Why does my dwarf stand idle when having a strange mood?

Solution 1:

There are several possible reasons for this.

1. You don't have enough of the materials

Since you said you have plenty of stone and cloth, I would imagine it's leather that's the problem. You said that you think you have enough because it's only shown for 2 seconds, but the DF wiki says

the mood's primary material will always be shown for only 2 seconds even if more than one is required

so if leather is the primary material, it's possible he still wants more than one piece.

2. The items you have are forbidden

Moody dwarves still respect forbidden items, so if the items are forbidden then the dwarf won't collect them.

3. You have the wrong kind of cloth

If your dwarf is skilled in weaving, he may be fussy enough to demand a particular type of cloth. It is possible you have the wrong kind. When you get the

<dwarf> is taken by a fey mood!

announcement, a weaver dwarf wanting cloth may specifically demand plant cloth, silk cloth or yarn cloth.

When you have the

<dwarf> withdraws from society...

announcement as you do (he sketches pictures instead of making demands), it's possible that he still has a particular kind of cloth in mind, even if his sketches aren't good enough to tell you which one he's drawing.

Source: DF wiki and personal experience of the game.

Solution 2:

He may need more leather? He will only gather the first needed item before gathering the others. So let's say I have a dwarf in strange mood who needs:

• 6 units of leather
• 6 units of cloth
• 6 units of stone

The he will not gather any cloth or stone until he has fulfilled his requirement of leather.

If you aren't sure of the quantities and have dfhack installed, you can use the dfhack command showmood to get exact details.