Improvised Weapons, modified for size and weight... HELP

[Yuric the Bold]

Needless to say things didn't quite go as planned at the ball and my character had to check his weapon for some high brow eatings and drinking.
Then my party decided to sneak away during the dance and investigate the catacombs under the duchal tower we were guests in.

Apparently the catacombs concealed the entrance to a ancient and secret treasure trove of powerful magical items and possibly an artifact.

Without my greatsword my war troll character felt naked; but was able to borrow a puny human equivalent to at least fight with.

We encountered an iron golem.
We destroyed it.
I have decided to wield its severed arm as a greatclub instead of a puny human sized greatsword.

What damage should the severed arm of an iron golem do as a greatclub?!
I do not think that the base damage of a greatclub is truly representative of something of that size and weight...

Thoughts?!

PS Thanks

[Ephemeral_Being]

Complete Warrior has rules for the damage of improvised weapons on page 159.

[Yuric the Bold]

Complete Warrior has rules for the damage of improvised weapons on page 159.

You sir; are awesome. Forgot about that little tidbit in there.

I literally petitioned my DM to let the arm do 3d6 as base damage.
I think the weight and size of a severed golem arm qualifies as a full chest.
Beast mode.