Monday, November 15, 2010

diy: screen-printing, and re-covering an upholstered chest



This chest has gone through several iterations since my childhood, when it was covered in a folksy, floral tapestry fabric. I prefer it now, but that may just be because it's not covered in creepy Madame Alexander dolls given to me by a well-intentioned (and well-loved) aunt.

This is a how-to on screen-printing and some very elementary upholstery - a crafting buy-one-get-one-free.

Supplies for screen printing:
  • your image, laser-printed onto one or multiple transparent slides, or drawn onto transparencies with opaque ink
  • Scotch tape
  • a piece of glass bigger than your image (the glass from a picture frame will work well)
  • stretcher bars for canvas
  • craft or wood glue
  • screen printing silk
  • staple gun and staples
  • photo emulsion for screen printing
  • squeegee
  • screen printing ink
*for the silk and the ink, you'll need to evaluate which type is best for your specific project.

First, set up your design. For my mums, I copied two different blossoms from a vintage tablecloth that I love, and had several of each type printed on a transparency at Kinko's. I used invisible tape to arrange them on a large piece of glass.

The images you create should exactly match what you want to show up in your final print. Draw, paint, or print only the areas where you'd like to put ink, and leave the rest blank. It's a "negative" only in the sense that your silkscreen will be empty where you want the images. The point is to eventually pass ink through these areas.

I measured my composition, and assembled a frame with canvas stretcher bars, glued in the corners. It was big, unwieldy, and warping, so I reinforced the corners with smaller stretchers.

Then I attached the silk. Working out from the center of each side, staple the silk as tautly as possible to the frame. Once it's attached, go back and staple in between your staples, to eliminate as much tight/loose variation as possible.

Now, follow the directions on your photo emulsion to apply the emulsion to the screen. The emulsion, obviously, is light-sensitive, and the goal is to get a thin, even coat of emulsion onto the screen as quickly as possible. I generally work in my bathroom, where I can easily cover the one small window while I work. Get the emulsion all the way into the edges of the screen, and only work with a small amount of emulsion at a time. Too thick a coat will drip and cause textural variations as it dries.

Once the emulsion is applied, it will need to dry. I always have a large, flat cardboard box ready to slide the frame into, which I then cover with a blanket and slide under the bed. The emulsion will need a few days to dry completely. Be careful when you're moving it - the stuff stains, as the bottom hem of our bedspread can attest.

When the frame is ready, set up an exposure station. Check your emulsion bottle for details on distance and exposure time. I always expose at night, so that I can make sure my bulb is the only light source. Position a lamp above the spot where your screen and image will be, according to the emulsion's directions.

You'll want to eliminate any tiny gaps between the surface of your screen and the negative image, which would cause shadows, and thus fuzzy edges on your image. Place a folded towel or a piece of foam on the underside of your screen to keep it from sagging, and set your negative on top of the screen, followed by a piece of glass to weigh it down. Switch your light on and turn on a timer.

The idea with photographic emulsion is that light sets the emulsion. Wherever the emulsion doesn't see light, it will wash away. The trick - and a good reason for closely following the product's timing and wattage directions - is to find the perfect balance. On an under-exposed screen, all the emulsion wants to wash away. On an over-exposed screen, the light that inevitably seeps through starts to harden the image, where you want the emulsion to wash away.

When the exposure time is up, hurry your screen into the bathroom and turn off the lights. Spray the screen, brushing it lightly with your hand or a rag if necessary, until the emulsion on the image starts to wash away. The edges of the image may need a little more work than the center. Now let your screen dry - the hard part's done!

When your screen is dry, place your fabric over a piece of plastic on the floor, or on a surface that can easily be wiped down - the paint likes to seep through a little. If you're doing a t-shirt, place a piece of paper inside the shirt.

Position your screen over the fabric, and place a small dollop of ink onto an exposed area - not the image - or a couple of dollops if you're doing a large surface like mine.

Use your squeegee to spread the ink in every direction - up, down, left, right - several times. Don't be afraid to go a little overboard, and to press hard - but make sure not to let the screen shift while you work. You want to distribute the ink thoroughly through the pattern, because it's almost impossible to reposition the screen exactly and give it another coat.




If I'm doing a large, spread-out pattern like this, I often pull the print once, then position the screen on another part of the fabric and do it another time (below-right image). If you do this more than once, you'll need to clean the front of your screen, or it will start to pick up and leave ghost images on your fabric.

Leave the fabric to dry. The ink's instructions will likely tell you to iron the image to set it, but I rarely do this. On washables, like t-shirts, I don't mind a faded image, and I hardly ever wash upholstery fabrics enough to fade them.

Upholstery materials:
  • screwdriver
  • bump-cloth
  • muslin, optional
  • hand-printed (or store-bought) fabric
  • staple gun and staples
This part is super simple, and gets easier after practice. Because we always have our feet up on this chest, the fabric wears out every six months or so, and I replace it - usually with the same printed pattern.

Unscrew the surface you're going to upholster. On my Lane chest, I unscrew the whole top at the hinges, then unscrew the particle-board top from the wood bottom.



I've never bothered to remove the old fabric. Just place the top, top-down, on the muslin and bump-cloth, so the bump-cloth winds up on the inside. Now, work out from the centers of the long side, putting a few staples on one side, and then moving to the other. Pull the fabric very tight. Make hospital-corner-like folds at the corners.


Repeat the process with your finish fabric. Trim the fabric from around the screw holes.


Screw the top back together, and screw the hinges back onto the chest. Savor your accomplishment by mixing a gin and tonic and pressing "play all" on a DVD of Arrested Development. Kick up your feet. Feel cushioned? Well done.




7 comments:

  1. Coach Fowlkes approves of this post.

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  2. This is a brilliant tutorial. I did screen printing when at college, and had completely forgotten how to. Thanks ever so much!

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  3. Just found my weekend project. Was looking for something for under the family room window. Thanks

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    1. I wanted to leave a little comment to support you and want you a good continuation. Wishing you the best of luck for all your blogging efforts.

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