| Author |
 Replies: 37 / Views: 16,498 |
|
Valued Member
United Kingdom
299 Posts |
|
|
|
This evening I discovered on the ruler of my Lighthouse gauge a difference of about 0.5mm for every 4cm (measured with a metrology etalon). Given this error, I kind of doubt the accuracy of its perforations, too.
So, I kindly ask your opinion over what would be the best tool to use, please!
At this point, it looks like I will have to measure again all the stamps in my books once I purchase a most reputable tool available on the market :)
|
|
Send note to Staff
|
|
|
|
|
Pillar Of The Community
United States
4415 Posts |
|
|
I use the Linn's 4 in 1 multi-gauge and no complaints on accuracy, etc. |
Send note to Staff 
|
Al |
| Edited by angore - 01/05/2018 6:54 pm |
|
|
Valued Member
157 Posts |
|
|
I like using the Linn's for measuring perf/diecut size(I found it's the easiest to use). This one is also very useful.  |
|
Send note to Staff
|
|
|
Pillar Of The Community
United States
898 Posts |
|
|
I really recommend the Precision Multi-Gauge shown in the post above.
Even though it says "US Specialty", I find it very helpful for getting the fractional perfs correct.
Also, their guides for rotary vs offset work equally well for some of the troublesome Japanese stamps that were printed both ways as well. (The Tazawa stamps of 1914-1933, "old die" vs "new die", Scott 127-145a). |
|
Send note to Staff
|
|
|
|
Pillar Of The Community
Australia
3282 Posts |
|
|
I have a lighthouse perforation gauge with a 50mm ruler printed on one end of the card. I checked it against other rulers in the house and there's no discernible difference.
Perforation gauges are measured over 20mm so you're looking at a variance of 0.25mm over the 20mm. To what level are you measuring your perforations? Are you collecting issues that require that fine a difference? I'm intrigued!
|
|
Send note to Staff
|
|
|
Valued Member
United Kingdom
299 Posts |
|
|
Bobby De La Rue, it is a matter of principles first of all: if the ruler is not spot on, then how can I be sure about the perforation gauge to be spot on?
On US stamps there is such a huge variation of perforation sizes from one perforating head to another and my feeling is that on many occasions the pins were replaced while still perforating on the same role of prints. |
|
Send note to Staff
|
|
|
Pillar Of The Community
Australia
3282 Posts |
|
|
Thanks aug-stamps - I had no idea of the wide variance in the perforations of US stamps. You learn something new every day!
Is the Lighthouse gauge relatively new? If it is I'm sure they would be interested to know that something is wrong with their product. I agree with you, if the ruler is out the perf. gauges would have to be out too. |
|
Send note to Staff
|
|
|
Moderator
United States
12330 Posts |
|
|
Please do not spend time measuring US stamps; measuring US stamps is one of the least reliable methods of IDing stamps. Become knowledgeable on perforations, watermarks, paper types, and ultimately on the production history of the stamps. If you need to understand a US stamps design size, make and use a template from other stamps (shown here http://www.stampsmarter.com/learnin...methods.html ) A US collector can ID every W/F stamp in his/her collection without ever measuring a stamp design with any ruler or micrometer. Don |
|
Send note to Staff
|
|
|
Valued Member
324 Posts |
|
|
I agree with the US Specialty Gauge shown above for US stamps. Can't speak for international stamps. |
|
Send note to Staff
|
|
|
Pillar Of The Community
United States
8956 Posts |
|
|
Pillar Of The Community
United States
1414 Posts |
|
|
Quote:
Thanks aug-stamps - I had no idea of the wide variance in the perforations of US stamps. You learn something new every day! Not everything posted on the Internet is true. Some things, if learned, will have to be unlearned. In the 1960's Richard Kiusalas demonstrated that US perforations can be reliably measured to the nearest 1/1000 of an inch using his specialty gauge. Perforating machines were built to tight tolerances to insure that perforation pins would cut cleanly and be durable. A known exception was the widely reported "perf 10 on one side" variety resulting from an ad-hoc repair to a perf 11 perforation wheel at a time when printing enough stamps was a challenge in the face of increasing demand. |
|
Send note to Staff
|
|
|
Pillar Of The Community
1375 Posts |
|
|
Two questions about the Kiusalas:
- is it correct that the 10.5-75 is just the same as the "normal" 10.5 that we find on other (accurate) gauges?
- what is the knowledge today about the 11-73: was it really used, and was it exact on Kiusalas' gauge?
|
|
Send note to Staff
|
| Edited by stamperix - 01/08/2018 12:10 pm |
|
|
Valued Member
United States
333 Posts |
|
|
US Specialty Gauge is expensive, at least compared to others. Why is it so popular? Does it have to do with the oddity
of measuring US perfs, set in fractions of an inch, per two centimeters?
When I measure US perfs on the gauges I have, they seldom come out exactly right.
Don
do
|
|
Send note to Staff
|
|
|
Pillar Of The Community
United States
1951 Posts |
|
|
I have several gauges. The Precision Multi-Gauge is my go-to.
Jack Kelley |
|
Send note to Staff
|
|
|
Pillar Of The Community
United States
1414 Posts |
|
|
A perforation gauge is not a measuring device. It is a filtering or grouping aid. Perforations are grouped by how many perforations to the nearest half perforation fit between lines two centimeters apart. Kiusalas reasoned that machinists who made perforating machines used English measurements. Actually, the spacing of perforations is determined to how many equally spaced pins exist on each standard size perforating wheel or the spacing of perforations on a bar perforator. See Larry S. Weiss's article "Perforation Measurement and Scott #544" on the USSS web site: Quote:
The Specialist gauge retains reference to the traditional hole count in a two centimeter length, the system that gives us the familiar perf 8V2, 10, 11, 12, and 12V2 found in the Washington-Franklin head issues. In addition, it recognizes that in some cases the hole centerline-to-centerline spacing is not alike on all stamps of the same nominal gauge. For example, those called perf 10 in our catalogs for both flat plate sheet and rotary press coil Washington-Franklin head issues are spaced differently. The flat plate-printed stamps have perforations spaced at about 0.079 inch (that is 79 thousandths of an inch) between centerlines of the holes, while the rotary press stamp perf holes are generally spaced about 0.080 inch apart. The Kiusalas Specialist gauge labels these 10-79 and 10-80, providing separate rows of comparison holes.
The Bureau of Engraving and Printing, when contracting for perforating equipment, did not use the two centimeter philatelic system for the perforation spacing. They did not use any system that specifies the number of holes in a certain length. Instead, the number of pins in the perf wheels were controlled, using one particular wheel diameter for all the flat plate perforator work (Leavy, 1918). Wheel diameter for the rotary press perforators were different than that for the flat plate work. The link below is where the article is located, but the web site will require a search to reach the article. Joining the United States Stamp Society would be an excellent investment in education and the future of philately. http://75.101.135.193/PDF/Specialist_680/27555.pdf |
|
Send note to Staff
|
|
|
Pillar Of The Community
Australia
3282 Posts |
|
|
Quote:
Not everything posted on the Internet is true. Some things, if learned, will have to be unlearned.
In the 1960's Richard Kiusalas demonstrated that US perforations can be reliably measured to the nearest 1/1000 of an inch using his specialty gauge. Perforating machines were built to tight tolerances to insure that perforation pins would cut cleanly and be durable. A known exception was the widely reported "perf 10 on one side" variety resulting from an ad-hoc repair to a perf 11 perforation wheel at a time when printing enough stamps was a challenge in the face of increasing demand. Thanks cfrphoto  Thousandths of an inch is pretty intense for perforation measurement. From the original post, I was thinking more along the lines of the difference, for example, between 11.1 and 11.8 or something like that. |
|
Send note to Staff
|
|
|
Replies: 37 / Views: 16,498 |
|
Posted 01/05/2018 6:34 pm
