Machin Self Adhesive slit types. Why did I bother?

I had this bright idea of helping collectors avoid the eye strain I have been experiencing in trying to distinguish between the types of slit in Machin self adhesive stamps. I thought I would scan an example of each and that would be that. However, it isn't at all obvious but, as you'll discover at the end, it may not matter a great deal anyway, once you have tucked three items from 2009 away.

So, according to the lists I have from dealers, the 1st Large red issues are an ideal example as they come in each of types 1, 2 and 2a and have different security codes so my job is comparatively simple. There is only one source of type 3 that I have seen listed so that is even simpler - the 50p, 1st gold and 2nd blue stamps in the definitive pane in the George V book.

So, here we go:


Type 2 from the Walsall MA12 MFIL books of 4

 That's pretty clearly different from the others, obvious gaps top and bottom.



Type 1 from the Walsall MA12 MBIL Buisness sheets

This is where I have trouble - distinguishing between types 1 and 2a 



Type 2a from DLR MA12 MAIL Counter sheets

 I really struggle to see much difference between the two. The illustrations in dealers' lists do say 'less noticeable' slits but, my goodness, these are so much less noticeable to be almost non-existent.



Type 3 from the Walsall George V prestige book MA10 MPIL

No problems with type 3. The lack of gap at the top and decent gap at the bottom is clear.

I tried zooming in on the images, sharpening them and using greyscale to try and make the differences clearer but it is still one big struggle to tell 1 and 2a apart. I am beginning to wonder whether the list I am using has got it wrong.


Type 1



Type 2a



Tye 2



Type 3

There is definitely something I need to look into further. In the meantime, here are images of two examples of the 2nd Large where the difference is a bit clearer and that should help you a bit. Just watch your eyes with those 1st Large reds!

Type 2a DLR MA12 MAIL from Counter sheets

Type 1 Walsall MA12 MBIL from Business sheets

Again, you have the different printers here and codes too and, so far, there are only three instances where I can find types 1 and 2a listed for otherwise same stamps (codes, printer being the same).

These three are:

2nd blue DLR 2009 MBIL Business sheet

1st gold DLR 2009 MBIL Business sheet

1st Large gold 2009 MAIL Counter sheet

Let's cross our fingers and hope like mad that there are no more. then, quite frankly, it won't really matter whether it's 1 or 2a.