Two Steps forward….

Not to be overly dramatic, but sometimes it does feel like it’s two steps forward, one step back. But more on that later…:).

 

Elevator installation was progressing quite nicely last post, and it was clear what next steps needed to be done…. so forward march I go! I needed to trim the flanges of the horizontal stabilizer to allow the counterweight arms to swing through. After mounting the HS and marking, I went ahead and did the cuts. 

 

Side note… I got those “Temporary Assembly Pins” for control surface mounting and IT… WAS….LIFE CHANGING! Best $21 I spent…please… just go get them right now. Do it.

With the elevators now able to sit “in trail” and aligned with the HS, I needed to drill the elevator control horns to secure them to the center bearing. To drill them accurately, I needed to create a little bushing that fits in the bushing and provides for alignment into the control horn. Easy enough. I did this to both sides, and fit the bolt through…. aligned! Whew. When I went to verify the fit, the leading edge of the elevator was rubbing against the HS. looking closer at the bolt, it was clear there might not be clearance to actually get the nut on the bolt… hmmm… what did I miss?

Something was wrong. Long story short, turns out I missed a critical measurement check when installing the rod end bearing. It needed to be 13/16″ off of the reinforcement plate… and I only read the max of 7/8″. This resulted in everything being too close to the aft spar of the HS. ugh. This was a big one that seems doesn’t have a good solution except to replace the weldments. The right side looks like it should be fine, but left won’t work. The good news is that the left side has the access hole for the elevator trim, so luckily this will mainly be a hit to the wallet ($90 per weldment), and a bit of time… but not much more. Pieces have been ordered and on their way today hopefully. I may just replace both for good measure. 

 

Last thing I noticed (very minor), was that I had put the bolts in backwards on the center hinge bearing causing the control horns to hit the nuts… a quick flip around fixed this issue.

don't miss that 13/16 measurement!

Well it had been a while since I made a flub like this… so it was just a matter of time. Next up with be the replacement work to get the new elevator control horns in when they get here. I estimate a few hours to get that done… then moving forward again! Until then… Happy Building!

2 comments

Leave a comment

Your email address will not be published. Required fields are marked *