If you’re printing on products like pens, golfs balls, phone cases, chapsticks, lighters and other dimensional items, jigs, and fixtures are key tools for high print quality. Here’s an overview of these devices and how they work.
1. What are jigs and fixtures?
Jigs and fixtures are sets of printing tools that are used to hold dimensional products in a fixed orientation for imprinting. They are often used in screen and pad printing but are an even more vital component when inkjet printing.
2. Why are jigs and fixtures necessary?
Technically, fixtures are needed in UV inkjet printing applications in order to create a (relatively) flush top surface for printing to reduce light reflection and ink mist. Operationally, they can also be helpful in speeding up production by templating layouts and product placement as well as minimizing reject prints.
UV curing in most inkjet applications is done via a lamp that is attached to the print carriage where the print heads are located. As the heads fire, the subsequent light cures the inks. When printing to 3D products, the depth between the product and the bed can cause light reflection.
In some cases, this reflected light can become directed toward the bottom of the print heads, prematurely curing the ink. This can lead to partially cured ink to underperform when it reaches the intended substrate – or even worse, the ink can become fully cured in the nozzle which would block it from firing. Losing nozzles will reduce the print quality and eventually require print head replacement.
Ink misting occurs when a ‘full-bleed’ image is printed onto 3D products, or when the “head gap” between the bottom of the print head and the substrate is too high. With full-bleed images, they are slightly larger than the object, creating an overspray or misting effect of ink that is jetted off the edge. This mist can create a variety of concerns that can lead to poor image quality, increased rejection rates and a shortened lifespan for print heads.
Similarly, with the head-gap being too high, the ink is unable to reach its intended target and creates a misting effect which can lead to blurry images ruining prints or ink pooling on the bottom of the print heads.
Ink pooling can result in scuffing and ink drops on substrates as seen in the image to the below.
( Image Depicts Ink Scuffing )
3. What attributes make a good jig and fixture?
A proper jig will have a flat-level surface that is equal to the apex of the product to be imprinted. Generally, there are two main categories of jigs or fixtures; one being a mask style and the other being a pocket style.
In the instances where there is a convex surface to be printed on, a masking fixture can be used to expose a slightly larger imprint surface. Golf ball printing is a good instance for using a masking fixture, while container lids or cell phone cases are good examples of products that would use a pocket-style jig.
With current LED UV lamps, the materials available for use in fixtures have greatly expanded as compared with ones required to hold up under metal halide or mercury lamps. Acrylic, Sintra/Komatex as well as Dibond have proven to be accurate and durable materials that do not add a significant amount of weight to the printer beds. Be sure to factor in both the weight of the fixture and a full load of product and refer to the maximum weight rating from the manufacturer.
Material finish can mean the difference between a great fixture and one that simply exacerbates the problem of light reflection. Matte black finishes are then ideal, as they will minimize reflection by absorbing light.
With the jig style and material identified, a few other items will ensure you have an ideal fixture for your workflow. Loading and unloading product quickly and efficiently is essential, so factoring in a through a hole at the base of a pocket to push items out or a finger hole beside the product to grasp it can be highly beneficial.
4. What are the advantages of using jigs and fixtures?
The proper use of jigs and fixtures will undoubtedly maintain the highest level of production uptime and will help maintain maximum print quality. By reducing overspray and misting, the instances of head cleanings soaks and manual wiping is substantially reduced. Additionally, operators are able to limit the downtime between bed loads by quickly loading or resetting a fixture with new products.
Jigs allow an operator to unload printed products and reload the fixture while the printer is running. This ensures that the print cycle time is the bottleneck of the production workflow, increasing the process workflow to its maximum efficiency.
5. How to get my own jigs or fixtures?
For our customers with cutting equipment, we often work with them so they can create their own jigs and fixtures with an overview of the goal, available material and the precision measurements of the bed.
Some shops are not equipped with lasers, routers or other precision cutting equipment and subsequently, send out for their fixtures to a local shop with the necessary equipment.There are
There are many companies that can help with fixture making in the UV Inkjet markets. Below are some that our customers have used in past:
- Digital Blanks has been a pioneer in this market since the inception of the tabletop and small format UV markets emerged around 2010. With offices in both the US and UK, they satisfy a large number of customer needs including custom jig manufacturing as well as stocking off-the-shelf fixtures and promotional products ready for UV Inkjet decoration.
- Inkjet Jigs is another source for standard pocket and mask jigs. They are very experienced with the Mimaki bed formats and can assist with both design and fabrication.
- RB Fabrications has been catering to the awards and recognition industry servicing over 400 Retail and Wholesale Award and Trophy Shops worldwide for more than 30 years. As UV inkjet printing has increased in this market so have the services, which includes fixture making.
- Clear Image has been a manufacturer and cutting acrylics and other materials for over 30 years and boasts one of the fastest laser cutters in the southwest.
In more advanced instances where products need to be stretched, angled or otherwise manipulated to present the ideal angle for imprinting, the team at ITNH will work with various resources to spec, prototype and produce fixtures for our customers.
Whatever your production workflow needs may be, taking some time to ensure that you have the proper tooling to accompany your UV inkjet printer will make for a much more efficient process and can significantly reduce maintenance and downtime. For additional information, contact us at any time.