1) Printing Four Foot Banners: ValueJET 1204 and PrismJET VJ48 users sometimes have questions about how to get the maximum 48” print width for production of four foot wide banners. The printer’s maximum print width varies depending on whether you’re printing unidirectionally or bidirectionally. During unidirectional printing, the print head only lays down ink while travelling from the capping station toward the opposite end of the platen: right to left if you’re facing the printer. During bidirectional printing, the print head lays down ink as it travels back toward the capping station. This is the preferred method because it is of course faster.
But during bidirectional printing, the printer/firmware/head needs some space to come to a full stop, change direction and begin firing the nozzles again. This requires that it have a little room to accelerate to print speed. The advancement from the Falcon Outdoor firmware to the ValueJET firmware reduces this speed up space from 2” to ¾” so the maximum print width in bidirectional mode is 47.24”. So you have two options. Print it more slowly, or print it just a little bit smaller.
Keep in mind that 48” media will still have to be hemmed and grommeted, so the finished width will only be 46” anyway. So if you print bidirectionally and get ink on 47.24” you have room for an unprinted, hem. In either case, make sure you adjust the default position of your graphic in the RIP software to create the unprinted border which will be the finished edge on the right side (facing the printer), or design your banner with a full bleed allowing for the finishing of that side of the media.
2) Preventing Head Strikes on Banner Material: Another common issue that seems to trouble banner users is head strikes caused by rippling banner media. The culprit here is excessive heat.
Unlike adhesive backed vinyl, banner media has no Kraft or silicone liner underneath it to absorb some of the heat from the PrismJET VJ’s integrated heaters. More of this heat travels all the way through to the PVC layer laminated to the face stock. As a result, temperatures that work fine for vinyl can cause banner media to ripple from overheating. This can cause head strikes, which will ruin your print, and, over time, may damage your print head. There are two ways to reduce head strikes on banner material.
First, adjust your heater settings to 35° and 38 ° respectively. Leave the dryer setting at 50°. (See Fig. 1)
Second, make sure your head height is set to high. (See Fig. 2) Really, for anything thicker than 6mil vinyl, I would run it with the head height in the higher position. This not only reduces the chance of head strikes, but optimizes the distance between the head and the media, which is part of the quality equation. Dramatically narrowing the gap between the piezo print head and the media will distort the dot placement and reduce image clarity. This may not be noticeable on most standard banner graphics, but it can make a difference if you’re trying to dial in a high resolution print.
3) Using Continuous Feed on Reverse-Wound Banner Media: The next issue people encounter when printing banners is dealing with continuous feed on reverse- wound media.
Reverse wound media is partly a leftover from the days of the dominance of the Oce Arizona, the most commonly installed solvent printer of the pre ecosolvent era. The Arizona’s media feed was designed to accept reverse-wound media, so much of the solvent print media was designed and sold accordingly. Today the Arizona is but a memory, but a new factor has taken its place. The mills producing solvent compatible banner scrim are designed to finish the roll with the print side in. In order to produce standard wound media, the mill has to coat it, roll it, then unwind and rewind it.
This extra step adds time and labor, so in a cost conscious market, the default configuration is still reverse wound. This is not an issue if you’re using double sided media, like our dandy new PrismJET 13oz blockout. But with standard banner media, it can be a problem with long runs. Here’s what you do. Load the roll as if you were going to feed it away from the printer platen, then pull out enough slack to feed it through the platen and begin printing. (See Fig. 3) Just remember to monitor the print process to make sure you’re not pulling directly off the roll. Pulling directly off the roll can cause wrinkles and head strikes as the tackiness and static cling of the PVC coating resist the media feed system.
4) Printing on 38" Media on a PrismJET Extra 38: A question came in this week from one of our PrismJET Extra 38 customers. (The PrismJET Extra 38 is essentially our version of the Mutoh Falcon Outdoor Junior). He was looking at the new PrismJET 10oz banner media, but lamenting the fact that the narrowest width for that product is 38”. Mutoh’s specifications for this printer define a maximum media width of 38”. But there’s a catch. The 2” at the far left of the platen is required for the print head to accelerate. So the printer won’t initialize if that area is covered. Fortunately, this is only an issue at media initialization, so, if you fool the printer into thinking you’re using 36” media, you can begin your job. There are two simple ways to do this.
- Black Vinyl Mask. If you cover the yellow zone with black vinyl, the media sensor will not sense the banner in this restricted zone and you can proceed. Remove the vinyl before you begin printing. If you have to lift the lid or turn the printer off during the print job, you’ll have to reapply the mask.
- Notch Your Banner. When you load the 38” banner media, cut a 2” notch in the far left corner. The printer will read it as 36” media. Before printing, simply advance the media to the full width and start your print job. Of course, you could simply use 36” media, but that may limit your choices and raise your cost.
These are all suggestions from our "top-notch" color tech support department. I hope you find them helpful.
