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Shrinking auto body forming tools

I’ve been online researching metal and metal working and learned
that people who work with auto body use what is called a slapper. Is
anyone familiar with this? Do you think it would be useful smaller
for forming small metalsmithing pieces? Try googling this tool.


If you are making large pieces… really large pieces, then a
slapper can work. If you reduced the size of the tool then it would
become ineffective, as you wouldn’t be able to “slap” the work.

Look more into plannishing, and shrinking hammers, also used in body
shops, but the techniques for using those are transferable.

Regards Charles A.

By slapping (slight compression) of a hot spot (1" circle of hot
metal) on auto body sheet metal the slapped area will shrink slightly
upon cooling. This technique is applied while shaping a compound
curve. I used this technique on the rear quarter panel of a 1971
Karmann Ghia. It worked. I used a dolly, planishing hammer, and
Oxy/Acetylene. I don’t think the technique would be useful on small
objects. I’m not a silversmith, so I can’t speak to silver sheet

a slapper is like a “spoon” a long piece of case hardened steel
somewhat rounded on the ends, though there are different shapes and
about 12-16 " long, 2-3 " wide… you can get them and dollys as well
at harbour freight along with some great hammers - the forming tools
(dollys) and other items in their auto body offerings are great for
metal fabrication. I found some good mini stakes there that are
threaded and perfect for many many applications in the studio- just
remove the baked on enamel and thread your own rod that can be held
in a grs benchmate or anvil/vise…keep 'em highly polished and coated
with a quality wax or oil to protect them from humidity and they will
serve you as well as peddinghaus tools for as long a period as those
will last at a fraction of the cost!..rer