DIY Pcb questions..

[Chris_P]

Hey all,

Im interested in using some homemade PCB for a couple of sections in my new amp.. the relay power supply (powered off 6.3vac) & possibly the circuit for the DC heaters, running of a 24vac 1A tranny. I wont be modifiying these parts & I have limited space available, so PCB seems like it could be the answer. Ive read about a couple of methods for producing the PCB from some copper clad board, seems pretty straitforward.. but.. Im wondering, how do I work out the thickness of the trace required? I dont wana go crazy small or anything, but at the same time, I dont wana turn the thing on & risk having the trace burn up!

Chris.

[Haze13]

Search in the google for a "Trace thickness table" or calcultator...
Take a look at Soldano/Jet City pcb and there you'll find every thing that you need.

[pcbman]

PCB material FR-4
Board thickness=1.6mm
Trace thickness or copper weight=1 oz.
Allowed temperature rise=10 °C

According to recommendations in IPC-2221, minimum PCB trace width and current in ampere should be as below:
Current in Ampere Width (Outer) in Mils
0.1 1.18
0.2 2.37
0.4 4.73
0.4 4.73
0.5 5.91
0.6 7.1
0.7 8.28
0.8 9.46
0.9 10.6
1.0 11.8

Thumb rule: Always use trace width greater than standard mention value.

PCB Assembly service

[demonufo]

Also to be considered is voltage, and space between traces when using higher voltages. Although if your strictly talking about relay and heater supply it's not so much an issue as plate voltage would be.

[Haze13]

And no straight corners! As round as possible. Like that, but with thicker traces. And separate grounds too