Since this is my 1st post, I will introduce myself.  I have done a bit of professional theater, but now just volunteer for community theater. I act on stage, as well as work in the scenic shop. But, my main skill is in making special props. I've done professional puppet building in the past, where I have to make the puppet's costume from scratch.

I've taught hat making for youth, using the foam construction techniques I use in puppetry.  These are oversized foam hats that are mostly for costume use.

What prompted me to search for a hat making forum, is that I have an antique opera (collapsible) top hat. The circumference of the hat brim opening is appropriate for the size of my head.  However, the opening is too circular for my head.  So, ideally, I would somehow stretch the opening to be longer front-to-back.

The collapsible opera hat seems to be in its own category from most other hats.  It has a mechanism, which needs a firm base and top attachment.  And indeed, on my hat they are very stiff. Though, I don't know what they are made of.  So, I don't know if the brim would even permit the kind of reshaping that would be needed.

Yet, unless each of these hats were custom-made for the customer, I am sure some method of reshaping would be available.

I realize that this forum is primarily for ladies hats. But, this is the only hat-making forum I have been able to find. Any suggestions about how to proceed with reshaping the hat myself, or where else to look for information?