Here's a possible solution....try K&J Marketing. They sell a KEPOCH stencil.
It is made of a plastic-type material. Almost like Kapton. It is see-through
(amber color), therefore, visual alignment is enhanced. It is chemical
resistant, has no sag or resiliency problems, and best of all, when cut, it
is smooth in the apertures. Hence, there are no release problems. Website is
www.kjmarketing.com. Also, Steve G.'s advice of 1.5 to 1 ratio is good. Hope
this helps.
> -----Original Message-----
> From: Steffen, Don E [SMTP:[log in to unmask]]
> Sent: Wednesday, September 22, 1999 12:24 PM
> To: [log in to unmask]
> Subject: [TN] Need to know
>
> Technetters
>
> I have a situation where I need the advice from the Technetters. I have an
> assembly with HASL. In order to stay within the aspect ratio guidelines, I
> must use a stencil that has a .0085 aperature opening, a 20 mil spacing,
> and
> I must use a 6 mil stencil. I tried this and when the stencil pulled away,
> the surface tension pulled away the solder paste from the pad area. If I
> were to go to a 5 mil stencil (which is outside the Aspect Ratio
> guidelines), would this help me with keeping the solder paste on the pad
> and
> not on the stencil? Or is there another approach that I should consider
> instead of going to another stencil thickness? Any help you can give me
> would be appreciated
>
> Donn E Steffen
> Senior Quality Engineer
> VDO Control Systems
> Auburn, IN 46706
> Phone (219)925-8887
> Fax (219)925-8710
> Email: [log in to unmask]
>
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