A few items I am trying to figure out...

-The original helmets have the whole front brim cut off from the liners. Is there a reason for this?
Of course there is a square-ish cut out section to give the helmet sight more clearance, but why also cut off the entire front brim, from left to right?

-The steel pot itself has no cut out on the front of the shell?
Only the liner is cut in the front?

-The slots on the ear hinge are centered to where the swivel bail used to be?

Thanks.

The brim was cut off to accommodate the new front plate, and the drop down IR site. I think all that front cutting was due to accommodating for the front IR site.

Given the amount of helmets they most likely setup a jig to cut a bunch of helmets with a bandsaw. That is the best way to ensure consistency across the board.

On mine I used a Serbian pot metal helmet from the eastern bloc. I cut the front to fit the plate. I cut the side but left the swivel piece for the chin strap. I cut out a section towards the back to accommodate the microphone as I mis gauged the angle to drill things in to the ear flap.

I used a Dremel heavy duty cut off wheel. I went through almost a whole container of the things. I broke several drill bits. Drill bits will not work due to the harder steel. I also cut out for the camera by doing x cuts for the screw holes and an access hole to stuff the wires for the backup camera in the helmet camera. I cut slots for the helmet in the back.

as far as centering the cut I just judged where it would be to properly cover my ear.

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The impossible takes a while longer and goes over budget too...

-The slots on the ear hinge are centered to where the swivel bail used to be?

This is tricky,they are centered on the ear hinge but they arent all the same and some have the ear hinge with the bottom tilted forward.Dont cut to wide or too high at first. you can easily trim more off with a Dremel metal wheel, like butter. I made the mistake of cutting mine way too wide because I Used a reference photo that I thought was screen accurate and it wasnt. Many reproduction ear hinges will be different sizes, so make sure your cuts fit the one you have. If I can find the time, I will get pics or measurements of mine. I got the positioning and height just right I think but theres a lot of people here who have even better ones. The best look is Hudsons in the APC I think.

The more important part is make sure the cuts and the ear cup fits, YOU!!!

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The impossible takes a while longer and goes over budget too...

I wouldn't read too much into the liner cuts. They likely just worked quickly and it is faster to lop the whole thing off than make careful cuts to maintain the brim.



The photos of Frost's helmet that recently sold through the 'propstore' shows pretty clear images that the steel was NOT cut (at least not on that one). So based on that, only the liner is cut in the front.

However, modern Terry English sets do feature the steel being cut too. It really is better as you get a lot more room in there. I cut the steel on every helmet I have made and regret nothing.

That's what I am figuring too.
They just removed what was determined to be unneeded material, at the start, to give a more open work space.
I won't be trimming the brim.
It fits snug, makes a nice transition line into the Strike Plate and covers the rough edge of the crimp.

These steps are probably common sense, but here are some photos to go with the thread title.

Getting Started:
Mark the location (I lined the top horizontal slot with the edge of the helmet)
Set the left and right upper end points (just at the bottom of the upper ear piece)
Tape a line, and make the cut (then lightly grind the edges and corners smooth to the touch).
This took one and a half Dremel #456 cut-off wheels.

I have the cut really close to the edge , but the hinge still swings freely, without touching the sides.
I'm going with a helmet cover, so may widen it a little, depending on the fit of the fabric through the gap.

I wish I could see hot TE does his hinges. You might already have thought of this but you could use a grinder to get the texture off of the helmet.

I'm going with a helmet cover, so hopefully won't have to remove much of the cork texture.
I'll send you a photo of the hinge.