>>851633....OR, he could just smoke his pipe and the natural sugars in the tobacco leaves will form a cake on their own for him as they are smoked. It'll take a little longer and won't be as consistent in places where he has trouble consistently smoking the ashes down to, but it DOES happen.
THIS is why it was recommended for OP to buy a cob pipe when going /out/. It is not necessary to build an ash cake in a cob, as they already smoke cool and dry as it is, but you certainly can if you want to. They're very forgiving care-wise too. If you get it wet just let it dry in the sun for a day and you're good to go, something that cannot be said for briars. Also, replacement cost is $10 vs 60.
As a note on buying corncob pipes, look for ones with a stem that protrudes well into the bowl, like pic related.
In a cob, the stem actually does double duty keeping the hot ashes off of the bottom of the bowl, preventing the ashes from burning through. Lots of sub-$5 cob pipes don't have this, and as a result burn through in just one or two smokes. With the stem going through the bottom of the bowl, a cob pipe can last for years or even decades. That's where your extra $4 goes, and it's worth it.