3' bore?

[Austin Kliniske]

Soo I found my 18" face plate for my pre 1920s brown and sharp metal lathe that was converted, and I have a few 20" ish wide maybe 36" or so long logs (lathe has a 22" swing 6' bed thats useable space) and i want to bore a pilot hole..I do not see using or making another extension for a forstner bit a smart choice. I know plenty of folks have made large forms atleast 6' tall but the question here is how to bore the pilot hole to start hollowing.

My first thought is to take my gun drill and start a pilot hole with my tailstock then switch to a drill and gun drill and lock the lathe spindle to let the drill do the work, but I also feel there is a better way, anyone have any information to go off of?

Phot of a .5mm wall goblet for fun

 

[Richard Coers]

I suggest you look at boring bars and not drills.

 

[Randy Anderson]

For my initial pilot holes I use a standard 1/2" drill bit in a chuck in the tail stock to get started. I then use a 1/2" auger bit to go fairly deep. You can get them at big box HW stores at different lengths. They come with a threaded point on the end to self feed. I grind the threads off and leave a small point. First time I didn't and it self fed into the center of the log very deep. Almost couldn't get it out. I finish up using Milwaukee Switchblade bits to bore holes big enough to get my boring bar or hollowing tools into. They come in different sizes with replacement blades and quick connect extensions that I stack to go as deep as I need. The initial pilot hole helps keep them centered, mostly anyway. I have a set of them. The largest in the set is 2 9/16"

 

[John Ames]

I grind the threads off and leave a small point.

+1

The long auger bits are the bees’ knees . Very efficient.

Making the hole on the lathe is easiest but in a pinch, I’ve made very deep holes in things by swinging the drill press table out of the way (or removing it) putting the big/long thing I need drilled on a hydraulic lift cart and lifting the item into the auger/drill bit. Just make sure the work piece is well stabilized or locked down to the table and lower the table to clear the chips.

It can be a little sketchy but by going slow and steady it has worked for me…

Safety third…

 

[Bill Alston]

I sometimes use reduced shank Blacksmith's drills to start holes on my lathe. It should not be too difficult to make extensions for a drill like this if needed? Or you could maybe use some like this. I have several but only in small sizes that go through the tailstock.

 

[Dennis Weiner]

To start the hollowing of a deep vessel, I want to remove as much material as possible. I do use extensions and step drill up to a three inch clock forsnter bit. To prevent drill wandering from center, I start with a small center drill then Drill a 1/4" deep with a 3" bit first to have a groove for the bit to sit in so it doesnt wander. I will then proceed to make another 1/4" goove with the next bit say 2-1/4" etc.. repeat until you get to the smallest bit. At this point, you are ready to do your actual step drilling starting with your smallest drill bit . I usually drill at a slow speed 100-300 rpm wood conditions and bit size allowing. This method works. Most of the problems in drilling have been solved.
I have drilled down as much as 18" successfully on my 2436 oneway. The important thing is not stressing your workpiece and equipment. I clear out the shavings about every inch or so. Occasionally, I may use a boring head to extend the hole to 4 or 5" but It cant go very deep without using a Morse taper extension. I finish the rest of the depth with my hollowing systems Jamieson or Clark depending on depth. I've gone safely as much as 25" deep with the Clark. Others have gone further. The Forces at these depths require 2" diameter or greater boring bars to safely accomplish these depths.

 

[Austin Kliniske]

To start the hollowing of a deep vessel, I want to remove as much material as possible. I do use extensions and step drill up to a three inch clock forsnter bit. To prevent drill wandering from center, I start with a small center drill then Drill a 1/4" deep with a 3" bit first to have a groove for the bit to sit in so it doesnt wander. I will then proceed to make another 1/4" goove with the next bit say 2-1/4" etc.. repeat until you get to the smallest bit. At this point, you are ready to do your actual step drilling starting with your smallest drill bit . I usually drill at a slow speed 100-300 rpm wood conditions and bit size allowing.
I have drilled down as much as 18" successfully on my 2436 oneway. The important thing is not stressing your workpiece and equipment. I clear out the shavings about every inch or so. Occasionally, I may use a boring head to extend the hole to 4 or 5" but It cant go very deep without using a Morse taper extension. I finish the rest of the depth with my hollowing systems Jamieson or Clark depending on depth. I've gone safely as much as 25" deep with the Clark. Others have gone further. The Forces at these depths require 2" diameter or greater boring bars to safely accomplish these dept

 

[Terry Brown]

Since you have a machinists lathe, a gun drill should work very nicely. Wet wood requires a substantial air supply. Both in volume and pressure. Once everything is properly setup, you turn it on and let it do the work while you monitor for sound changes that might indicate a pending problem. A note from personal experience. "ALWAYS have the bits' clearance channel facing away from you."

 

[Richard Coers]

+1

The long auger bits are the bees’ knees . Very efficient.

Making the hole on the lathe is easiest but in a pinch, I’ve made very deep holes in things by swinging the drill press table out of the way (or removing it) putting the big/long thing I need drilled on a hydraulic lift cart and lifting the item into the auger/drill bit. Just make sure the work piece is well stabilized or locked down to the table and lower the table to clear the chips.

It can be a little sketchy but by going slow and steady it has worked for me…

Safety third…

I find just the opposite with auger bits in end grain. Curious how you drill a 3' hole with a drill press. Wouldn't you need like an 8' post to fit a 3'+ blank on the floor, 3' travel for the head, and maybe 18" for the head and hydraulic table in starting position? Could you share a picture of your drill press? I don't feel you are the only one falling short of the 3' hole depth requirement.

 

[John Ames]

I don’t think I’ve ever needed to get to 3’ depth… if I did, I’d probably put my drill press on my die lift and elevate the drill press that way…. Let’s hope that need never comes up!

To get to 3-feet, I might look into one of these

Amazon.com

 

[Randy Anderson]

Austin, not sure where you are in your journey for a tool but from experience doing some deep ones I'll just say pay close attention to hole wobble. Take it in stages and try to course correct if you see it beginning to corkscrew out near the end. A little bit of long tool or extension wobble translates into a big corkscrew hole that can be very difficult to deal with when you start hollowing. Your hollowing bar is extended way out and the bounce of the pilot hole makes it a very tough fight to get back to round and true to center. It can be brutal. Been there too many times.