you're reading...

Rudder stiffeners riveted

I decided to use some self-etching primer for the stiffener/skin union for the rudder. Making up a batch of 2-pack primer was going to see most of it thrown away. I plan to spray 2-pack primer over the whole lot when I finish fabricating, drilling and dimpling the rest of the rudder components so I can spray them all in one go.

After spraying some primer down the rivet hole lines on the skins and on the skin side of the stiffener angles, I let them dry and then clecoed them to the skins. I then picked some -3-3 flush rivets and popped them in the holes, holding them in place with some rivet tape. Next the skins were flipped over and I got my back riveting set and plate ready.

I would like to warn others at this stage to be very careful that the back plate is properly aligned with the rivets. I had 2 instances where I didn’t (1 on each skin). In the first instance, the plate’s edge was right through the middle of the factory head when I tried to set it. This almost split the rivet and it deformed the dimple in the skin and stiffener. I managed to drill this rivet out without enlarging the hole and ended up re-dimpling the hole with my C-frame. This is what the deformed dimple looked like after I drilled out the rivet.

The second instance was me just getting complacent. Things were gong smoothly and I was probably going a bit too quick. Consequently, I ended up trying to set a rivet with the back plate edge running across the edge of the rivet hole (i.e. in a tangent). This created a small crease (for want of a better word). I drilled out the rivet and de-dimpled the hole. This is what it looked like after I dimpled it.

The crease is not full thickness, and it is fairly small. I replaced the rivet and set it without any dramas. I’ll get my TC to have a look at it at his next visit to make sure it is OK.

Without any other issues I managed to rivet all the stiffeners to the rudder skins.

Build time 3.5 hrs.


About gstrack

Husband and father of 2. Control & Instrumentation Engineer. Flying nut. Gadget geek.


No comments yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: