Hi, Ted,
Thanks for your kindly response. According to your advice, I still not very clear about (S,S,P,S,S,P,S,S correct/ S,P,P,S,S,S,S wrong).Could you help me again? By the way, could you tell me what parameter is fit for double side rigid PCB with 1 oz copper and 2116 P.P?
thks,
George
----- Original Message -----
发件人: "Ted Tontis" <[log in to unmask]>
收件人: <[log in to unmask]>
发送时间: 2001年3月17日 George 00:25
主题: Re: [TN] twist and wrap issue
> George,
>
> The most common reason for warp and twist is tempter. If a board
> cools unevenly then the board might warp and twist. Best way to avoid this
> is to make sure that your layer stack up must be symmetrical apposed to
> asymmetrical.
> (S,S,P,S,S,P,S,S correct/ S,P,P,S,S,S,S wrong). If the edges of the board
> cool before the center has a chance too then it will warp, after lamination.
> If this is the problem then you should be able to heat the board up and cool
> it down slower and relive the problem. It can also be that there is an
> uneven amount of resin on the board.
>
> I hope this answers you question,
>
> Ted
>
> -----Original Message-----
> From: Nancy Trumbull [mailto:[log in to unmask]]
> Sent: Friday, March 16, 2001 5:42 AM
> To: [log in to unmask]
> Subject: Re: [TN] twist and wrap issue
>
>
> Sorry George,
> What it is you what to know.
> Your question is not clear.
> Nancy T.
>
> >>> [log in to unmask] 03/15/01 09:31PM >>>
> Hello, Everyone
>
> Does anyone kindly help me explain the reason for wrap and twist of rigid
> PCB?
> I'm appreciate your generous guidance and your any advice.
>
> George Chu
> Quality Dept.
> Phone: ++86 512 5651961 ext.6201
> Fax: ++86 512 5613446
> Email: [log in to unmask]
>
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