I was looking for a mod that allows me to wear a helm but not have it displayed on my character, so that her hair will still show.
I found a few, but all of them seem to have to some issues/cons.

So I am wondering if anybody knows of a mod for hiding helms (and possibly other equipment) that actually works as one would hope, by letting you hide your helm and keep all your stats.

The one that appears to be most widely used is Kafeis' Circlets, but this one requires that you buy a circlet which contains all the same stats as your helm.
I don't beleive it will work with non-vanilla equipment. Actually, the author says that he expects people will mod their personal circlet to the exact stats they need by using the CS.
It also compromises either the tail or the amulet slot.

A couple of others I found work similarly, but they replicate all the vanilla helms as a ring. So same as above, except they compromise one of the ring slots.

The most promising one I found is called HideHelms, but sadly the trick it uses doesn't work.
What it does is provide a custom dummy helm that is not assigned to any equipment slot. In game, a script copies all the stats from your real helm, unequips and removes it from your inventory and repaces it with the dummy.
Since the dummy is not assigned to any slot, when it is equipped it appears to be hidden. Very clever. Sadly incorrect.
Problem with this mod is that the game doesn't recognize the stats for an item that is not equipped in one of the correct slots. So you might as well just be taking your helmet off.

Seems to me that it might not be technically feasible to make this concept work correctly.
Save finding a mod that actually works, I've been brainstorming how I might be able to make it work and there is two possibilities that I can think of.
1. 'hijack' another equipment slot using a dummy to clone the hijacked item, then combine the helms stats into the dummy.
EG. if I hijacked the ring slot, the dummy would copy whatever ring you are already wearing, then add your helms stats.
Unlike the above mentioned mods, the ring stats would not be lost.
2. Use NifSE to actually change the mesh that your helm uses, to the mesh that your hair uses. I'm not actually sure if NifSE offers the right functionality to make this work.
If it does work, I think this might work for 3rd party hairs like ren's, but I'm not sure about the vanilla hairs.
OBSE has some functions for copying the models, but hair type and helm type are incompatible.

So if anyone knows of a mod that actually works or has any suggestions of how I could make it work, I'd love to hear.

Thanks
Gaticus Archimedes Windrider

Maybe http://www.tesnexus.com/downloads/file.php?id=21002?

Never test it myself, but from what I read, it might do what ya seek?

I think that is close, except it doesn't actually let you hide an equipped item, just replace it's appearance with another item.
Unfortunately you can't replace with hair (which is really the main thing I want), or no mesh (such as to hide a cape).

You obviously play on PC... so, use Wrye Bash, and set 'tweak assorted' to allow unlimited rings/amulets. have your helm converted to use on of those slots, and, you get the stats. However, your hair will clip with the helm.

I would assume that HideHelms requires OBSE? Are you running OBSE??

Another option might be the http://www.tesnexus.com/downloads/file.php?id=10674 meshes by Scanti. these combine meshes to open up new slots. If you use Slof's Better Beasts you are already using the Merged Teeth mesh for Khajiits and Argonians but that still leaves the Merged Mouth mesh.

I would have to test before I know, but my assumption is that bash is using the hidden slots for the rings.
On further investigation of the problem with HideHelms, it seems that any item placed in an unknown slot will not contribute to the PC's armor rating.
Everything else seems to work, except AR.


If I understand, I would copy the hair mesh into the teeth or mouth slot, then I could use the hair slot to equip the invisible helm instead of an unknown slot?
Is this what you mean? That could work if I can do that from script. I would need to make an invisible/full alpha helmet mesh I figure...
That would solve several issues with the hidden slot method.

By default there is upper & lower teeth slots and mouth & tongue slots (4 slots total, all used). These meshes combine eg. mouth and tongue thus freeing up slots for what you want (2 used slots, 2 free slots). The change has to be defined in the race records. Scripting I know nothing about. All I know is these meshes free up two slots which you can use for anything you like.

http://www.tesnexus.com/downloads/file.php?id=16460

That is what I'm looking for, except that mod doesn't work
Neither does Hide Helms v2.

It puts the hidden helm in an unknown equipment slot, which does not contribute to the PC's armor rating.
Because the hidden helm is also made to be a quest item, it doesn't contribute to encumbrance either. Although I have already fixed that part.
I think you still get the enchantments though.

For now, I am going to make the hidden helm use the tail slot. It just means the mod will not work for beast races.
I'm trying to fix that mod by adding the missing AR to the player as an item enchantment so a hidden slot could still be used, but I can't seem to get obse's magic effects functions to work.

Then there is still an issue with item durability. Since the actual helm is not equipped, it never takes damage.
I haven't tested yet, but I don't expect the hidden helm will take damage either if it's not in an armor slot.
Even if it does, I think the amount of damage an item takes depends on what slot it's in.
Seems to me, oblivion applies damage to durability based on where an opponent strikes you.
If they are always hitting your hands, then your guantlets will wear down faster.
If the hidden helm is using the tail slot, it's not going to take nearly as much damage as if it were in the helm slot.
So I would need to find a way to calculate the actual durability so the helm can be updated when it's unhidden.
I know I can detect a strike, but I'm not sure how to detect where a strike landed.

wetblanket's suggestion would resolve all those issues, but I haven't found a way to set the facegen meshes from script yet.

PS.
I just revised Hide Helms so that it actually works now.
By using the tail slot and removing the quest item flag it now correctly contributes to AR and encumbrance.
Caveat is that it uses the tail slot, so it won't work for beast races.
I've also fixed other minor problems with the toggle functionality.
There is still the durability issue that i mentioned above.

Since a helm is not automatically unequipped when it is down to zero health, like a weapon or shield, you have the option of using a wig as a helm. I.e. find a hairstyle you like and wear it as a helm (with enchantments, defense etc. applied). The limitation is that a wig won't conform to face adjustments, so extreme head shapes are a problem, but a wig can be animated (rigged to more than just the head bone) so longer styles are a viable option.

I can do that from the CS if I were only doing it for me, but I'd like to find a dynamic solution that can work as a distributable mod and will support whatever hair the player is wearing.

Edit:
I would also like to be able to enhance the mod to support other apparel slots, particularly capes, so I think a calculation might be the only way anyhow.

I may even just try to simulate the durability instead of trying to replicate it exactly.
I'm considering something like just decrease durability every hit at a ratio relative to how much AR the item contributes to the players total.
At least this would satisfy my guilt of cheating, however minor

http://www.tesnexus.com/downloads/file.php?id=10832 mod allows wearing a robe over clothing without clipping by making the clothing invisible via OBSE. The script methods used may be of interest to you.