I assume that you mean the timing chain link tool. That tool makes a crimp that is very pretty to look at, but if you're not in the habit of removing the valve cover to admire the beautiful crimp in your timing chain link, here is a very good alternative.

Before putting the lock plate in place, run your finger over it and feel for the side with sharp edges. Put the plate in place with the sharp edge IN. That puts the rounded edge of the holes out where you will peen the ends of the master link. By using the smooth edge, you will have more area and a tapered area for the peening to force the pin end into.

With everything in position, which will require the link to be at the very top of the sprocket, use a body dolly at the rear and the round portion of a ball peen hammer to peen the pin and mushroom it into place. If you don't have a body dolly to back up the master link, hold the head of a large hammer in your hand and use that.

This method works great as long as you keep the plate pushed back while beginning your peening.

Imagine, using a ball peen hammer to PEEN with.