source for long drill bits

[richbeck]

I am getting ready to drill long holes for anchoring my deadwood on a North Sea 29. I need to drill holes about 30 inches long and need a 1/2 bit approximately 48 inches long to allow for use with a guide for drilling. I am think a twist bit in the event that I inadvertantly got a ring shank nail in the wrong place (although I dont think I did), but a auger bit might be a better choice. Have searched the internet, and also the forum search but with limited success. Anyone have any links to a supplier?

[Peerie Maa]

I am getting ready to drill long holes for anchoring my deadwood on a North Sea 29. I need to drill holes about 30 inches long and need a 1/2 bit approximately 48 inches long to allow for use with a guide for drilling. I am think a twist bit in the event that I inadvertantly got a ring shank nail in the wrong place (although I dont think I did), but a auger bit might be a better choice. Have searched the internet, and also the forum search but with limited success. Anyone have any links to a supplier?

Buy a couple of ordinary 1/2 inch bits, take them to your local blacksmith or fab shop, and have them weld 4 foot of round bar on as an extension.

[donald branscom]

You do not get a longer drill bit, you get a drill bit extension holder.
http://i47.tinypic.com/2pqp2tz.jpg

[richbeck]

My concern with using a bit extension is the ability to use a guide to align the hole. I suppose I could use a guide to start the hole and for the first few inches, then use the extension with the hole being the guide from that point on.

[donald branscom]

My concern with using a bit extension is the ability to use a guide to align the hole. I suppose I could use a guide to start the hole and for the first few inches, then use the extension with the hole being the guide from that point on.

I understand. Are you drilling the hole for the prop shaft?

Usually if you drill half of the hole from one end and half from the other end it helps to keep things straight.

What is the total distance you have to drill? If you tell us maybe we can tell you how difficult it would be.

OK...OK I re read the thread.
I would not worry too much since it is the Dead wood. It is better if all the holes are not in line anyway. Use a 2x4 guide temporarily attached to the dead wood to act as a guide.

Many boat builders do this all the time. I am surprised they have not jumped in here to help you.
I believe the augur bit is good for this.

[Bill R]

If you are concerned about alignment, you may want to start with some longer bellhanger bits- get the first 18" or so started.

[ssor]

try McMaster-Carr. :http://www.mcmaster.com/#bell-hanger-drill-bits/=78cibr

[richbeck]

the longest hole is about 26-28 inches long. Maybe jig up and drill the first several inches with a long twist bit (18 inch irwin or similar) and then change to an auger bit and let the hole be the guide? What do you think? Maybe less friction with the auger.

[Paul Girouard]

Check with electrical supply houses in your local area.

[Canoeyawl]

I just make them up...
Turn the end of the drill bit down and thread it, then drill out the extension
and tap it. Sometimes if I/m feeling fancy I'll mill three flats on the extension end.
Voila...

[The Bigfella]

Posts 105 on for a bit in this thread show how we did it

http://forum.woodenboat.com/showthread.php?t=87382&page=3&highlight=yellowtail

http://i240.photobucket.com/albums/ff112/igatenby/v3.jpg

details in the linked thread - we used grub screws to hold the bit into a holder we made

[Cecil Borel]

Rich: you may want to try these guys for a long drill bit. http://www.advantage-drillbits.com/ I would suggest that you use this bit for a pilot hole, and then use a boring bar to expand the hole to the true diameter and orientation. The WBF has some of this info in older posts, and I can help with the boring bar construction

[richbeck]

Great pictures of drilling for the prop shaft. I will definately be revisiting your tutorial when the time comes to do mine!

[richbeck]

Thanks Cecil. The holes are only for 1/2 inch silicon bronze rods through the deadwood for added support. I will take you up on the boring bar info when time for drillling for prop shaft.

[J P]

48" for a 1/2" bit is really going to be a problem. I don't think I've ever seen a bit extension that would go that long, in that small a size.

The log home guys have auger bits up to 60" but they're all 1" or larger.

http://www.loghomestore.com/tools-drills-and-bits.shtml

Those guys have one vendor who says they have 1/2" by 48"... but that's a lot of torque being delivered into a very small shaft... I'd be worried about it twisting into a pretzel with any kind of resistance... and even with a guide, it's going to flex all over the place. Getting a straight hole... Best of luck.

You're going to need a very high torque, very low speed drill. They make special ones just for log homes. The vibration, and the binding on something like this is going to be epic.

Agreed. Smaller augers twist from the torque, some worse than others, and they tend to drift to the left because of this.

I think the long ½” bits in that loghomestore link are the 'Eliminator' brand from B&A Manufacturing (http://www.bamanufacturing.com/page_01.htm). Good bits, we have a few, but from a different supplier.

Another bit that we’ve had good results with is the Wood Owl (http://www.woodowl.com/PROD_nailchipper.htm), although I don’t believe they have any ‘extra’ long ones. Their tri-cut augers do actually work pretty well and they have one that they market as a nail cutter.

I wouldn’t use an extension that relies on set screws for something like this; too much risk of losing a bit. And I’m not sure you can find one that will fit in a ½” hole. If needed, I’d go with fabricating a bit onto a rod as already mentioned by others.

Start the hole with a stiff, sharp bit and a good guide. Switch to longer bits as needed and be diligent about clearing the chips.


We use a variety of long bits, some ‘off the shelf’ and some home brewed. Here's a couple.

http://i7.photobucket.com/albums/y279/picsonline/m_IMGP6578.jpg

We use a variety of guides depending on what we are doing. Recently drilled 1” holes 7 feet through the center of some old dry 12x12 white oak. Started with this:

http://i7.photobucket.com/albums/y279/picsonline/m_IMGP6602.jpg

and two 4ft bits

http://i7.photobucket.com/albums/y279/picsonline/m_IMGP6601.jpg

First the solid shaft bit, 18 inches or so, followed with the auger. Generates some absolutely hellacious, torturous, screamching noise from the friction when the bits are in deep.

http://i7.photobucket.com/albums/y279/picsonline/m_IMGP6589.jpg








North Sea 29 looks like quite a project. Will it be for Flathead?

[richbeck]

Thanks guys for all the info. It really is helping to point out the many options for accomplishing the task. Sounds like a twist type bit, if used, should not be counted on for drilling the entire depth. I think that I will jig up and drill as far as possible with an 18 inch irwin bit and then finish up with an auger bit being sure to clear it of chips often

JP
The North Sea may be put in Flathead Lake, but ultimately it is destined for the ocean (San Juans)
Thanks again for all of the help.

Richard

[Mrleft8]

W.L. Fuller.