MAGAZINE ARTICLES

PRINTWEAR MAGAZINE

SCREEN PRINTING MAGAZINE

THE PRESS REPORTS

PRODUCT ARTICLES

NEWMAN CONSTANT FORCE SQUEEGEES

Spot Light on:

 Don Newman

October 1993

Part I
Tuning Up Tension
November 1993

Part II
Spaghetti with Rubber Bands
December 1993

Part III January 1994

Part V
April 1994

Part IV February 1994

Part VI
June 1994

Part VII
August 1994

PRODUCT ARTICLES

NEWMAN
"CONSTANT FORCE"
 SQUEEGEES^TM

     After 12 years of developing the economical NEWMAN CONSTANT FORCE SQUEEGEE^TM (on average 1/2 the cost of a conventional squeegee) the squeegee is no longer a variable.
     The conventional squeegee varies its length due to sharpening combined with solvent attack, which changes the flex angle of attack on the ink.  This changes the pressure on the ink significantly during long print runs and between subsequent print runs. Like screen tension, the conventional squeegee is a larger and more significant variable than first meets the eye.
     The NEWMAN CONSTANT FORCE SQUEEGEE^TM has constant length since it is not sharpened; the entire tip is simply exchanged.  The Squeegee Holder also cannot be attacked by ink chemistries like conventional squeegee, which gradually change their flex angle. This new squeegee has constant length, constant flex angle and constant pressure on the ink every time you use it.
     You will achieve faster set-up times because there is no need to adjust the squeegee up or down due to the length of different squeegee according to how many times the squeegee has been sharpened.
     The replacement tips, in various durometers, are made of specially formulated urethane and for many applications will last 6 months to 2 years.
     1/8" sharpening of a conventional squeegee radically changes the squeegee stiffness, flex angle, angle of attach on the ink, and the required pressure on the ink. As the conventional squeegee becomes shorter from sharpening, the squeegee increase its stiffness dramatically – not directly proportionately – but changes by the 3^rd power of the new shorter length (L³).
     By example: a 75 durometer squeegee with 1.2" length (past the holder) with flex approximated 3/8" with 5 lbs./inch of pressure.  By sharpening the squeegee to 1.0" long, the same 5 lbs./inch of pressure causes the squeegee to stand up straighter with only approximately 1/8" flex.  To bring the flex back to 3/8", now about 30 lbs./inch of squeegee pressure is required. This will change the ink deposit and detail. The approximate numbers vary greatly with various screen tensions, off-contact, ink rheology, squeegee durometer and type, print speeds, substrate variations, and aesthetic goals.
     These approximate numbers and the general pictures below are provided for the purpose of conceptionalization only.

     Remember that new technology is rarely a quick fix.  Improvements in print quality and speed usually comes at the price of hard work, testing, and an open mind to new possibilities.  The printers that get better and faster every year are constantly testing, working harder, applying constant creativity, and more persistence than their competitors might think.

Data reference Equation: D = PL³
                                         3EI
                                                               Prepared and written by Don Newman  October 1997