Well, you ask a lot here. Most of this is in “Studio Preparation and
Coloring of Titanium” available from RMS <reactivemetals.com>. Heat
coloring is not an exact science. Anodizing is pretictable. With
heat you have too many variables to say when or how long it will
take to get a color.
What is the better way to clean the surface before colouring?
Best is chemically. HF and nitric acids. You do not want to do it!
VERY DANGEROUS chemicals. RMS has a “MultiEtch” product that does
pretty well. Otherwise ScotchBrite is good and store in water until
you are ready to color. And keep it absolutely clean, wear gloves!
Is there any material i could use for "masking" some parts?
Any thing that won’t burn. Even particles of metal sprinkled on the
surface. Clay, ocher, white out…
What material can i use for holding up the piece, that wont
melt, dissipate much heat or create different colors (because of
the temperature) on the piece?
Make some trivets from titanium sheet or hang from a wire… That is
probably the best you can do.
Does anyone have a chart with the temperatures for coloring
titanium in a kiln?
It will depend on your kiln, preheating, the thickness of the
titanium and how it is held. Make your own chart based the equipment
you are using. It is a time/temperature relationship. Very difficult
to control.
Any tips for achieving an even colour when torch coloring?
Practice.
What is the effect when you re-heat a piece that has already
been colored (like, lets say, magenta temperature)? Will it
continue oxidizing to the next levels of colour?
The oxides gets thicker, changing the color to the higher
temperature level. So, yes, you can grow it to the next highest.
Never back to a lower.
In that case, how can i get different oxidizing colours on the same
piece?
Use a flex shaft, engraver, sand paper, whatever, to remove the
color and do a lower temperature/time color in the fresh metal. You
must remove the color and maybe some surface metal to get back to
clean material. Oxygen is absorbed into the surface of the metal. It
may look clean but color uneven due to surface absorption.
With heat, you get what you get. It is serendipity. Play, have fun
with it but try not to get too serious. Then when you get really
frustrated try anodizing. It makes all the control you are asking
for so much easier.Bill
Welcome to Reactive Metals Studio, Inc. Our catalog site is
<www.reactivemetals.com>. Thanks for making contact. Stephanie, Bill,
Deborah, Michele. 800/876-3434, 928/634-3434, Fax 928/634-6734