End drilling log help?

[wirebabe]

I have a log project that requires drilling into the end grain of 7 logs (about 12-14 in. diameter each), at approximately 30 inches deep and just over 2 1/2 inches in diameter (the hole will slide over a galvanized pipe that is 2 1/2 inches outer diameter).

I'm just outside of Seattle, and need this done within the next few weeks if possible, and it needs to be done right the first time. These are fir logs that were dredged up from the bottom of Lake Union after 70 years underwater, very clear grain, nice.

Thanks for any suggestions!

[loghomefun]

I would suggest a drill and a drill bit. When you want to drill a hole, that is usually the best route to go.

Large diameter auger bits are available. You local rental company might have one, or try a drill bit company like http://advantage-drillbits.com/auger.html

Doug

[wirebabe]

Thanks Doug. The issue is not the hole, but that it is as long and wide as it is, and into the end grain of the wood.

Anyone with helpful suggestions?

[loghomefun]

Thanks Doug. The issue is not the hole, but that it is as long and wide as it is, and into the end grain of the wood.

Anyone with helpful suggestions?

That website lists auger bits that are up to 8" in diameter, and up to 192" long.

So a bit that is 2 1/2" in diameter and 32" long should be available, from them or elsewhere.

Drilling from the end grain of from the side, it does not matter you still want to make the hole with a drill and a drill bit. Center the bit, keep the drill level, and go slow. Good luck!

Doug

[Kama]

Wirebabe,
One thing you might come across when drilling is that since it's end grain and such a large dia. that the hole will get clogged up easily. Most bits are designed to slice across the grain like a cross cut blade for a saw.

Something that might help is a jig to help keep the bit straight in the log. I'm thinking this thru and I can see you having to back out the bit to clean out the hole a lot and you'll want to make sure that you stay on the same path when you reinsert the bit. Sorry, but nothing is coming to mind on how to accomplish this. If something does pop into my head, I'll post it.

[adubar]

wirebabe, as loghomefun posted there is a quite a selection of bits to choose from.

As you are in Seattle, you might try Hardwick's on Roosevelt Way.

Also, if for any reason you run into problems drilling with a power drill, a bit brace will work. In the boating industry it is still the only real way to get enough torque to drill for stern posts and keel bolts through thick hardwood. 30" is not uncommon to drill and on some large boats may be up to five or more feet!.

Irwin still makes some very long and wide bits. Some local hardware stores carry them as well, but 2" or more diameter may be harder to find (Hardwicks tends to have EVERYTHING, though).

As for a jig, sometimes a simple "angle" made from two pieces of perpendicular wood with the bit nestled in the "v" is all that is needed. If you have a steady hand and eye, you probably won't need a jig.

Good luck!

-A

[Squirt_TN]

I think that I would try to "step-up" my hole as I go. Start with a smaller bit say 1/2"x12" then move up to 1"x18" and so on, this "should" prevent a lot of "walking" of the bit. I believe that this would give you a little more control rather than just jumping to 2". Good luck :D

[adubar]

If you use a good auger it won't walk, if you go slow. You should not need to drill a pilot hole either, as they are self starting if they have a threaded point and spurs. You might need to clear out chips along the way though.
These types of bits are used in timber framing. They are meant to drill trough large timbers, even by hand.

I would be concerned about the type of drill used to power the bit. A 2 1/2" dia. plus hole will require quite a bit of wood removal on each turn. It might be the kind of thing that burns out an underpowerd drill quickly.
So, get adequate power behind it. You could do it by hand, but it will be tiring.


-A

[rreidnauer]

I would be concerned about the type of drill used to power the bit. A 2 1/2" dia. plus hole will require quite a bit of wood removal on each turn. It might be the kind of thing that burns out an underpowerd drill quickly.
So, get adequate power behind it. You could do it by hand, but it will be tiring.

Agreed. Get youself a Milwaukee Hole Hawg. I've used them professionally for years, as an electrician, and I own one of my own. I can't say enough good things about it. It will dish out more than YOU can take. When putting up my aircraft hanger, I used it to run 4 inch auger anchors into the ground without the slightest sign of struggle. It's a drill that demands respect when you use it in low gear. (yes, it's got two gears) Don't mistaken this drill for a plumber's angle drill. It's not.

http://www.jobsitetoolsdirect.com/products/mil/images/xs/1675-6.jpg