applying silkscreen ink without a paste extruder?

Hi,

I was looking into creating some t-shirts with my printer and it could be done with fabric pens but those always look a bit flimsy, so I got some left over silkscreen ink from a friend who has a whole silkscreen carousel in his cellar.

The one issue that im foreseeing is that the ink is pretty thick/viscous and with that my idea of applying the ink with a felt tip marker doesn't seem feasible. Apparently the ink can be thinned with water but I want good colors.

I could build a whole paste extruder to pressurize that pen but that seems a bit overkill.

Any ideas on a different delivery method for these kinds of inks?

Cheers

If ink has high surface tension maybe you could use a capillary effect to deliver it to the surface.

How about using a bit of filament with a groove in it as a nib, you could retract it up through an ink reservoir to "dip" it. Then draw on the fabric after extending it again.
This assumes the ink is too viscous to readily flow through the gap between the filament and reservoir.
Advantage is you've already got everything you need to move filament about

By increasing the width of the groove along the filament you might be able to control flow a bit by how far you extend the filament after dipping... you'd have to compensate Z position to allow for the amount of extension of course.

... or make your own combined needle valve / nib by tapering a bit of filament, that might work better.

Two off the cuff things to think about

Cheers,
Robin.

Hm interesting ideas.

I thought about the capillary effect but I think the ink is to "pasty" for that, but dipping the pen in the ink might be possible. Maybe there is a sweet spot with only a slightly thinned down ink, where it gets sucked up by the pen. However then Im limited in how much I can draw.

I wonder if I could increase the normal gravity feed by putting a weight in the pen that pushes the ink down.

I'm not sure I understand what you are trying to achieve. Is the pen following a path to make a pattern on the t shirt? Is more then one colour being used? Are you using the ink in the pen, or using it as a means to apply a paste?

Why not just make a paste extruder? What are the advantages of doing it this way? Why not just make a manual silk screen set up? Could use printer for making stencils instead by hooking up a stanley blade to the gantry

I want to use the ink in the pen and yes a paste extruder that feeds ink into the pen would be the ideal solution but I want to exhaust the simple solutions first.

The pen would draw directly on the shirt, so cutting stencils and then manual painting could be avoided.

Apart from that your idea with the blade in the print head is interesting. I saw that once on a cnc where the blade would follow the cut line and i think it would be easy to mount a blade to a stepper motor but coding this behavior is too much for my skills.

... I'm using jetting valves for paste-dispensing - but it's a bit "pricey"

Here jetting a dot-image of the Liberty - [vimeo.com]

- and here more like 3D-printing - [vimeo.com]

This is the faster methode with up to some kHz pulsing rates (with low viscous fluids) -- would be much slower with pneumatic or motor driven piston-dispensers ...

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Interesting technology. Reminds me a bit of the objet printer. Do you get usable parts out of it with that UV curing method?

... yes - but can't post images for NDA's

The "usability" depends on material and intended use - it's perfect suited for prototyping seals and I'm actually developing an application for printing Braille text and symbols on preprinted stickers

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Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

I see^^, could that also print rtv silicones? or what are your seals made out of?

... it can handle most if not any fluids (or pastes) with viscosities from 100 to around 100000 mPas ... it will only have problems with fibers in the fluid, preventing the separation and acceleration of the trapped volume inside the nozzle hole ...

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Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

Quote
sungod3k
I want to use the ink in the pen and yes a paste extruder that feeds ink into the pen would be the ideal solution but I want to exhaust the simple solutions first.

The pen would draw directly on the shirt, so cutting stencils and then manual painting could be avoided.

Apart from that your idea with the blade in the print head is interesting. I saw that once on a cnc where the blade would follow the cut line and i think it would be easy to mount a blade to a stepper motor but coding this behavior is too much for my skills.

Would this actually be faster though? Silk screen set ups are very fast, especially with a bit of practice.

With your method you still have to set up the t-shirt on the 3D printer, and this is arguably about as long as it takes to set up a t-shirt on a silk screen! Options such as paste extruders or a blade/laser to cut a stencil are all well documented on the 'net and to me sound simpler then trying to develop a new method of applying ink through a pen. The blade/laser for making stencils can follow gcode from slic3r or S3D as well unless of course you want the blade to rotate, but this is not necessary if the blade is sharp and has a good point to it. I'm sure you could easily set the blade to rotate as the E axis as well if you wanted.

The only advantage I can see to using a printer instead is if you wanted to apply multiple colours or materials as it would legitimately save time and effort over a silkscreen. For example, 2 or 3 pens to make more complex designs or even an extruder applying flexible materials and a pen to do design work.

Youre right I probably wont get around a paste extruder and that has been on my list already for other stuff. It just sounded so simple in the beginning "just strap a pen to the print head", but it never is

For stencils a low wattage diode laser would probably be simpler but ill look into that later^^.

Multicolors would be very cool indeed, maybe Ill find/design the paste extrude in a way that you can change the syringes/pen really easy.