Tip for cheap & dirty way to drill long holes

Re: Over 300 viewers with no response

Arch

>I'm UN-sure of your UN-seen message? Is my orphan tip UN-acknowledged because it's...

UN-workable? UN-needed? UN-interesting? UNclear?

UN-wanted? or... UNWELCOME?

....or were all your responses censored? :)

You said you wanted to annoy us...

Jay in TX (formerly Ohio)

>Arch,

When people annoy me, I zone them out...just ask my wife (n'yuck, n'yuck, n'yuck).

I read it, and thought that it was a sound enough approach. Never needed to drill a long hole (wife prefers brass and porcelain for lamps), but I'll try to remember the tip if I ever do.

Re: For my part, it was unclear.

Al Crandall --NE of Indy--

>I understood that you used your Nova chuck in the headstock to replicate a hollow Jacobs chuck so you could drive a long drill with the headstock. I just wasn't sure how you fastened and supported a 22" long workpiece to the tail stock so you could advance it onto the spinning drill.

I don't have enough bed length to back off a 22" long piece from a drill that long to clear the chips. I probably would have fastened the work in the headstock and drilled through the hollow tailstock after starting the hole as deep as I could using conventional methods. I think hollow dead centers were designed for this very purpose.

I'm always agreeable to learning another way to do something, but I didn't understand fully your method.

Re: Tip for cheap & dirty way to drill long holes

Barry Irby

>I was one of the 300 people that read your post and did not respond. I thought about it and filed it under possible useful info, but it did not pose a question so I did not post an answer.

About forty years ago I took high school shop. Made a lamp on the lathe out of walnut. I remember turning it as if it were yesterday. Turned the piece down to about a four inch cylinder and sanded it to perfection, then turned it into a sort of vase shape. Still don't know why I sanded it in the middle, but when you are fifteen, what do you know? Made a base for it. I still have the plans if you would like them. Anyway, I tried to drill a hole through it. Put a long steeply angled "end grain bit" in the drill press and tried to drill through end to end. The grain lead the bit off center and it came out the side. I was heart broken.

So, Where were you when I needed to know how to do this? (Just kidding, would have had to invent the chuck first)

Re: Over 300 viewers with no response

Arch

>I hope you thought the "UN's" to be humorous, not peevish. Anyway, thanks for each of your responses. There's no other way to know if we offer a good idea or not without some feedback or suggestions for better ways.

Jay, I wanted to irritate fellow turners enough so safety couldn't be forgotten, but I probably did the opposite with an annoyance that turned out to be more of a turn off.

Al, Sorry I didn't make it clear that the roughed out blank is supported between the tail center and the drill bit itself. The long bit is started in a predrilled hole that's deep enough to hold the blank between the bit and a regular tail center. The blank is kept from rotating with the left hand, directly or with a strap wrench and the hole is drilled by moving the blank into the rotating bit by cranking the handwheel with the right hand. When tail spindle travel is completed, the tail center is cranked back, keeping the blank tight against it. Then the collar is loosened and chips cleared by moving the bit outboard. Then the bit is advanced to the end of the blind hole and the collar tightened. This sequence is repeated until the hole is finished. The chips are removed and the hole cleared by moving the bit thru the collar and spindle hole to the left, not by moving the blank to the right, so any blank that will fit between the lathe's chuck and tail center can be drilled and cleaned out. Reversed rotation helps clear the hole of caked chips.

This seemed like a simple method that uses a scroll chuck, the usual tail center and a cheap HF long bit to drill long small holes. It is easier done than explained. I've probably left a major step out, but I know it works. I've got a stick of wood with a hole in it to prove it. :)

Re: Tip for cheap & dirty way to drill long holes

Scott Hogsten

>I was one of the three hundred that read it and while interesting it's not something I would use. Not to Hijack your thread but I would still take the time to make a D-Drill for a really long hole. For those of you asking what a D-Drill is, here is how I make one. Buy a piece of drill rod the diameter of the hole you want to drill (let's say 1/2 an inch). Head to the grinder and for the first two inches of the rod grind away roughly .245 of the .500 rod, it doesn't need to be exact for the full length but but does need to be close at the tip. If you look at the tip of the drill rod it now has a "D" shape. Next grind a relief on the end of the bar, 75 degree works well. By this I mean to make a scraper grind on the end of the bar. You could use the drill at the point but I like to make a slight modification to the drill to make it feed better. holding the bar in front of you with flat area facing you make a mark 1/4-1/3 of the way from the left edge of the flat area. Go back to the grinder and make a slight point with the mark being the tip. You don't need much of a point at all, just enough that you can see the bar isn't straight across any more. Make sure you still have the 75 degree relief cut and you are ready to drill

To use this drill , slow the lathe way down, under 300 rpm, 150 if your lathe can got that slow. I like to make a slight starter hole to get it going using a gouge or a scraper. Use a steady pressure to feed the drill in and pull it out frequently. If you are drilling really deep using a little mineral oil or pure linseed oil will help lubricate the bit. I've drill holes on center over 30 inches with this type of bit.

Scott Hogsten

Re: Tip for cheap & dirty way to drill long holes

Arch

>Thanks a lot Scott. Good description, just what I hoped for. My problem with long thin D bits is the feeding. I find that cranking the tail ram in steps, altho taking longer, is much easier for me, but I've gotten so weak and arthritic that when my barber asks about trimming my eyebrows, I nod yes. No need to look tough if you can't back it up! :(

I really offered the tip as one dodge for turners who don't have a hollow MT tail center or a Jacob's hollow headstock chuck.

Re: Your's is very close to the gun drill tip.

Al Crandall --NE of Indy--

>A gun drill has no relief on the sides of the tip, so the hole has full bearing on the o.d. of the drill and acts as a guide. The single flute has two different grind angles on it to create a point which is off set from the drill centerline. Yours has two also, but one of them measures 0 degrees. The reason that this grind drills so straight is that the lip nearest the wall of the hole is longer than the lip nearest the center. It exerts more pressure because it is removing more material. This tries to force the drill away from the wall, but because the drill has full bearing on the o.d. it can't be forced off center. By the same token, the assymetrical force on the tip keeps the drill from moving into the wall and drilling an oversize hole, which would allow the drill to wander and not drill straight.

When you grind the angle on the corner of the tip, you need to relieve the other corner of the drill, on the non-cutting side, by a greater amount so it won't rub in the bottom of the hole.