Taping Nut Plates?

[Naruto]

I found the rod ends difficult to screw into the nutplates for the rudder. Is there any issue with taping the threads of the nutplates with a 3/8" X 24 tap? The rod ends now screw in much easier but I worry the tightness may have been expected to ensure a tight fit.

Anyone else ever worry that only six little rivets hold the nutplates to the rudder spar and the rudder is attached to the VS via the 3 rod ends that screw into the nutplates?

 

[G-force]

They are self locking, they are supposed to be tight. Avery sells a nifty tool to make screwing these in easier.

 

[Jamie]

I found the rod ends difficult to screw into the nutplates for the rudder. Is there any issue with taping the threads of the nutplates with a 3/8" X 24 tap? The rod ends now screw in much easier but I worry the tightness may have been expected to ensure a tight fit.

Anyone else ever worry that only six little rivets hold the nutplates to the rudder spar and the rudder is attached to the VS via the 3 rod ends that screw into the nutplates?

The nutplates are intentionally 'squeezed' after they are originally tapped to give it some 'grip'. It is supposed to be difficult to turn them! Best way to insert them is to use either a modified socket or a PVC tool. Search the archives for the correct socket size -- I forget what it is.

The reason there are only two rivets per nutplate is because that's all that's needed. The rivets only hold the nutplate in place while the bearing is being screwed into place. It's the *tension* from the nutplate that secures the rods, not the nutplate itself. This is true of all nutplates in the kit.

 

[Naruto]

When I tapped the nutplates, its easier to screw the rod ends in now. Did I just ruin the nutplates and have to replace them? That would suck if I have to drill out all the rivet on the skin to get to them.

 

[Ironflight]

I suspect that you already know the answer Naruto....as was stated above, the nutplates are designed to have a lot of friction to keep the rod end bearings from rotating or backing out. If these were floor screw or fairing nutplates, where a screw backing out would have no consequence, then heck, you could leave them loose. But think about the fact that these are holding your control surface on, and that if the rod end rotates and binds, you could have a tough day....If it were me, I'd bite the bullet, change them out, and chalk it up to experience.....

Paul

 

[AntiGravity]

Boelube helps

Dry boelube works miracles in helping reduce the pain of screwing things into nutplates...

 

[Bob Axsom]

Loctite

Yes, you have ruined the platenut's locking feature. However, you could leave it "as is" and install the rod end bearing studs with loctite when you know the exact installation depth you need. On my small rudder without a balance horn there was a lot of fine tuning to get it just right (maximum engagement of the leading edge into the vertical stabilizer) but maybe the "7" rudder is not so finicky.

Bob Axsom

 

[Naruto]

Thanks guys,

I just spent the last 5 hours drilling out the old rivets and installed new nutplates for the rudder and putting it back together again. I have to order replacements from vans because the ones I used were for the elevators. Oh well, better to be safe than sorry, especially when it comes to a control surface.

 

[jthocker]

rudder nutplate

If you think about it for a minute, how could that rod end back out anymore than enough to slightly bind in the hinge. I think you could have just torqued the jam nut, put some inspection laquer on the nut and if you were worried check the laquer every preflight until you realized that jam nut is doing it's job. Then check it closely if you ever feel binding in the controls and at the condition inspection.

 

[pierre smith]

Anyone else ever worry that only six little rivets hold the nutplates to the rudder spar and the rudder is attached to the VS via the 3 rod ends that screw into the nutplates?

Not since I tested the airplane to redline and 4 G's...... Van knows what he's doing.

Regards,
Pierre

 

[Mel]

Thanks guys,

I just spent the last 5 hours drilling out the old rivets and installed new nutplates for the rudder and putting it back together again. I have to order replacements from vans because the ones I used were for the elevators. Oh well, better to be safe than sorry, especially when it comes to a control surface.

If you haven't otherwise damaged the nutplates, you can restore the locking feature by gently squeezing them with pliers. You can then use them on the elevators. Look at other nutplates for reference.