A hanger bolt is a double-ended bolt that is typically used to attach legs to furniture. Learn how to install hanger bolts yourself two different ways with this handy tutorial!
Adding legs to an existing cabinet or bookcase can completely change the look and feel of a piece of furniture. But how do you attach those legs to the bottom? I'll show you two different hanger bolt installation methods, so you can turn anything into a furniture leg!
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Since you're reading this, I'm assuming your new furniture legs didn't come with the hanger bolts installed already. It's commonly considered an add-on with an extra fee with the higher end pieces, but they're not difficult to do yourself!
But hanger bolts aren't just for furniture legs! They're handy for attaching wooden dowels to pegboard vertically (like in this DIY drawer organizer) or horizontally to make a coat rack (or this DIY ski rack).
They can also be used to screw finials to the tops of fence posts and staircase banisters.
What is a Hanger Bolt?
Glad you asked! It's a bolt with two different ends. Typically one end is pointy like a screw so it can go into wood, and the other has a flat end that is inserted into a metal plate or threaded insert.
The pointy end goes into the wooden furniture leg, and the flat end goes into a metal mounting plate that is screwed into the underside of the cabinet or tabletop.
The bolts come in different sizes, so make sure you have one that matches your hardware (this one is too small for the hole, but it's what I had laying around the shop!) You can find all the different diameters and lengths here.
This allows the legs to be removed easily for transport, or if you just want to switch up the look!
The tricky part about installing hanger bolts is that there's nothing to grip! Both sides are threaded, so using pliers will just strip or bend the little grooves. But there are two easy methods that you may not have thought of!
Predrill the hole first
No matter which method you choose for installing hanger bolts, you'll want to predrill holes in the leg or dowel first. Start by marking the center of the end.
On a circular piece like this dowel, I use a compass set to half the diameter to mark the center at multiple points. Where they all meet is the middle! For a square leg, use a ruler to mark an X from corner to corner.
Use a small drill bit to create a pilot hole first. This prevents the bigger bit from "walking" across the end and getting off-center.
Choose a drill bit that is a slightly smaller diameter than the bolt (preferably the same size as the center shaft). This will leave enough wood for the threads to grip onto, while clearing the way for the rest of the hanger bolt.
Mark the length of the pointy end of the hanger bolt onto the drill bit with a piece of painter's tape, so you don't accidentally drill too far!
Hold the leg or dowel steady with one hand while making sure the drill bit is perfectly straight. Stop once the tape starts brushing the sawdust off the end.
How to Install Hanger Bolts - Double Nut Method
All you'll need for this method is two nuts the same diameter as the hanger bolt (in this case it's ¼"), and a socket wrench.
Thread both of the nuts onto the flat end of the hanger bolt. Then loosen the bottom one and tighten the top one so they run into each other and can't go any further. Keep them towards the end of the bolt.
Now, choose a socket that tightly fits over the nut and attach it to the socket wrench. I have a kit with lots of different sizes, so it's just trial and error to find the right one.
Then use the socket wrench to install the hanger bolt into the predrilled hole!
You can also screw a cap nut to the end of the bolt and screw it it into place the same way.
Either way, just make sure you're screwing the bolt in straight, so you don't end up with crooked furniture legs!
How to Install Hanger Bolts - Hanger Bolt Driver Method
Ok, so all that nonsense with the first method is totally unnecessary if you have this special driver bit . . .
They're hard to find in stores, but for around $5 on Amazon, they're totally worth it! You can find the various sizes here.
The inside of the bit is threaded the same way as the flat end of the bolt, so you just twist it on by hand.
The other end of the bit is inserted into your drill chuck, then you just screw it into the predrilled hole in the furniture leg! You could install hanger bolts in all four legs in minutes with this method.
Easy peasy! Now that I know how to install hanger bolts with this driver bit, I'll never go back to the two nut method!
Screw the Hanger Bolt into the Metal Plate
Regardless of what method you use to install the hanger bolt, you'll need a metal plate of some sort to attach to the underside of your furniture. Some types have an angle built into it, so your furniture has that mid-century modern look.
Other brackets install the legs straight down. You can also screw them directly into the bottom of the table with threaded inserts for a cleaner look.
I've been thinking of adding feet to the bottom of the entryway bench I built last year, since it sits a little too low to the ground. Now that I know how to install hanger bolts, it should be a piece of cake!
Check out these other home improvement tutorials!
Hope
Tuesday 7th of April 2020
This was such an easy to understand post! I built a rolling cart in November and spent so much time researching how to install hanger bolts lol.
My life has also been changed by using your advice of just drawing a line between opposite corners for a square dowel. It sounds incredibly no-brainer once I read it, but honestly, I never thought of that until now!