengths of emission for those bulbs.

Bob

"Bill Noble" wrote in message
...
acid activates purple heart and makes it a very vivid color - might be
worth a try

Vivid purple turned brown when turning and sanding a pen..... what kind of
acid are you using to bring back the pruple?

"Leon" wrote: Vivid purple turned brown when turning and sanding a
pen..... what kind of
acid are you using to bring back the pruple?
^^^^^^^^^^^^^^^^^^^^^^^
Purple heart is brown when it's cut or turned, but the color returns to the
surface on exposure to air. Exposure of the purple surface to sunlight will
turn it to an ugly brown. So, after turning a pen, just wait, and don't
leave it in the window.

In article , "Leo Lichtman" wrote:

"Leon" wrote: Vivid purple turned brown when turning and sanding a
pen..... what kind of
acid are you using to bring back the pruple?
^^^^^^^^^^^^^^^^^^^^^^^
Purple heart is brown when it's cut or turned, but the color returns to the
surface on exposure to air. Exposure of the purple surface to sunlight will
turn it to an ugly brown. So, after turning a pen, just wait, and don't
leave it in the window.

Not in my experience -- I've observed the purple to be *intensified* by
sunlight.

"Doug Miller" wrote in message
...
In article , "Leo Lichtman"
wrote:

"Leon" wrote: Vivid purple turned brown when turning and sanding a
pen..... what kind of
acid are you using to bring back the pruple?
^^^^^^^^^^^^^^^^^^^^^^^
Purple heart is brown when it's cut or turned, but the color returns to
the
surface on exposure to air. Exposure of the purple surface to sunlight
will
turn it to an ugly brown. So, after turning a pen, just wait, and don't
leave it in the window.

Not in my experience -- I've observed the purple to be *intensified* by
sunlight.


I have heard it both way over the years.... From what I understand it is
loke people and will react differently to being handled differently. I have
had it go extreme purple when cutting.

In article ,
(Doug Miller) wrote:

In article , "Leo Lichtman"
wrote:

"Leon" wrote: Vivid purple turned brown when turning and sanding a
pen..... what kind of
acid are you using to bring back the pruple?
^^^^^^^^^^^^^^^^^^^^^^^
Purple heart is brown when it's cut or turned, but the color returns to the
surface on exposure to air. Exposure of the purple surface to sunlight will
turn it to an ugly brown. So, after turning a pen, just wait, and don't
leave it in the window.

Not in my experience -- I've observed the purple to be *intensified* by
sunlight.

I've had PH bleach out brown (certainly seemed to be sun-exposure
related, though filtered through two sheets of glass and a coat of
finish), but I wouldn't call it an ugly brown - more like brittle,
tool-dulling black walnut - ie, pretty good looking, but not as nice to
work with as walnut. It's mostly "not purple" rather than "ugly", IMHO.
YHO may vary, or not be H. Last I looked the bag of shavings I tucked
away in the shed was still nice and purple.

--
Cats, coffee, chocolate...vices to live by

"Leo Lichtman" wrote in message
...

"Leon" wrote: Vivid purple turned brown when turning and sanding a
pen..... what kind of
acid are you using to bring back the pruple?
^^^^^^^^^^^^^^^^^^^^^^^
Purple heart is brown when it's cut or turned, but the color returns to
the surface on exposure to air. Exposure of the purple surface to
sunlight will turn it to an ugly brown.

I don't buy it.. LOL... This pen is 1 year old now and some 10 year old
purple heart candle holders I made still have the same brown spots.

"Leon" wrote in message
...

"Bill Noble" wrote in message
...
acid activates purple heart and makes it a very vivid color - might be
worth a try

Vivid purple turned brown when turning and sanding a pen..... what kind of
acid are you using to bring back the pruple?

HCL

"Bill Noble" wrote in message
...


"Leon" wrote in message
...

"Bill Noble" wrote in message
...
acid activates purple heart and makes it a very vivid color - might be
worth a try

Vivid purple turned brown when turning and sanding a pen..... what kind
of acid are you using to bring back the pruple?

HCL


Hydracloric?

In article , "Leon" wrote:

"Bill Noble" wrote in message
...


"Leon" wrote in message
...

"Bill Noble" wrote in message
...
acid activates purple heart and makes it a very vivid color - might be
worth a try

Vivid purple turned brown when turning and sanding a pen..... what kind
of acid are you using to bring back the pruple?

HCL


Hydracloric?

Right pronunciation, wrong spelling: hydrochloric (hydro[gen] + chlor[ine]).
Any swimming-pool supply shop will have it, but it may be pretty pricy. It's
also available in many hardware stores under the name "muriatic acid" -- same
stuff, but usually much cheaper than at a pool shop.

I am very inexperienced at this, but I have made 5 cherry bowls. I
spend more time sanding them than anybody else does, probably. As I am
sanding/polishing them them with pretty fine grits, let's say 600 or so,
the heat from the sanding darkens them a fair amount. I even tried
polishing a couple with the back side of the sandpaper, and I can see
definite darkening from that. So far, I have only been finishing them
with a can of natural ancient linseed oil and that darkens them even
more. This is all air dried for 5 or 6 years, cherry that I cut myself.

Pete Stanaitis
---------------------

Bob Daun wrote:

I currently am working on a few cherry bowls. I know that cherry will
darken upon exposure to sunlight from a maple type color to a darker
reddish color. I know this is primarily from exposure to UV light. I
finish my bowls with a few coats of Formby's Tung Oil Finish and then
after thorough drying, I use my Beall system to polish and wax. Does
anyone know of procedures to use to accelerate the rate of darkening.
What might be a good UV source that could be used close to the wood to
darken it. I have a halogen work light but I don't know the primary
wavelengths of emission for those bulbs.

Bob

In article , spaco wrote:
I am very inexperienced at this, but I have made 5 cherry bowls. I
spend more time sanding them than anybody else does, probably. As I am
sanding/polishing them them with pretty fine grits, let's say 600 or so,
the heat from the sanding darkens them a fair amount.

That's called "burning". It's entirely different from the rich red-brown
patina that cherry acquires after a few years of exposure to sunlight.

We bought a Cherry Grandfather clock in 87 and it glows very nice.
Sadly spiders got into it and jammed the gears. Put camphor balls to run off
people and spiders. :-)

Martin

Doug Miller wrote:
In article , spaco wrote:
I am very inexperienced at this, but I have made 5 cherry bowls. I
spend more time sanding them than anybody else does, probably. As I am
sanding/polishing them them with pretty fine grits, let's say 600 or so,
the heat from the sanding darkens them a fair amount.

That's called "burning". It's entirely different from the rich red-brown
patina that cherry acquires after a few years of exposure to sunlight.