My Old Kiusalas Gauge

I recently acquired a hoard of mint, unsorted, and unpicked Washington-Franklin.

My usual procedure is to sort them by perforation using a Kiusalas gauge. I break the perforation stacks into two groups:

• Matched the gauge as expected


• didn't match

Now that "Matched as expected" criteria is kinda funny. I can only say that after looking at thousands of WFs, you get a feel for what the perfs should look like on the gauge. Historically I have found that many of the mint stamps that make it into my "didn't match" pile are altered -- reperfs, perfs added, etc...

Not long ago, I got a fancy "Sonic Precision Imagery Labs Precision US Specialty Multi-Gauge", and decided to give it a try -- normally I use an old aluminum Kiusalas gauge or a digital gauge with my microscope.

After about half an hour, I had many more "didn't match" stamps than I expected -- including several that are not normally faked. After carefully comparing my Multi-Gauge and my old aluminum Kiusalas gauge, I found they don't quite match. It's not much, but it was enough for me to put several stamps in the wrong pile!

Interesting...

I wonder which is closer to the "precise" Kiusalas standard.

I should have mentioned that I measured them with a glass scale graduated to 1/10 of a mm. The old aluminum one measures correctly.

BTW, A buddy let me measure his version 5.0 Sonic gauge, and it is off as well but not by nearly as much.

Thank you, that explains why my Multi-Gauge makes no sense!!

I would put my money on the old aluminum one every day! Especially if it seems to 'work' - lots of stamps in a pile that fit as expected, with a few that don't.

Apparently, I'm not the only one who has had trouble with this...

https://www.stampauthentication.com...-genuineness

From the link above, Randy Shoemaker from PSAG writes:

Can you clarify which of your two images was the aluminum gauge? Darker at top with 10-80 above, or the one at bottom with numbers to the right?

The Kiusalas gauge has the 10-80 on the top above the dots instead of on the side.
With regards to the ones that don't gauge 10-80, do they gauge 10-79 or 10-81 instead?

I have the Sonic Imagery gauge with 12 measuring devices. I'll have to check it's accuracy.

That's a very good question... It looks like the 80 & 81 lines on the Sonic seem to match pretty closely to 79 & 80 -- i.e. the Sonic is just about 1mil off on those two lines. Here are a couple pics:

One would think that if you were going to make a precision gauge that you would get the design right. That you would understand that measurements start and end at the centers (or the sides, if that is the requirement) of the dots. the Kiusalas gauge has always been the definitive gauge for this - if you want to make 'another' why screw it up?????

In my opinion 'precision' gauges have limited value for a specialist and even less value for a casual hobbyist.

I do not think that contemporaneous specifications/tolerances are near the resolution of current gauges and digital imaging. Has anyone ever shown what the acceptable perforation tolerances were at the time these stamps were printed? Heck, can anyone even show what the die cut tolerances are for currently produced stamps?

But in the absence of any kind of "what was/wasn't" in tolerance we are now going to try to apply a greater resolution? If the manufacturers or the stamp buying Post Office only cared about a single decimal point perforation tolerance back 'in the day', then today having a gauge with more resolution (two decimal point or more) is simply a solution looking for a problem.
Don

I agree with you, Don. We can measure a perforated stamp out to 'x' number of decimal places, but where does that get us? If we have some of an issue measuring perf 10.04 and more of the issue measuring 10.02, what does that really say? I suppose it could be said they were made at different times (can't even really say that) or that the sheets were perfed on different perfing machines that were set up ever-so-slightly different. Woop-dee-do. I suppose after decades of measuring with such precision, we could find what he range of perforations are for a particular issue. Then if we find that the 10.02 is particularly rare, we may have a WHOLE NEW stamp market and collecting area. I seriously doubt that, but who knows?

I used to use the Kiusalas gauge all the time - it is a good tool for finding reperfs. **IF** you know the gauging of a good stamp in the same issue. Reperfers used to not care (or more likely, were not aware) about whether their reperf jobs ended up with 10-79, 10-80, or 10-81. They used whatever their machine was set at, and that was quite often not right. Beyond the Kiusalas gauge, we are almost quite literally (almost literally????) splitting hairs. Of course, there are other ways to find reperfs.

10-79 (wheel) has been found on flat plate sheet, booklet and coil stamps.
10-80 (wheel) has been found on some flat plate sheet stamps.

10-80 (bar) has been found on rotary press sheet, booklet and coil stamps.
10-81 (bar) has been found on rotary press sheet and coil stamps.

The initial sort into "probably good" and "probably fake" is my main application too. At least for mint examples. Used copies tend to have quite a bit more variation. The only better gauge is a known good stamp in the same series.