The International Cessna 170 Association

For those who ordered rivets they’re in the mail. Thanks for the orders. Let me know who is ready to install the rivets and I’ll send you the HT-179 tool to roll the tail. I’ll pay for shipping if you’ll pay to send it to the next guy. If the tool gets lost the guy who loses it gets to buy a replacement for $25.

Gene asked about installing the rivets in the control yoke. Here’s a screenshot from the Cleveland Wheels and Brakes Maintenance Manual. This shows what to look for when installing rivets on brake pads. Their criteria is probably worth following when installing these similar style rivets in the control yoke. To minimize cracks on the rolled tail I greased the tool and made sure the end of the rivet was as smooth as possible. I am unaware of any guidance from the FAA on installing semi-tubular rivets. Unlike a regular AN470 or AN426 rivet these rivets do not expand to fill the hole so the rivet should be snug in the hole before squeezing it. Like the rivets on a brake pad, all the load on these rivets is in shear. There is no need to squeeze the rivet super tight. Doing that would only risk cracking the aluminum yoke casting. Only squeeze the rivet tight enough to eliminate any vertical play.

As you can see in the attached photo, I experimented with installing a rivet in a block of oak. Using a hammer and the HT-179 tool as a drift is the crudest way to drive these rivets yet it worked OK. There was one small split on the outer circumference. I didn’t have enough hands to use my hydraulic press. Later I thought of mounting the HT-179 tool in the vise and driving the head with a rivet gun. Another idea would be to shorten the HT-179 tool, drill a hole in the vise jaw to accept the rivet squeezer die for the rivet head, and use the vise to squeeze the rivet.

What is critical when doing this is to get the total length of the rivet correct. When the rivet is inserted there should be 0.137” sticking out as clinch allowance. The other dimension that needs to be correct is the depth of the hole. Too shallow and the tool will bottom out in the center of the hole before completely rolling the rivet tail. Too deep and you risk squeezing the aluminum casting. Practice with a block of wood and the remains of the rivet you drilled out. If you muffed up and need another rivet just send me an email or PM. For the cost of shipping ($3.50) I’ll send you another.

Thanks Gary. Very good information. Much appreciated.

Think you could modify a rivet squeezer to work?

Would the c-clamp type setting tool for brake lining rivets work on these yoke rivets?

lowNslow wrote:Think you could modify a rivet squeezer to work?

My 1” hand squeezer gives me 3/4” gap when both dies are in place. A 2”X 2” yoke like this one from the Yardstore would work if you could find a die to roll the tail of a 7/32” tubular rivet. Of course with a lathe you could easily modify the HT-179 rod into a die for the squeezer.

cessna170bdriver wrote:Would the c-clamp type setting tool for brake lining rivets work on these yoke rivets?

The brake rivet tool shaft is designed for a smaller diameter rivet. But with a drill press one could easily enlarge the diameter of the top hole in the yoke to fit the HT-179 tool.