This is my tutorial for cutting down a 22" tapered store bought table leg, re-threading it and ready to install.
These legs come in a variety of sizes, 6",8",12",22", and 28" you can usually find them at your local depot, lowes or you can order them online. They fit into a standard mounting bracket and are great for someone who doesnt have a lathe, or wants to make a quick table.
Sadly they do not make a chair or bench height size, so we have to cut them down to the right size.
Estimated Time of project: 30 minutes for 4 legs
Small bubble level
Scrap wood shims
Hand grip clamp
Drill with a 1/4th drill bit
Forstner or Spade bit
Medium sized bar clamp (optional)
Circle Center Marking Gauge (Which can be found here https://www.instructables.com/id/5-minute-circle-ce... shameless self promotion)
Now... onto the project.
Step 1: Removing the Threaded Screw
First thing we need to do is remove the threaded screw from the table leg.
These legs usually have a staple and a tag attached to the top, I've already pulled the tag and the staple from the ones pictured.
Removing the thread is pretty easy, just clamp the thread into your vise, apply a decent amount of pressure, and lefty loosey the table leg.
If your thread starts to slip inside the vice, clamp it down some more. There may be a little damage to the threads, but when you screw the finished table leg into the mounting bracket, the threads inside the bracket will cut through the damaged areas. Just try to keep your clamping points consistent throughout this process to keep as much of the threads intact as possible to allow for easy use once its finished.
Once you've removed each threaded screw, place them somewhere safe, they do sell these separately but no sense in buying replacements when you can just not lose the ones you already have.
Step 2: Measuring for Your Total Height and Cutting Your Legs.
I'm building a bench for a client, (which will be my next project for here) they want the overall height of the bench to be at 18". So I flip the bench onto its top, measure from the table to the top of the mounting bracket where the finished table leg will rest. That works out to 2 1/4", subtract from 18 gives us 15 3/4". Measure from the bottom of your tables foot and mark out your distance you need.
Now take your table leg and put it on your miter saw, I have an feed extension that I built that extends the flat plane of my saw table out about 8 feet. This way I can clamp down stop blocks along it so I only have to measure once for repeated cuts. Saves a lot of time. If you dont have something like this or cant rig something up, you're going to have to measure out each one of your legs, but be accurate and make sure your saw is always cutting on the same spot on your measured line. Otherwise your table legs will end up uneven and you'll get a wobbly bench/chair
(If you're reading this and would like a step by step on how to make an extension for you miter saw, shoot me a message or leave a comment and i'll make one)
Now things get a little tricky, since the table legs themselves are tapered, just slapping them up against the back of your guide fence will result in a table leg with a slight angle at the top, which is no good for what we need. So grab some shims and your small bubble level, and shim up your table leg until its level. That takes care of one axis, now we have to deal with Y, for the most part the taper on these legs doesnt really start until an inch or so down from the mounting point. So you can kind of cheat and hold the very top of leg against the fence, with a decent amount of pressure. This will pull the bottom of the leg out away from the fence and should line it up close enough to make the cut. You still might have a slight angle at the top of the leg when you're done, but we can take that away with sanding.
Repeat this process for all 4 legs
Step 3: Marking Your Center and Measuring Your Depth.
Use your brand new trusty center circle marking gauge that you just built and mark out all your legs.
Then place one of the threaded screw ends down on the table lay your 1/4th drill bit next to it and mark with your pencil the depth you'll need to drill, making sure to leave enough thread at the top to screw into your mounting plate.
Then take some tape and wrap it around your drill bit, leaving a little flap off to the side. This is a good way to be able to tell your depth without having to really have to pay attention. Once the tape flat gets down to the depth desired it will brush away all the saw dust collected at the top of the piece, and then you know you're where you need to be.
Step 4: Making a Jig to Hold Your Table Legs, and Screwing Your Pilot Holes.
Most people will have a metal working vise, when I was growing up my father had one in the garage, when I bought my house there was one left over in the basement. Metal vices have little metal pyramids as gripping pads between the vice clamps. usually this can be removed and you're left with the flat metal of the vice, but you still run the risk of it leaving a mark on your piece since its a metal on wood contact. So when tightening down the clamp you can easily over tighten it and crush the wood piece.
To fix this we're going to make a quick jig to hold our table legs in the vice, that will distribute the clamping force across a wider surface area
So grab a hunk of 2x4 square it off, connect the corners with a pencil line to find the center point. Stick it in the vice and with a Forstner bit or a Spade bit. The size of the bit only matters in that its large enough to fit the smaller part of your tapered leg, ideally you want something that fits the larger end of your cut down leg, just to make things easier, but not everyone has a 1 1/2" Forstner but most spade bit kits come with at least a 1" spade that will work just as well.
Once you've cut your hole, take it over to your miter saw and slice it in half, wrap each half around your table leg, and place it in the vice, line up your drill bit in the center and drill out your holes.
I did my drilling from the side, because its easier to photograph, but you can easily do it from the top down as all.
Step 5: Re-threading Your Cut Down Table Leg.
Once all your legs are drilled, place your threaded screws back into the vice, remember to line up your damaged screw threads in the same spot as they were last time. This will actually help hold them in place since it gives the vice something to hold onto rather then stripping out new threads.
After you've established how much thread to put in the vice, that will in the end leave exposed out the top of your table leg, grab a piece of tape and mark the vice, that way you can align all your threads in the same spot, consistency is really important when doing things like this, so it pays to take the extra step to make sure it all lines up in the end.
Now just take your table leg, and righty tighty it onto the exposed coarse screw thread. You can do this by hand, but once you get down deep its going to get tough and its going to give your forearms a work out. So to make this easier and if you have a medium sized bar clamp laying around. Take it and tighten it down to your table leg, give it a really good twist, dont worry it shouldnt damage your leg, but if want you can use the same jig that we used to hold it into the vice here as well, and give it a turn pushing down on the extended end of the clamp. The length of the clamp will significantly reduce the amount of force you need to exert to thread in the mounting screws.
Hope this helped you, and gave you a few tricks to carry on into other projects down the road.