Details of a correct High-Low test

[rohare]

Hi guys. This is my first post on keypicking (aside from a quick introduction) but I've read up on darn near everything in the combination locks forum. I'm currently working on an Ilco-Unican 673000 for the second time with a number that was set by my wife. I found a number (L57) and did a high-low test to determine that it was the number for wheel 3. I confirmed that with my wife so I know it's correct. Next I found R88 and confirmed that this is also one of the numbers, but did not inquire as to which number in the sequence because I wanted to find out for myself. When I began the high-low test on this one, a question occurred to me and has been nagging me ever since and I'm now questioning my understanding of what a high-low test is doing inside the lock.

In my *first* high-low I ran the following sequences:
High Tests:
R67-L57-L57
L57-R67-L57
L57-L57-R67
Low Tests:
R47-L57-L57
L57-R47-L57
L57-L57-R47

During these tests I looked for a widening signature and this worked perfectly to correctly show me that L57 belonged to wheel 3.

My understanding is that you test two wheels with the good number and look at the results of the bad number because if you only tested the good number on one wheel at a time you might not ever see a good indication if the fence is resting on one of the wheels with a wrong number.

So, as I progressed along I knew that my combination was ?-?-L57 and I knew that one of the two remaining wheels was R88. I set about doing a high-low test like so:
R88-L98-L57
L98-R88-L57
Low Tests:
R88-L78-L57
L78-R88-L57

In this scenario shouldn't I be looking for a *narrowing* signature? If I understand the workings of a lock correctly, moving two wheels into correct positions should narrow the signature whereas if there are two wheels on wrong numbers and one on a correct number (wheel 3 on L57) the signature should be wider. I've never seen this specific issue come up on any of the other forum posts and just wanted to be sure before I throw away a bunch of time. Also, if this assumption is wrong, I'd really like to understand why it's wrong because it really, really seems right.

Thanks a bunch!

[gfunx]

What you are saying is correct. I think you may just be getting a little confused as you are looking at it differently (but correctly) for the second wheel you are testing.

When you are testing your first number (in your case testing 57), you have to look for the wider reading as you are testing three wheels and will have two of the three tests giving a narrow reading. The wide reading is the only one you can determine is different.

When you are figuring out the second wheel (in your case 88) you can really look at either way since you are only testing two wheels. You only have two options that you are checking out -
1. you are testing (going high/low with) the non indicating/gated wheel - you are going to have a narrow reading
2. you are testing (going high/low with) the indicating/gated wheel - you are going to have a wide reading
It doesn't matter which way you look at it, its the same thing. I imagine that most people continue to look for the widening signature for consistency, as its what we need to do when we are checking for all three wheels when we are working on the first number.

Hopefully that makes sense. If it doesn't, let me know and I can draw some pictures that should make it clearer. Or perhaps someone else will come along and explain it better.

[Oldfast]

....Or perhaps someone else will come along and explain it better.

Nope, not really You summed it up pretty good I think.

.....and I'm now questioning my understanding of what a high-low test is doing inside the lock.

Sounds to me like you have a very good understanding. Personally, I think you just need
confirmation from a couple of us for you to begin trusting what you already know.

In the simplest of terms:
When a gate is aligned under the fence, you'll have a 'good indication' (narrowing CA)
With hi/low testing, we're simply bringing each wheel, one at a time, AWAY from that
good indication. Naturally, when the gate is brought out from underneath the fence,
the good indication goes away (widening CA), and we can tag the gate to a wheel.

So far, I've told you nothing at all that you don't already know. lol

By the way, 2 points for correct rotations on all your tests so far!
I struggled with that for a while. You're already ahead of the game.

....If I understand the workings of a lock correctly, moving two wheels into correct positions should narrow the signature
whereas if there are two wheels on wrong numbers and one on a correct number (wheel 3 on L57) the signature should be wider.

2 out of 3 gates under the fence should give you a reading that is either equal to OR (more likely) better than
the reading you had when you found your first gate. Regardless, your hi/low testing to determine if 88 is on
w1 or w2 is going to be absolutely the same as when you tested 57. You're going to throw wheels 1 & 2, one
at a time away from your good indication at 88. When the good indication goes away, you know you just
moved the gate out from under the fence. Bottom line, you're still looking for the good reading to go bad.

That being said, hi/low testing is not always definitive! Sometimes it's inconclusive. Other times completely misleading.
Finding a gate is sometimes the easiest part. Tagging it to a wheel can sometimes be a bit of a cluster fuck. The more
tools we have for this the better. Definitely continue with hi/low testing... but I'd suggest isolating wheels as well.

In other words, run ONLY w2 through the area in question (88). If the gate shows up....
it's absolute. You will KNOW it belongs to w2 because that was the ONLY wheel you were moving.
If you want, I'll take you through it turn by turn. But I won't get that wordy unless you tell me too. lol

Also, you might try throwing/testing the wheels in the opposite order in which you did it. Test w3, then 2, then 1.
This is the order in which they pick each other up anyway. You'll find it saves you time and quite a few of rotations.

Just for fun, hehee. Your final gate will be somewhere between zero and 31. Mmmmmmm..... 19?..... 24!?.... lol

[rohare]

Thanks for the encouragement guys. I really appreciate it but you may feel differently by the time you finish reading this post. So I did the High-Low test on R88 as described above and found a VERY clear widening of the contact area when testing wheel 1. From 8.5 to 9.25 on the high test and from 8.25 to 9.5 on the Low test. In other words, when I test the high number (L98) and low number (L78) on w1 the contact area widens. This should suggest that w1 has the number R88. I was suspicious of a right-oriented number on wheel 1 (remember, I'd already confirmed that 88 was a number so I knew it wasn't just that I needed to translate it to the opposite-oriented number) so i about to ask my wife to confirm that 88 was the third number when I suddenly realized my mistake. I had reversed the sequence of wheel and numbers! I was acting like w3 was the third number dialed and w1 was the first number dialed! Now I have to wear a dunce cap for a few hours and re-work most of my readings... Live and learn.

[Oldfast]

Ah yes... a very common and easy visualization error to make. Betcha won't do that again, lol.