drilling long holes

[Steve B]

How would I drill a hole through the middle of a three foot long piece of tree limb to put a lamp cord through there? What if the limb is not totally straight?

Steve

[cselby]

Brad point bits are available that are about a foot long and then there are extensions to lengthen the bits reach. You will have to pull out the bit periodically to clear the chips.

If the limb is less than straight, the hole will off center at some point wouldn't it. You can attempt to drill half way through from both ends. You may get lucky at the holes will meet.

Pete

[John Williams]

"Installer" drill bits up to 72" long are commonly available. They are used for wiring home security systems and the like. I have even seen them at the local Home Depot.

[henry]

I would make the hole bigger than you need fiquring that you wont meet dead center coming in from both sides.

[Mapdude]

Run it through a band saw length wise to end up with 2 halves, then rout your cavity and glue it back together.

Steve B wrote:

[Woodhead]

Is it possible to saw it lengthwise, route a channel and glue it back together? I did thant on an oak post that I wanted an AC power cord coming out midway up the post.

[Tim Taylor]

EXPENSIVE!!! Especially for one or two lamps. I know, I use them in my line of work, I've got half a dozen or so. Find a phone or cable guy and you might get lucky and he'd sell you one for a little of nothing. Otherwise, saw it in half, cut a channel and glue it back together.

[Prometheus]

If you do go with the long bit, and it's green wood, a spade works better than the threaded auger bits. I made a lamp or three, and the auger clogged way too quickly to be worth the money I paid for it. They do work well in dry timber, though.

Good luck, whatever you go with- I don't envy you that job! A 14" lamp of green wood was a lot of hassle to deal with, I can't imagine

3'.

[Australopithecus scobis]

Seems like a rough thing to do to an expensive bit, but go figure...

[warbler]

I made a lamp using about a 20inch section of Birch just a few months ago. Since I only have a small bench to drill press, I did it in two steps. I intially clamped the piece to the table on the drill press that had been turned - rotated - to be parallel to the drill bit. I then centered and drilled a beginning hole as long as my press would allow. I followed on with a long drill bit mounted in a cordless drill. But now I at least had confidence that the hole would be directionally accurate. It takes a little time to get the hole drilled. But it worked because I then screwed a long threaded lamp post that I then cut to size with a hack saw.

After mounting it on a hardwood base, the project came out really nice. Hope this helps.

[Tex]

I don't know whether this will work for for you or not, but I've made holes thru long pieces (always with a rectangular X-section, though) by ripping the piece open on the table saw, cutting a dado in one side, and glueing the two pieces back together. For your tree limb that's not straight, you'd have to fasten it to something straight to run against the fence. Also, the kerf thickness that's lost might cause a problem when you try to realign the curved surfaces. This is just a thought that you might keep it in mind if you don't get a better solution.

[Robert Bonomi]

A) "*VERY* carefully" B) "with a three foot long drill bit" C) laser cutter?

The 'easy' way is if you can rip the piece in half, excavate your center channel, and glue the pieces back to together.

Another alternative is to chop the piece into, say, a dozen 3" sections, drill each section individually, and re-assemble.

If you don't like either of those alternatives, see the smart-ass answers list above. :)

You need a 'limb-er' bit. *groan*

To _drill_ all the way through, the piece has to be 'straight enough' that there is a "straight-line" path through the piece. (Well, if you're _really_ good, you can drill from both ends, and have an angle where the two holes meet.

Either of the 'divide and conquer' techniques mentioned above will work where the stock is _not_ 'straight enough' for the straight through approach.

[Roy Smith]

What's the diameter of the limb? I'm assuming it's fairly large and you don't mind hogging out a lot of material.

I'm thinking maybe this could be done in stages. Start with a 2" diameter forstner (or maybe a spade) bit and drill a hole (say) 4 inches deep.

Next, take a 1-1/2" diameter bit, attach it to a drill extender (a nice looking one is

and drill down another 4 inches. Because the first forstner left a flat-bottom hole, and you're picking up with a smaller bit, you are able to adjust the axis of the hole to follow (within limits) any bends in the limb. And chip clearance should be easier with the stepped hole.

Repeat with a 1" bit and a longer extension. And again with a 1/2". That should get you 16" deep. Repeat from the other end. You've now got 4" in the middle to go through with a regular bit (on a long extension). Play with the details as needed to make it all work out.

You'll end up with two more-or-less stepped conical holes meeting in the middle. Assuming it all works. I've never actually tried anything like this; I'm just thinking aloud.

I would only attempt this on a drill press, and would invest a lot of time building some nice jigs to hold the workpiece firmly at the required angles. I'd also practice on some scrap before putting metal to the real thing, just to make sure it all works. Things might get pretty floppy once those extensions get long.

[Owen Lawrence]

Yeah; and some kind of strong glue you'd need too, eh?

- Owen -

[Owen Lawrence]

What about a boring bar? Never done it myself, but it seems like it would work, if riflers can use it to bore accurate holes.

My uncle once made a lamp from a limb that had a crook in it, and a knothole at the crook. He drilled through the end and out the knothole, then changed direction for the other half of the limb, drilling into the knothole and out the other end. He fished the wire though, easier now because of the halfway access, and then filled in the knothole with filler and stained it to match. It worked well, and people had to ask to figure out how he got the wire through that thing.

- Owen -