This came up in a recient discussion with a few building friends.

I use the normal Arrow stapler. I put a layer of 1" masking tape over the bottom and fire a staple through it to clear the opening. I very rairly clean it until it's really laoded up with dry glue. I peel off the tape and re-do it.

Once it got clogged and wouldn't work. Sometimes liquid glue gets into the firing mechanism. I boiled mine and it worked. Back in running condition. I gave it a shot of WD-40 for good luck.