Attaching Threaded Rod to Timber

Nut insert?

Rod wibbled on Sunday 25 October 2009 18:16

Does it need to be strong in tension or laterally?

How about

Other than that, 2" square plate washer (builder's type, Screwfix) and a nut glued on the back. Drill holes and screw on, trapping the semi-captive nut between the washer and the wood - drill a clearance hole into the wood so nut can recess.

Or just araldite the stud into one bit of wood, then do nut up on the other.

If that had four screw holes instead of four spikes, I think it would be fine. But the threaded rod will be in tension so the tee-nut would have to go on the visible outside of the time hence not acceptable to the higher authorities. :-)

Currently searching the rest of that site to see if they have anything else that would do.

Thanks - it was close. And very quick. :-)

Rod wibbled on Sunday 25 October 2009 18:29

Try B&Q. Some metal table legs are screwed into a round plate with 4 or 5 holes via a single stud. That stud *might* be M10.

Umm, drill a large hole in the "other end" sufficient for the washer and nut and to recess the same below the surface of the timber then blank off with a plug.

Drill the necessary holes in it for the screws - and use dome head screws to take the tensile load - would that not work?

If there is a problem with the dome heads that stops the two pieces of timber from making contact with each other, simply drill holes to accommodate the heads.

Falco

The link was to a tee nut rather than an nutsert/nut insert.

Bit worried about those - in a nice hardwood like oak or beech, I'd probably be happy. But this is non-specific softwood and I don't think I'd trust them.

That's possibly why my brain was imagining a large flange with four well spaced screw holes.

Unfortunately it is not going to work. The timber is too thin to house the nut and a plug as well as retaining enough thickness to take the tension. Also, the timber is already fully finished.

Polyester resin as used in attaching studs to brickwork?#

Malcolm

Threaded wood insert? These screw into a hole via an allen key, take metric screw/bolt?

Dowel screw? One end woodscrew, other end metric?

T-nut as already suggested.

I assume a neatly countersunk allen/torx stainless screw is out? Or security-type with twin-pin (bit excessive, but gives a different appearance than "held together with bolts".

Counterbore the visible side, bolt through and then insert a plug of the same wood? Should be virtually invisible.

SteveW

I think that is what Steve Firth suggested. The wood isn't thick enough to allow that and still have enough strength to take the load on the nut/washer.

That looks as if it would be fine - but jolly expensive!

Rod wibbled on Sunday 25 October 2009 22:47

How many do you need?

How about the fittings for attaching things like sinks to walls? Threaded (for the nut) on one end and with a screw thread on the other. I'm pretty certain the ones I bought a while ago (Wickes but they have them in S/Fix / B&Q) were M10, but it rather depends on how long you need it to be and how much thread needs to be accessible between the two timbers.

Car body filler! Oversize the hole a little so it doesn't have to be perfectly aligned.

Hard to say definitely, without knowing more about it.

Can you make a hole, so long as nothing protrudes afterwards?

Can you make a hole and plug it?

Where are the forces acting? Tension in the rod? Shear? As you're using M10, presumably there's a significant force involved and any "attachment plate" would itself have to be well attached.

I suspect I'd be looking at a mortice into the end of the timber and the rod screwing through a nut & washer dropped down this mortice. However that also reduces the thickness of the timber that's taking the load by a significant amount. There's also the risk of rain collecting in there and rot.

I guess I'd probably end up drilling a counterbore and having a hole visible, but without the protrusion. A totally hidden fixing would be either too awkward, or too inefficient in terms of timber thickness / load.