Button Lock Project

Before we start, those of you in the know will  spot a few spelling mistakes on this page I'm sure. One we know of is the use of Seegufux. This is used so we do not upset the manufacture of the well known hospital restrain equipment with a similar sounding name. You can find an example of their products HERE if you have not come across them before, So lets kick thinks off with some observations on the new Seegufux LOCKS (the green ones). According to Seegufux, they are not useable in Seegufux systems manufactured before February 2003 (ed - we didn't know that!). And I was unable to get a good explanation on why this was the case, as the holes are the same diameter. When I contacted the makers, I  just got the answer that the locks would not fit.

Now I'm the happy owner of a Seegufux set from mid 2000, and I have wanted for a long time to upgrade the locks to something more secure than the black ones. I don't know how well known it is, but the black Seegufux locks can be opened without the key, even without a magnet. I don't want to spoil the fun for anyone by telling how. I'm sure that the persistent and innovative fingers will  find out somehow.. ;)

The first solution to this problem was to design some new locks myself. After a few redesigns, the final one worked well and was quite secure. The main flaw with the design is that they can be picked quite easily with a pair of flat screwdrivers, like the mechanical Heetkamp locks. This isn't a problem if the subject is locked down to a bed, since you should be able to prevent access to two screwdrivers in that situation... ;) However, when the locks are used to lock an overall on to a subject or hold a helmet in place, he or she would have plenty of time and free hands to fiddle around with all sorts of stuff to try to pick the locks. Even a small padlock used in this way can be quite easily picked.

So I took a chance and ordered a set of the new style locks, and, as expected the problems stopping them being used with my year 2000 setup were minor.

The base on the new pins is quite a bit bigger than on the old pins.  38x38mm square vs round 24mm. The reason for the square design of the new pins, is to enable you to twist the key on the lock button to open it  and ideally the base should not be able to turn around. So if you can live with sometimes having to support the base of the pin, while opening the lock you are good to go. Apart from one item,  the waist belt. There simply  isn't space for the huge base on the new pin.

Tool time - You can solve this problem with a hacksaw, file and a bit of persistence (the base is made of stainless steel). Alternatively you can manufacture some pins yourself, but this requires that you have access to some metalworking gear, such as a lathe, a mill and a welder. The result of my efforts can be seen on the attached photo, with the original Seegufux pin to the right.

This project requires some knowledge of metalworking, although most of stuff is made from PVC. Also you need access to a mill and a lathe as a minimum. One with a digital readout, makes things so much easier. If you have these, you can most likely decipher my drawings. The locking "thread" is 1mm spring hardened stainless steel, which is available in most hobby stores, the rest is PVC. Pick any colour you like.

When you turn the outer shell, don't drill the 3mm holes, and make the shell a bit longer in both ends 0.1mm, this way you can face the final assembly off in the lathe when it is all put together,

You'll need a holder in order to mill the "inserts", I made one in aluminium, mounted it in the mill.

Mill the 2 x 6mm slots, and drill the 2 x 3mm holes and the centre hole in the mill then the thing is ready for assembly.
Then put the bottom of 6mm drill, or a 6mm rod into the centre hole of the insert, and mount the two springs.
Fit the hole thing with the drill centred in the middle in the outer shell, only press it about 1mm into the outer shell.
Apply some pvc glue, and press the insert all the way into the shell.  DO NOT, I repeat... DO NOT pull out the 6mm drill.
With the drill still in place, put the whole assembly in a drill press, and drill the 2 x 3mm holes. Using this method they will fit perfectly. DO NOT drill them all the way through.
 

At last, place your key (if you can make the lock, you should be capable of making the key) in the lock, and bore out the centre hole with a 6.1mm drill, also here... don't drill all the way through.

Have fun, and sleep tight.. ;)

If you want to contact me for advice use  the following address inserting @ in place of the #

helmetboy#theoriginalinstitute.com

holder required to mill the inserts