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PDA 06 5/27/03 8:37 AM Page 111
Chapter 6 / Building PDA Robot
Figure 6.4
Cutting out the
circuit board
artwork.

tact with eyes and skin. Flush thoroughly with water for 15 minutes if
it is splashed in the eyes or on the skin.

Using rubber gloves and eye protection, dilute one part M.G. cat. #418
developer with 10 parts of tepid water (weaker is better than stronger)
in a plastic tray. Immerse the board copper side up into the developer,
and you will quickly see an image appear while you are lightly brush-
ing the resist with a foam brush. This should be completed within one
to two minutes. Immediately neutralize development action by rinsing
the board with water. The exposed resist must be removed from the
board as soon as possible. When you are done with the developing
stage, the only resist remaining will be covering what you want your
circuit to be. Completely remove the rest.

Note: Ensure that the mixture of water and developer is mixed thor-
oughly. If it is not, the traces may wash away when the board comes
in contact with a pocket of highly concentrated developer.

Etching Your Board. For best results, use the 416-E Professional
Etching Process Kit or 416-ES Economy Etching Kit. The most popu-
lar etchant is ferric chloride, M.G. cat. #415, an aqueous solution that
dissolves most metals. Use this solution undiluted, and be sure to
completely cover your board.

Warning: This solution is normally heated up during use, generating
unpleasant and caustic vapors. It is very important to have adequate
ventilation. Use only glass or plastic containers. Keep out of reach of
children. It may cause burns or stain. Avoid contact with skin, eyes,

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