Turning Archive 2005
>Clem The pin is tapered. Try to find the narrow end and put it in. Then tap it with a hammer. I didn't hit mine very hard, just a firm gentle tap. It hasn't come out since. They must not put these in very firmly because my best friend has his drop out also. Neither of us have had any problems after reinstalling them.
I would suggest if you own a 3520 that you check this pin, which is on the underside of the quill inside the tailstock cavity. Just tapp it with a hammer and you shouldn't have any problems.