Adam,
I agree with Jerry's take on the issue. We allow a lot of clearance 0.1" (2.54
mm) as we have found our through-hole wave soldering assembly houses have
problems gripping the boards. Since we adopted that we have had no more
complaints. Also, when it comes to handling the boards in anti-static board
racks, there needs to be at least one edge clear of components so the boards
will fit the slots of the racks. It is these kinds of issues you need to
consider so look into your assy & test handling procedures and see that
all their needs are satisified if you can. Of course, those that use break-away
type assy don't have these problems to deal with. We don't use that kind of
processing.
Bob Landman
H&L Instruments L.L.C.
Electro-Optics for Industry & Science
34 Post Road, PO Box 580
North Hampton, NH 03862
tel(603)964-1818 fax(603)964-8881
http://www.hlinstruments.com
----- Original Message -----
From: Jerry Galang <[log in to unmask]>
To: <[log in to unmask]>
Sent: September 30, 1999 11:03 AM
Subject: Re: [DC] Just Curious....
> Adam,
> What really counts is your assembly house and of course the mechanical
> restraints of the enclosure that the board resides in.
> We design on mostly PCMCIA form factor, components are a minimum of 1,27mm
> (although we break this rule ocassionally). 99% of our production is panelized
> and on the ones that are scored for separation the same rules apply only from
> the edge of the score.
>
> Have fun, keep smiling!
>
> Jerry Galang
> PCB Designer/Librarian
> Xircom
> 2300 Corporate Center Drive
> Thousand Oaks, CA 91320
> 805.376.6684 ph
> 805.376.9311 fax
> [log in to unmask] email
>
>
>
>
>
> From: "Hawes, Adam" <[log in to unmask]> on 09/30/99 01:52 PM GMT
>
> Please respond to "DesignerCouncil E-Mail Forum." <[log in to unmask]>;
> Please respond to "Hawes, Adam" <[log in to unmask]>
> To: DesignerCouncil
> cc: (bcc: Jerry Galang/ThousandOaks/Xircom)
> Subject: [DC] Just Curious....
>
>
>
>
> What do you guys use as a std,rule of thumb package keepin from the edge of
> a PCB. We are using 1.5mm as standard but I have (the usual story) a small
> PCB with alot of components to get on! Any feedback from other designers and
> fabricators would be greatly appreciated.
>
> Regards,
>
>
>
> Adam Hawes GenRad Ltd.
> PCB Design Engineer, Orion Business Park,
> Bird
> Hall Lane,
>
> Cheadle Heath,
> Tel: 0161 491 9290 Stockport,
> Fax: 0161 491 9106 SK3 0XG.
>
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