The proof is is the smoking. You will just have to smoke it and see how it does. Truth be told, almost all pipes have some deviation in the drilling. The one notable exception is if you have a Sasquatch. If they aren't perfect, he throws them in the fireplace to chase the Canadian chill from his ancient bones.
LOL not quite - I mean, I really really try to have the height EXACTLY right, but occassionally you wander to the side by a couple mm, and I just don't think that matters much. It's nice if you hit it dead on, but it changes the smoking in no way if you don't. If it's high, it makes the very bottom tough to smoke, and if it's low, it will tend to pack up with junk.
If this is a new/expensive pipe, you might talk to the vendor, but if it's a yard-pipe, just something you bought to smoke while you mow.... I wouldn't worry about it at all.
Sas, what do you mean by exactly right on height? Should the draft hole leave a shallow channel through the chamber or should the bottom of the draft hole and the bottom of the chamber be a smooth transition? I am looking for a relatively solid objective to shoot for.
Ahhhh... that is... up for discussion. The Germans like to see the draft hole right in the middle of the chamber, right at the bottom - an actual hole, like if you drilled under the bowl and then brought the chamber down just to meet that. I suspect this comes from them being used to seeing this in their tradition of clay pipes. To me, this just plugs up as often as not and I don't prefer it. Depends on packing and choice of leaf of course.
Personally, if I had to describe what I shoot for (what DO I shoot for??.... hmmm) I guess I'd say that what I like to see is that the bottom of the airway touches the bottom of the chamber. So the hole is "bottom corner".
In a really bent pipe, I think the idea is to aim the airway at the bottom of the chamber - this will present as slightly oval in the bottom corner, or just up the wall of the pipe in extreme cases. The actual shape of the chamber bit affects this presentation too.
Thanks. I drill the draft hole first then rotate the block to drill the chamber. I place a pipe cleaner in the draft hole so I can feel when the chamber bit breaks though the top of the draft hole. Then I just keep kissing the chamber bit till the proper depth is achieved.
Would a skewer in the to high hole and redrilling it possibly work the one I bought for $50.00 is a no name setup for a 9mm filter and the draft hole is almost 1/8" to 3/16" above the bottom of the bowl, so it leaves an appreciatable amount of tabacco in the bottom of the bowl. The bowl also seems to have been wallered larger on the bottom than the top (at least 1/8" larger on the bottom than the top).