drilling a bent...best options

[timothy thorpe]

I am no stranger to drilling a bent pipe...i have not drilled a bent yet on my lathe. i have on the drill press for 6 years. so i just want to get everyone's methods here....i know there are a few ways of doing it. the last few times i did a 3/4 bent volcano and the airhole was at the top for some reason! ..so whats the best way to drill in order?

thanks

[Sasquatch]

If I'm doing a bent, and I usually am, I usually try to make and stick with a really accurate drawing on the block. Included in this is the airway. I cut the chamber about 3/4 down and get the bowl shape started. So what I do is face the shank, round up the shank if I'm going in that direction (a bulldog I wouldn't, some real fat shapes I wouldn't), and then drill the mortise, and then I just tap the bottom of the mortise with a 5/32" drill.

Then move the block so that the angle of the airway is what it should be, line it all up so that the bit is going where it's supposed to, and drill the airway about 3/4 of the way.


In a very real sense, I have the chamber and the airway now cut as "pilot" holes, and now I need to join em up.

I will switch to a hand drill, judge the depth of the airway, chuck up the airway bit as needed and finish that hole, then I usually run to the drill press and finish the chamber, bringing it to the airway. This takes about 5 minutes all told, and there's surely faster ways, but this guarantees I never miss the bottom corner. Being a little anal about this means I don't throw away promising blocks because of overdrills or misses very often. Like, once a year, and that's usually if I'm drunk.

[wdteipen]

For me, the most important aspect of a bent pipe is that the airway is dead center in the bottom of the mortise. This assures that every bent pipe will pass a pipe cleaner. I'm a stickler about it and won't make or sell a bent pipe that won't. I also don't like airway drill marks in my mortise. There are various techniques that one can employ to accomplish that goal. The most important thing that I do is planning. I draw out the airway and mortise on the side of the block making sure that my airway intersects with the mortise where the mortise is approximately 1/2" long give or take. If the design doesn't allow for at least a 1/2" tenon, there are tricks one can use to get extra length such as adding extensions, rings, and such.

[Sasquatch]

A wide mortise, like 1/2" or more also allows some crazy freedom that way.

I am less of a stickler for that - I'll ramp the airway a bit inside if I have to. I've also built pipes where the airway came out the side of the tenon, but that's extreme.

[timothy thorpe]

wow great thanks! i pretty much do the same..i was just off a bit and was frustrated !!

[Sasquatch]

Clearing chips as you drill is also absolutely crucial. Briar is a little sticky, tends to clump up on the end of the drill bit, and then it will wander all over the place.

[timothy thorpe]

i ether do a 5/16 mortise or 1/4

[Sasquatch]

Well, smarten up!

[wdteipen]

Yep, if you can't get a 1/2" deep mortise with a 5/16" diameter without cutting into the mortise you could changing the diameter of your mortise. If you have to shorten the mortise, you can still get a secure fit if you go with a wider diameter.

[kkendall]

Design airhole and mortise drill lines to cross where the bottom of the mortise will be. This will help to keep the airway centered at the bottom of the mortise


Drill and countersink the mortise



I will then cut a notch in the edge of the mortise before drilling using an end mill the same diameter as my airway drill and then using the endmill, cut the shallow hole in the bottom of the mortise to eliminate drill wander when I switch to a drill bit.


Then drill the airway


Turn the block and drill the tobacco chamber


As you drill the tobacco chamber, check the depth frequently as you get close so you don't go too far. When you are done, the airway is dead-center and tobacco chamber and airway are tangent. Doesn't get any better.

[wmolaw]

Design airhole and mortise drill lines to cross where the bottom of the mortise will be. This will help to keep the airway centered at the bottom of the mortise


Drill and countersink the mortise



I will then cut a notch in the edge of the mortise before drilling using an end mill the same diameter as my airway drill and then using the endmill, cut the shallow hole in the bottom of the mortise to eliminate drill wander when I switch to a drill bit.


Then drill the airway

That was really, really helpful. God, pics are such an assistance! Many of the older briar blocks I have are not squared up on one side so it's tough to draw identifiable lines, but not to tough to square, I guess, or at least sand so I can get good lines drawn!

Thanks again.

[RadDavis]

You don't have to do all of the notching and cutting a shallow hole in the bottom of the mortise if you drill the smoke hole first, then drill the bowl down to it, then chuck it back up a drill your mortise down to the intersection with the smoke hole.

Rad

[wmolaw]

You don't have to do all of the notching and cutting a shallow hole in the bottom of the mortise if you drill the smoke hole first, then drill the bowl down to it, then chuck it back up a drill your mortise down to the intersection with the smoke hole.

Rad

Great point. Thanks!

[wdteipen]

I do it the way Rad describes. I save the mortise for last.

[Sasquatch]

A mortise is like a kind of turtle, right?

[kkendall]

I must be the only one, but it sure works well. I get what I want ... every time.

[wdteipen]

I must be the only one, but it sure works well. I get what I want ... every time.

You're definitely not the only one. I would bet that Rad and I are more in the minority.

[wdteipen]

A mortise is like a kind of turtle, right?

You're doing it wrong as usual.

[RadDavis]

I must be the only one, but it sure works well. I get what I want ... every time.

Me too.

No one's way is the "right way". Everyone does what works for them.

Rad

[Cory]

I do it the way Rad described, unless the angle of the bent allows me to drill in the mortise without a notch (only works on small angle bents). But I don't see anything wrong with the other way, just preference.