I've never tried (or had to) do this, but one of my manuals lost a staple somehow and I'm wondering the best way to put it back together. The manual is mint, so I don't wanna mess it up. I only have regular staplers and they are not deep enough to reach into the crease to staple it. Does anybody have any ideas or tried it themselves?
Get a strip of staples and carefully bend one of the pins of the end staple, it will eventually break free of the rest. Straighten it if its out of shape, then feed it through the holes in the manual, then bend closed when through. You may find the staples you have are too wide, if thats the case you can unbend one of the pins (into an "L" shape) then re-bend it to the right size. It won't look perfect, but it will save any damage to the manual.
I find that the best way is to get a normal stapler and put a small amount of pressure on it so that the staple is just coming out. Then open up the ins book till you find the middle and carefully put the staple throught the old holes and firmly press down enough so that it staples. Just don't slam down on the stapler like you normally would. This way has a bit more risk of damage than Tachikoma's but the staple will look right.
