Cutting Coring Dowels

Indicate your gun drill near the tip down to 12" from the tip.
I think it's off.
If it's a tailstock mounted one, your tailstock is off.
Mine is tool post mounted one.
I stick a magnetic base indicator on the bed near the chuck.
I indicate the side of the drill.
I get within 2 thou the length of the rod to be drilled.
I power bore the entry and exit holes first before gun drilling.
.008" total clearance is plenty for me.

I check my tailstock with a ground 1/2 steel dowel and I can turn a 24 in piece within 2 thou on the ends... so that is not the problem.

If I carefully bore the starter hole for the gun drill, I can drill an 18 in piece with in a few thou end to end.... so the gun drill is not the problem.

The problem is push off when I turn a 30 in dowel between centers. The center is fat and the ends are perfect. If I slowly run the router over the center a few times without changing the setting, it will come down to about .010 fat. Then I have to sand it to fit. PIYA

If I turn a 1.375 piece the center is the same size as the ends. It doesn't flex.

I get the least push off with a 3 wing cutter that is 1/16 thick but then I get a vibration.

I am going to try to turn 1/2 of the dowel at a time by holding one end in the chuck and the other in the tailstock live center. Just a thought....

Kim
 
Kim,

Do you happen to have a follow rest? Given that this is a core, you wouldn't mind the slightly different texture where you moved the rest and recut - but you probably know this.

Just thinking . . .

Gary
 
Kim,

Do you happen to have a follow rest? Given that this is a core, you wouldn't mind the slightly different texture where you moved the rest and recut - but you probably know this.

Just thinking . . .

Gary

I have to admit that I had to go look up what a follow rest was. I have never heard of one or seen one and I worked with some guys that were tool makers and machinists.

That is an interesting device but I don't know if there is one that will mount on a Hightower lathe.

thanks

Kim
 
Hi,

Actually the Hightower headstock is a perfect thing to hold a piece your going to core on the outside ends of the stock. No need for collets! I have never done a fully 30" one piece like Kim does now and then but that would be a good place for him to use a follow rest or steady rest. But what the hell he is getting the job done this way.

I don't have a Hightower so I use a steady rest on an Enco lathe.

Rick

I do my forearm stock at 16.5 inches long using the rest and the jaws.
IMG_4759.jpg
 
I have to admit that I had to go look up what a follow rest was. I have never heard of one or seen one and I worked with some guys that were tool makers and machinists.

That is an interesting device but I don't know if there is one that will mount on a Hightower lathe.

thanks

Kim

If there is not one, one could easily be adapted I am sure. Little Machine shop has 3 or 4

http://littlemachineshop.com/products/product_search.php?criteria=follow+rest&Search1=Search

Chris H. I'm sure would know.

I make my cores 15" long and .740 and have no problems cutting the same size along the length.

Dick
 
Hi,

Actually the Hightower headstock is a perfect thing to hold a piece your going to core on the outside ends of the stock. No need for collets! I have never done a fully 30" one piece like Kim does now and then but that would be a good place for him to use a follow rest or steady rest. But what the hell he is getting the job done this way.

I don't have a Hightower so I use a steady rest on an Enco lathe.

Rick

I do my forearm stock at 16.5 inches long using the rest and the jaws.
IMG_4759.jpg

Good Lord, look at those burn marks.
 
Kim, have you considered the 6 wing that Cue Components sells?
I got one and the shafts come out as smooth as a baby's bum.
No chatter marks.
 
I check my tailstock with a ground 1/2 steel dowel and I can turn a 24 in piece within 2 thou on the ends... so that is not the problem.

If I carefully bore the starter hole for the gun drill, I can drill an 18 in piece with in a few thou end to end.... so the gun drill is not the problem.

The problem is push off when I turn a 30 in dowel between centers. The center is fat and the ends are perfect. If I slowly run the router over the center a few times without changing the setting, it will come down to about .010 fat. Then I have to sand it to fit. PIYA

If I turn a 1.375 piece the center is the same size as the ends. It doesn't flex.

I get the least push off with a 3 wing cutter that is 1/16 thick but then I get a vibration.

I am going to try to turn 1/2 of the dowel at a time by holding one end in the chuck and the other in the tailstock live center. Just a thought....

Kim
Might be of help.
Keep the handle section of the dowel at .875" final size, get a gun drill at .885". Now, you can keep 17" or longer ( after all the bottom of the forearm is about 1" up to 3 inches deep ).
Adjustable speed router or rheostat and use 3 or 6 wing cutters at 18,000 RPM max.
http://shopping.yahoo.com/765544695...er-1-14-dia-x-316-kerf-x-38-24-threaded-bore/
Steady rest and bearing could be of help too but if you keep the bottom 17-19" at 7/8, you might be able to machine .6875 by 10" long from chuck to tailstock.
 
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Good Lord, look at those burn marks.

Joey,

I core at 260 rpm and put wax on the wood. Most of the black is smeared wax but it does build up a little heat. The gun grill creates more heat to the stock. Anyway it all comes out in the wash on any species. The cores are done at 1 3/8" and the A Joint size is .980. I am not a wood worship person but I don't abuse it either.

Anyway I like to burn the wood real good because it gets rid of that high pitch annoying ping sound!! :groucho::poke: "Just Kidding"!!:grin-devilish:

What I won't do is take a torch to a pin. That burns the wood in the core!!! I have a secret for taking out pins without a torch.:scratchhead:

Rick
Mostly wax with a little heat
IMG_4752.jpg

I don't see any burn marks here do you?
IMG_4869.jpg

None Here either
IMG_4857.jpg

IMG_4859.jpg
 
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Joey,

I core at 260 rpm and put wax on the wood. Most of the black is smeared wax but it does build up a little heat. The gun grill creates more heat to the stock. Anyway it all comes out in the wash on any species. The cores are done at 1 3/8" and the A Joint size is .980. I am not a wood worship person but I don't abuse it either.



Rick
Sealed bearings are cheap. :grin-square:
.980" ? Pretty slim for a parabolic taper
 
Sealed bearings are cheap. :grin-square:
.980" ? Pretty slim for a parabolic taper

Joe,

To each their own. I am a pragmatist, if it isn't broke don't fix it. I don't thread my ferrules or butt caps either as I also think it is a waste of my time that does not make my cue play better. JMO. If one is happy doing those things, let them eat cake and be happy. I will take a proper slip fit and G5.

Yes, my taper is not straight, .254 at the butt with the curve extending through the handle area with the A Joint at .980. Then the forearm close to almost conical to .850 at the joint.

So my butt taper is kinda like a subtle trumpet shape. A trumpet is designed to produce a amplified laminar flow to the high frequency sound waves. My butt taper is designed to transmit the low frequency in that laminar design but the shock wave is diffused in this case.

Here is a real world example to illustrate how powerful this effect can be channeled:

Nicola Tesla the electrical genius and greatest mind world has ever witnessed used this laminar flow principal to beat physical science in a hydraulic sense.

As the Electrical Design Engineer for the Niagara Falls Hydro Dam Project in the 1890s he became fascinated with the Francis Water Wheel which was the water turbine's impeller type rotating unit that turned the generator via the water supplied by the dam and controlled via the wicket gates as a throttle mechanism.

The Francis wheel had been developed to a perfection in that time as it's subtle curves and pitch contours had been refined since the 1700s. Even today with computer generated modeling the Francis Wheel is almost exactly the same.

Tesla realized that the wheel was as efficient a design as possible but he wanted to increase the efficiency of the dam to create more Megawatts from the Hydraulic Head or potential energy created by the depth of the dam.

His solution was to create a vertical hydro foil directly below the water discharge directly under the water wheel. This was a double parabolic tapered very thin bell shape unit that split the downward force of the water and directed it's forces into two rotating flow patterns that rolled into the tail race discharge instead of one downward force that was not laminar. Before Tesla the discharge created a destructive turbulence downstream of the wheel. Tesla's design created a small partial vacuum.

When his design was tested the net result was an increased efficiency which today is used on every Hydro Dam in the world. This design actually resulted in a situation whereby the dam's elevation or hydraulic head was increased by over 5 feet. Today this translates into billions of dollars annually in increased revenues for the improved design.

The funny thing about this was that Tesla was the Greatest Electrical Man who ever lived and during his idol time while eating his lunch every day he became interested in hydraulic design efficiencies and became the number one guy in the Dam Hydraulic engineering biz. All because of the parabolic taper that increased the velocity of the media and lowered the pressure under the water wheel thus creating that small partial vacuum which added more horsepower to the turbine. Pretty cool.:dance:

So never underestimate the physics behind flow or frequency dynamics created by a parabolic curve or taper. It is very a powerful part of the physical universe. If it helps someone to make just one extra money ball, what is that worth. LOL :joyful::help:

Rick

In the case of the pool cue, the taper defuses the amplitued of the hit because the surface area of the diameter increases as the wave moves down the X axis. The differential or result of this effect becomes more drastic if the the cone is not a constant taper. I like to have this decreased taper area to happen in the area a player would locate his hand an I also like a thinner handle as a design feature.

Because the shock wave of a cue ball hit is measured in microseconds, who knows how much feed back efficiencies if any are gained. Not much, but I will take just a little and be very happy. Thus my .890 A-Joint with the parabolic taper. It is an anti fat spaghetti noodle concept.

Everyone has has their own bend to the brim concern their taper(s). I build just one and this is it.:outtahere:

IMG_4670.jpg
 
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Yes, my taper is not straight, .254 at the butt with the curve extending through the handle area with the A Joint at .980. Then the forearm close to almost conical to .850 at the joint.

It looks straight to me.
Afaik nothing is straight on parabolic tapered butt.
You can't have partial parabolic and then straight and still be parabolic.
Maybe a curved handle then a straight angle.

Gus Szamboti solved this cue riddle a long time ago. Stiff forearm and responsive handle. So did Harvey Martin and Tad Kohara imo.
The size of the A-joint had nothing to do how slim the handle is.
 
]In the case of the pool cue, the taper defuses the amplitued of the hit because the surface area of the diameter increases as the wave moves down the X axis. The differential or result of this effect becomes more drastic if the the cone is not a constant taper. I like to have this decreased taper area to happen in the area a player would locate his hand an I also like a thinner handle as a design feature.

Because the shock wave of a cue ball hit is measured in microseconds, who knows how much feed back efficiencies if any are gained. Not much, but I will take just a little and be very happy. Thus my .890 A-Joint with the parabolic taper. It is an anti fat spaghetti noodle concept.

Everyone has has their own bend to the brim concern their taper(s). I build just one and this is it.:outtahere:
[/B]
IMG_4670.jpg


how? or what? would the internal structures affect be on the shock wave,

different materials, sizes...ect.


is that tesla guy the same one thats make the cars? or did he start the
company?

thanks.
 
Joe,

You are correct about that concerning these great cue makers and their design concepts are well known. A lot of what you are talking about takes into the consideration that those cues are designed with an A- Joint connection pin. My cues do not have a connection at the A Joint and are naturally stiffer from the handle to the pin so that point is mute. It is a different animal.

Take an and A Joint cue, put it between centers and push down at 12" from the pin. Now do the same with a fully cored cue. You will see what I am talking about. Now do the same with a full spliced cue, it is even stiffer. Darrin and I have conducted this experiment many times with many cues. This is the reason I make full cored and he makes full spliced. People who understand this are our customers.

If I were making an A-Joint cue I would want the A-Joint to be larger for sure and I understand your point. There is a natural tendency for a lateral flex in that area when using a joint method and the woods are end grain at the connection.

Rick
 
Joe,

You are correct about that concerning these great cue makers and their design concepts are well known. A lot of what you are talking about takes into the consideration that those cues are designed with an A- Joint connection pin. My cues do not have a connection at the A Joint and are naturally stiffer from the handle to the pin so that point is mute. It is a different animal.

Take an and A Joint cue, put it between centers and push down at 12" from the pin. Now do the same with a fully cored cue. You will see what I am talking about. Now do the same with a full spliced cue, it is even stiffer. Darrin and I have conducted this experiment many times with many cues. This is the reason I make full cored and he makes full spliced. People who understand this are our customers.

If I were making an A-Joint cue I would want the A-Joint to be larger for sure and I understand your point. There is a natural tendency for a lateral flex in that area when using a joint method and the woods are end grain at the connection.

Rick

A fully cored cue still has an A-Joint. You still have two tubes meeting 12" or so from the part.
A 29" long rod , however done still is a 29" rod.
The dimensions, among other things, will dictate how that rod feels on the grip hand and how much energy it can transfer.

I've done one piece butt out of opposing grain laminated bubinga. I didn't make it skinnier b/c it was one piece.
 
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A fully cored cue still has an A-Joint. You still have two tubes meeting 12" or so from the part.
A 29" long rod , however done still is a 29" rod.
The dimensions, among other things, will dictate how that rod feels on the grip hand and how much energy it can transfer.

I've done one piece butt out of opposing grain laminated bubinga. I didn't make it skinnier b/c it was one piece.

Joey,

If you try the experiment I described, you will understand. There is nothing more to say.

Darrin's cue is super stiff. My cue with the .980 A Joint is as stiff as an Omega DPK with the big phenolic threaded deal and fat A Joint. Fact with no histrionics or mysticism.

Rick
 
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how? or what? would the internal structures affect be on the shock wave,

different materials, sizes...ect.


is that tesla guy the same one thats make the cars? or did he start the
company?

thanks.

Hi,


The total area of the cone increases as you go out on the X and this increased surface defuses the energy because the footprint of aspect ratio area gets larger. The rate of this diffusion is defined by the taper. I know we are splitting hairs here but hairs can be split.

I hope the OP excuses this highjack but I have been a Tesla fan since I was 13 years old:

Nicola Tesla was the greatest genius and his contributions changed the world we live in in such a profound way it is unreal and incomparable to any other human being. Here are just some of his contributions to humanity from my memory of the topic:

Developed the concept of the Polyphase motor and is the father of Alternating Current which is the basis for the power grid and power distribution world wide.

Invented the coil.

Invented the Cathode Ray tube and was the father of Television.

Father of Radio. Was the first person to demonstrate wireless radio intelligence ( before Marconi ) and demonstrated the concept in front of the top electrical engineers of the day at Madison Square Gardens in the early 1890s.

Experimented and proved the Franklin theory of electron flow to be wrong concerning the earth's polarity.

Invented the florescent bulb.

First to use X-Ray technology, Sonar and Radar

His studies in high frequency and high potential wave theory led to micro wave and laser technology 50 years later for the star wars space weapons for locking on and destroying ICBM missiles.

Developed torpedo and missile guidance system for the US Government.

Pioneer in low frequency pulse theory that is the wave length that we communicate with submarines around the world by by send signals into the earth.

He developed the Wardencliff Tower which if were duplicated all over the world would give all nations free electrical power using the earth's magnetic flux to supply power from the earth itself. The prototype project was funded by JP Morgan and was shut down when Morgan asked Tesla where the meter would be attached. Tesla was a humanitarian and had no interest in commercial interests.

There are many other things that Tesla pioneered and developed and he had hundreds of patents which other persons and corporate interests made billions of dollars on. Once Tesla got one of his projects to a situation where he was satisfied with his accomplishment, he would become bored and moved on to the next interest. He was showered with benefactors and money his entire adult life and was only interested in science and his quest for more understanding.

If you research his name before 1980 you will find very little info other than the coil and AC Power thing because he and George Westinghouse won the power distribution war between AC or DC being the standard for the power industry. They went up against the biggest financial and industrial people in the world who were invested in DC. After their loss they made every effort to buy out and ruin Westinghouse and destroy Tesla from history because of their control in publishing.

Today with the internet, the hold on Tesla's accomplishments and blackballing is not as big of a barrier to his legacy. There was also a raciest factor involved because Tesla was from the mountains of Croatia.

When Tesla found out that his good friend George Westinghouse was losing his company because of the fat cat rat fink Kabul lead by Thomas Edison, Tesla ripped up his royalty contract so Westinghouse would have the capitol to fend off the stock takeover. He did this for his friend and the person who believed in Tesla's vision concerning Polyphase AC power distribution when it was just a dream.

That contract that he ripped up was the largest contract in world history to the benefactor of the royalties. Tesla owned a contract that would have made him the richest man the world could have ever produced because is was to received 1 dollar for every 1 horsepower of any item built using or generating AC as a source. This was at the begining of the industrial revolution. A pretty good friend I would say.

Some of the great minds in academia did some studies that were double blind evaluations that took place at Stanford, MIT and Princeton concerning the statistics relative to Tesla's contributions and impact on humanity as a scientist and inventor. The odds of one man making the type of contributions he made was astronomical and a mathematical impossibility.

On all three of the surveys seeking mathematical and statistical input from the top minds from academia the results all came back with the same conclusion. Tesla was a Superman and because of the numerous advanced world and culture changing technologies he gave to human kind, you could not rule out the notion that he was not an extra terrestrial.:nono:

Rick

Check out this video:
http://www.youtube.com/watch?v=eoY_7mbm5ng
 
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Hi,
I hope the OP excuses this highjack but I have been a Tesla fan since I was 13 years old:

Nope don't mind at all.... as long as it isn't some BS flame war. This has been an interesting thread to read.

I wrote a paper on Nik Tesla years ago in college. Fascinating how many inventions that guy came up with that are the basis for many things still used today. Everyone's heard tons of stuff about Einstein but Tesla's name is virtually unheard of except for maybe the Tesla Coil.... and he might have been more brilliant.
 
Joey,

If you try the experiment I described, you will understand. There is nothing more to say.

Darrin's cue is super stiff. My cue with the .980 A Joint is as stiff as an Omega DPK with the big phenolic threaded deal and fat A Joint. Fact with no histrionics or mysticism.

Rick

OK, I will Rick.
.850-.980 to 1.250.
Let's do the math.
.950-.850/12, that would be .0108 per inch straight taper.
Much less angle than the usual .014 per inch taper. We're losing .038 in the A-joint area.

How do we go from .980 to 1.250 in 17 inches ?
A curve or parabola ?
How does the handle become skinnier when that averages close to .0159" per inch. If there is a curve, it will be very drastic from the .980" point to that curve to be able to keep the grip area slim.
Do you have a radius or curve? At what point ?

I got plenty of cosmetic blems heavy maple dowels. But, at .980" a-j area, I'm guessing I will have to add a lot of weight under the pin to counter that light middle and heavy bottom.
 
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