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Showing posts from April, 2007

Measuring TIR Spindle Bearing Runout On Your CNC Machine

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Spindle Runout Problems Can Be Your Hidden Quality Issues In Building Reliable Printed Circuit Boards The simple definition of spindle radial runout is how much wobble a spindle produces at the nose. Axial runout is the measurement of how much play there is perpendicular to the axis of rotation. The reading is represented by Total Indicated Runout, TIR, which means the distance measured between the largest plus direction and the largest minus direction for a total indicated amount. A spindle can be measured either dynamically (at speed) or statically. The dynamic measurement is by far, the most accurate and requires special non-contact measuring devices. Today's air bearing spindles have gotten faster with higher precision than the ball bearing spindles of the past. Air bearing PCB spindles can typically be found running in the 120K RPM through 180K RPM ranges, with some spindles running up at 300,000 RPMs. Since the spindle air bearings are floating on air, no mechanical contact...

Checkout Used Excellon Equipment Before Buying

Everyone wants a great deal on Excellon machines or any used equipment. With many circuit board shops closing down, and their equipment being auctioned off, it is wise to have the machines checked out before buying. The Tale Of The Uninformed Used Equipment Purchase Excellon, Kennard, PDA, Pluritec, Hitachi, Mania, Klingelnberg, Advanced Controls, Trudrill, ESI, Dynamotion, ATI, Wessel, DAC, and other PCB drilling and fabrication equipment, that supposedly were running before being shut down have cost thousands of dollars to the unsuspecting buyer when buying blindly online through an auction or even the buyer looking at the machine in person. Instead of having a qualified and experienced service technician inspect the machines, buyers go it alone. Buyers think they are getting a great deal, but many times what they are getting is a big boat anchor. The outside of the machines can look all beautiful and cleaned up, while the inside is falling apart. We have seen machines that looked l...