Homebrew PCBs

christiansen_alex@... wrote:
> --- In Homebrew_PCBs@yahoogroups.com, "leon Heller" <leon355@...> wrote:
>   
>> ----- Original Message ----- 
>> From: "Simao Cardoso" <simaocardoso@...>
>> To: <Homebrew_PCBs@yahoogroups.com>
>> Sent: Sunday, December 06, 2009 9:30 PM
>> Subject: Re: [Homebrew_PCBs] 105 u copper needed
>>
>>
>>     
>>> Simao Cardoso wrote:
>>>
>>>       
>>>> known as 3 oz/in²
>>>>         
>>> What a mistake, I may dislike imperial units but this was, how to say, a
>>> shoot in the _foot_?   :>
>>>       
>> Etching would take a very long time with 3 oz/sq. inch copper. I make it 
>> about 1.5 mm thick. 8-)
>>
>> Leon
>>
>>     
> thanks all for intersting reply :) 
> and Leon ,yes I know its not easy to get..that's why I asked here,as I have noticed that much can happen here in this group :)
>
> If I get it..it might be a problem with etching.. or scould it not be the same ..except the time. 
> I dont understand the last line "I make it about 1.5mm thick 8) ??
> ,maybe not important ,but if it is.. please tell me again..
> alex
>   

Copper is measured in ounces per square foot, not per square inch.  3 
ounces per square inch would be 15 mm thick (not 1.5) and a 12 inch 
square board would weigh 27 pounds, or about 12 kilos.  He was being funny.

Kerry