Black Tar and How To Remove - Help Please!

[withnail]

I noticed today that one of my smaller pipes (called a "10 Minute Pipe" as it takes about 10 minutes to smoke a bowl full) has a slight build up of a black tar like substance near the top of the bowl. It feel similar to bitumen (the thick black stuff you would use to seal a garage or flat roof if it is called something else in the USA) and has a bright shine to it.
I wonder, what causes it and how do I best go about removing it? It isn't something I have ever noticed on my other pipes. Any advice would be very welcome - thanks.

 

[olderthandirt]

Inside the bowl, near the top, not on the rim correct?
I've only had this occur in my cobs. I scrap it out with my knife.

 

[withnail]

Correct - Just below the rim on the inside of the bowl. Mainly on the stem side of the bowl which might have something to do with it as I tend to let my pipes droop down a little when smoking.

 

[ejames]

My theory is it is the early stages of cake build up. Since that area does not stay hot for long it doesn't get "cooked" long enough for to to form a good hard cake.

 

[withnail]

Thanks ejames - it is a fairly new pipe and I do tend to under rather than over fill so the top of the bowl doesn't get any heat for long. Would you leave or remove it?

 

[jchaplick]

+1
ejames
I would wipe it out fter everysmoke, so that only the hard stuff stays and you get rid of the gook