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Subject: Re: RE : [Homebrew_PCBs] CNC tools

From: uhmgawa <uhmgawa@...>
Date: 2005-06-27

derekhawkins wrote:
>>With the cost of solder paste in prototype
>>quantities somewhere between $25-40 per 250gm a more
>>conservative approach is quite attractive.
>
>
> So you believe this is the same thing board manufacturers use in bulk
> hence more affordable to them? I doubt it.

It is the same solder paste formulation. Otherwise
why sample it for pre-production/prototype qualification?

Note the amount of solder paste consumed in a printing
operation is relatively small compared to the bulk
required to load the stencil before the print is made.
New paste is added to the bulk as it is consumed.

The process of warming the paste to room temperature
as well as the printing operation results in gradual
degradation. This is acceptable in a production
operation where the waste is amortized amongst a series
of boards but inefficient for prototype work.

--
uhmgawa@... www.gnu.org