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11 Benchmark Test Technical Training E by DEK 12/2017 105 SPC Data Cycle Time L-R or R-L Cycle time 1 (Left to Right/Right to Left) is time from board being received from Upline to same board being re- leased to Downli…
11 Benchmark Test
104 Technical Training E by DEK 12/2017
SPC Data Alignment Error
Depending on how the printer has been set-up for SPC output (pre or post or both), the camera will
capture each fiducial in turn. This positional data is sent to the computer for it to calculate the X, Y
and theta alignment error outputs for SPC analysis.
This data is captured just before the print stroke but after the alignment process if "pre" is selected
or after the print stroke if ‘post’ is selected. This data is captured on both occasions if "both" is
selected.
The computer then calculates the alignment error for X, Y and theta and sends it out as SPC
information.
NOTICE
This information for SPC is output just before the print stroke but after the alignment pro-
cess, and/ or just after the print stroke.
Board Stretch
Board stretch is calculated by taking the point of location of stencil fiducials and calculating the dis-
tance between them. Then the point of location of board fiducials and calculating the distance
between them. The difference between these is board stretch. It will be positive if stencil fiducials
are further apart than board fiducials.
Pre and post fiducial X and Y errors are calculated as shown in above diagram by finding positional
difference between each stencil and board fiducial. This can be done either before or after print, but
must be done after alignment. This information is used to calculate X, Y and theta alignment data.
This can be illustrated by running several prints with SPC outputs (alignment weighting set to 50%)
then changing the alignment weighting to 100% or 0% and observing the change. If set to 100%,
fiducial 1 error´s will move closer to zero and if set to 0% fiducial 2 errors will move closer to zero.
Stencil (mm) – Board (mm)
= Board Stretch
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Technical Training E by DEK 12/2017 105
SPC Data Cycle Time L-R or R-L
Cycle time 1
(Left to Right/Right to Left) is time from board being received from Upline to same board being re-
leased to Downline.
●
Board Received by Machine
= Cycle Time starts
●
Board Exits Machine
= Cycle Time stops
SPC Data Cycle Time R-R or L-L
Cycle time 2
(Left to Left/Right to Right) is time from board arriving at board stop to board on next cycle arriving
at board stop.
1. Cycle 1
2. Board Stop
3. Cycle 2
●
Board Received at Board Stop (1)
= Cycle Time 1 starts
●
Board Received at Board Stop (2)
= Cycle Time 1 stops and Cycle Time 2
starts
Squeegee Pressure
DEK printers utilise a pressure monitoring and feedback system, which ensures that the pressure
applied to the squeegees is the same as that which is programmed. However, if different length
squeegees are fitted or the material hardness changes it may take one or two prints for the pres-
sure to re-stabilize.
Benchmark test using QC-CALC
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106 Technical Training E by DEK 12/2017
Set up machine for benchmark test
Load the 265test1 product file and ensure that the following parameters are set correctly:
Note: Calibration stencil, Calibration board and SPC Benchmark board are NOT supplied. They
need to be ordered separately.
Front Print speed 25 mm/s
Rear Print speed 25 mm/s
Front Pressure 5kg
Rear Pressure 5kg
Separation Speed 1 mm/s
Under Clearance 20mm
No paste dispense or Screen Cleaner rate
SPC Configuration:
●
Data output rate = Every cycle
●
Start Rate = 1
●
Sample Rate = 0
●
Start Rate Limit = 0
●
SPC data mode = Disc
●
SPC Format = Windows
●
Update On Start = No
●
Align Inspect mode = Post
Ensure that the following hardware is set-up correctly:
●
9 Tooling support pillars are used
●
Squeegees fitted are of the correct length to suit board and heights calibrated
●
DEK alignment test board (Part Number 137071) is used
●
Screen loaded is the calibration/dry align screen
Adjust machine parameters for benchmark test
●
Transport Mode Left to Left (or Right to Right)
●
Upline Protocol No FMI
●
Downline Protocol No FMI
●
Screen size 265