Pilot Holes

[billh]

Dave:

Since those pins are a press fit, does that mean you remove them for sharpening? That would seem much more convenient than the usual integrally-turned pins on piloted D bits, providing they don't get stuck.

In the large-to-small method (including where gun drills are used) since the centering bits are guided by their outside diams, they lend themselves to a simply sharpened form.

Bill

[PaisleyBuddy]

Incidently, how you store your wood at this point can make a big difference in if and how much it warps. Tim Britton

Can you elaborate on this Tim?
Much appreciated

[daveboling]

Dave:

Since those pins are a press fit, does that mean you remove them for sharpening? That would seem much more convenient than the usual integrally-turned pins on piloted D bits, providing they don't get stuck.


Bill

Bill,
I use what you might call a "loose" press fit, which would be between a true press-fit, and a slip-fit (more like a buggered slip fit with my skills ). A bit of oil (whatever you normally use for wood drilling/reaming works to keep the dowel pin from seizing in the cutting bit. If the bit gets hot enough to grab the pin, the feed rate on the cutting bit might be a little fast. If the dowel pin comes loose in the bore, a small diameter piece of drill rod, or wire will easily push it out (just don't drop it on the shop floor like I am want to do )

dave boling

[upiper71]

I thought that this thread had fell off the planet, but it is sure interesting to see, and learn from.

Daryl

[daveboling]

It didn't fall off the planet, but with me trying to explain things, it may get dangerously close to the edge.

dave boling

[upiper71]

It didn't fall off the planet, but with me trying to explain things, it may get dangerously close to the edge.

dave boling

Dave, you should demonstrate in pictures, perhaps your point will come across more vividly.(No pun intended)

Daryl

[upiper71]

Why not just one pilot hole and straight onto the reamer(s)?

DavidG

Well, two things - it's faster, and it saves wear on the reamers.

If you're using hardened steel multi-flute reamers, instead of homemade reamers, these may be minor considerations, but chances are pretty good that such reamers (which are almost certainly ''sent out" to a big machine shop or toolmaking firm) are going to be straight tapers. See previous threads for discussions about straight vs wiggly tapers. If you do manage to find a machine shop that will make a complex taper on a reamer, how sure are you that they will meet your spec?

Even if you have achieved that perfect bore design and are ready to spend the bucks for a 'professional' multiflute reamer, those things can be hard to sharpen. Even the hardest tool steel will dull fairly quickly when used on ebony, so there's still something to be said for roughing out the bore with something else (like step drilling).

I suppose an alternative is to get an undersized "straight" reamer and rough out the bore with that, then finish up with the specialty reamers.

Bill

Bill, I enjoyed the last bit of what you said as an alternative(for a beginner) to use the specialized reamer near the end of completion. I will begin with that... with the Honduras rosewood I've got. I dont know if it'll work well but I'll sure try it out for starters. If I don't flippin break the darn thingy out.

[ausdag]

Why not just one pilot hole and straight onto the reamer(s)?

DavidG

Well, two things - it's faster, and it saves wear on the reamers.

If you're using hardened steel multi-flute reamers, instead of homemade reamers,

What you say Bill is true, however I watched a maker here turn a C# chanter - one pilot hole and straight onto the reamers. Pilot hole and 5 reamers = bumpy, well-tuned bore.

Pilot made with home-made d-bit, 5 reamers also home-made about 15 yrs ago. I ran my finger down the edge of one of them - the number one reamer - and nearly sliced myself. 5 reamers because he hasn't got around to combining them into one or two reamers. I think the reamers are made from good quality steel from old steering columns - that's why they - especially the number one reamer - maintain their edge after so long.

Reamers mounted on metal lathe - chanter hand fed.

Started drilling at 7:25pm, bore finished at 8:15pm. Unfinished chanter (minus polishing and key and mounts) reeded, ferruled and playing at 9:20pm.

I still have the chanter and can't stop playing it.

Cheers,

DavidG

[dirk]

Started drilling at 7:25pm, bore finished at 8:15pm. Unfinished chanter (minus polishing and key and mounts) reeded, ferruled and playing at 9:20pm.

I still have the chanter and can't stop playing it.

Ausdag,

From what kind of wood was that chanter made?

-Dirk

[Joseph E. Smith]

Started drilling at 7:25pm, bore finished at 8:15pm. Unfinished chanter (minus polishing and key and mounts) reeded, ferruled and playing at 9:20pm.

I still have the chanter and can't stop playing it.

Ausdag,

From what kind of wood was that chanter made?

-Dirk

How long was the wood aged and won't it warp over time because it was all done at once?

[ausdag]

Started drilling at 7:25pm, bore finished at 8:15pm. Unfinished chanter (minus polishing and key and mounts) reeded, ferruled and playing at 9:20pm.

I still have the chanter and can't stop playing it.

Ausdag,

From what kind of wood was that chanter made?

-Dirk

How long was the wood aged and won't it warp over time because it was all done at once?

Dirk, it is made of very dry Brazilian Rosewood.

Joseph, I don't think drilling and boring all at once is the cause of warpage. As has already been mentioned here I think, boring has no real effect on the drying process as most of the moisture is lost through the outer surface. I have seen drawers full this makers chanters that he turned using the same process - experimentation over 15 years - that still retain their shape. Should the bore itself shrink, as often happens with the best, most meticulous methods even, it is not a difficult process to re-bore.

Cheers,

DavidG

edited to add a 1 next to the 5

[Joseph E. Smith]

shows you what I know about it.... zip.

[mirabai]

re: drying methods. the main issue is equal access of all sides to air and no pressure on it. With relatively fresh cut wood the initial drying can be quite affected by things like how it's sitting. If you stack the wood in rows with space between each turning square with the next row perpendicular on top of that, etc., it greatly speeds up the process and discourages warping.

Re: boring and turning all at once, it has been my experience that even with well seasoned wood, it will always shrink a little and often warp slightly over time. It is only common sense to spread out the various operations to avoid this problem. Of course, there is little harm in a warped chanter. The only issue is that if you want to put a reamer back up it or put it back on the lathe for repairs years later, you're gonna have problems.

Tim B.

[mirabai]

an an udder ting...

I can think of no reason to think that "most of the moisture is lost through the outer surface" regardless of boring. Definitely not my experience. It is demonstrated quite clearly every day in my shop that the wood dries, shrinks and otherwise moves more quickly and thoroughly after boring.

Tim B.

[IrishPiper42]

I use "taper pin reamers". I use 6 different reamers, #3-#8. There almost the perfect taper. There's some overlap in the sizes so I figured out how deep I wanted to go with each one and where I wanted that particular reamer to stop - that's where I ground the back end of the flutes down. By controlling the amount of overlap and the depth of each one in this way I get the bore to th exact dimensions I want.
-Mike B