Best die-cutting practice seminar by Bobst

With an aim to educate its customer, Bobst conducted a day-long seminar on best practices on die-cutting at the Hotel Waterstone in Andheri, Mumbai on 19 November 2015.

23 Nov 2015 | By Priya Raju

Titled ‘Best Die-Cutting Practices’, the seminar laid emphasis on the various die-cutting techniques and do’s and  don'ts of die-cutting in the interest of improved productivity of the die cutting machines for their customers.
 
The event commenced with Sameer Joshi, head - Bobst Services centre addressing the guest. Joshi said, “The event is aimed at educating our customers about the best practise in die-cutting and use the die-cutting tools efficiently.”
 
The key speaker of the event was Moreno Gidhini, head of Bobst SA competence center in Switzerland, shared the various guidelines for the die-making process and how one can increase the productivity and quality with these guidelines.
 
Gidhini shared guidelines right from the design stage wherein the design optimisation with layout was discussed. Also, the guidelines for die-cutting in terms of the importance of compensation, proper rubbering, nicks and do’s and don’ts for embossing dies plus the best practices to be followed in an organisation to improve the workflow and productivity.
 
Gidhini highlighted the importance of preventive maintenance in an organization to ensure smooth productivity and prevent the unforeseen breakdown of machines. Gidhini said, “To ensure smooth functioning, regular training for the operators is critical since they are responsible and ensure all the best practices are followed.”
 
To advocate the importance of training and to generate skilled workforce, Bobst conducts a ‘Machine operator training programme”. The course emphasises on practical learning and contains 75% shop related practical class. 
 

First guideline: Layout
Care should be taken when designing a layout of the carton.

Fibre grain direction is critical. Always go for long grain direction while designing the layout instead of the maximum number of ups. This plays an important role in machine speed.
 
Minimum flap dimension should be 5mm
 

The cutting force should be considered while designing. This can be calculated with a software.

Guidelines for die-cutting
The quality of plywood used to embed the metal dies or creasing rules is important. Birch wood type of plywood is recommended and should be of 11-13 layers

The laser cut, when done must be perpendicular to the substrate
 
The cutting and creasing rule die. The die should have rounded edge instead of sharp pointed edge.  Rounded edge deploys more pressure and creates sharp creases and cuts without burr.
 
The thin plates used in cutting die is of soft (one time, short runs), hard (80%of jobs uses this) and extra hard (long runs)
 
Lastly, one should have spare cutting and creasing rules, in case of emergency. This will ensure the productivity level is maintained

For embossing:
In an embossing die it is important to provide for compensation. (compensation/support to the area where there is no embossing die especially at the edge) is important. This can result in the increase in quality and productivity and reduces the make-ready time and increase the life.

The material used for patching should be 0.1mm thick paper. Butter paper is recommended. Also, do not use plastic material for patching

Best practise in an organisation for smooth production:
Preventive maintenance. Keep your machine clean at all times.

Substrate/cardboard conditioning is important to maintain the moisture level. It increases the quality of creasing.
 
The raw materials should be stacked properly. So pile conditioning is important. One can use a pile turner for this.
 
Separate equipment’s for operators must be given for each machine. Eg. Hammer, tape, screwdriver etc.
 
A proper job sheet should be maintained for individual jobs.
 
Proper storage area for tools is important. Eg. Store in place where there is no temperature fluctuation, use racks, prevent against humidity.
 
Finally, the regular training for the operators is critical. It is they who will ensure the above things are practised