enjoy the link and TL;dr version
http://www.kumoricon.org/policiesProps and Weapons
A prop is any item that is for display or part of a costume, or a potentially dangerous item, carried or worn by an individual.
No members will be permitted to carry any kind of functional projectile weapon. This includes individuals who possess a weapons permit or concealed weapons permit. Keep them at home. Anyone found in possession of such a weapon will immediately be removed from the convention. Individuals caught in the illegal possession of a functioning projectile weapon will be reported and turned over to the proper authorities. All other items that could be used as a weapon must be peace-tied or peace-bonded.
Obviously harmless props, such as teddy bears, will be waved through. Any other prop deemed safe by the staff may be peace-tied upon review by the staff member. A peace-tie is an indicator attached to your prop which signals to all staff that your item is part of your costume and not unsafe to carry. It also signals that you have agreed to carry your prop safely. This means you will not brandish any prop weapon, engage in any mock fighting, or use your prop in any way which could be seen as unsafe. You will be required to sign an acknowledgement of the requirements of safe-carry.
Peace-bonding will be conducted at the Peace-bonding table next to the Registration area. After hours, please see the Kumoricon Yojimbo Office to obtain a convention-recognized peace-bond. Complete this action before wandering through or around the Convention Space, or you may be required to leave. If you purchased your item at the convention, peace-bonding is required as soon as possible.
All bladed items must be kept in their sheaths at all times in the Convention Space. Weapons should never be waved around in a manner that may be construed as use of the weapon (this is considered brandishing).
Gun replica or other replica projectile weapons should not be pointed at anyone at any time. Replica pistols need to remain in a holster; replica rifles need to be slung.
Brandishing a weapon in the Convention Space, or in nearby spaces such as other public hotel areas or parking lots, may result in immediate removal from the convention. Keep in mind, police will assume all drawn weapons are functional, and will act accordingly. If you are unsure whether your weapon is acceptable in the Convention Space, please ask in the Kumoricon Yojimbo Office or ask at the Info Booth.
Exotic weapons will be dealt with on a case-by-case basis. Do not bring weapons that Kumoricon staff cannot tell are fake from ten feet away.
Certain props are not allowed within the Convention Space. These include, but are not limited to:
Airsoft or projectile weapons
Live (sharp enough to cut) steel
Props wide enough or long enough to inhibit flow of traffic
Replica weapons that do not comply with state or federal law
Paddles (all varieties—including “yaoi” or “yuri” paddles)
Props which impede personal or public safety