Epoxy a nut into wood

[Jim Riseborough]

a table I am working on I want to epoxy a nut into the end of a piece, and then bolt it to another piece. For the look, I am using 7/8" dia bolts. I was going to epoxy a coupling nut into the end. I am thinking just Gorrilla or JB weld epoxy.

Its not in tension, other than the bolt torque, so I was not too worried about strength. Just to add a bit of mechanical adhesion, I was going to drill a few holes each side of the coupling nut.

Anyone see a issue, or done this before?

[Frank Pratt]

Done it. No issues. Scuff up the outside of the nut well.

[Jim Riseborough]

Done it. No issues. Scuff up the outside of the nut well.

Thanks for the feedback.

[Erik Loza]

What Frank said, PLUS de-grease the nut very well with DNA/acetone/brake cleaner/etc. JB Weld has worked well for me, for this type of thing.

Erik

[Charles Lent]

If you need strength, imbed the nut in the back side of the wood, so when you tighten the bolt it is pulling the nut further into the blind hole, not out of the surface of it. The epoxy then just needs to keep the nut in place.

Charley

[Doug Garson]

Why not just use threaded inserts with ca glue or 5 min epoxy? Same result, just easier to install. https://www.amazon.ca/Threaded-Internal-Diameter-Materials-substrates/dp/B088HGNM8T/ref=asc_df_B088HGNM8T/?tag=googleshopc0c-20&linkCode=df0&hvadid=459442063412&hvpos=&hvnetw=g&hvrand=7235706445535052145&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9001501&hvtargid=pla-942185225722&psc=1

[Bob Hinden]

I have started using Woodworking Thread Taps, see:

https://www.mlcswoodworking.com/shopsite_sc/store/html/smarthtml/pages/ww_thread_taps.html

I don't think they would work well for end-grain, but they work very well overall.

Bob

[Jim Riseborough]

This is for a table, that will be taken apart. I want it to last, worried threads will break, fail, et.c

[Charles Lent]

Use threaded inserts for that. They will be better than nuts and easier to install. I have never had one go bad, but they can be replaced, if needed. The tool that's available for installing them makes it easy and is very worth getting.

Charley

[Jim Riseborough]

Use threaded inserts for that. They will be better than nuts and easier to install. I have never had one go bad, but they can be replaced, if needed. The tool that's available for installing them makes it easy and is very worth getting.

Charley

Do they make a 7/8" insert?

[Frank Pratt]

That's a huge bolt to be holding a table together. I don't think you'll find an insert or t-nut that big at the local hardware emporium. Rampa fasteners, like a threaded insert on steroids, might come that big, but they'll cost a few dollars each.

[Mark Bolton]

I'm with Frank. I've never seen a 7/8" threaded inser or any other type of wood fastener insert. If you truly need 7/8" your on the right course. Id default to epoxy and a destructive mockup for peace of mind if needed.

[Bruce Wrenn]

I'm with Frank. I've never seen a 7/8" threaded inser or any other type of wood fastener insert. If you truly need 7/8" you to cpturer on the right course. Id default to epoxy and a destructive mockup for peace of mind if needed.


Can you cut a mortise to capture the nut, from back side? If so, use a square nut instead of a hex nut in the mortised pocket. A machiinest could make you a barrel nut to fit your bolt

[Jim Becker]

No issue. I'll add that in addition to the adhesive "holding" the nut to the wood, it's also removing any gap between the fastener and the pocket it's going into which further strengthens the relationship between the two dissimilar materials. Something that resists rotation because it can't go anywhere makes for a good situation. Embedded fasteners like this are more at risk from being forced "vertically" out of the recess with use but that risk can be reduced or eliminated by planning things such that they are pulled into/toward the wood which most folks do as a natural course.

BTW, you can use fasteners like this in a way that they are invisible through lamination of the wood, leaving only a hole for the "male" fastener to engage the embedded nut that's completely inside of the wood. Again, that takes planning but is a way to have hidden knock down or adjustment capability.

[Jim Riseborough]

Here is what I ended up doing. Epoxied it in. Like I said, there is no sustained tension on the bolt and nut. It will be in a horizontal position when done.
444509

444508

[Matt Day]

That’ll certainly do it, but I think I would have used bed bolts or threaded inserts or a wedged mortise and tenon.

Show us the final product when you’re done.

[Frank Pratt]

That should do the job, but because the nut is so big, the horizontal piece its epoxied into has been weakened. A 3/8" nut & bolt would have been more than enough.