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Stencil Fiducial Repair

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kpm

#59250

Stencil Fiducial Repair | 10 July, 2009

I have a stencil, on which the fids are no longer black enough for my screen printer to find them. A long time ago at a previous place of employment we had a loctite product to fill these in as a permanent solution. I have since forgotten the part number of the loctite used and was hoping someone could recommend a product they use for this, other than a sharpie or paint pen because our sonic cleaner removes these instantly. Thanks for the help

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#59251

Stencil Fiducial Repair | 10 July, 2009

If they are under filled fids, take heavy duty two part epoxy and mix it with carbon powder from your copier. Use a razor blade to carefully trowel it in.

We now use laser etched fids. They are much better.

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#59266

Stencil Fiducial Repair | 13 July, 2009

Here is something I found , I hope it helps :

Subject: Re: Repair of fiducial fill material From: Taylor, Royce Reply-To: TechNet E-Mail Forum. Date: Fri, 15 Dec 2000 09:34:59 -0500 Content-Type: text/plain

I use a epoxy pen that my stencil house gave me

it says:

HEAT CURE EPOXY INK AM-33 HC-883 BLACK For Professional Use Only, Made in USA

It does not give the vendor.

I fill the fiducial and "CAREFULLY" heat the area with a heat gun, works great, but it doesn't last forever..

Royce Taylor Engineering Manager Sanmina Corporation 10 Manor Parkway Salem, NH 03079 (603) 896-2192 (603) 896-2063 royce.taylor@sanmina.com

-----Original Message----- From: Julien Bouchard [mailto:julien.bouchard@matrox.com] Sent: Friday, December 15, 2000 7:39 AM To: TechNet@IPC.ORG Subject: Re: [TN] Repair of fiducial fill material

Thank you for your answer, it should really help. But what is the loctite 4501 ? I found nothing about this on the loctite web site ? IS a cyanocrilate or an epoxy base glue ?

-----Original Message----- From: TechNet [mailto:TechNet@IPC.ORG]On Behalf Of Joe V. Ottesen Sent: 15-Dec-00 02:21 To: TechNet@IPC.ORG Subject: Re: [TN] Repair of fiducial fill material

Julien Bouchard wrote:

> Hi everybody, > We recently start to use an ultrasonic stencil cleaners for our stencils. > It' work well, but after some time, we saw a lot of fiducial that the black > epoxy have been partially or totaly remove. I want to know if someone had a > similar problem with a stencil cleaner. Also, we looking for a material to > repair the black epoxy of the fiducial ( for now we use ink pen, but we need > to redo the job everytime we change of product). Our stencil are from UTZ > and our stencil cleaner is from SMART-SONIC. Thank you. > > Julien Bouchard > Matrox - Process Engineer > Email : julien.bouchard@matrox.com > > -------------------------------------------------------------------------- ------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8d > To unsubscribe, send a message to LISTSERV@IPC.ORG with following text in > the BODY (NOT the subject field): SIGNOFF Technet > Search previous postings at: http://www.ipc.org > On-Line Resources & Databases > E-mail Archives > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information, or contact Keach Sasamori at sasako@ipc.org or 847-509-9700 ext.5315 > -------------------------------------------------------------------------- -------

Hi,

I have also seen the problem, with the same cleaning equipment. To repair the fiducial and get the best contrast we use a Loctite 4501 kit. Today our stencil deliverer is pigmenting the metal in the half etched fiducial mark and it works like a dream.

-- best regards Joe Vella jvo@bbelectronics.dk Website http://www.bbelectronics.dk

HCarrasco

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#59292

Stencil Fiducial Repair | 15 July, 2009

Have used a Loctite product called Blacktak (or similar) previously for permanently replacing fiducials.

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#59368

Stencil Fiducial Repair | 23 July, 2009

Hi PPM! Have your stencil house mark fid with laser machine - that how we use to have fid mark once it marked with laser it last very long time like stencil's life.

Good luck!

Steve USA STENCILS INC

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#59380

Stencil Fiducial Repair | 24 July, 2009

The issue is not with the stencil cleaner, it is with the construction of the fiducial.

Ultrasonics is very effective in cleaning and penetrating into small microscopic cracks and crevices (this is one reason why ultrasonic stencil cleaners are so efficient in cleaning fine-pitch stencils). If the epoxy is not applied properly, the ultrasonics will deliver the wash solution into any cracks and crevices and begin to loosen the epoxy. The fiducial cut needs to be cleaned properly prior to applying the epoxy to allow proper adhesion. If not, the epoxy will fail after several cleanings.

One solution would be to cut the fiducial into a “trapezoid” shape. When the epoxy dries, it will not be able to escape even if applied inappropriately.

If you should have any questions, please contact me directly.

Bill Schreiber, President

Smart Sonic Stencil Cleaning Systems.

Bill@SmartSonic.com

www.SmartSonic.com

Tel: +1-818-610-7900

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