Is This C18 Regummed?

As Brian pointed out, there are exceptions to the rule.
Typically US stamps had gum breakers to reduce curling.

http://www.1847usa.com/GumBreakers.htm

However, for some foreign issues, the "curling test" is beneficial for determining watermark direction. For a specialized collector that can make a big difference. Here's an example for DDR stamps:

https://goscf.com/t/27771&SearchTerms=curl

Curling is probably a good rule of thumb, but I don't think it should be used as a definitive test. It certainly isn't ironclad for all stamps.

Dan

Brian,
Understood and agreed with your opinion on misinformation. Of course I am not so sure that it applies in this case unless you are saying that the information that will be presented in the APS summer seminars is incorrect.

But question for you. Stampcrow has two of the same stamp. He has put both in his palm and we can probably assume that the ambient environmental conditions, and his hand temperature, are close enough to call the same. This effectively makes the test conditions relative. So how would you explain that one stamp curls and the other one does not?
don

Good morning everyone. 51 Studebaker has asked me to comment in this thread. I am happy to do so. First, let me say that the C18 originally shown to start the thread by Stampcrow is perfectly OK. What he interprets as "brushing" is actually normal (although excessive) natural flat plate gum creases.

Brian makes a lot of excellent points in his arguments about the accuracy of using "curling" as a "test" for regumming. "Test" is probably too strong of a word, because the result of any "test" should be a defining result, and in this case, it is not. I will explain. The heat from a palm of the hand will usually cause a stamp with fake gum to start to curl up. Note the operative word is "usually". Now what makes that happen? I don't know, but my guess is that it is caused by the thickness of the gum versus OG, yet that would seem to make it harder for the stamp to curl, so frankly, I do not know the "why", but only that, in fact, it does happen. And if you place the stamp gum side up in your palm and then put your hand close to a light source (throwing off MORE heat), it will REALLY curl up! So, bottom line, it is a definite repeatable event that a RG stamp MAY curl up if placed in the palm of your hand gum side up.

However, in no way would I consider this the "final" or "best" test for determining if a stamp is RG or OG. Indeed, the BEST tests occur by examining the perf tips and holes with good magnification (I use 15x, and I recommend at least 10x, but not more than 20x for this work) to see if you can detect any gum spillage in the perf holes or any gum adhering to the fibers on the perf tips. Since perforating occurs AFTER gumming, it is not possible for an OG stamp to have any gum adhering to the perf tips, nor in the holes. As has been pointed out by others, the perf tips can be filed by the regummer to remove the gum on the fibers yet this will rarely fool an expertizer as the file marks give away this deceptive attempt. There is a method of regumming however that can result in the perf tips looking natural and that is to imbed the stamp, face down, in soft clay enough so the perf tips are imbedded but not, of course, the back of the stamp, which is regummed, dried, then removed from the clay bed. The tips will have the fibers intact, making detection of the regumming very difficult.

It also helps greatly to be able to recognize OG based on the gum typically found on that issue, so building a reference collection is important as the gum on a low value of a series of stamps will be the same as used on high values (a 1c Columbian has the same gum(s) as on a $5.00, etc).

I hope these few comments help. I note many interesting discussions here and am pleased that they are taking place and I just wish I had more time to participate here. As time goes on, the old VSC chat board has less and less substantive discussions on these kinds of topics as does PhilaMercury which, of course, is 95% postal history as it's Administrator wishes, so a good general-purpose discussion board is most welcome.

Further help and/or information on this subject can be found in this instructional tutorial (although I don't see anything about the curling "test"!

http://www.hgitner.com/regummed-stamps.html

I wish I knew for certain. I don't know enough about the BEP's gumming process to speak intelligently about it.

I will, however, speculate out-loud whether their process for applying gum was consistent.

Questions worth asking ...

- Does the size of the stamp affect the effectiveness of gum breaks?
* I think it does!

- Did BEP ever apply multiple layers of gum to a sheet of stamps?

- Is there such a thing as a "re-entry" during the gumming process?

- If multiple layers of gum were applied to a stamp, is it possible that the gum-breaks were gummed over?


If all of the above is true, then Stampcrow's stamp would almost certainly curl much easier than a stamp with a single layer of gum with gum breaks.

I'd be interested in knowing more ...

Brian

This is a really interesting thread. Thanks to everyone! The stamp I pictured in my post definitely curled in my palm. But, the perf tips are as clean looking as the rest of the margin.

I have both my copies sitting side by side, out of there mounts, on the table. The stamp in question has more curl just sitting than the other stamp. I wonder if it isn't just a difference in the original application or batch of gum?

Don,

I meant no offense, nor did I mean to try to shut you down or discredit you. You have given great input on classic US stamps and welcome your continued input! Forgive me for my reaction as I got a little wound up when Stampcrow concluded that his stamp was regummed - I felt like the issue needed to be addressed.

As for the APS seminar, I am not familiar with what information will be presented. The questions and comments I asked in my previous posts are just a few that should be examined before concluding anything about the validity of "curling", or any other type of non-scientific tests. I live and breathe the "scientific method" in a foundry metallurgical lab, and believe that process can be applied here.

Bill,

Thank you so much for your participation in SCF! I really wish more experts would get involved in these types of forums. It is genuinely appreciated!

Brian Riley

Brian,
Agreed, and I would also add that a stamp would not have to be regummed to cause an uneven distribution of the gum. It could be that the stamp in question was sweated or had something else that changed the gum distribution 40 or 50 years ago. I would assume that it would be very difficult to now, many decades later, see this kind of thing once the gum has crackled with age. Heck it could be that some gum was slightly thinned many years ago by barely sticking to something, leaving slightly less gum on part of the stamp.

And of course there could a variety production/process issues that might also contribute to a one stamp curling while another does not. But since learning about the 'hand' test I have had the opportunity to use it 9-10 times. Being so quick and easy to do, I use it as a way to determine if I am going to burn additional time in a much closer analysis of the stamp.
don


Edit: Oops, you slipped in before I got this posted. No problems, an honest and respectful exchange is always welcome!

Brian,

Thank you for your comments. The info on the seminar referred to by Don earlier can be found here;

http://stamps.org/Summer-Seminar;

And scroll down to "Four Day Courses". It was quickly "sold out". The class can accommodate 24 people. Maybe they will run it again a year or two from now if they build up a "waiting list".

Part of the course is to give students "hand-outs" which can be either printed articles or articles assembled on a disk (we will have both). And one of the articles we will hand out, on regumming, will be the one from Henry Gitner's website that I put the link to here in my earlier post. I have been writing a series of articles for handouts and Don has been helping by proof-reading, adding graphics, etc. Some of the articles are already on my website (http://www.stampexpertizing.com/ - which by the way was designed by DON! so anyone wishing to obtain a high quality website at a reasonable price, contact Don!). Some of the other articles will not go up on the website until after the students at the Summer Seminar receive them, but eventually they will all be there. Many interesting and (hopefully!) helpful articles can be found on the website.

The gum on my C18 is like that too:

Mike33 have you done the curl test, mentioned in this thread, on that stamp?

That statement is also false on many double line watermark W-F stamps, I've seen plenty that are pretty obvious. Often on the inexpensive varieties that no one would possibly regum.

The curl test for regums is a total curl, literally into a roll not just an arc. Any gummed stamp will do an arc. Forty years ago it worked pretty well for the older regums out there, but I don't know if it is still valid today.

I did and got a slight curl

Thanks Mike33