Building one is on my roundtuit list.
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http://homebuiltedmmachines.com/index.php?page=home has books and PCBs for R/C (Resistor/Capacitor) and Pulse sinker machines. There is also a Yahoo group for discussing the machines at https://groups.yahoo.com/neo/groups/...eBuilders/info
I have the original RC book somewhere
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Or if you're interested in wire, https://groups.yahoo.com/neo/groups/plasmaboog/info although I'm not sure on the current state of available plans.