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Electronics => Electronics => Topic started by: corrado33 on July 18, 2011, 03:05:01 PM

Title: Minimum PCB trace thickness for DIYers?
Post by: corrado33 on July 18, 2011, 03:05:01 PM

WOW there are a lot of threads with PCB in the title.   ;)

Only found a few for trace thickness though.

My question is, what is the minimum trace thickness easily achieved by a DIYer making his PCB with an iron or laminator and a laser printer?  Sure, the skill has to be perfected, but it'd be nice to know where to start.  What are your personal experiences?

Not only the pcb trace thickness, but also the "exclusion" distance for polygons etc.  I've already found a point where the printer can't tell two things aren't connected, so that's obviously too close.    

Oh, obviously the trace width should be determined by the amount of current running through it, but let's just guestimate here.  I think the minimum DIY thickness would be plenty thick for most (excluding power) traces. 

Title: Re: Minimum PCB trace thickness for DIYers?
Post by: waltr on July 18, 2011, 03:26:30 PM

Careful, thickness and width are two different dimensions. Copper clad thickness is normally spec'ed by a weight and the common thickness is 1 Oz (ounce) copper which is 0.0014 inch (0.0356mm) thick.

When you are laying out a PCB you specify the trace width. The minimum width will depend on how well your transfer process is.
Even if using a profession board house never use the minimum trace width that can be done. Chose the trace width that to easy to produce.

Re-try the search with "PCB trace width" and you'll get some better hits.

Title: Re: Minimum PCB trace thickness for DIYers?
Post by: vinniewryan on July 19, 2011, 11:59:00 AM

I just made a circuit board where the traces are 0.13mm (width), which is the smallest I've needed so far. I'm sure I could get away with smaller if I needed to, considering how easily I can make these traces on the first try.

I've been etching for a few months, if you know your chemicals it can be very easy to make perfect boards with very small traces. When I first started etching I wasn't very cautions about being clean, so little things like dust or moisture would cause traces to come out looking like swiss cheese.

Title: Re: Minimum PCB trace thickness for DIYers?
Post by: Afroman on July 19, 2011, 06:27:40 PM

For your first few tries I recommend a minimum of 10-12 mils wide.

Title: Re: Minimum PCB trace thickness for DIYers?
Post by: corrado33 on July 19, 2011, 07:00:53 PM

I just designed my first board and all of the traces are above 16 mils, and most of them are 24.  So I think I'll be good.