I am going to be riveting a new drive chain sprocket on the clutch drum of my 1925 Harley JD and was wondering if there were any 'rules of thumb' on how far the rivet should protrude from the surface. The hole is also a 30 degree countersink. Experience years ago taught me that too short of a rivet is not good but too long of one is not either. I am going to have to do it free hand because my rivet set does not have enough throat - also heat or no heat?

All help appreciated. Jerry

Not a rivet expert, but I helped my brother rivet the sprocket on the hub of his 1948 Indian two years ago. It has worked perfectly and survived the Harley/Indian Challenge in Yosemite last yr. and the Challenge this year in Utah.
First and foremost.....have extra rivets. We did not use heat nor was it ever suggested by sprocket and rivet supplier. We tried using air gun with no success.....it was hard to control. We used solid backing on one side of rivet....I supported hub/sprocket and my brother used a proper "forming" tool with hammer to form rivet. We could actually tell by sound of final hammer blows when rivet was properly seated. It was more art than science.

You don"t form the countersunk side of the rivet head you buy a solid countersunk rivet you buck the countersunk side and form the opposite side head go to jay cee rivets or rivets online to see rivets

With a counter sunk rivet that side of the rivet.is flush the holding power of the head is already figured in, the diameter of the rivet will determine the other head size by the rivet snap or tool holder the rivet is actually smaller in diameter than the hole, once set and cooled it will fill the hole completely if done correctly the length of the rivet will be determined once the hole is filled completely and there is a little bit of flash left around the head this may require a trial and error piece first to determine length a chisel hammer has a different stroke than a rivet hammer you will not have success with the wrong tool heat is best with large diameter rivets you can do ok cold with rivets less than 1/2 inch diameter

As you probably know, you can get a tool for a air chisel that does a nice job. Different sizes for different rivets. I always have to guess at length of rivet also.

Where can I get the air tool?

Jerry

Jerry, Casecollector is correct, I have the air hammer & punch for it, you can borrow it. Call me.