11 twist and bow and pcb and ipc and 0.75 results

Electronics Forum: twist and bow and pcb and ipc and 0.75 (Page 1 of 2)

PCB assembly bow and twist

Electronics Forum | Thu Dec 26 12:12:55 EST 2013 | igorfo

Dear Friends, I need your help to understand requirements and measurement methods for bow and twist of assembled PCB (PCBA have and SMT and TH components). I already check all posts on the site but didn't found any related to my question answers.

Bow and twist of PCB's

Electronics Forum | Mon Apr 23 11:44:55 EDT 2001 | CAL

650 Standards are also located in the back of IPC JSTD-001. I am currently looking at 4 pages on bow and twist. Percent bow = R1-R2/L x 100 (R1= Highest point; R2=lowest or resting point; l= length) Percent twist=(R1-R2)/(2xL)x 100 Sorry if this is

Bow and twist of PCB's

Electronics Forum | Mon Apr 23 14:03:18 EDT 2001 | Ryan Jennens

Dougie- We,too, have the IPC-A-600F, and the spec. refers to IPC-TM-650 test method in the back of the book. Look on page Number 2.4.22 of the test methods appendix. This outlines the procedure for determining the percentage of bow and twist,

Bow and twist of PCB's

Electronics Forum | Fri Apr 20 07:12:22 EDT 2001 | wbu

Dougie, oh yes, it�s a bit short that chapter. I have the Revision e in front of me and this one contains in the appendix the needed IPC-TM-650 Test method for bow and twist. Can�t think that they don�t have that in the new revision. Hope you find

Bow and twist of PCB's

Electronics Forum | Fri Apr 20 13:55:09 EDT 2001 | kawiederhold

Hey Dougie, If you go to IPC.ORG and click on the on-line resources and databases, then on the "free downloads" link, the second or third document "for free" is the IPC-TM-650 in its entirety. It does discuss the test you are looking for! Have fun

Bow and twist of PCB's

Electronics Forum | Fri Apr 20 05:32:39 EDT 2001 | dougie

Hi, I've just splashed out �60 on IPC-A-600F trying to find out the formula for measuring the bow and twist of raw PCB's. Much to my dismay there are 10 lines on the subject in the whole standard. Worse still is that it tells me nothing I don't alre

Bow and Twist of PCB's

Electronics Forum | Wed Aug 19 05:00:56 EDT 1998 | Tom Blum

Hi there, I'm actually facing a lot of trouble with PCB's presenting up to 3mm of bow /twist at reception i.e. before assembly. The PCB size is 220 by 230mm. The boards are to be assembeled SMD double sides with 05.mm pitch on both sides. In order to

Standard of PCB Bow and Twist in Incoming Inspecion

Electronics Forum | Thu Feb 27 12:27:10 EST 2003 | stevel

Hi all, We got some bare pwb in our incoming inspecion looked really wrapped. The maximum twist of the pwb we messured is 0.056inch by following the method in IPC-TM-650 2.4.22 C. (The diagonal size of our pwb is 7.5inch) According to the IPC standa

Standard of PCB Bow and Twist in Incoming Inspecion

Electronics Forum | Fri Feb 28 09:08:03 EST 2003 | davef

Without drilling through the numbers, they're probably correct. Recognize that standard warp / twist specs [IPC-A-610 1.5% for PTH only and 0.75% for SMT] are not going to make it on tech boards. You need to define specific requirements. This warp

Re: Bow and Twist of PCB's

Electronics Forum | Wed Aug 19 12:20:24 EDT 1998 | MARK J.

| Hi there, | I'm actually facing a lot of trouble with PCB's presenting up to 3mm of bow /twist at reception i.e. before assembly. The PCB size is 220 by 230mm. The boards are to be assembeled SMD double sides with 05.mm pitch on both sides. In orde