Clarke Joe, Lynch Colleen C. M&R Professional Screen Printing Series
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portion of the exposure light. Lower density and sufficient
light may pass and prevent development of the coating.
Further the clear part of the films should be reasonably clear
and allow sufficient light to pass unobstructed. The positives
must have adequate resolution and dimensional stability.
9. Select test squeegee blade.
a. Standard angle and pressure.
b. Length, width, height.
c. Edge to suit mesh.
The parameters of the blade are covered in precise detail in
chapter six. You should establish a squeegee angle and pres-
sure as standard and select a length, width and height to sup-
port your frame, tension and off contact. The edge of the
blade should be dressed with a radius to fit the mesh. This
technique increases shear rate on the ink while it reduces the
risk of pressure on the platen see chapter three.
10. Set squeegee blade.
a. Minimum deflection.
b. Uniform and total ink transfer.
c. Zero image stretch.
Once you have chosen the blade to fit your parameters, you
will be tasked to set it properly. Refer to Chapter Six (Press
Cal) for details. There should be no primary deflection and as
little as possible secondary deflection. The blade should pro-
vide uniform pressure across the screen mesh at all points and
should totally transfer the ink without hang-up or screen lag.
There should be zero stretch of the mesh in the stroke direc-
tion.
11. Maximize press speed.
a. Minimum dwell.
b. Fast blade speed.
c. Minimum stroke length.
It is obvious that your goal should be to run as fast as possible
and now is the time. The constraint should be your operators
until either they are trained or you invest in a Passport system
from M&R to automate unloading. Run sufficient air to the
The tolerance of the image is
the range acceptable size of the
original and repeated image.
Accuracy is always an issue but is
the only issue for the output films.
If they align at the point of expo-
sure they are satisfactory. Do not
assume that just because they
were computer output, they are
accurate. Things like roll ends
shrinkage and improper sizing can
cost you a fortune if it gets to
press. If the job is process color,
the registration can be calculated
from the dimensions of the pri-
mary rosette. The screen (Refer to
Chapter Two) is often a cause of
misalignment on press. The con-
struction and finishing of the fab-
ric are crucial to press register.
Once you get the fabric we sug-
gest that higher is not necessarily
better but proper tension, to sup-
port the off-contact distance is
paramount. The frames should be
flat or even if you get the job in
register, it is likely to go out very
quickly. Squeegee settings have a
serious impact on the register and
are covered in near completed
detail in chapter four. Just as press
calibration is a key factor for suc-
cessful close tolerance printing.
The garment and some more than
others are prone to shrinkage. If
so, the distortion will be against
the courses or left to right on a
standard jersey knit tee shirt. If it
is a Gauntlet or Challenger press,
the registration of the press is
most often the least of your wor-
ries.
Costing
Image T
Image T
olerance
olerance
PAGE
66
. 32
press, set a minimum dwell time with a fast blade
speed and a minimum stroke length. (See Chapter
Four on Press Cal)
12. Calibrate flash.
a. Accommodate press speed.
b. Minimum temperature.
c. Minimum distance.
After the press is calibrated and set to run fast you
can calibrate the flash units. Their first responsibility
is to accommodate press productivity and with the
right ink (later) and preceding conditions, this is pos-
sible. You will want a minimum temperature and a
panel distance as close as possible and a tube distance
at 2.25-inches. Chapter Five explains the flash oppor-
tunities available from M&R.
13. Optimize dryer.
a. Adequate for press output.
b. Below ink remelt temperature.
c. Energy efficiency.
A review of Chapter Three on inks will offer additional insight to dryer settings
and constraints. The dryer should be set to accommodate press output, below ink
remelt temperature of the plastisol and to run
energy efficiently. Do not confuse a test for
dryer parameters and curing parameters. The
dryer is one critical aspect to high speed, con-
sistent and complete curing but it is a singular
element. Testing for your dryer, dye sublima-
tion and migration, and degrees of cure are
covered in Chapter Three.
14. Select ink by properties.
a. Optical.
b. Rheological.
c. Thermal.
d. Physical.
Chapter Three lists the four properties and
details on each. Certain of these traits may be
Chapter 6
Figure 7.33 Part of maximizing
your press speed is to allow the opera-
tor the safety net of the Shirt
Detector. Even a seasoned operator
will miss a platen once in a while and
it causes an interruption of their
cadence. With most operators their
timing is impaired and they won't run
as fast out of fear of doing it again.
With the shirt detector everyone can
cycle at top speeds and allow the sen-
sor to automatically not print any
platen that gets missed.
Figure 6.34 This shows the in-feed of a
Sprint Dryer. The retention time and tempera-
ture should be calibrated for your printing con-
ditions (refer to Chapter). It is particularly
important when the garments have been flashed,
that you include this preheat in your calibration.
The Sprint will allow you to run virtually any
combinations of light and dark garments but it
should first be calibrated. HiRes AccuColor
Ó
garments compliments of Target Graphics.
PAGE
66
. 33
deemed mutually exclusive, that to get more of one property
requires that you get less of another. To negotiate in good
faith means that if there is real world value that you are willing
to pay for it. Most of your complaints about ink (and many
other elements of the process) can be dealt with by premium
quality materials and processing. One of the ink manufactur-
ers goals is to keep the price down; perhaps they have gone
too far?
15. Request a CofA.
a. Identify status quo.
b. Communicate to ink maker.
c. Anticipate improvement.
A Certificate of Analysis is similar to an internal QC (quality
control) sheet and is offered to large volume users of plastisols
worldwide. It identifies the properties of the ink specific to
that batch so the informed user can adjust or adapt to the vari-
ance in the product. No one makes perfectly consistent prod-
uct, there are normal and special variances. Normal variances
do not appear consequential to the ink maker but may have an
impact on the press. Special variances indicate anomalies or
extreme inconsistencies in the batch and may be good or bad
on press, but most assuredly they will be noticed. A CofA is a
warning of variance or confirmation that whatever variance
should not be noticed. This insurance policy will allow you
to communicate effectively with your ink provider in terms
that both of you can understand. From this communication,
you may anticipate improvement in the product.
16. Temporarily adjust to accept ink deficien-
cies, and repeat the folowing steps:
a. #10
b. #11
c. #12
d. #13.
If the ink does not suit your conditions (and a general purpose
ink will rarely do so) you will have to make adjustments. We
encourage you to look at these as temporary adjustments. It
may not be wise to compromise your press and prepress con-
Suppose you are trying to com-
pete with the printer in town who
has an automatic and you have
only a manual press. If you have
tried to outbid them, you have
either lost the bid or probably lost
your profit. The logic is simple;
the key is your opponents ability
to distribute fixed costs, some
refer to this as economies of
scale.
For example you have fixed costs
or general and administrative,
rent, phones, utilities and so on
for a monthly overhead total of
$24,275. The competition also has
fixed costs at an arbitrary fifty
percent higher than yours or
$36,400 per month. Four persons
in his plant can produce a nomi-
nal 400 pieces an hour of four-
color work or 3200 pieces per
shift. His cost is $36,400 divided
by his straight time of 173 hours
per month or 52¢ per print.
You run the same job with your
lower overhead and straight time
but your manual produces seven
dozen per hour or 84 pieces. Your
lower overhead still has the cost
of each shirt at $1.67 each. It is
impossible for you to compete.
For those of you with both a
manual and an automatic on the
shop floor bear this in mind. You
should parallel the images from
your automatic press on the man-
ual. Keep it for samples and strike
offs and do not prevent your
automatic from printing approved,
bill-paying work.
Costing
Y
Y
ou Cant Ge
ou Cant Ge
t
t
There F
There F
r
r
om Here
om Here
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. 34
ditions for inequities in the ink. Adapt by adjusting the blade
as described in Chapter Four. The ink may cause you to
restrain your Gauntlet or Challenger and full details are cov-
ered in Chapter Three on inks and Chapter Four on press cali-
bration. Flash details are covered in Chapter Five and will help
you deal with troublesome inks. Finally, you will need to adjust
your dryer, look to Chapter Three on inks for details on dryer
settings.
17. Provide proper labor.
a. Quantity.
b. Skill sets.
c. Orchestration.
The race is profitability and your M&R press is the racecar,
dont skimp on the labor to save money, it doesnt work that
way. Sufficient labor with the skill sets needed is the best
approach. You may want to join us in Chicago for our ongoing
training sessions. All attendees receive certification of curse
completion. The course helps the novice become familiar with
the press operation and printing fundamentals. Even the sea-
soned veteran will gain insight into this ever-changing industry.
Finally the labor must be orchestrated to focus on the goals or
production.
18. Assess costs, price accordingly.
a. Conversion costs.
b. Raw material costs.
c. Fixed costs.
It appears one individual made a price sheet and then everyone
copied it. Considering the diversity and individuality of each
shop, it is unlikely that any two-price sheets would be similar,
yet so many of them are identicalgo figure. Your conversion
costs have the greatest impact on your bottom line. Raw mate-
rial costs are easier to watch, but are not as significant. Keep
your fixed costs under control and you will be better prepared
to sustain profitability in the slow months. Once costs are in
check, set a price based on profit or revenues, not volume, and
you will be pleasantly surprised at year-end.
It may appear to you that we were
asking more of the ink manufac-
turer than of the other players.
That is not the case, it is simply a
matter of saying The last one to
leave, turn out the lights. In the
sequence of the operation pre-
press has the correct name it
comes before the production. At
this time we make decisions on
the nature of the detail and aes-
thetics of the image. These
include film generation, screen
mesh selection and processing,
stencil properties and processing.
The calibration of the press has
to be at a specification that will
hold tolerances demanded by the
art. It has to meet or exceed speci-
fications set by our banker and
creditorsspeed and reduction of
downtime.
Once we have met these criteria
and are ready to go into produc-
tion, just imagine if we put the
ink in and it looked the way we
want it to. One reason that this
doesnt happen enough is that the
ink maker is trying to hit a mov-
ing target; most of their cus-
tomers are not in calibration and
do not set up or manufacture to a
specification. The ink maker is in
the dark.
Once our customers have a
repeatable specification, the ink
manufacturers will be able to pro-
vide a product that pumps
through the mesh properly, flashes
dry and fast and that does not age
up or get too thin on press. It is
real world but only once we get in
spec and ask the ink providers to
comply.
Chapter 6
Wh
Wh
y The Ink Mak
y The Ink Mak
er?
er?
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66
. 35
19. Reevaluate ink
when ready.
a. Temporarily
adapt.
b. Repeat process.
Any changes that needed to
be made in the ink should be
welcomed because your sup-
plier has shown a willingness
to fit his product to your
process. Or you may be evalu-
ating a product from a differ-
ent source, either way, prior
to testing return your settings
to home position. Test the
product and make adaptations
of numbers 10, 11, 12 and 13
to accommodate the ink.
Interpret the results to see if
these accommodations are
preferable to the former inks.
The above nineteen points are
a map to successful produc-
tion management. They are
not the only path and may
need to be altered to fit your
particular needs. It is most
important that you have a for-
mal goal and a plan to pro-
mote that goal; we hope that
this map can help you to
develop your plan.
Percentage Downtime vs. Runtime
There are three facets to downtime: set-up, interruptive and changeover. Set-up
begins as soon as the operators begin to prepare the press for the next job.
Interruptive is the delays caused by the need to stop the press mid run.
Costing
Use the following steps to orchestrate production:
1. Calibrate the press.
2. Gauge image tolerance.
3. Establish off-contact distance.
4. Select screen mesh.
5. Support off contact with screen tension.
6. Select stencil.
7. Process the stencil.
8. Process films.
9. Select test squeegee blade.
10. Set squeegee blade.
11. Maximize press speed.
12. Calibrate flash.
13. Optimize dryer.
14. Select ink by properties.
15. Request a CofA on your inks.
16. Temporarily adjust for ink deficiencies.
17. Provide proper labor.
18. Assess costs, price accordingly.
19. Reevaluate ink when ready.
Orchestrating Production
How To
Instructions
PAGE
66
. 36
Changeover is the retooling work at the end of one job so that set-up can begin
on the next.
Obviously in this case, less is better, less downtime means more profit. So you
will want to know just how much of the day or press run that you are operational
and how much of it you are down. An easy way to gauge this fact is to calculate a
percentage of running time or percentage of downtime
As indicated in the table below, if you were to have one hour of downtime, set-
up, interruptive and changeover all totaled, and you printed a 30 dozen order at a
cycle rate of 30 dozen per hour, your run time as a percentage would be 50%.
Here is the trap if you speed up and run at not 30 dozen per hour but at 60
dozen per hour, twice as fast, your percentage of running time would drop from
50% to 33%. The con to having a high percentage of run time (or a low percent-
age of downtime) is to cycle slowly.
Run time, as a percentage is only relevant if it is attached to the cycle rate and
run length. To say that you have a really high percentage of run time could mean
you have long runs and you run very slowly. Is this something to boast about?
Chapter 6
Press Runtime As A Percentage
D.T.
min.
30
dz/hr
40
dz/hr
50
dz/hr
60
dz/hr
70
dz/hr
80
dz/hr
90
dz/hr
100
dz/hr
110
dz/hr
D.T.
hrs.
15
80%
75%
70%
66%
63%
60%
57%
54%
52%
.25
30
66%
60%
54%
50%
46%
42%
40%
37%
35%
.5
45
57%
50%
44%
40%
36%
33%
30%
28%
26%
.75
60
50%
42%
37%
33%
30%
27%
25%
23%
21%
1.0
75
44%
37%
32%
28%
25%
23%
21%
19%
17%
1.2
90
40%
33%
28%
25%
22%
20%
18%
16%
15%
1.5
105
36%
30%
25%
22%
19%
17%
16%
14%
13%
1.7
120
33%
27%
23%
20%
17%
15%
14%
13%
12%
2.0
135
30%
25%
21%
18%
16%
14%
12%
11%
10%
2.2
150
28%
23%
19%
16%
14%
13%
11%
10%
9%
2.5
165
26%
21%
17%
15%
13%
12%
10%
9%
9%
2.7
180
25%
20%
16%
14%
12%
11%
10%
9%
8%
3.0
Figure 6.35 The table above lists downtime in minutes in the far left column and hours in the far right column. Across
the top row is the cycle rate in dozen per hour. Below the cycle rate is the percentage of run time for a run length of 360
pieces or 30 dozen. The oddity is that the faster you go, the lower the percentage of run time at a fixed downtime. For exam-
ple at 50 dozen per hour and 30 total minutes of downtime, you are running 54 percent of the time. If you were to run
faster at 60 dozen per hour and have the same amount of downtime your run time would now be 50%. Dont worry; the
customer doesnt pay for percentages, run them as fast as you can.
PAGE
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. 37
Never use the percentage of downtime or running time as a
singular data point, it is completely irrelevant. You must know
what the cycle speed was and the total run length along with
the percentage of operational time.
Measuring Performance
A successful cycle rate must consider the PFDs (personnel
fatigue and delays); that is how do we keep the press running
at optimal rates for the long haul? Following is a list of steps
that you can take to maximize your cycle rate day-in and day-
out.
1. Always have a back up set of screens readied and out at the
press. It will cost no more to make the screens twenty-four
hours ahead of time. Your press should never have to wait
for a screen.
2. This is not the time to maintain the press (refer to the
M&R Operators Manual for details). Use our maintenance
schedule and do not maintain or clean during regular pro-
duction hours.
3. Have a spare set of squeegee and floodbar blades as a back
up clean and ready. The cost is truly insignificant and can
easily be paid for from the profit that this step will generate.
4. Rotate loader and unloader every 20 minutes. Loading is
physical and unloading requires focus, it is the first point of
quality control during production. Most shops that try this
experience a 10 percent to a 30 percent
5. Put a third person caddy on the press (refer to page 6.8)
This is the temporary assistant to the press team. The
caddy gets tape, Pellon®, moves flashes, adds ink to the
screens and most important speeds up each head as needed.
6. Rotate the third person caddy every four hours (refer to
page 6.8). Every four hours the caddy steps into the load /
unload loop. This system deals with personnel fatigue and
delays better than any we have seen. Plus the crew becomes
cross-trained painlessly.
If your total overhead is $36,400
per month and you work five days
a week, eight hours per day (173
hours per month), your cost per
hour of operation is $200.00. Lets
say that a job takes you fifteen
minutes to setup and forty-five
minutes to run on your only press,
for a total of one hour. The job is
475 pieces. Your cost per print is
42¢ per print. In other words, you
have a fiscal responsibility to gen-
erate $200.00 and with only one
press as your source of revenue,
the $200.00 per hour must come
from that press. So if you take an
hour to do anything it has a liabili-
ty of $200.00. Divide the $200.00
by the run length in pieces and
you have the per piece cost.
Your accountant may be shaking
his head but this take off of activ-
ity based cost accounting can
allow you to comfortably move
through the sea of negotiation
without any casualties or fatalities.
It is better too have a less precise
estimate of your costs than no
estimate at all.
This shorthand to cost estimating
will also allow you to compare
one job to the next as their value
is based on the time that they take
to get through the plant.
Costing
Time Is Mone
Time Is Mone
y!
y!
PAGE
66
. 38
7. Use the Shirt Detector at all times. This sensor allows even
a novice to run at top speeds without fear of that dreaded
sound of screen gluing itself to platen adhesive (refer to
page 6.38).
8. Optimize blade speed. When properly engineered most
work can run at near the top speeds of a Gauntlet and
Challenger. This manual will help with the print engineering
and refer to page 4.46 for details on blade speed.
9. Use Ink Traps (see page 3.17). Whether your run is long or
if you are flashing, End Caps hold the ink in place and
reduce the adverse affect of shear and heat from the flash.
10. Maintain proper air pressure and scfm at all times (as rec-
ommended in the M&R Operators Manual). To run proper-
ly, in time and at top speeds, you must provide chilled air
at the proper pressure and volume.
11. Have spare garments at press side prior to run. For some
reason this never seems to be an available supply of gar-
ments that can be used for scrap. Keep it in mind that the
shirt costs about $3.00. Our test site has one press for one
standard shift and $34,600 per month total overhead. His
applied cost is $3.33 per minute.
12. Set flash units as prescribed (refer to page 5.10). One
chapter is dedicated to this necessary evil. If your press is
calibrated and your flashes are then calibrated to it, flashed
production can nearly match non-flash rates.
13. Run high blade speed. The blade going just a little slower
can deteriorate your productivity (refer to figure 7.5).
14. Single stroke all colors. Double stroke is the assist to
improper print engineering but the enemy of productivity
(refer to page 6.5).
The dwell setting is a delay timer
that begins to count down as soon
as the print cycle is completed it is
not equal to the cycle rate of the
press. As soon as the print is
made and the platens drop until
the timer lapses the pre set time,
nothing will happen. However the
real time is affected by the dwell
setting as well as the speed of the
squeegee, indexer drop rate and
the scfm to the press. The press
will never move until the slowest
blade completes its stroke. So the
dwell timer wont start its count-
down until the blades are done
moving and this affects your cycle
rate.
To impress the boss, I will set the
dwell timer at an impressive
zero. But to not over tax
myself, I simply set the blades at a
slow speed. Now I have the dwell
time as well as the delay of the
slowest squeegee and I have the
document of speed but such is
not the case, it is not the reality.
Dwell settings, the slowest
squeegee speed, total colors of
the press, number of colors in use
at any one time, the timing of the
lift cylinders, the air supply and
the stroke length all affect the
production rate. Further as you
will find in this chapter, cycle
speed is relatively incidental on
short runs.
Chapter 6
Dw
Dw
ell
ell
Time
Time
Is No
Is No
t Enough
t Enough
PAGE
66
. 39
15. Do not be fooled by dwell time(see sidebar oposite page). Dwell time
can be very misleading and if you are referring to the setting on your press, it
has no bearing to real time.
If you want to know how fast you are really running you will need to time at least
one cycle. A cycle is the elapsed time (gauged by the second hand on your watch)
from an event until that event occurs again.
Costing
Effect of Dwell and Squeegee Speed On Flash
Dwell
Slow
Medium
Fast
1
56.7
65.5
65.9
3
49.3
53.8
54.1
5
41.9
42.1
42.4
7
34.4
34.6
34.8
9
27.0
27.1
27.2
Relationship Between Cycle Rate and Dozens Per Hour
Seconds
Dz. / Hr.
Seconds
Dz. / Hr.
Seconds
Dz. / Hr.
2.0
150.0
6.0
50.0
10.0
30.0
2.2
136.0
6.2
48.3
10.2
29.4
2.4
125.0
6.4
46.8
10.4
28.8
2.6
115.0
6.6
45.4
10.6
28.3
2.8
107.0
6.8
44.1
10.8
27.7
3.0
100.0
7.0
42.8
11.0
27.2
3.2
93.7
7.2
41.6
11.2
26.7
3.4
88.2
7.4
40.5
11.4
26.3
3.6
83.3
7.6
39.4
11.6
25.8
3.8
78.9
7.8
38.4
11.8
25.4
4.0
75.0
8.0
37.5
12.0
25.0
4.2
71.4
8.2
36.5
12.2
24.5
4.4
68.1
8.4
35.7
12.4
24.1
4.6
65.2
8.6
34.8
12.6
23.8
4.8
62.5
8.8
34.0
12.8
23.4
5.0
60.0
9.0
33.3
13.0
23.0
5.2
57.6
9.2
32.6
13.2
22.7
5.4
55.5
9.4
31.9
13.4
22.3
5.6
53.5
9.6
31.2
13.6
22.0
5.8
51.7
9.8
30.6
13.8
21.7
Figure 7.36 this table shows
the range of dwell time settings
based on a variance in the
squeegee speed. The table is in
seconds of dwell time per
squeegee setting. As you can
see, using dwell as a predictor
of dozens is futile.
Figure 7.37 This table shows the relationship between cycle rate in seconds and dozens per hour. After you time one cycle
in seconds as detailed in the paragraphs above, find the closest time (rounded to one even decimal place) on the table above.
Immediately to the right is the dozens per hour that you are running at that cycle rate. Refer to the sidebar on page 6.38 for
details on why not to use the setting on the dwell timer as the cycle rate in seconds.
PAGE
66
. 40
An easy way to time the cycle of a Gauntlet or Challenger is to start a stopwatch
as soon as the indexer begins to drop. Allow the watch to run during the print
stroke and stop the watch as soon as the indexer begins to drop again. This is the
time of one complete cycle.
The constant 300 allows you to convert seconds of cycle to dozens per hour, as
there are 12 of each in a dozen and 3600 seconds in an hour. 3600 divided by 12
equals 300. So divide 300 by the cycle time in seconds to determine the produc-
tion in dozens per hour or use the table below.
If you want higher precision in your dozen per hour rate, time ten cycles in sec-
onds and use the constant 3000. Divide 3000 by your seconds to complete ten
shirts and you will have dozens per hour.
Manual vs Automatic
This question is one of the reasons that we developed this resource manual.
There are very few cases that a manual press is a preferred choice over a Gauntlet
or Challenger press. There are typical exceptions of short run nylon jacket, base-
ball caps and such but for tee shirts and fleece automatic is the answer.
Your Gauntlet or Challenger press can be set up far faster but a good guideline in
the real world is five minutes per color. This is not register only (which takes sec-
onds with a Tri-Loc) but the total process. The guidelines for reaching and
exceeding this goal are published in this manual.
Chapter 6
Seconds Cycle Time And Productivity
30
50
70
90
110
345678910
Seconds Cycle Time
Dozens Per Hour
Figure 6.38 Once you time one
complete print cycle, you can divide
the constant 300 by those seconds
and arrive at productivity in dozens
per hour.