Estimating ink usage for production inkjet presses

Posted at 12:33 pm on 12/15/2016
Estimating ink usage for production inkjet presses – What, no job file? 
Ink is the single largest variable cost for production inkjet presses. What’s the estimator to do when the estimate request has no job file? 
The cost figures shown in Fig. 1 below are generated from estimates to manufacture 500 each of 11 books on a roll fed inkjet production press with finishing to collated book blocks. In this example, ink is ~ 22% of costs. 

Fig. 1 Estimated costs for manufacturing 500 each of 11 books on a production inkjet press & finishing  platform. Direct press costs are comprised of the lease payments for production inkjet press and digital finishing platform.

As you would expect, ink usage is determined by the job content and then by the number of drops required to print that content. In this case, the ink usage difference between a book with the lightest vs. the heaviest ink usage is ~ 9x. With this range of ink usage, multiplied by the cost of a barrel of ink, you can see that running a profitable inkjet press compels printers & converters to learn to use the tools and processes to estimate and reconcile ink consumption. 
It’s helpful then, that press vendors provide tools for ink usage estimation and reporting. For estimation, the process involves running the job file through a software program. Ideally, the vendor also provides a post-production tool to report actual ink usage after jobs have run. This report allows the estimator to reconcile estimated vs. actual costs. 
The post-production reporting tool should also account for ink waste – that’s ink consumed during start-up and shutdown, and for jetting module maintenance functions. Press running conditions impact the ink waste factor. For example, a press used for proofing, with a lot of idle time and a daily shut-down cycle, will typically report a higher ink waste factor than a busy production press with less idle time and fewer shutdown cycles. Press running conditions determine your ink waste factor. You won’t know what it is unless you pull reports and work the data. Ink waste adds up and it should be accounted for in the job costing calculations. 
For estimation, one sticking point might be that the customer’s job file is not received together with the request for estimate. In the plain language spoken by an inkjet press owner: “Pigs will fly when our estimators are supplied with job files together with the estimate request. It never happens.” In other words, ink estimation tools have a limited function when there’s no job file in-hand. 
Consider this scenario. Your prospective customer is shopping the job around to 2 or 3 printing companies. The horror! Each company has the same problem – how to generate a precision estimate when there’s no file in-hand. 
Here’s a work-around to consider. If it was accepted by all 3 companies, then, when it comes to ink estimation (without a job file) the prospective customer would hear the same common sense guidance from printers with production inkjet presses. 

To accommodate the customer’s requirement for an estimate prior to submitting the final production file, the estimator will use best judgment for ink usage based upon visual inspection of the available art and print specifications.
Advise the customer that a reconciliation estimate will be provided upon receipt of the final job file. Adjustments to the estimate for ink cost (up or down) are submitted for the customer’s approval prior to running the job. This reconciliation step follows old school Trade Customs of the Printing Industry of North America, especially No. 5: 
ACCURACY OF SPECIFICATIONS: Quotations are based on the accuracy of the specifications provided. The provider can re-quote a job at time of submission if copy, (data) or other input materials don’t conform to the information on which the original quotation was based. 
Employing an ink reconciliation step in the estimating process offers protection for both the customer and the provider (press owner). This practice would put competitor companies on the same footing vis-à-vis the customer. 
This suggested work-around takes the position that the end-user customer must be made aware of the printer’s requirements for delivering estimates. It attempts to balance the customer’s need for an estimate with the printer’s need to accurately estimate ink costs to produce the job. 
Even better, encourage customers to pursue training and education to optimize the design for inkjet. This is a whole different subject. It’s most recently presented in The Designer’s Guide to Inkjet, (from Canon Solutions America) by Elizabeth Gooding and Mary Schilling. 
When a process is set-up and followed to estimate and report on ink usage, over time the estimator will become familiar with what to expect. Here are a few steps estimators can deploy internally to control ink costs: 
• Generate reports for actual ink usage (from the press) and compare to ink sold for the period. 
• Maintain a database to track ink usage by job and customer. This can be useful to inform future estimates for pickup jobs and jobs with similar specs. 
Every printing organization plays within the confines of its customer relationships. Educational book manufacturers deal with multi-year contracts. Direct mail printers and label converters might be job shops where every job requires an estimate. The bottom line is – control ink costs. You must know what your files look like. Adapting old school trade customs, where the customer is advised upfront that the estimate will be revised upon receipt of the final production file – might prove to be a useful work-around when there’s no file submitted with the job estimate. This step protects customers and press owners alike. It might even put competitors on the same page when it comes to estimating ink costs. 
Paul Dombrowski is an independent ROI Analyst for digital print systems. Paul works with printing organizations to help calculate the costs and benefits of new digital presses. Paul can be reached at (312) 401-7464, 
This brief was published in Graphics Journal, December 2016, by Printing Industries of America, Great Lakes Graphics Association

Total Views: 1524