kitty kilian

It’s a Yudu

Suppose, just suppose, you are an artist and you want to do screen prints.

At home, that is. Not in some huge workplace working with big lighting tables and drying racks and all that, often paying high rents.
Nah, you just want to do the occasional print in between all those other nice techniques you are pursuing. So you need something small and practical.Something that can be put away in between printing rounds.

May be a Print Gocco?

Something like a gocco machine, that wonderful Japanese invention from the 1970s that makes mini-screen prints. The Print Gocco lets you expose the screens and print them, all in one tiny plastic and – let’s face it – rather cheap looking boxy device. Yet many artists around the world are using it still, even though the Riso factory has stopped making them. I guess with the appearance of personal computers and printers, making your own postcards has become so easy that not all Japanese families want gocco’s for their kids anymore. So Riso cut the production. So far they have not given in to many pleas from the save gocco movement to restart.

You can also read about using a Gocco here. And for Gocco lovers: I just found that a successor is on it’s way. Read all about it on this website by the german Günther Panenka – and learn more about the thermofax technique gocco is based  on.

Or a Yudu?

I was thinking about getting a gocco nonetheless, because I want to be able to make small screenprint editions.

Then someone told me about a new screen printing machine called Yudu.

A what?

Because of its name I figured at first that it would be Japanese too, but is is an American invention.

In the US this machine has been getting some attention, and there are a lot of sales points, but over here in Europe no one knows about it. Nonetheless the Dutch craft firm Kars has been selling them up until a couple of monts ago. Don’t think of calling them – they have discontinued the Yudu. They told me the machine is too difficult to handle for people who don’t really know how to screen print, they were getting way too many complaints.

So I got mine from Ebay and imported it from the US. The postage cost almost as much as the machine itself. Plus some extra tax when it entered the country – so my advice to fellow Europeans is:  buy one when you are on holidays in the States and bring it back with you. Through Ebay it costs about $ 150. But beware, the box is huge and it will fill an entire big suitcase. On top of that you will need an adapter, or transformer, or convertor, if you are on 220 volts like we in Holland are. It actually took me a long time to find out which transformer I needed, since Provocraft gives out no such technical specifications anywhere in their manual. But Europeans need a step down transformer that will generate up to 250 watt – to be on the safe side. My technical brother in law did the math for me and decided 150 W should be fine, but I got a 300 W one since it was the best buy I could find, for € 39,50.

The Yudu, like the gocco, can expose a screen for you. It also has a drying compartment. And it makes a table for the actual printing.

I studied many forums and websites about Yudu. Apart from the different voltage there seemed to be some more setbacks.

Yudu problems

• The materials to screen print with that Provocraft, the American producer, provide are ridiculously expensive.
• In forums you find a lot of complaints about the drying compartment which does not seem to dry well enough.
• And a lot of people just give up on it.

Yudu solutions

But it quickly turned out that

• any water based screen printing medium also works with the Yudu. No need for the Provocraft emulsion sheets of $12 per 2. (Go to Hacking the Yuduscreen and learn all about it).
• the screens can be dried with a blow dryer or a fan too
• a lot of people love it.

Yudu advantages over Print Gocco

Plus of course the Yudu has a few huge advantages over gocco:

• its screen is way bigger: 30 x 40 cm (12 x 16 in)
• with gocco, you can only use the lamps for exposure once, the yudu lamps can be used over and over
• it doubles as a lighting table
• it has a built in drying rack (though not everyone is pleased with it)

So I wanted to give it a try.

Most people who posted something about Yudu were t-shirt sellers, by the way. Yudu was probably invented with them in mind. The first Yudu screen was a 110 mesh, which is fine for t-shirts but not so good for fine screen prints on paper. Recenty Provocraft has added a 220 screen to their range of accessories. So I ordered one of those too.

Trying it out

The big box arrived and I got some liquid emulsion (Azocol 133 + diazo no 23) and a better squeegee than the useless one that comes with the yudu.

This afternoon I started trying it out.

Trying out the Yudu for real.

First I printed one of my designs on a transparency – in this case I used the transparency that came with the machine.

Applying emulsion to the screen

Next came the arduous task of putting liquid emulsion on the 220 mesh screen (which is a finer screen that Yudu just brought out, expressly for use with paper). I actually did not even bother with the emulsion sheet that came with the machine, having bought the much cheaper liquid emulsion already. I used Azocol 133 + diazo no 23, which you first have to mix and then store in the fridge. For more information on which liquid medium to use, go to Hacking the Yuduscreen. Dutch readers might want to check out joriso.nl, who gives a lot of great tips about DIY screen printing. If anyone knows of an emulsion that is less light sensitive and gets sold in smaller quantities than 1 kg I would be very happy to get some tips though! (May be this product would be better?)

Joriso says you do not really need a scoop (holrakel) to put the emulsion on. Just use your squeegee, he advised. I decided to give that a try.. but with one hand holding the screen (in a small sink!) and only one other hand to pour the emulsion on the squeegee AND pull it upwards in one nice continous movement, I turned out to be one hand short. After a few tries my emulsion was on the screen, but it certainly did not win I st prize. (As you can tell even from the picture below where the screen covered with emulsion is placed in the Yudu). So I do need to get a scoop after all.

I applied one coat to the back first and then another coat to the front of the screen.

The emulsion is light sensitive so I darkened the bathroom window with a couple of sheets and was as careful as possible about exposing it to strong light.

Drying

The drying compartment is right under the numbers you see lighted up in the picturebelow. You can just shove the screen in.

The drying cycle can be set again and again. I experimented a little and found that 30 minutes did the trick. On a You tube video I had heard someone say to keep the little door of the drying unit open, because he found it worked better that way, so I did that, too.

Exposure

Next I put the screen over the transparency copy and took a quick picture (picture above). Then I did what the Yudu manual tells you to do: I put the platen over the screen..

closed the lid and put a heavy weight of 5 kg on top.

\

For exposure time I tried the advice of the Hacking the Yudu screen website: 10 minutes.

This is how it came out after exposure.

Washing off excess emulsion

Light at shis stage is not a problem anymore.

I took the screen to the bathroom to wash off the excess emulsion.

And to my surprise and great joy the screen was perfect!

Of course there were some blotches because it had been so hard to put the emulsion on – but I would cover them with tape before I started printing.

A detail of the screen after exposure and cleaning. Yes, there are a lot of tiny specks of dirt, I wonder where they came from? But as you can see the white lines – where the ink will go through the screen and onto the paper – are just fine.

And finally: printing

First we need to do some repairs.

Repairs to the imperfectly coated screen

Here’s a close up of the screen ready to print.

Since my emulsion wasn’t applied very professionally (see Yudu post 2) there were some holes in the coating which would let ink through in unwanted places during printing. Yet since there were only a few large holes I could simply tape over them on the back of the screen and voila.

Next I put screen printing tape around the edges of the screen to stop ink from leaking through.

I also covered up some more of the screen since I only needed to ink over the white lines that  you see in the picture.

The great thing about the Yudu is that it also is a screen printing table in itself. The top hinges and can be tilted – and will stay up. Very simple and elegantly constructed I think – no fussing with weights etc. You just apply some force to move it up and down.

Some basic explanation of screenprinting might be useful at this point

When you start your printing round first of all you need to fill the tiny holes in the screen with ink like this: you tilt the screen upwards and apply ink on the top of the screen.  Next you pull the sgueegee towards you and then you take the rest of the ink back up again with your squeegee- all the while keeping the screen up. Now the screen is inked but the paper has still been untouched.

Next you let the screen down over the paper and with you squeegee you pull the ink from the top of the screen down towards the bottom in one quick and steady movement. Then you have to tilt the screen up again and take back up the rest of the ink. Apply a new sheet, may be some new ink, and repeat.

Some warnings

It is easy to make mistakes when you are starting out – I have made them all! If you for instance ink the screen twice, the paper may stick to the back side of the screen and when you pull it off it may smudge. If for any reason ink then sticks to the back side of the screen, you have no option but to clean the screen with water, wait till the screen is dry again and start over. Also: you need to keep the holes in the screen filled up at all times (to prevent the ink from drying even faster than it already does and clogging up the holes in the screen). This means that after making a print you always have to take the sqeegee with enough ink back up again, then rest the squeegee like you see in the picture below, may be apply some more ink, put a new sheet of paper in place.. and make your next print. All the printing needs to be done in one session and afterwards the screen needs to be cleaned rightaway. If you want to print the same image again, you can store away the screen for later use. Otherwise the medium needs to be removed with the proper cleaning liquid.

Putting some more ink on..

…and there you go, you have made another screen print.

Since my paper was cut to the exact size of the printing table and since the image was neatly in the middle of the screen I did not need to worry about exact paper placement. I was only doing one color run too, since I intend to color these prints with watercolor. As soon as you start doing multiple colour prints, registration becomes necessary.

Later in the afternoon my studio looked like this..

And I was really happy with the results. I honestly could not have done better in any professional screen printing studio. The prints are crisp and clear. Critique I heard on Youtube about the screen nog being taut enough for good results does not ring true so far. I don’t know how the screen will hold in the long run. But for now, here are a few closeups:

And closer still:

I welcome your comments, questions and tips!

Jun 17, 2010 | Categories: Uncategorized | Tags: 110 mesh, 110-220 volt, 220 mesh, adapter, adaptor, belichting, converter, europe, gocco, holrakel, how to, how to apply medium, it's a yudu, lighting, medium, mesh, nederland, rakel, screen print, transformer, voltage, water based inks, watt, wattage, zeefdruk | Leave A Comment »