Printing area setup

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Can I use floor tiles as my printing platen instead?

Although heavy, floor tiles can be used as screen printing platen as it is also easy to manage.

Floor tiles do not have warping issues when subjected to liquid elements or to heat, however, it is costly.

The alternative material for floor tiles would be Marine Wood laminated with Stikwel adhesive (not Rubber Cement / “rugby”/ cement board adhesive).

If MDF Board is used, use sanding sealer as coating.

What is the proper setup on screen registration for multi-color prints?

1. Use a proper registration template to line-up multiple color screen prints, which is essentially a board with ruler guides on its X and Y axis.

2. Set-up allowances for inks to park (above the design) and use one artwork with registration marks already present to line-up the rest of the screens exactly where the registration mark is.

Is the size of the frame perpendicular to the size of the platens used for printing?

A frame that is bigger than the platen may fit as long as a screen mesh has been attached to it. The important factor that must always be considered is the size of the design and how it should fit within the section of the platen.

A big design with a corresponding screen frame size must be able to sit on a platen that will fit it for a comfortable and smooth printing.

A smaller design can sit on a bigger platen, but the artwork registration may be hit or miss, it is better to have all frame size in general dimensions.

When using a portable platen, it is important that your angle bar is longer than the width of your big frame to support your X-Axis (screw eye) registration.

How are inks chosen?

When choosing inks, find out the pros and cons of all inks. Consider the printability, the brilliancy, the hand-feel, the ease in curing, clean up, and the handling. Inks are either water-based or oil-based plastisol.

Choose Quality Inks. The ink consumption cost is a lot less over the cost of the substrate and the cost of production (i.e. electricity, manpower, etc).

Check ink compatibility against the substrate to be used. The Substrate can be cotton, sports jersey, spandex, towels, or synthetic substrate.

It is also best to consider client requirements.


General questions on the printing process.

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How much ink should be used?

It is better to put just the right amount of ink across and above the artwork of the screen, just enough to make a number of good prints without running dry. Placing too much ink on the screen prior to printing will cause the ink to go all-over the squeegee handle, making a mess.

Putting just enough ink on the screen makes returning the leftovers back into the container easier to scoop and manage.

What is the ideal multi-color print sequence?

When printing multi-color prints on light garments, you generally print from lightest shade to darkest shade or from smallest print area to the largest print area.

Proper sequencing with a correct printing process and using the right ink viscosity helps minimize ink build-up on multi-color printing (ie. smudging).

What is the ideal off-contact distance?

To achieve good printing output:

1. Ensure a high tension stretch mesh.

2. Set the screen to sit slightly (ideally 1/16” or 1/8” or a maximum of ¼”) off the shirt board.

3. Some machine presses have adjustments for this.

4. For manual presses, put a thin piece of cardboard or coins on the corners of the frame.

How many strokes/pass and coating is recommended?

Ideally, 3 strokes and 3 coats is acceptable on a good quality cotton substrate.

More strokes and coating may be advised if there are a lot of lint or excess threads visible through the print. Medium to hard pressure is advised on the last coating, otherwise, moisture may be trapped in the print during final curing.

The thicker the print coating, the glossier the print finish.

What will happen to the print if the strokes/pass and coating exceeds 3?

The more strokes applied to the print, the print output will have a darker shade.

The more coats applied to the print, the glossier and thicker the print output but it may also become less sharp.

What is the ideal printing technique for manual printing method?

1st coating, heavy pressure, 1-3 strokes, same direction, and semi-curing.

2nd coating, medium pressure, 1-3 strokes, same direction, and semi-curing.

3rd coating, medium pressure, 1-3 strokes, same direction, and semi-curing.

Lastly, subject to heat press machine, and heat conveyor.

What is the correct squeegee pressure to be used during printing?

For thicker inks:

Enforce just the right amount of squeegee pressure to get the ink through the screen.

An excessive amount of squeegee pressure can cause the ink to spread and smudge thereby creating a shadow or double-vision print, or uneven prints. In order to achieve a great print output, reduce the viscosity of the inks if it gets too thick.

On printing on dark substrate (i.e. shirts):

When printing on dark colored substrates with lower viscosity inks, do not apply excessive pressure. Excessive squeegee pressure for lower viscous inks will allow it to penetrate more through the substrate, making the print duller. Medium pressure is advised.

Technique is to apply first stroke with enough pressure, and the second strokes a lighter pressure.

Ensure to follow the correct (medium) speed and (60˚) squeegee angle, the correct squeegee, and other factors (soft-platen vs hard platen, mesh count, ink type, etc).

Is it possible to achieve high opacity with white base inks using 2 strokes and 1 coating?

On a lighter shade substrates, it is possible.

On a dark colored substrates, it is possible but it may be difficult. This is because your 1 coat, 2 strokes print output would depend on the quality of your substrate (100% comb cotton vs polyester cotton), the kind of inks that is being used, the mesh count, mesh tension, squeegee durometer, squeegee profile, print strokes, angle, pressure, and the pull / push technique.

Also, ink viscosity can affect the print opacity. The higher the ink viscosity, the higher its opacity. This is because the inks sit on the substrate surface only and has not fully penetrated into its thread weave.

Hence, setting a too high viscosity ink base can affect the washing fastness, in lieu of its surface hold only.

Is the wet-on-wet printing process possible for CMYK printing?

It is recommended that a wet-on-wet process be done for CMYK printing process as it allows the dots to blend well. This also speeds up the print production.

However, it is important to consider the following:

1. Do not put too much pressure when printing

2. When doing flooding technique, do it at a 70-80 degree angle without pressure

3. A long line table provides natural air flow to semi-cure the inks

However, if you are not accustomed to printing wet-on-wet, then it is better to do a dry-on-dry technique than incurring a damage print.

Is it possible to do a neon CMY print process?

YES, it is possible to work with a neon CMY process, especially if the design has some neon color requirements.

In printing Neon CMY process, the black color used is a regular kind (instead of the Process Black).

Is it possible to do a discharge print on CMYK process?

Discharge print works better on spot or solid print. Half tone printing is possible, for as long as it is not a CMYK process which requires dot blending.

How do I prevent ink build-up on the outlines of the artwork and having to clean it every "x" number of times (creating smudges on the screen)?

Avoid ¼” off-contact especially on a low tension stretched mesh. Build-up on an image edges at the back of the screen means there has been an occurrence of the screen image shifting. This means the mesh or the frame slightly moves back and forth on every print pass.

Some plastisol formulas can be more “tacky” than others, but high tack inks would also build-up elsewhere beyond just the edges of the images. A tight screen will allow you to flood stroke easily and this avoids ink build-up.

Is semi-curing in-between prints important? (Especially for plastisol inks)

Semi-curing via tunnel dryer/flash cure machine/heat gun results to surface drying only meaning the print underneath is still wet.

Curing at very high temperatures, especially on polyester garments will cause inks to collapse and will be highly prone to dye-migration.

Semi-curing the ink after every-print /coating before final curing will allow the print to stay in shape. It will have a sharp and clean image as opposed to a wet smudged print. On the other hand, an incomplete ink curing will create poor washability, color lost and cracking on your plastisol print.

How to print with high-dense ink?

To simplify a high dense printing, you need a high dense stencil.

A high dense stencil is expensive and the number of coatings will determine the thickness of the high dense print. A high dense stencil would require at least 3,000 wattages for the exposure unit to develop it.

Using a regular stencil to print high dense would require several strokes/pass with several coatings when printing to create more layers. This will not give a good high-dense stencil print.

For high-dense print output, use a hard square edge squeegee and a longer curing time with higher temperature setting.

Flash curing is faster than heat gun curing. Final curing is best done with a conveyor oven.

For heat press machines, do an off-contact curing, meaning do not lock in the press.

Is heat curing important for plastisol printing?

Plastisol inks do not dry up, unless it is exposed to heat. Heat gun curing or flash curing provides surface curing only. Hence, it is important to do final curing using heat press machine or a conveyor oven with its recommended temperature setting. Just watch out for the dye migration issues that may occur due to high temperature curing.

Plastisol prints that do not go through final curing will wash-off and cracks will occur when stretched.

How are inks handled/scooped out at the end of each stroke/pass?

1. Ideally, pull the squeegee all the way to the end of the frame and scoop the excess ink up with the squeegee and place it on the back (top) of the frame.

2. Lift up the squeegee when getting close to the end of the frame and lift up the excess ink, or stop when you pass the image area and lift the screen.

Or do a flood stroke to push the excess ink back to the back of the screen.

What causes the print to bleed?

Using a warped frame. Warp frames that are not properly tensioned can result in uneven tension across the screen mesh. This can lead to inconsistent ink deposition, causing variations in print quality and clarity.

A loose tension mesh. Uneven tension across the screen mesh can result in inconsistent ink transfer. Some areas may receive too much ink while others receive too little, leading to a smudgy print.

An over-pigment base. When an excessive amount of pigment is added beyond the recommended percentage load, it can lead to bleeding or color runs during the washing process.

A very low viscosity base. Inks with low viscosity tend to become more mobile and flow more freely on the printed substrate, often resulting in issues such as increased halftone dot size, which can lead to a loss of sharpness in the image and producing a smudged print.

Too many strokes with heavy print. Excessive pressure can cause the ink to be forced out from under the screen mesh, leading to ink squeezing beyond the intended boundaries and causing smudging or spreading of the design.

Wrong angle, speed, and pressure. These factors play a big role on ink penetration through the mesh. A slow speed and heavy pressure could potentially result in bleeding or blurring of the printed image, especially on porous materials.

How can ink consumption be computed?

On average, a spot print for an A4 size design can consume 10-15 grams per color. For halftones, it can be 3-5 grams per color. Although this is not accurate representation.

The computation for ink consumption typically involves factors such as the printing method, substrate, ink type, and desired print outcome.

The viscosity of the ink can impact its flow and absorption characteristics, which may affect ink consumption. While the size of the mesh hole, typically represented by the mesh count or mesh size, affects the amount of ink deposited on the substrate.

What causes the air pull of the substrate when screen frame is lifted?

Poor mesh tension allows more ink to remain in contact with the substrate. To mitigate the air pull effect and its relationship with poor mesh tension, it is crucial to maintain proper tension in the screen mesh. This promotes a clean separation during the lifting process.

Lack of adhesive applied on printing platens will also cause air pulling.

What causes uneven printing with white base inks on black substrates?

In printing spot design, it is very important to ensure that the previous coating is dry, before printing the next coat.

Check the mesh tension. It may be low, hence the mesh opening is uneven.

There may also be an issue with the platen, it may be damaged, if not dirty, hence it will need cleaning.

The website FAQ page(s) contain questions frequently asked over the years and may be updated from time to time. The answers are provided as reference and it is intended to be helpful and of assistance. Under no circumstances should any information contained herein be construed as legal advices.