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An Overview of Frame and Mesh Selection

(November 2008) posted on Wed Nov 05, 2008

Choosing the right frame and mesh is critical to achieving quality prints. This overview looks at different frame types, mesh parameters and performance criteria, screen-preparation tips, and recommendations for ensuring long-lasting screens.


By Andy MacDougall

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• Whatever the stencil system, the screen must be cleaned and degreased before each use. Failure to do a proper degrease on the mesh can result in the stencil delaminating or breaking down during the print run. Failure to clean the screen before re-use leaves ghost images and blockages that will haunt your next stencil and cause problems in future prints.

• When not being used for printing, screens should be stored to avoid being accidentally ripped or damaged. During printing, avoid contact with knives or other sharp objects.

• If screens are cared for properly, they can be used over and over, sometimes for years and thousands of impressions, before requiring replacement.

• The two main reasons for replacement are blocked openings that will not come clean and ripping or delamination of the mesh.

• It’s always a good idea to mark the mesh count and age of the screen on the side of the frame, and institute a rotation and replacement system to ensure that screens are always in good shape for printing.

Selecting the right frame and mesh and preparing your screens properly will put you on the path to quality printing more effectively than any other procedure you can perform in the screen-printing workflow. So give your screenmaking process the time and attention it deserves. n

 

Mesh Recommendations by Application

APPLICATION

MESH COUNT (threads/in.)

 

Graphics printing

Line artwork 230 –305

Halftone screens up to 70 lines/in. 305–380

Halftone screens from 70-133 lines/in. 380 –420

 

Objects (plastics, etc.)

Opaque areas 255–305

Halftone and fine lines 305–420

 

Garment printing

Glitter 25–60

Flock adhesive 45–125

Puff-up colors 55–125

Overprint 80 –110

Pigment ink printing,areas/lines 110 –175

Plastisol transfer 125–305

Universal fabric 125

Plastisol direct 125–305

Pigment inks, half-tone 155–255

Sublimation transfer 195–305

 

Textiles, flat films

Heavy décor fabrics (terry cloth, denim) 45–123

Smooth, dense fabrics (table cloths, curtains) 110–155

Light, porous material 195–305

 

Ceramics

Glaze printing, coarse, embossed effect 15–55

Glaze printing, medium to fine 55–155

In and under-glaze (direct printing) 110–255

 

Decals

Areas/lines 195–380

Fine lines/half-tone 255–420

Gold and luster inks 305–420

 

Glass

Automotive glass

Black surrounds for rear/side windows 125–195

Antennas 195–255

Silver paste (defroster) 195–255

 

Architectural glass

Windows, doors 55–195

Mirrors 195–305

 

Cosmetic bottles

Inks 195–305

Precious metals 305–380

 

Beverage

Bottles, glasses 125–305

 

Household

Ovens, etc. (masks) 110 –175

Ovens, etc. (lines and half-tones) 195–255

Lampshades, furniture 125–255

 

Advertising

Shop signs 110 –195

 

Printed circuit boards

Overlay solder mask 30 –45

Photosensitive solder mask 60 –175

 

Membrane keypads and overlays

Insulation lacquer 90 –175

Silver conductive paste 125–175

Adhesive 125–195

Transparent windows 305

 

Andy MacDougall is a screen-printing trainer and consultant based on Vancouver Island in Canada and a member of the Academy of Screen Printing Technology. If you have production problems you’d like to see him address in “Shop Talk,” e-mail your comments and questions to andy@squeegeeville.com.

Editor’s note: This article is was adapted from a section of Andy MacDougall’s new book, Screen Printing Today: The Basics, published by ST Media Group Int’l. The book will be available beginning in mid-November 2008 through ST’s book department and can be ordered online at http://bookstore.stmediagroup.com.

 

 


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