Adhering steel rod to wood

[joemodern]

Hoping to get some ideas about the best way to fix a stainless rod in thin wood. The photo shows the idea but isn't the real project. It is a 2mm rod I need to keep in place on a 6mm or so thick piece of wood, most likely mahogany. This a project that will hang on the wall as art and doesn't really have much load as it doesn't move but I do need it to stay put and it might be shipped so... There will be about a dozen of these points where I need the rod to stay in place.

I would have liked just to epoxy it there but does not seem practical given the small surface area. Anyone have any ideas regarding this?

 

[Bob D.]

Will the rod penetrate the wood as in your mock up, and will both sides be visible?

 

[DeformedTree]

Push-On External Spring Clip

How about these?  One on each side

 

[ryanjg117]

Probably the most important question is how much weight is being supported...

I like the spring clip idea. But if you need it to be "stealth" I would probably looks for M2 threaded inserts (something like this). Predrill a hole and then screw this insert in, then thread your rod in and put a dab of threadlocker in there to keep them in place.

But it all depends on load. I wouldn't be comfortable doing that with anything taking any weight. You'd want to use nyloc nuts and washers on either side for the most secure mounting.

 

[joemodern]

Thanks for the replies guys.

Yes, the rod goes all the way thru the wood. The load is less than an ounce. It really needs to look as if nothing is there at all so those clips would not work. I am not sure that a threaded insert on either side would fit although iI suppose I could use one insert if I can find reverse threaded rods the exact same. Something to look into.

 

[joemodern]

Is it possible to thread on the center of a rod? That would be ideal and a perfect solution.

I could also use threaded rod and then cover it with a stainless tube on top but that would complicate things. Might be the best off the shelf solution.

 

[Cheese]

Is it possible to thread on the center of a rod? That would be ideal and a perfect solution.

I could also use threaded rod and then cover it with a stainless tube on top but that would complicate things. Might be the best off the shelf solution.

You can.....however you have to start with a rod that has an outside diameter that's the same size as the major diameter of the thread size you're using. You'd thread the rod to whatever length you need and then reduce the diameter of the rod to the minor diameter of the thread size you're using. Not really a fun project if you're using stainless.  [crying]

If you have a lathe, another option would be to knurl a small section of the rod. Knurling actually increases the diameter of the rod and would provide small grooves for the retention of epoxy. However I think the rod would have to be larger than 2 mm.

If there is only an ounce of force on the rod, I'd just experiment with an undersized hole and then press the rods into the smaller diameter holes. You could then also machine a couple of small grooves in the rod which would act like keys if you were to epoxy it in the wood.

 

[joemodern]

The outer tube would not need to be that close to the inner threaded rod as it would just cover it up as a decorative function only I think, unless I am missing something. I can start with some epoxy and machining the "keys" as you suggest.

 

[Bob D.]

You said a 2mm rod.

I wonder if threaded inserts are available (maybe in brass) in a size that you could
drill out the center of the insert to 2mm, then epoxy it in place on the rod, and use
the external insert threads to fix it in position in the wood.

Or maybe something like this. Look at the plastic inserts, they are press fit on the OD. You could drill out the center or find a size that will allow your 2mm rod to pass through snugly and epoxy in place.
https://www.mcmaster.com/threaded-inserts

 

[RKA]

Long shot - I wonder of you can find a clear rubber type bushing to put into that piece of wood (try mcmaster.com).  The material would need to be flexible.  It would have a shoulder on one end to keep it in place as you push the rod through.  But if you found one sized correctly for the rod, as the rod is pushed through it should increase the outer diameter of the bushing slightly thereby keeping it secure to the wood.  It would be fragile, only enough to handle it but not enough for much else.  Any side load parallel to the wood and that shaft would get skewed. 

 

[Koamolly]

Can the wood be two pieces glue together?  Might be able to braze or solder a thin washer to rod and laminate between wood.  Or maybe drill a small hole and insert a pin?  See if just a pin provides enough reinforcement. Glue everything together with epoxy.  One advantage to two pieces of wood, it will be easier for a clean joint on outside since you will be applying glue inside.

 

[Stone Message]

How about sinking a 1 mm pin through the wood and rod then fill the small hole with your normal filler? You could have a small wipe of Araldite as well if you wish.

Peter

 

[Svar]

Keep it simple. If the load is less than an ounce make few grooves/scratches with file where rod contacts wood and epoxy it.

 

[Steve1]

Adhesive is not going to adhere well to the steel.  I think you need to cut some grooves into the steel rod for the adhesive to lock into.  Can probably chuck the rod into your drill and cut the grooves with a small triangular file, or just put the grooves in by hand. 
You will also have a problem that the adhesive will tend to get wiped away as you push the rod into the hole.  So I would suggest PL Premium for the adhesive.  It will tend to get wiped too, but any remaining adhesive will expand as it cures.  Maybe keep the hole a little oversized to minimize wiping of the adhesive.  After one hour, you can scrape off excess adhesive.

 

[Mario Turcot]

Tap a thread into the wood and use an allen screw  [big grin]