http://www.globaltextiles.com/products/detail/94267/hat-components.html

http://www.globaltextiles.com/tradeleads/detail/060/631680/Sell-hat-accessories.html

But you have to buy hundreds at a time and pay cash up front.

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For just a few hats, buy them from thrift stores and rip them apart.

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You can also use the really stiff interfacings meant for belts and purses.

This post was edited by lazygardens on Mon, Jul 15, 13 at 10:00

Clare,

If you are still looking for the curved plastic insert for hat peak to make your ball caps let me know I have some that I was going to put out on ebay if interested.

i would have started with bleach bottles or milk cartons.

Hi, Did you end up making caps? I also am trying to find brim inserts but its hard to find so i would like to make my own. I know they wholesale them in china. But i would rather make them on my own. Do you have any tips?

Cap making brims/visor boards (capsupplyco.com)

1(866) 957-3366

Walmart: HOMEMAXS 10pcs Baseball Hat Brim Hat Shaper Hat Support Caps Liner Hat DIY Liner