TECHNET Archives

March 2014

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Jack Crawford <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Jack Crawford <[log in to unmask]>
Date:
Tue, 18 Mar 2014 16:03:39 +0000
Content-Type:
text/plain
Parts/Attachments:
text/plain (1 lines)
People just don't realize that J-STD-001 and IPC-A-610 and not design standards.



Jack Crawford

Certification and Assembly Technology

IPC – Association Connecting Electronic Industries®

3000 Lakeside Dr. Suite 309S

Bannockburn, IL 60015

847-597-2893

Fax 847-615-5693

[log in to unmask]

www.ipc.org

www.ipc.org/status  www.ipc.org/certification  www.ipc.org/downloads



-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of Whittaker, Dewey (EHCOE)

Sent: Tuesday, March 18, 2014 9:41 AM

To: Technet

Subject: Re: [TN] Confusion about conformal coating area



Conformal coating is art on to itself. When PBAs are designed with specific coating systems in mind; relative bliss. When your ISC department gets hold of them and outsources them to Benny and Gill's Hash House; indigestion is the least of your worries. All the PBAs should (I really wanted to say shall) be controlled by the Drawing and Engineering support documentation. Below is set of Conformal Coat notes for PBA drawings.







NOTE 7. COAT ASSEMBLY PER Item/FN (Manufacturing specification for Conformal Coating listed in the BOM) USING Item  Item/FN (Material Code Number of the Conformal Coat material), UNLESS OTHERWISE SPECIFIED:

7.1. OMIT COATING FROM AREA OUTSIDE OF PHANTOM LINE,

ALL AROUND, BOTH SIDES.

7.2. OMIT COATING FROM BODY OF Item/FN (part identification on BOM).

7.3. OMIT COATING FROM PRIMARY SIDE OF Item/FN (part identification on BOM).

7.4. OMIT COATING FROM ADJUSTING SCREW ON Item/FN (part identification on BOM).

7.5. OMIT COATING THIS AREA, BOTH SIDES.

7.6 COATING MAY OR MAY NOT BE PRESENT IN NON-CRITICAL

LAMINATE AREAS OF Item/FN (part identification on BOM) OR ON THE TOP AND SIDE

OF THE NON-CRITICAL, NON-CONDUCTIVE SURFACES OF

LARGE SCALE PACKAGES, UNLESS OTHERWISE

SPECIFIED. THIS EXCEPTION IS FOR THE COATING

COVERAGE REQUIREMENT AND SHALL NOT BE USED TO

ACCEPT UNCOATED AREAS DUE TO BUBBLES, VOIDS AND

OTHER WORKMANSHIP ISSUES.



This appeases Engineering that all critical areas are covered and is simple enough that even ISC and the Supplier can understand the requirement.



Dewey











-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of lduso - Diamond-MT.com

Sent: Monday, March 17, 2014 2:37 PM

To: [log in to unmask]

Subject: Re: [TN] Confusion about conformal coating area



That's always been the confusing part, there needs to be a third area in the "plain language". Coating where it *needs* to be, no coating where it

*cannot* be, and areas where coating *can* be, but doesn't *have *to be.



Coating can (and often does) de-wet on top of component or de-wets out in the middle of the soldermask, no place that requires coating but somewhere that is not worth masking. Is that a reject?



Lloyd Duso

Diamond-MT

Plant Manager

(814) 535-3505

www.Diamond-mt.com





On Mon, Mar 17, 2014 at 5:15 PM, Jack Crawford <[log in to unmask]> wrote:



> The plain language requirements for conformal coating are:

> Coating shall be where it is required to be, and there shall not be 

> any coating where it isn't required.

>

> J-STD-001E Clause 10.1.1 Application Coating shall [D1D2D3] be applied 

> in a continuous manner TO ALL AREAS DESIGNATED FOR COVERAGE ON THE 

> ASSEMBLY DRAWING/DOCUMENTATION.

>

> IPC-A-610E Clause 10.8.2 Acceptable - Class 1,2,3 Coating only in 

> those areas WHERE COATING IS REQUIRED. Defect - Class 1,2,3 Coating is 

> on areas required to be free of coating, e.g., mating surfaces, 

> adjustable hardware, wicking into connector housings, etc.

>

> If the drawings/documentation don't require coating J-STD-001 and

> IPC-A-610 don't separately cause a requirement for coating.

>

> Jack Crawford

> Certification and Assembly Technology

> IPC - Association Connecting Electronic Industries®

> 3000 Lakeside Dr. Suite 309S

> Bannockburn, IL 60015

> 847-597-2893

> Fax 847-615-5693

> [log in to unmask]

> www.ipc.org

> www.ipc.org/status  www.ipc.org/certification  www.ipc.org/downloads

>

> -----Original Message-----

> From: TechNet [mailto:[log in to unmask]] On Behalf Of Richard Kraszewski

> Sent: Sunday, March 16, 2014 5:44 PM

> To: Technet

> Subject: Re: [TN] Confusion about conformal coating area

>

> You and your organization are not the only ones being driven crazy by 

> this these specifications. Current J-Std-001 leads you to believe all 

> must be coated.  The A610 seems to  make better use of the  acronym AABUS (as

> agreed between user and supplier).   In my experience, you can sometimes

> explain and convince  the customer that there is little value in 

> coating the side of  molded components. Only try electrical conductors.

>

> More often than not, this is easier  done at the start of a program  

> rather than after the fact.

>

> Rich Kraszewski

> PLEXUS

> (920)969-6075

>

>

> -----Original Message-----

> From: TechNet [mailto:[log in to unmask]] On Behalf Of Çetin Yegin

> Sent: Friday, March 14, 2014 3:02 AM

> To: [log in to unmask]

> Subject: [TN] Confusion about conformal coating area

>

> Dear All,

>

> We have a confusion about conformal coating area. Our quality 

> department rejects some boards because edges of some high components were not coated.

> These edges are non-conductive and I think there is no need to coat 

> non-conductive areas. IPC-A-610 10.5.2 says that "Conformal coatings 

> should be transparent, uniform in color and consistency and uniform 

> cover the board and components".

>

> 1.       Does it mean we have to coat all areas unless specified in design

> document?

>

> 2.       Is there any requirement to coat non-conductive areas?

>

> 3.       Do we have to coat non-conductive areas of components?

>

>

> Thanks.

>

> Best Regards

>

> Çetin YEĞİN

> Senior Engineer

>

> ASELSAN A.S. \ ASELSAN INC.

> Microelectronics, Guidance and Electro-Optics Division (MGEO) Çankırı 

> Yolu, 7. km, 06750 AKYURT, ANKARA, TURKEY

> Phone: +90 (312) 847 53 00 Ext:4071

> Fax: +90 (312) 847 53 20

>

>

> ______________________________________________________________________

> This email has been scanned by the Symantec Email Security.cloud service.

> For more information please contact helpdesk at x2960 or 

> [log in to unmask] 

> ______________________________________________________________________

>

> ______________________________________________________________________

> This email has been scanned by the Symantec Email Security.cloud service.

> For more information please contact helpdesk at x2960 or 

> [log in to unmask] 

> ______________________________________________________________________

>



______________________________________________________________________

This email has been scanned by the Symantec Email Security.cloud service.

For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________



______________________________________________________________________

This email has been scanned by the Symantec Email Security.cloud service.

For more information please contact helpdesk at x2960 or [log in to unmask] 

______________________________________________________________________


ATOM RSS1 RSS2