How to make a decent bore?

[ohno]

Does anyone have some advice on how i could do a hole 20 mm diameter 1m long through some timber.
I need to do a bore for a shakuhaci flute so i need it precise. is there some sort of setup i could jury rig?

:~
Ta

[Malibu]

I'm not sure that anything you could do would run true over a meter through timber. The only drilling method I can think of is a set of extension bars on an auger, but it would wander all over the place.
Another way that might work is to route a channel in two seperate pieces of timber (maybe ripped down from the same piece to keep the grain true) and glue them together later on.
Sorry, that's all I can come up with... :-

[echnidna]

I remember reading a book about making a clarinet years ago.
( it was in the Bendigo Library but I don't recall the books name)

Its method was to make it in 2 halves with a core routed lengthwise.
After laminating together you cleaned and trued the bore with a home made hand reamer.

The reamer was just a single cutter sandwiched between 2 half round wooden sides. I think the reamer was only used to take about 1.5 mm out.

[Iain]

I saw a similar thing to Bob for boring out a recorder, was a timber rod with a groove and a blade inserted to ream out a taper that is required for accurate tuning.

[ohno]

Thanks guys. I had a feeling its going to be tough. :rolleyes: Iam going to try and do it in one piece somehow and hope for the best. Anyone know of any engineering forums:D

cheers
ben

[DJ’s Timber]

I have a couple of ideas forming in my head, I will have a play with them in the shed and see if its feasible, will let you know what happens.

Out of interest, what type of timber were you thinking of using as this could have some bearing on whether it works or not too

[ohno]

sassafrass.
Measurements 55x 60 x 800
Cheers

[joe greiner]

How about drilling the bore on an oversize blank first? Let the bit wander to its heart's content (within reason). Put a plug in each end of the hole to engage the lathe centers. Turn to final shape.

Joe

[arose62]

Try googling for "gun drill" - that's what's used to bore gun barrels.

Cheers,
Andrew

[DJ’s Timber]

Well I had a bit of a poke through my gear which I use for long hole boring and I can only get about 400mm maybe 450mm with what I currently have. Could come in from each end but can't guarantee that the holes would meet up :no: .

I could buy some gear that would allow me to bore either a 5/16" or 3/8" hole in from each end which I reckon would meet up pretty much spot on, as long as I took my time :C. The only drawback is that it will cost me about $250 to get it set up :o.

Which is an expensive exercise to see if it will work or not :B.

[kiwigeo]

Does anyone have some advice on how i could do a hole 20 mm diameter 1m long through some timber.
I need to do a bore for a shakuhaci flute so i need it precise. is there some sort of setup i could jury rig?

:~
Ta

I had a Japanese shakuhachi player around for lunch here today. I asked him your question and his response was that traditionally the instrument is made from bamboo and "boring out" is a simple matter of putting a hole the bamboo partitions...the instrument is usually made from a length of bamboo with only one partition. Apparently a hot poker tool is used to burn out the partition.

[ohno]

I had a Japanese shakuhachi player around for lunch here today. I asked him your question and his response was that traditionally the instrument is made from bamboo and "boring out" is a simple matter of putting a hole the bamboo partitions...the instrument is usually made from a length of bamboo with only one partition. Apparently a hot poker tool is used to burn out the partition.

I've made several bamboo ones but i really want to do one out of a solid piece of timber in order to have more precise(in theory:rolleyes: ) control over the sound properties.

Anyway, i think this project may get put on the backburner through lack of momentum and replaced by any one of the billion other ones i've been meaning to do.:roll:

Cheers
Ben

[joe greiner]

When/if you (or others) return to it, this may help:

http://www.recordpower-usa.com/mastering_long_hole_boring_by_al.htm

Joe

[ohno]

When/if you (or others) return to it, this may help:

http://www.recordpower-usa.com/mastering_long_hole_boring_by_al.htm

Joe

Perfect:2tsup:
Thank heaps

[Malibu]

Just as an after thought, and maybe a bit off track...
How are didgeridoo's made commercially?
I know aboriginals used to use termites to chew out the bore of a clay packed log, and as far as I know, they still do in the NT. Surely the tourist trade in didgeridoos have a different method, and maybe that might shed some light on what you're after? :D