When shaping a pipe, I occasionally run into the situation where become I concerned about how close the airway is to the surface of the shank. You can sight down the bore of the airway with a straight edge across the suspected closest area of the shank, but that always leaves me a little uneasy.
I have a cobbled together device using a laser level to project lines on a stummel for marking my drilling and this is a way to use the device to see the path of the airway in the shank.
The device is a Craftsman level which is magnetically attached to some steel plate on the cross member.
I inserted a 5/32” bit in the airway and used the bit as a “sighting bar” to project the path of the airway on the outside of the pipe. This is about 3mm, a little too close to the surface, so this pipe becomes a gift.
DocAitch
"Hettinger, if you stamp 'hand made' on a dog turd, some one will buy it."
-Charles Hollyday, pipe maker, reluctant mentor, and curmudgeon
" Never show an idiot an unfinished pipe!"- same guy
I use a laser level and drill bit in the airway the same as you do for the same reason on bent pipes where I know I'm close. Should have known I wasn't the only one.
From the photo you can see that you can tilt the pipe slightly to the left.
It further depends on how you look at it. 3 mm from the axis of the smoke channel is small and the pipe is only a gift. If 3 mm from the top wall of the smoke channel, then the pipe is still quite alive.
Believe me, I am aware of the effect of tilting. This is hand held for a photo. You get a very good idea of where the airway is when you rotate the pipe slightly.
Note in the photo that the laser beam has width, and that the top of the beam can be aligned with the top of the drill bit shaft, clearly demonstrating the top of the airway.
DocAitch
"Hettinger, if you stamp 'hand made' on a dog turd, some one will buy it."
-Charles Hollyday, pipe maker, reluctant mentor, and curmudgeon
" Never show an idiot an unfinished pipe!"- same guy
DocAitch wrote: ↑Mon Aug 10, 2020 12:05 pm
Note in the photo that the laser beam has width, and that the top of the beam can be aligned with the top of the drill bit shaft, clearly demonstrating the top of the airway.
DocAitch
Aligning the laser beam to the top of the drill is by far the most accurate way to determine the actual distance to the top of the shank.
I like .2” but I just learned that you can use an edible/food safe polymerizing oil- tung or walnut- to coat the inside of the airway to prevent migration of juice to the surface. I will start doing that on this sort of pipe, but still warn the customer and be prepared to exchange the pipe or refund the purchase.
DocAitch
"Hettinger, if you stamp 'hand made' on a dog turd, some one will buy it."
-Charles Hollyday, pipe maker, reluctant mentor, and curmudgeon
" Never show an idiot an unfinished pipe!"- same guy
