How does one block a hat and who has a 7 5/8 fedora block ?

[Art Fawcett]

Fedora, sorry I'm late getting this post off. I should have done it last night but my new site wasin transition ALL night. So, here is my bleary eyed mea culpa
I went in early on Sunday because what we had discussed was contray to what i had experienced. As it turns out, I measured 11 blocks, 5- 7 1/2 and 6 -7 3/8. With the 7 1.2s the circumference ranged from 23 5/8 to 24 1/4!!! I also measure a shaped block "C" crown and it was to my surprise 24". That and the finding in one of my "Hat Life's" 1943 that it makes a statement almost word for word with your statement. I have learned more than one thing here, Hats off to you sir!!
Here is the confusing thing though. I am 23 1/8 inches in circumference. Using the "C" crown block ( it's in the midst of being made) I have shaped a hat, set the band line, formed the brim, and for kicks, without sewing the leather in, set in a 7 3/8 leather. Then I removed it from the flange and woohoo, it fits. But, according to your block formula, it can't. It should be flopping on my ears. If I had used one of the narrower blocks then I can come up with a good scenario as to how it could fit. But the circumference on the block I used was 24" exactly. Now, I can allow that the hat might be just a tad big, but not very much. So, if I allow that it is 1/8 too large, I still have used 3/4 inch for the leather, which is impossible. See my dilema? It doesn't make sense. This is where the science and the practical would seem to colide. When measuring the finished hat with a hat sizer it says a touch more than 7 3/8. I may never get a grip on this one. Something is off somewhere!!!

 

[Fedora]

That is confusing. I don't know. Whenever I was modifying my very first block, I did not know for sure how much to allow for the sweatband. I grabbed a 7 3/8 block that I had just bought and measured the circumference. It was 23 and 5 1/16. I looked to the online hat sizing charts and got a big surprise. So much variation in circumference of head size for a given hat size. I even brought this up at COW. I mean, pi is pi-right? It still does not make sense to me. Anyways, I used the 7 3/8 blocks differential, i.e a 23 inch head is a 7 3/8 hat, and the 7 3/8 block that I had was 23 5 1/16. When I made my block 5/16 larger than my head circumference, it worked. That is all that I was going by. Your experience is mystifying. I know that the thickness of the sweatband plays a big part in the equation. I have seen thick bands and thin bands. If a hatter used a particularly thick band, then the block would have to reflect this. Otherwise the hat would be a little too small. Contrawise, if the hatter used thin bands, the block would also have to reflect this. Of course, we are talking mms. here and it may not make a difference. I am grabbing at straw. I just really don't know. regards, Fedora