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Nutplate Tip

David Paule

Well Known Member
Recently, I added some Click Bond nutplates to the avionics shelf. That went fine. Since I was a couple short in one size, I saved the silicone stems and used them for the home-made ones I glued in.

Worked a charm.

Dave
 
Gluing in Nut Plates is a very bad idea. They might hold today but down the road if the glue let's go you are in a real world pain in the &ss! I have tried to do pre-purchase inspections and have found several that broke free. Then you scratch your head wondering how do we open or remove this now.
 
In this case they glued to a fiberglass avionics shelf. I was reluctant to drill so many additional holes in it for the rivets. Also, here, there is access on the nutplate side.

There are places where this is a very good idea and places where it's not. There are situations where the builder can have confidence in the bond joint and places where that would be unwise. I've learned that with suitable process control, bonding is reliable.

In this case I mostly wanted to share that the Click Bond silicone stems can be reused and do a great job of locating another nutplate - whether you glue it on or rivet it. This works better than a nutplate jig tool. In fact, they could probably sell just the stems along for this purpose.

Dave
 
Fare enough. On aluminum I wish they could stay put with glue they can save a lot of headaches but unfortunately it's horrible when the glue fails.
 
Since I built the little jet entirely with ClickBond products, I’ve got quite a number of silicone stems/fixtures in various sizes - and I do re-use them on occasion. I hadn’t tried using the dyes I’ve and stems with a standard nutplate - will have to experiment!

With proper surface prep, and using their adhesive, I have never had a problem - the few times I have had a nutplate come off, I wasn;t surprised - deep in my heart, I knew I hadn’t cleaned things properly…..

Paul
 
So after I finished painting my cowl I realized I forgot to add the nutplate for the cowl pin retainers. I tried to be slick and bond them on with epoxy. They failed on the 2nd or 3rd removal. The heat in that area doesn't help either.
 
"Oakie" Clickbond Anchor Nuts - DIY

Adding fuel to this fire, I have been using my own version of the Clickbond product for many years now with good success & quite a bit less pricey.

As you can see, this idea is a simple "marriage" of a conventional anchor nut (or nutzert, threaded stem, or other?) bonded to a base material (either aluminum or phenolic), with 3M 22126 Scotch Weld Structural Adhesive.

The beauty about this "system" is that the base pieces don't need to be symmetrical and the anchor nut doesn't need to be centered. Sometimes you need these things to go where getting enough surface area for good adhesion is not an option unless the nut itself can be offset enough to make is all work.

I tested (shear) a "coupon" just to make sure I wasn't going down a rabbit hole thinking I had a viable solution to the high cost of the Clickbond, and found it took 1500 lbs (2 units) to shear the bond. Test was made with the binding screws finger tight only, so as not to bias the result.

If you are so disposed, you can also attach them with 3M VHB tape - not as strong (perhaps), but instantaneously available for service.

Never had one fail yet.

YMMV - and probably will

HFS
 

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I don't know about using epoxy, but the Clik-Bond adhesive is a different matter. We use them on some very large structural components of spacecraft with no issues (other than ensuring that they don't exceed maximum AFTs). Follow the process spec precisely, and they work just fine on our little airplanes.
 
Adding fuel to this fire, I have been using my own version of the Clickbond product for many years now with good success & quite a bit less pricey.

As you can see, this idea is a simple "marriage" of a conventional anchor nut (or nutzert, threaded stem, or other?) bonded to a base material (either aluminum or phenolic), with 3M 22126 Scotch Weld Structural Adhesive.

The beauty about this "system" is that the base pieces don't need to be symmetrical and the anchor nut doesn't need to be centered. Sometimes you need these things to go where getting enough surface area for good adhesion is not an option unless the nut itself can be offset enough to make is all work.

I tested (shear) a "coupon" just to make sure I wasn't going down a rabbit hole thinking I had a viable solution to the high cost of the Clickbond, and found it took 1500 lbs (2 units) to shear the bond. Test was made with the binding screws finger tight only, so as not to bias the result.

If you are so disposed, you can also attach them with 3M VHB tape - not as strong (perhaps), but instantaneously available for service.

Never had one fail yet.

YMMV - and probably will

HFS

This is where I said why I didn't think of it. Great idea.
 
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