What is the cost of ink? Understanding the Costs of Pad Printing
There probably isn’t a day that goes by that we don’t get this question. In this post, we will answer the ultimate question, “What does it cost to do pad printing?” We will show why our TTN pad printers are the absolute best choices for maximizing output while helping you understand the importance of efficiency in pad printing. So, sit back and relax while we help you see the true costs of pad printing by first studying ink prices.
One of the issues many people dwell on before taking the leap into pad printing is the cost of ink. Many get hung up on these prices. This is a non-issue on a per-part basis, especially when compared to other forms of placing messages on parts using other methods, like stickers.
The difficulty in trying to isolate the ink costs for a pad printed part is that there are many variables affecting the prices. Image size, ink cup size, multiple colors, and substrate type all influence this number. Some image sizes are very large. For example, the Universal 200 can mark a 3-inch by 7-inch image using a closed ink cup format. This uses far more ink than using the manual HP120 that marks a maximum image size of around 2 inches in diameter. Simply stated, placing more expensive ink with a larger mark will cost more than using a lower priced ink for a smaller image.
Furthermore, ink colors and types affect the hardener and thinner required, which also affect the price of the ink. Smaller ink cups contain smaller amounts of ink, but they also use smaller amounts of ink due to the maximum image size. Generally speaking, machines including our TTN HP Manual Series, our TTN Universal series, and our TTN Professional Series, all have ink cups that allow a setup to run for approximately a full 8-hour shift. This allows users to setup the ink cup once and run parts until a shift is over. This aligns perfectly with most two-component inks (such as ink with hardener) which have a gel time that is approximately 8-hours. Two component inks start to solidify at the 8-hour mark, so cleanup at that point is required.
With this said, one can make some assumptions and some averaging to gain an approximate understanding on what these ink costs are for each part you need printed.
It’s important to accept that most of the time companies end up throwing away more ink than anticipated, as experience has shown us that most people mix the ink for the job, print the job, and then throw the rest of the remaining ink away.
Most of our TTN machines, including the Universal series, can use different size ink cups which helps lower setup costs and reduces the amount of ink left at the end of a job.
Our TTN Universal 90 series ink cup can contain approx. 50 grams of ink. Assuming hardener is also required at 10% and thinner at around 15%, we can then start to do some math to show what the true ink costs will be.
Some further assumptions and averages need to be done, as well. Ink costs today range from $70 to $130 per kilogram for most standard pad printing inks (1 kg = 1000 grams). Hardeners range from $30 to $70 for approximately 200 grams and thinner is around $30-$50 per liter. Our average ink price for this exercise will be $100, our average hardener price will be $50 per 200 grams, and our average thinner price will be $40/liter. We will also need to assume 1 gram of thinner equals 1 milliliter.
So, let’s assume we fill our ink cup with 50 grams of ink, 5 grams (10%) of hardener, and 7.5 grams (15%) of thinner.
Doing the math, we need 50 grams of ink ($100/1000 grams=$0.10 per gram), 5 grams of hardener ($50/200 grams=$0.25 per gram), and 7.5 grams of thinner ($40/1000 grams = $0.04 per gram).
To set up our ink cup, the math looks like this:
50 grams of ink @ $0.10 per gram = $5.00
5 grams of hardener @ $0.25 per gram = $1.25
7.5 grams of thinner @ $0.04 per gram = $0.30
To fill our ink cup with 62.5 grams of product (ink, thinner, and hardener) will cost $6.55.
This allows the machine to run all day using the Universal 90’s ninety-millimeter ink cup, putting an average size 2.5-inch image on the part. Remember, most of the time pad printer operators end up throwing away ink after each job, as it is simply not used.
The next assumption that has to be made in our model is the output of the machine with the operator. In our many years of experience we have seen most pad printing operators print between 500 to 700 parts per hour. There are always variations as very complex-shaped items can severely limit this number, while other operators can operate at a very high output, even exceeding 800 prints. Even though the average is around 600 parts per hour, let’s just assume our new operator is operating at this lower limit of 600 parts per hour.
In an 8-hour shift an operator should be able to print approximately 4,000 parts with a couple breaks. Assuming the ink cost of $6.55 we can now divide by the 4,000 parts to find what the ink costs are over that timeframe:
$6.55/4,000 parts = $0.001637 per part
This means the ink cost is nearly 1/10th of a penny for each image printed. Now, if we go back to the first paragraph where we compare this to stickers, we can clearly see stickers have higher materials cost versus pad printing ink.
However, we also need to take into account the machinery cost, labor, and other items. We will tackle that in further posts. For now, it is important to realize that one of the biggest differentiators in this is the overall output. A person placing stickers accurately on a part versus a fixtured pad printing mark will be dramatically different labor equation. When accuracy of image placement is also taken into consideration a beautiful pad printed mark can be centered and look far more professional taking a fraction of the time stickers can be placed.
Therefore, pad printing is a great solution – versus manual sticker placement – including tagless printing of t-shirts, in not only total volume of output but also overall cost savings.
Consumables Costs (Other Than Ink)
Pad, plates, rings, and fixtures are all items that wear, or have item-specific uses. These all need to be accounted for in the cost-per-part calculations to print images. For this illustration we are going to assume a 50,000-part production. Many times, production runs may be limited to only several dozen, so items like clichés (the printing plates) and fixtures (the item’s holder) will need to be more temporary and affect costs. For higher volume applications, one consideration would be to have a longer lasting thick steel cliché, which can last over a million prints, and using higher quality metal fixtures (rather than silicone).
Starting with pads, we need to make some assumptions. We know that printing on t-shirts will allow the pad to last hundreds of thousands of prints. The opposite is true for printing on items with sharp edges or complex shapes. This is very debatable as the averages differs greatly depending on the part printed. Many of our customers seem to go through a pad every 50,000 parts. The average pad today costs around $75, which means the per part price is $75/50,000 prints = $0.0015 per print.
As with other items in this illustration, plate costs need to be averaged. For this exercise we will use a water wash plate, purchased directly from us. The size of the average one-color plate is approximately 100×225 mm. The Universal 90 uses one slightly larger, because it can also easily print larger formats. Our TTN HP90 and Professional one-color machine uses one slightly smaller. At the time of this writing plates cost about $75 to make a plate with film (or a laser plate).
Assuming operators only place one image on the plate and that the plate is used to its entire lifespan (which is about 50,000 prints), we can then derive the following per-print cost from the plate:
$75/50,000 prints = $0.0015
However, did you know all our TTN machines allow at least two images to be placed on each plate, reducing the per-image price by 50%? Additionally, our TTN YL50 aluminum laser plates can contain up to four images per plate. This allows the above number to be halved or even quartered depending on those variables. But, for simplicity, we are only going to place one image per plate.
To lower the plate price further, many companies decide to take plate production in-house where they can create multiple images on each plate, driving the per-image price from our illustration of $75 down to just a few dollars, as they batch process them in equipment they would have to purchase and learn to operate. For more information on this, please contact us today.
Fixture costs can vary widely. A two-kilogram container of our knead silicone putty (to make fixtures) can make fixtures that last 10,000 to 20,000 prints. On the other end of the spectrum is a complicated milled metal fixture which can run thousands of dollars. Today we supply many of these fixtures in the market at around $500 each which use a combination of metal, integrated magnets, and POM (a plastic which ink has difficulty to adhere to). Assuming we have a $500 fixture cost for our 50,000-print job, we see the fixture cost is $500/50,000 = $0.01 per part.
Rings are also items that wear. Most rings can go hundreds of thousands of prints without any issues. For argument’s sake let’s say that a ring is broken twice a year in a high output facility. At an average price of $350 for a ring that is $700 for ring costs per year:
$700/12 months = $58.33/50,000 prints (Remember we are printing 50,000 parts in one month) = $0.001167 per part
Total consumables cost for our 50,000-print job is calculated as follows:
Plate – $0.0015
Pad – $0.0015
Fixture – $0.01
Ring – $0.001167
Total consumables (not including ink) costs for 50,000 parts in one month is $0.014167 per part.
Wages, Machinery, and Other Pad Printing Costs
For our calculations 50,000 parts will require 100 working hours to complete. Again, this is a conservative figure and can vary. If operating output is increased by 20% to 720 parts per hour, then a 20% reduction in hours to complete the part are also accomplished. Calculating local hourly wages will follow this simple formula:
wage x hours = total hourly wage
Let’s assume an $18 hourly rate (plus benefits, which may place this closer to $25/hr) x 100 working hours = $2,500 for 50,000 parts or about $2,500/50,000 = $0.05 per part.
So far this is the largest factor in pad printing costs, and we can see output is the key to lowering overall pad printing costs.
Machines in the USA are a capital expense and can be depreciated once they are placed into production. We suggest asking a tax expert on the benefits of capital equipment cost deductions and Section 179 machine expenditures. Further information can be found on the IRS website here.
Other ancillary equipment that will be required for pad printing is an air compressor (if pneumatic), corona treatment machinery, and even possibly drying racks or an oven depending on the substrate. These should be considered when deciding which machinery to purchase and how much to charge per print.
Electricity costs to run the machinery and the air compressor need to be taken into account, as well. A 240v 22-amp 80-gallon large air compressor will run a few minutes every hour. This equates to (240v x 22 amps = 5,280 watts). Assuming this compressor starts every 100 cycles for 3 minutes means it runs 6 times in an hour at 3 minutes each time. This equates to 18 minutes of run time per hour. For an 8-hour shift that equates to 144 minutes of run time or about 2.5 hours:
2.5 hours x 5,280 watts = 13,200-watt hours/1,000 = 13.2 kw/hr
Austin, Texas charges approx. $0.14 cents per kw/h, so that means it costs about $1.85 to print our 4,000 parts for the day, or $23.13 for our entire 50,000-part job. This comes out to $0.000463 per part.
A pad printer will use even less energy at about 1.5 kw/hr. We can see these are negligible in the factor of our illustration on a per part basis.
Packaging, Pre-Treatment, and Other Costs
In addition to the costs outlined above, one must consider labor for packaging, any scrap items printed, and shipping costs to get the products to the customer. These are all added to the final part cost to pad print. These last few items can drive the price-per-marked-part up as output is affected. For example, if you print 50,000 parts in a 10-day period of time, but it takes a day or two to pack, the prices start to be affected by paying workers to package the items.
We have seen companies that also need to consider printing on special surfaces, such as glassware, which means preparing the glass surface with a torch or Pyrosil to treat the surface. This adds time, which can also affect printing output and costs. Today pad printers can be built to avoid packaging and pre-treating by building it into the printing operation so it is done in-line with pick and place robots or having the treatment at the site of printing directly attached to the machine. These have larger upfront costs but lower overall per-print costs as the payback is shortened for high volume applications.
As you can see, there are many items to consider in the decision to pad print but if we take some averages, and try to isolate variables with these averages, we see final part images can really be just several pennies to put your image on a product. With the largest cost being labor, it is important to understand the implications in advance, and not focus on saving a few dollars on ink, pads, or rings, as these are inconsequential costs.
Best Ways to Increase Output and Decrease Costs
It is wise to focus on driving up efficiency and output by purchasing high quality, dependable machinery. Quick changeout times, fast setup times, and getting the printer to start printing are paramount. Many pad printers today will operate using rotary tables which lower per-unit prices down as labor is reduced and output is increased.
Our TTN line of machinery has the industry’s fastest setup times with registration done on the plate and not on the machine, saving up to 45 minutes of setup time per job, allowing an entire 6-color job to be setup in under 5 minutes, including the ink mixing.
Our TTN Servo Innovator line is a custom line of machines that allow up to 6 colors be printed at speeds up to 1,600 parts per hour, which is the fastest output in the industry. This, coupled with the fact that TTN has the ability to switch from a 6-color job to a 2-color job, switching pads, plates, ink cups, and fixtures all in under 5 minutes, means job switches happen fast, keeping dollars in your pocket.
Output has the greatest direct effect on per-unit price and should be focused on when deciding which machine to use and if add-ons like rotary tables, sorting/packaging equipment, pick-and-place robots, or other machinery should be used. For more information feel free to contact us to discuss how we can lower your overall operating costs.
What do you think? What would be the time and labor costs to accurately place stickers on 50,000 parts? Let us know in the comments below and thanks for reading!