How long does it take for a cap to form after adding the yeast?

[abefroman]

How long does it take for a cap to form after adding the yeast?

 

[BIGJEFF]

Can you specify what your making, sometimes theres no cap...

 

[closetwine]

Depends on the conditions. I usually see one about 24 hours later,

 

[abefroman]

Can you specify what your making, sometimes theres no cap...

Red zinfandel from juice.

 

[Tom]

you dont have a "cap" but rather "foam". Now this you dont want to "punch" down like wine from fruit.
Depending on a number of things figure 24-36 hours you should see good fermentation.