I have a couple of dial locks – a La Gard, and an S&G 6730 mounted on a timber block (shown below). What follows is based around the S&G, but applies to others also. Just to be accurate here, I have included a vernier scale to graph the right and left contact points. Because the protrusion of the fixed marker on the dial (bottom LH picture) made it difficult to stick the vernier scale on, I have 3D printed something to make it easier. It just helps with accuracy.
I am using a printout from P-Point that I put together, to graph the right and left contact points (CP).
So… to the guts of what I want to say. Everyone here wants an easy result such as shown in the All Wheels Left (AWL) graph below. However, many times that might not happen. This plot shows the Right and Left contact points. It is very clear where the bumps are. And because I set the lock to the code: 20-40-60, it is obvious that this is wheel 3. A dream graph!
But what about other times, and you get… nothing!
Here below, I know what the code is (I set it to 40-45-50). And looking at the Right contact point only, which is commonly done, I get this. I graphed the lot, to be complete, even though perhaps I only needed to graph around the known code. (Apologies for the missing line at 47. The printer head probably needs cleaning.)
And if you do wheel isolation, and put wheels 1&2 arbitrarily at, say, 40, and graph W3 - because W3 usually shows first - I get this (below). Which shows… nothing!
I hope you can understand the code on the top LH corner. Again, I didn’t need to show all the graph. But I did it anyway.
So, and here is the kicker, look at the AWL graph again (above), look for the lowest reading. Here, it is at 80. Parking W1&2 right at 80, and graphing for W3 left:
Now, Blind Fredy can spot it. And there is no need for a High-Low test as you are directly checking for W3.
Then, parking W1 left on 80 again, and W3 left on 49.5 brings up this. And again, because I am doing Wheel-Isolation, it is obvious that it is W2:
Then of course, I brute force the last unknown W1. Piece of cake!
So, to summarise what I am driving at here… Why bother with an AWL graph and then a High-Low test? Take two minutes and do an AWL in steps of 10 (no graph needed). Don’t just arbitrarily park wheels anywhere. It might work. But it might not. Look for the lowest value. Park W1&2 here, and look for a reading on W3. The drop should be very clear.
It may not work every time, but it can help on most basic locks.
I should add that here I am looking for W3, which commonly shows first. If W1 or 2 shadows W3, I would still park two wheels on the lowest point and look at each wheel in turn.
Unfortunately, my locks always show W3 first, so I am unable to duplicate this.
I repeat, I am new to this. All input would be appreciated.
Cheers,
Ralph
(Australia)
