Optimize makeready with effetive way
Why cut/uncut areas come out?
One of the reasons for decreasing diecut productivity would be makeready to adjust cut balance.
Diecutters need to stop running to adjust balance which leads to low productivity and heavy burden to operators.
Many box-makers are struggling to improve and solve it.
*We think these are the reasons for that.
1. Machine accuracy Balance of diecutter
2. Dieboard precision Height of cutting blade(especially bending area), Balance of dieboard
The reason could come from both machine and dieboard.
We focus on shortening patchup processing and explain how to arrange makeready correctly.
Adjustment at dieboard side Various makeready tape
It is a standard way to adjust uncut areas with makeready tape.
Good for cardboard thickness 0.02～0.08mm
Cardboard jobs are more sensitive to patch up and we recommend to use thin makeready tape for that.
Good for corrugated board thickness 0.09～0.19mm
Blue tape, White tape, Brown tape
Makeready tapes of corrugated boards are thicker in general since press pressure is bigger.
We do not recommend these makeready tapes for cardboard jobs.
Important points of makeready tapes
It is natural to put makeready tape precisely for correct patch up.
Overlapping, crossing or out of positioning causes imbalance cuts in other areas.
Trick to save makeready time Machine pressure
Figure out machine pressure.
If you know where to makeready in advance, patch up would be faster.
This is standard flatbed dicutter pressure condition on average.
The pressure of gripper side and center area are weaker as you see.
Some latest models have functions to adjust this imbalance.
However, old flatbed diecutters do not have such a function and you need to take measures to adjust balance.
In reference to the top view of chase, you put makeready tape on the red circled area which has imbalance in advance. Then, you set up machine pressure and try it.
Standardizing first press pressure leads to 70-80% cut makeready condition which contributes to saving time.
*Each machine has a different pressure condition. It is important to understand machine freasures and try this adjustment in advance.
Trick to save makeready time Makeready tape
Patching up to uncut areas might be too thick. In this case, the balance affects well-cut areas, then it may become uncut. You need to put makeready tape both areas to avoid it as in the picture below.
In case of rounded areas, it is important not to overlap makeready tapes.
It needs to adjust balance to put makeready tapes on uncut areas.
In this way you can reduce machine downtime to decrease take out chase for makeready.
Adjustment of Machine side In case of machine imbalance
The reasons of machine imbalance are following,
1.First knife cut mark at the cutting plate and chase side
2.Machine pressure imbalance
As for 2, we recommend that box-makers shall ask machine companies to maintain adjustment of press pressure regularly. It would be 1-2 times a year, it is hard to do frequently.
In 1 case, it happens because of the first knife onto the cutting plate and chase.
All the diecutting has the first knife mark. Gripper side blade is the first knife as the picture below.
Adjustment of machine balance
1. Balancing sheet
You can adjust machine balance and approach from dieboard side like imbalance of blade bending, rubber/cork pressure and layout.
DAISO MAT is makeready time saver sheet based on our experience and technology as a diemaker.
Concept and principles of DAISO MAT
It is quite easy setting, you just put this DAISO MAT between dieboard and chase.
It consists of special stainless steel and resin film in total 0.5mm thickness.
It will absorb the overpressure of cutting blade to sink into it.
※With DAISO MAT, decrease machine pressure 0.5mm.
It is common to start makeready with 30-40% area cut condition in usual job.
If you arrange more pressure, cutting blade edge of cut area could be damaged.
Over-pressure would cause shorter-life dieboards and angle-hair, paper dust troubles.
DAISO MAT enables to reduce damage to cutting blade, thanks to absorbing over-pressure.
Under good condition flatbed diecutter, it takes 4-5 times of makeready (machine downtime) to check cut/uncut without DAISO MAT.
They tried DAISO MAT, then it took 2 times makeready only. It shortened the time significantly.
New dieboard makeready time shortened to 1/3.
In case of repeated dieboard, setup time is almost same, however, damage of cutting blade edge becomes less and dieboard lifetime is longer with DAISO MAT, we heard.
Adjustment of machine balance
2. Improvement of imbalance of machine dirt and rust
There are various dirts inside platen and chase.
Machine inside tends to be hot and humid. Oil/grease stain and rust etc. cause imbalance in many cases.
Platen cleaning is the way to reduce such an imbalance.
These pictures are the result of Platen cleaning.
There is terrible rust and dirt in the old machine which never takes platen cleaning.
After cleaning with special brushes and taking off rust and paper dust on the surface, it looks like new.
They told us that easier makeready and chase moves lightly and smoothly.
This cleaning service takes half a day. The regular cleaning keeps a diecutter good condition.
It would be essential for especially cosmetics, food and medical boxes which request high cleanliness and hygiene.
Improvement of makeready is always problem in diecutting process.
It would be hard to eliminate completely. It is the point to shorten machine downtime and take effective and time-saving makeready.
Considering appropriate usage of makeready tape and way of patchup, special items like DAISO MAT, and machine characteristics, hope you will improve makeready process which burdens operators.