Nice helmet! I've seen Doc working long time on it. It's super clean.
When I've seen your last photo, first I thought if your dremmel slipped, but then I saw the bottom - very nice battle damage.
Most people will tell you to fill the helmet with EVA or upholstery foam.
If you want to, I'd advise to go with upholstery foam, it's way softer and more comfortable, and the surface is more rough, so it won't be as slippery.
But I personally use this in my helmet - sorry, not my photos, but Stormies use this often too.
I got the idea from them. I don't know the name of this, but you can find it in all security helmets (the one below is just an example).
Why? Foam isolates, and your head is even warmer than rest of your body. Meaning you'll sweat, there won't be any air circulation. You'll warm up and sweat.
Here, with this strap? You can leave most of the helmet free, the air will flow, and if you have fans inside, it'll be even better.
- Palmer
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