[TheForge] interesting project

[terry l. ridder]

hello;

this runs counter to what i have been told by two automobile body shops
that specialize in depainting automobiles down to bare metal. their main
comments were to use cool and dry compressed air and a larger nozzle
then would be used for the typical abrasive media.

as for cool dry air, we all ready have liquid nitrogen available. a
small vaporizer would supply cool dry nitrogen at the correct pressure.
nozzles are not really a problem either. the one automobile body shop is
willing to sell us the coarse baking soda at his cost.

their additional comments had more to do with a side-effect which they
do not normally run into but have heard from others who use soda
blasting to remove graffit. while baking soda is non-toxic and
environmentally safe in large amounts it can change the ph balance of
soil and ruin landscaping. (plants, lawn, etc). they suggested using a
tarp to keep the baking soda out of the landscaped areas. i would assume
that this applies to acidic soil. would be like vinegar and baking soda
reaction. i am not sure if it would alter a basic soil.

other than that they said common-sense safety practices are sufficient.
(respirator, full face shield, hearing protection, warning signs, etc)

On Tue, 20 May 2003, Paul Hewitt wrote:

paul> 
paul> Ahh there is a problematic question, we purchase from distributors, and they
paul> ar epretty tight about only selling to people with the right equipment, its
paul> about 5000.00 or more for the right equipment because of the way soda
paul> "shears" it won't work in ordinary sand blasting equipment.
paul> 
paul> 

-- 
Terry L. Ridder ><>