A couple of weeks ago I noticed that the inside edges of my tires were getting pretty worn, so it was time to flip the tires on the wheels to get some extra life out of them since they wear faster on the outboard edge than they do the inboard edge. I did it on a Sunday afternoon and, as usual, it took twice as long as I thought it would.
At the end of the day, as I was getting ready to leave and was putting the right wheel pants back on, there were two nutplates that were badly damaged and the worst one I could barely get the screw in. In fact, I couldn't get it all the way in to where it was tight. I should have taken the pants back off and replaced them then, but it was late and I was tired so I figured I would do it the next time I had the pants off.
The more I thought about it, the more I felt uncomfortable with it. If I just happened to have a problem away from home, say a flat tire for instance, and needed to remove the wheel pant on the right side, I could be in trouble because I think this was bad enough that I may not be able to get that screw out, which could leave me in trouble. In fact, I feared that when I did remove that pant next I might have to drill out that screw.
Saturday 2/8/25 was scheduled to be a fairly crummy day so thought I would knock it out that day. After all, it shouldn't take more than an hour. Famous last words.
In fact, the weather turned to be much nicer than the weather guessers were guessing and I thought I could fly after taking care of this quick task. To be fair, for any reasonably skilled person, this shouldn't take more than an hour. If I did this kind of work more often, I don't think it would have taken more than an hour. At my current proficiency level, it took more than an hour.
I stopped by my Dad's hangar on the way in to turn on the heat and pick up my "Main Squeeze" hand rivet squeezer from Cleveland Tools. As I was removing the wheel pants, I remembered another nutplate that was also beginning to give me fits, this one riveted to the aft wheel pant itself.
Once my pants were off, it was time to drill out the rivets that hold on the offending nutplate. The rivets have a dimple in the center of the head and a person who is good can use that as a guide to drill off the rivet head. I am not that person. I have a hard time drilling a straight hole by hand under the best of circumstances and these were not they. It is important to drill through the center of the rivet and not enlarge the hole. To help me do this I start by hitting the dimple in the rivet with a spring-loaded punch to put a better dimple there. After that, I start drilling with a center drill.
The center drill is designed not to wander and is thick enough not to bend, making it easier to get a good start on a hole. Once the hole is started I switch to a #40 drill and finish up like a normal person. That all worked well and I got the rivets drilled out with no problems.
The fun began when I went to get a new nutplate. I was sure that I had all I needed on hand, but when I went looking, I couldn't find the right one. I knew there were more up in my Dad's hangar, so I saddled up and headed there to pick a couple up. It took me a minute to remember where I had put that stuff, but once I did it was no problem to get the two that I needed. What? I only need two, why grab more than that?
Once I got back it only took a little doing to get the new nutplate clecoed in place and ready to rivet. The riveting took a few minutes to figure out because I couldn't get the squeezer in there, the brake line was in the way. I had to unbolt the brake piston from the back plate and move it out of the way. With that done, it was pretty easy to set the two rivets. Now all I have to do is vacuum up the metal shavings and go do the other one.
Now it is time to do the other one. Drilling out rivets in metal structure is relatively easy. In this case, the pant bracket is fairly thick, so it is that much easier. Fiberglass is a different thing altogether. In this case the flange that the nutplates are riveted to is pretty thin and fiberglass is much softer than metal, so it is that much easier to enlarge, or in any other way, bugger up the hole.
When it came to the rivets in the fiberglass, as if that wasn't enough of a challenge, the rivet heads had paint on them and I couldn't see the dimple. In this case, there are two choices, first, sand off the paint until you can see the dimple or, B), just mark the middle of the head and pretend there is no dimple (we don't need no stinkin' dimples). I chose option 2.
I was able to get the nutplate drilled out much easier than I expected and managed to do it without enlarging the rivet holes. Hey, this is great, I'll have no trouble finishing in time to go fly. 😊
By putting a cleco in one ear of the nutplate and a rivet in the other, the nutplate is usually positioned in the proper place, once it is located in the first place. I did that in this case and was able to get it riveted in fairly easily. The main drawback is that the side of the pant half is not very rigid and you can't really bear down on the head with the squeezer to keep the rivet from setting proud of the hole. In this case, I got very lucky and ended up with two very well set rivets.
Bear in mind, that when I am actively building something and these skills are in frequent use, this is all quite simple. But I haven't been actively building for a few years and these are things I don't do very often otherwise.
Now all I had to do was put my pants back on and I could go fly. Sounds simple, yes? Should be. I got the rear pant reinstalled and the new nutplate was smooth as butter. I started to install the front half and things didn't go so well. A reasonable person might start with the new nutplate to make sure all was well. Not so in my case, I thought I would save the new one for last. Big mistake. Turns out, the nutplate was not quite centered in the hole and a screw would not go in. Please tell me I don't have to take this whole thing off and do it again. OK, I won't tell you, but...
Remember when I decided to only take two nutplates from my Dad's hangar? Yep, in drilling out the nutplate it left significant parts of the rivet in the ears. I figured that I would likely hose up the ears trying to get the rivets out. So, back up to my Dad's hangar for another nutplate. Now, a cautious person might grab more just in case. A really cautious person might grab the whole box they are in. Me, meh. One more is all I need.
After lunch, I tried it again. See, as mentioned earlier the metal bracket is thick and strong enough for the countersinks for the rivets to hold the nutplate in the proper place. In the fiberglass, however, there is enough slop that the nutplate can be riveted just enough off center that a screw will not go in. That is what I did.
To fix it, I used a trick that is usually only used to locate the nutplate and rivet holes correctly during the build process. I put a cleco in one ear of the nutplate, a rivet in the other and a really short screw through the threaded portion to keep that part centered in the hole.
Once the new nutplate was properly located, putting the rest of it back together was very easy. The good thing is that now all of the screws go in with no effort and I am not worried about one shearing off in the hole. The downside, it is now almost 3:00 and the I still have to preflight and mount the cameras. Also, the ceiling is starting to come down, just like the weather guessers said it might. OK, probably a good idea to call it a day here. So I did.
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