It may seem kind of obvious, but what exactly can the mono upgrade be aplied to? Weapons with primitive quality and power weapons are both obvious and adresed in rules, but what about primitive weapons without primitive quality, chain and shock weapons? Rules state that the upgrade can be applied to any close combat weapon however for example chain weapons fluff state that the "teeth" are already monoedged and statwise chainsword is monosword with tearing added on. So what are your thoughts? I play DH for more than 2 years, both as a GM and as player but this is first time this occured to me. If you could also add some logic behind your opinion I would be extreamly grateful.

Since the primary point of adding 'mono-' to a weapon is to remove the Primitive quality, there would be no point to adding it to non-Primitive melee weapons. Like you said, Chain-bladed weapons are already mono-edged, and Shock weapons don't rely principally on the physical weapon, but on the energy it generates. So, no mono on non-Primitive weapons.

On a related subject, one of my players wanted to use a huge hammer as a 'signature' weapon, and wondered if 'mono-' could be applied to a non-edged weapon. I house-ruled that it could, expanding the description to 'mono-edged or equivelant upgrade', taking into account advanced materials like depleted urainium and whatnot to no longer count as Primitive.

AFAIR, Errata says: "Any primitive close combat weapon

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The Mono upgrade may be applied to any melee weapon, but when applied to close-combat weapons that do not use an edge (e.g., hammers, mauls, etc.) it is defi ned differently

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For example, a hammer with the Mono upgrade is defined as having a pneumo-shock enhancement. The in-game effects remain the same."

Since the primary point of adding 'mono-' to a weapon is to remove the Primitive quality, there would be no point to adding it to non-Primitive melee weapons. Like you said, Chain-bladed weapons are already mono-edged, and Shock weapons don't rely principally on the physical weapon, but on the energy it generates. So, no mono on non-Primitive weapons.

Actually you might want to get the upgrade just for the +2 to penetration. Also, I am not so sure that shock weapon relly on their energy, quite a lot of fluff portray (for example) arbitres shock maul as heavy metal club, with the stunning shock regarded as nice perk. (depending on the pattern of course)

Do not take me wrong, my gut call would also be to restrict this, however there is little in the rules to support this (I also have access to black crusade rules and the ruling seems to be the same ie. any melee weapon). Also I kind of like that it may be a way for our arbitres player to extend usefulness of his iconic weapon (shock maul).

AFAIR, Errata says: "Any primitive close combat weapon

Thanks, kind of missed that part of errata (somehow), however I wonder if that is supposed to mean primtive weapon class or primitive weapon quality.

Thanks, kind of missed that part of errata (somehow), however I wonder if that is supposed to mean primtive weapon class or primitive weapon quality.

Based on description of Bolo knife - "Crafted from mono-serrated plexsteel" - primitive melee, but without primitive quality (IH, p.123/124) I would says what Mono apply only to weapon with primitive quality .

Thanks, kind of missed that part of errata (somehow), however I wonder if that is supposed to mean primtive weapon class or primitive weapon quality.

Based on description of Bolo knife - "Crafted from mono-serrated plexsteel" - primitive melee, but without primitive quality (IH, p.123/124) I would says what Mono apply only to weapon with primitive quality .

That's how we interpret the Mono quality. By those rules, the shock maul cannot be given a mono edge.

If your Arbiter wants to boost the effectiveness of his shock maul, he might want to buy a power maul. Basically, it's a variable-setting power weapon that can be tuned to "stun mode" when incapacitating malcontents or cranked to full power for those times when you want to smash a grav-car like a tin can. I found it in the Macharian Handbook (excellent fan-made weapon compilation), but I believe the stats were originally pulled from Ascension. It's not overpowered (less damage than a power sword when used on full charge) and is a very fluff-appropriate weapon (it is most commonly used by high-ranking Arbites Judges).