Invisible, Usable Back Scabbard

This instructable goes out to everyone who, as a child or a not-so-much-of-a-child, stuck a wiffle bat down the back of the shirt and had trouble getting it out (and putting it in in the first place) for use in swordfighting. 
Or anyone who has used an actual back scabbard and found that, wow, you can't take out a long blade, and it's super-hard to put any blade back in!
This could also be useful for LARPing.

Anyway, this 'ible will show you how to build a back scabbard that is much more usable than any other I have ever seen, and can also be invisible.  Some of the ideas came from back scabbards I have seen where only the bottom few inches of the blade are encased, and the handle sits on something to hold it in place (like this).  I said, hey, let's just hold the handle area with a magnet-WAIT A MOMENT.  Let's just hold the whole blade up with two magnets - one at the handle, one further down!

That's the whole basis for this 'ible.  My particular incarnation is invisible also.

There are a number of versions of this which could be made, and I'll try to keep that in mind as I go along.
So, with that in mind:

Materials:
1 Belt per Blade + 1 Belt (2 belts for 1 blade, 3 belts for two blades) (the way I did it, which is certainly not the most stable way it could be done)
I used 2 wide, D-ring belts for over the shoulders.  I would not recommend them, as the D-rings tend to slip a little every time the contraption is used - but being wide did make them comfortable.
I used one wide, elastic-y ladies belt for the waist (really chest) belt.  It worked very well.
Hard Drive Magnets or other strong, flat magnets - 2 per blade
Scrap denim or other tough material.
Strong sewing thread.
A Blade that this is for (in my case, 2 machetes).
One tight t-shirt (for increased stability and comfort)

Tools:
Needle.
Hacksaw and Vice (for dealing with Hard Drive magnets, possibly)
How to get Hard Drive magnets:
https://www.instructables.com/id/Pulling-apart-a-desktop-hard-drive-to-get-rare-ear/

Then, once you have them, you should have one where the face of the magnet is the highest point, and one which has pegs and/or extensions of the base which go past the face of the magnet.  You want only magnets where the flat face of the magnet is farthest out.
Put the pegs of the magnet in a vice, nice and tight, and hit the magnet (gently!) with a hammer.  The peg should pop out.  The legs, on the other hand, must be cut off with a hacksaw.  NOTE:  if you use a hacksaw near a strong magnet, the magnet will end up covered in metal filings, which are sharp and not fun to try to brush off with bare hands.

Put one belt over your shoulder and under the opposite arm.
Put another around your midsection, based on how long your blade is.
Hold your blade where you want it to stick to your back.  Mark the spot on the shoulder-belt, as well as a spot on the midsection-belt.  I recommend having the midsection belt higher than seems necessary - not at the bottom of the blade, but in the middle is fine.  This does not affect how will it stays attached, but allows for more body movement.

I put a safety pin in the belt to mark about there the magnets should go.  It doesn't matter, exactly, as the belts can adjust.

Here is where you must decide what type of system you want - invisible, invisible under one piece of clothing in particular (a trenchcoat or leather jacket, etc), or worn on top of things.
I recommend invisible, as it lets you wear baggy clothing (which looks bad if it has tight belts on top).
I made mine invisible under any standard t-shirt.
I did this in the following way.
Take a magnet.  Put one layer of denim on top of it.  Put one layer of whatever piece of clothing will be worn over on top.  Put blade on top, and see how much force it takes to pull it off.  I only used one piece of denim for the shoulder magnets, and two for the waist magnets.  If you are doing this under a thick coat, you may want no denim.

Pretty much, however much cloth is between the magnet and the blade determines how hard it is to get the blade off your back.  I recommend plenty of strength, as it's not too hard to give it a good pull, but you don't want it falling off your back.

Sew the denim over the magnet and onto the belt.  If it's denim, make sure you double the edge over so it doesn't unravel.  Sew however you want - I did 1.5 stitches forward, half a stitch back.  When my mom showed me to.

Keep trying the belts on as you go to make sure they're where you want them.  Try them on with your blade(s).  Otherwise, what's the point?

My secure/comfortable adaptation works like this:  put on your tight-fitting shirt.  Put on the belts, making sure they are exactly where you want them.  Safety-pin each belt once to the shirt.  Remove the shirt.  Sew the belt to the shirt at the indicated place.  Now, when you put this shirt on (which can be difficult), the belts will be about where you want them, and you just have to fasten them.  Also, it's more comfortable than belts on bare skin.

You're finished!  Tweak it, let me know how you did a better job than I did (trust me, you did).  Figure out exactly what your limits are in terms of what you can do whilst wearing one or two blades.  Be amazed at how easy it is to draw your blade, and how incredibly easy to put it back!  I roll them on my shoulders going both ways - grab the handle and yank it forward to draw, roll the handle over your shoulder to re-holster.  Have fun!  Be careful!