The secret to using wheat (or rice) starch paste is all in the timing.
If you paste up a hinge and apply it too quickly after pasting, it will be too wet and will most likely pucker the art. If you wait too long it will be too dry and not create a strong bond.
Here is a simple exercise to help you learn how to time your hinge applications. Try this once and become empowered.
First “wet tear” 6-7 hinges. Do this by using a small brush and water to paint narrow stripes on a piece of medium weight Japanese hinge paper. Make the hinges about ¾” x 2” or so — longways with the grain. Let it sit for a minute and then tear the hinges by pulling the paper apart along the wet lines. This will create nice feathered edges on the hinges that help hide the edges of the hinges on thinner art work.
Next paste up all of the hinges at once by painting just the last ¼ inch of the tip of the hinge with paste. Apply the paste liberally to saturate the hinge paper with the paste.
Now apply the first hinge to the edge of a piece of bond paper or slick magazine page for your test. Blot it gently with a folded up paper towel and then put a small weight on the paper towel blotter for about 15-20 minutes. (Baby socks filled with b-b’s make great hinge weights).
Wait two minutes (it’s best to set an egg timer because you will get distracted) and apply your second hinge just like you did the first one.
Wait another two minutes and apply the 3rd hinge, wait another 2 minutes and apply the 4th hinge, and so on.
15-20 minutes after applying the last hinge you can do your tests. You’ll notice that the first 2 hinges were so wet that they puckered the paper. The last hinges were so dry that the bond was weak.
Do a shear test – that is pull the hinges straight out from the edge of the paper. You will be amazed that you will have to apply from 5-7 pounds to tear a well bonded medium weight Japanese paper hinge.
The last test on the remaining hinges is to “peel” the hinges back over on themselves. You’ll notice just how weak the peel mode is for hinges. This is why you never do “V-Hinges” – even if T'd- because the peel mode is inherently weak.
You have just learned how long to wait from pasting to applying your hinges to get the strongest bond without puckering the paper. When you hinge a customers' art, set your timer to accurately time your hinge applications. You will have to alter your timing on hot, cold, or humid days. Set your timer!