Preparing the "Threaded Bolt"
|While we wait for the paint to dry on the legs, the next step is
to fabricate some "threaded bolts" to screw into one end of each leg (leg
levellers will go into the other end). There are several ways of
doing this depending on the tools you have available.
Regular Bolt - Forget It!
If you get a regular bolt with the hexagonal top, you'll find that
the thread is only 1" long. If you cut off the top and insert this
into a hole in the top of the leg, you'll quickly find that it won't stay
in the hole. The trick is to get a bolt with a thread that is at
least 2" long.
Threaded Steel Rod - Forget It!
Another way is to buy a 3' length of 5/16" steel threaded rod and
cut off 2" chunks of rod. The thread is already there and all you
have to do is round the edges of each end with a file or bench grinder.
However, I've always had difficulty with the start of any thread that I've
cut which can result in a stripped T-nut if you get it wrong - major problems.
Regular Bolt Plus Thread - Not Bad
If you take that 2" bolt with the 1" thread, you could cut a thread
on the rest of the bolt with a 5/16" die - if you had a 5/16" die handy
or you wanted to spend the money to buy the die. After you've cut
the head off the bolt, round the edges of the cut with a file or a bench
grinder. Cut the thread. Make sure you recognize which end
you've cut and which end is the original (sounds kind of dumb but this
is important). Here's the tools you'll need and this is what the
process looks like.
It takes a bit of time, lots of patience, a mound of steel crumbs (make
sure you wear safety glasses), a bit messy, but it does the job.
But there's got to be an easier way to do this!
Carriage Bolt - Best!
If you look at a "carriage bolt" - those bolts with the round head
(readily available at your local hardware store), you'll find that the
thread extends well beyond that 1". I like to use a 2½" carriage
bolt. Use your hacksaw to cut off a 2" piece and round the edges
of the cut with a file or a bench grinder. Make sure you recognize
which end you've cut and which end is the original (sounds kind of dumb
but this is important).
You might be tempted to try and get more than one 2"
piece out of each bolt. Don't! When you cut off that 2" piece,
you probably hacked apart the thread. If you try to screw that into
the T-nut on your module, you'll quickly mangle the thread on the T-nut.
Whatever method you use, make enough threaded bolts for
all of the legs you're fabricating. Make sure you identify which
end has been cut with your hacksaw. This is the end that will be
screwed into the wood leg.
So, let's drill some holes.