Tapering. CNC vs lathe...

scdiveteam said:
Hi TW,

Pivot point on the tip side reveals a solid cutter engagement from end to end. No sanding with 100% repeatability.

Examples:

By using machine based micrometer set points to adjust the joint side of the bar up or down, the following numbers are germane.

13 mm to .850 joint to tip is a measured differential of .339

12.75 mm to .850 is .348.

[...]
Click to expand...

1) Pivot point or no pivot point, if the shaft is oversize at all points there will be a "solid cutter engagement" anyway. The necessary and unwise pivot point plays no role in determining cutter engagement; any taper bar will ensure such engagement if the shaft being cut is larger than the finish cut.

2) 13mm = 0.5188". 0.850" - 0.5118" = 0.3882". You're off by almost a full 0.001", which I'm told matters.

3) Far more importantly, the differential built into a taper bar needs to be HALF of those values, relative to the angle of a taper bar. That information is undoubtedly contained in Joe Barringer's DVDs, and Dennis Diekman's videos, so I'm kind of surprised you didn't know that.

None of this most recent post of yours in any way validates using a pivot point on a taper bar to allow multiple profiles. If you think it does I'm very interested in hearing how you think that is so.

TW


 
You probably want to make multiple cuts on your shafts so a CNC is the way to go. You can control the taper anywhere along the shaft.

You don't need 4-axis. You need a variable speed to turn the shaft. You go slow. About 300rpm. You will need to adjust the turning speed, the feed rate to the spindle and cutters.

A variable speed spindle would be nice but not necessary. 20K is OK.

I built an XY CNC taper lathe in the 70's and it served me very well until I retired.

Taper bars are an old solution and are difficult to adjust for various cuts.

Bill S.
 
I feel pivoting the shaft changes the taper more on a pro taper bar set up than moving the dead center. For instance with a 13mm tip to change to a 12.5mm tip it might move the straight part of the pro taper from 13 inches to 12.5 inches. That will hardly be noticeable, but pivoting the joint end over would give a slight angle to the stroke area, but it may not be all that noticeable either with only .5mm difference. But bump that up to one or two mm difference and moving the dead center would definitely be the way to go.

No one has stated that the obvious fact that one shaft taper bar takes the place of about 10 to 20 computer programs. Because it takes a different program for most users for each shaft pass session that is put on. CNC is definitely more versatile, but is it really easier in most cases???
 
cueman said:
No one has stated that the obvious fact that one shaft taper bar takes the place of about 10 to 20 computer programs. Because it takes a different program for most users for each shaft pass session that is put on. CNC is definitely more versatile, but is it really easier in most cases???
Click to expand...

One program per shaft profile is all you need and in my limited experience yes, it's much easier if you have a digital mind.

When I got my saw machine from Blud he also provided me with a bunch of programs. One for each stage of cutting. I had zero knowledge of CNC. I quickly realized that the programs were all the same and any one of them could be used for any cut (had they been useable code that is, I also quickly realized they were deeply flawed) by simply compensating the starting point of the X axis however far away you want that pass to be oversized. You can do this on the fly for whatever you're cutting be it shafts, handles, forearms or dowels. The only thing that matters is the profile.

JC
 
cueman said:
I feel pivoting the shaft changes the taper more on a pro taper bar set up than moving the dead center. For instance with a 13mm tip to change to a 12.5mm tip it might move the straight part of the pro taper from 13 inches to 12.5 inches. That will hardly be noticeable, but pivoting the joint end over would give a slight angle to the stroke area, but it may not be all that noticeable either with only .5mm difference. But bump that up to one or two mm difference and moving the dead center would definitely be the way to go.

No one has stated that the obvious fact that one shaft taper bar takes the place of about 10 to 20 computer programs. Because it takes a different program for most users for each shaft pass session that is put on. CNC is definitely more versatile, but is it really easier in most cases???
Click to expand...

One program and just different offsets would do from first taper to final pass.
If you had to write 8 programs for 8 separate 1/4MM passes, it'd be easy too.
 
JoeyInCali said:
One program and just different offsets would do from first taper to final pass.
If you had to write 8 programs for 8 separate 1/4MM passes, it'd be easy too.
Click to expand...



I use a spreadsheet.

I input the final dimensions in diameter and length into the sheet along with how much I want to remove in each cutting session by %.

The sheet outputs my g code needed to run the tapers. I just cut and past it to notepad and save the files appropriately.

I can plug in new lengths and diameters and instantly have the programs for all the taper passes.


Royce
 
JoeyInCali said:
One program and just different offsets would do from first taper to final pass.
If you had to write 8 programs for 8 separate 1/4MM passes, it'd be easy too.
Click to expand...

The other thing I realized very quickly as an infant cue builder is that in order to experiment with tapers to find what you like the work involved with a taper bar to do so compared to CNC is astronomical. I wonder how many cue builders who have never used CNC have a main shaft profile that they use not because they experimented until they were satisfied but because they got worn out and decided "that's good enough" or simply just copied the profile of someone else's cue they like playing with. That's why I decided I needed CNC very early on in my adventure. I can cut 10 shafts with 10 different profiles in less time than I can fiddle fart around with a taper bar and dial indicator to get just one cut to a profile how I want it. And that's exactly what I'm doing and it's fun. Of course in the end I will no doubt use only one or two of them in my cues but there's also the aspect of duplicating an existing shaft and CNC also makes that much easier.

JC
 
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cueman said:
I feel pivoting the shaft changes the taper more on a pro taper bar set up than moving the dead center. For instance with a 13mm tip to change to a 12.5mm tip it might move the straight part of the pro taper from 13 inches to 12.5 inches. That will hardly be noticeable, but pivoting the joint end over would give a slight angle to the stroke area, but it may not be all that noticeable either with only .5mm difference. But bump that up to one or two mm difference and moving the dead center would definitely be the way to go.

No one has stated that the obvious fact that one shaft taper bar takes the place of about 10 to 20 computer programs. Because it takes a different program for most users for each shaft pass session that is put on. CNC is definitely more versatile, but is it really easier in most cases???
Click to expand...

When I used mine I created one program and from that I created 3 other programs. I had a program to take shafts to a .700 taper, a .05 that took 2 passes at .01 and a .005., per side , .02 that took 2 passes at .005 per side and a .01 that took 1 pass at .005 per side. All I had to do was touch off my cutter on my dead center and move out half my diameter distance minus half the diameter of my dead center and run any of my programs and get any shaft size I wanted. No matter what stage I was in the shaft turning process.
 
JC said:
The other thing I realized very quickly as an infant cue builder is that in order to experiment with tapers to find what you like the work involved with a taper bar to do so compared to CNC is astronomical. I wonder how many cue builders who have never used CNC have a main shaft profile that they use not because they experimented until they were satisfied but because they got worn out and decided "that's good enough" or simply just copied the profile of someone else's cue they like playing with. That's why I decided I needed CNC very early on in my adventure. I can cut 10 shafts with 10 different profiles in less time than I can fiddle fart around with a taper bar and dial indicator to get just one cut to a profile how I want it. And that's exactly what I'm doing and it's fun. Of course in the end I will no doubt use only one or two of them in my cues but there's also the aspect of duplicating an existing shaft and CNC also makes that much easier.

JC
Click to expand...

More than would admit. I was lucky and had 5 different taper bars, all a little different. I tested all 5, multiple angles for each to yield the two tapers I liked the most and wanted to offer. Even then, I felt like I was constrained.

Taper bars are definitely outdated. They work but I'm not sure there are any taper bar characteristics that are better than CNC. One day...
 
JBCustomCues said:
When I used mine I created one program and from that I created 3 other programs. I had a program to take shafts to a .700 taper, a .05 that took 2 passes at .01 and a .005., per side , .02 that took 2 passes at .005 per side and a .01 that took 1 pass at .005 per side. All I had to do was touch off my cutter on my dead center and move out half my diameter distance minus half the diameter of my dead center and run any of my programs and get any shaft size I wanted. No matter what stage I was in the shaft turning process.
Click to expand...
That's pretty smart.
 
Joey, Having a CNC machine to do shaft tapering is the way to go.
You can do any custom taper you can program it to do.
You can re-taper shafts to smaller diameter tips holding the same profile.

Then add in all the other things a CNC can do and it just dont make sense to use something else ... unless you are locked into one shaft profile for all your cue work.
True ... you can have custom tapers machined into the taper bar of the TaperShaper machine that Unique sells.
Excellent equipment by the way!
Eric Iorgov (ei cues) here in Corpus Christi Texas did just that as he prefers a SouthWest taper over all others and had that taper machined into a spare taper bar by Unique Products.
But that gets expensive if you have more than one or two made.

I am still putting the Mini-Raptor I bought from George together.
I found the 36" model is just not enough travel for shaft work and am converting it to a 48" bed.
George has been great working with me to do this.
 
cueman said:
[...]
No one has stated that the obvious fact that one shaft taper bar takes the place of about 10 to 20 computer programs. Because it takes a different program for most users for each shaft pass session that is put on. CNC is definitely more versatile, but is it really easier in most cases???
Click to expand...

Actually, I thought I stated it when mentioned that a cuemaker could have millions of shaft tapers "in stock" with the memory a typical computer provides.

I get your point that you can use one taper bar for different diameter passes by simply adjusting your depth of cut, but I don't understand why you think different G-code programs are required to do the same thing(?) Just as you can adjust your "X-axis" to remove more or less material, I can do the SAME THING with my CNC machine.

On the front of the cross-slide (X-axis) on my CNC tapering machine I have a hand dial that has 200 index marks (every 1.8 degrees). That allows me to VERY precisely change the end diameter of any shaft program I have by exactly 0.001" by simply dialing in (or out) one index mark. In that regard it functions EXACTLY like your manual taper bar machine.

So if I wanted to I could run all my shafts, from raw blank to finished cut, using only ONE CNC program - just as you can do the same with only one taper bar.

However, CNC programs take up ZERO shelf space. If you already have a hard drive you have enough storage for all the existing shaft tapers on the planet - TIME 1000(!)

Changing programs takes but a few seconds, and for my own shafts all my programs are named numerically - "shaft1.nc", "shaft2.nc", "shaft3.nc", etc. Each time I take a cut on a group of blanks I mark them with a pencil, using just the number of the most recent program I ran on them. This makes it SO easy to keep track of the progressive cutting schedule that I literally NEVER check them with a caliper until I am down the very last few cuts.

So yes - for me, anyway - CNC is much, MUCH easier. If it wasn't, I'd still have my table saw rig and Jerry McW., um... wouldn't.

TW

 
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WilleeCue said:
Joey, Having a CNC machine to do shaft tapering is the way to go.
You can do any custom taper you can program it to do.
You can re-taper shafts to smaller diameter tips holding the same profile.

Then add in all the other things a CNC can do and it just dont make sense to use something else ... unless you are locked into one shaft profile for all your cue work.
True ... you can have custom tapers machined into the taper bar of the TaperShaper machine that Unique sells.
Excellent equipment by the way!
Eric Iorgov (ei cues) here in Corpus Christi Texas did just that as he prefers a SouthWest taper over all others and had that taper machined into a spare taper bar by Unique Products.
But that gets expensive if you have more than one or two made.

I am still putting the Mini-Raptor I bought from George together.
I found the 36" model is just not enough travel for shaft work and am converting it to a 48" bed.
George has been great working with me to do this.
Click to expand...
What happened to the Chinese cnc? You didn't get a longer version of it.
I'll wait for XZ's cnc lathe and mill.
 
Thomas Wayne said:


Actually, I thought I stated it when mentioned that a cuemaker could have millions of shaft tapers "in stock" with the memory a typical computer provides.

I get your point that you can use one taper bar for different diameter passes by simply adjusting your depth of cut, but I don't understand why you think different G-code programs are required to do the same thing(?) Just as you can adjust your "X-axis" to remove more or less material, I can do the SAME THING with my CNC machine.

On the front of the cross-slide (X-axis) on my CNC tapering machine I have a hand dial that has 200 index marks (every 1.8 degrees). That allows me to VERY precisely change the end diameter of any shaft program I have by exactly 0.001" by simply dialing in (or out) one index mark. In that regard it functions EXACTLY like your manual taper bar machine.

So if I wanted to I could run all my shafts, from raw blank to finished cut, using only ONE CNC program - just as you can do the same with only one taper bar.

However, CNC programs take up ZERO shelf space. If you already have a hard drive you have enough storage for all the existing shaft tapers on the planet - TIME 1000(!)

Changing programs takes but a few seconds, and for my own shafts all my programs are named numerically - "shaft1.nc", "shaft2.nc", "shaft3.nc", etc. Each time I take a cut on a group of blanks I mark them with a pencil, using just the number of the most recent program I ran on them. This makes it SO easy to keep track of the progressive cutting schedule that I literally NEVER check them with a caliper until I am down the very last few cuts.

So yes - for me, anyway - CNC is much, MUCH easier. If it wasn't, I'd still have my table saw rig and Jerry McW., um... wouldn't.

TW
Click to expand...
But, but, the table saw Tranformers cut the smoothest RMS in only 7 minutes for butts and 16 minutes for shafts . :grin:
 
Thomas Wayne said:


Actually, I thought I stated it when mentioned that a cuemaker could have millions of shaft tapers "in stock" with the memory a typical computer provides.

I get your point that you can use one taper bar for different diameter passes by simply adjusting your depth of cut, but I don't understand why you think different G-code programs are required to do the same thing(?) Just as you can adjust your "X-axis" to remove more or less material, I can do the SAME THING with my CNC machine.

On the front of the cross-slide (X-axis) on my CNC tapering machine I have a hand dial that has 200 index marks (every 1.8 degrees). That allows me to VERY precisely change the end diameter of any shaft program I have by exactly 0.001" by simply dialing in (or out) one index mark. In that regard it functions EXACTLY like your manual taper bar machine.

So if I wanted to I could run all my shafts, from raw blank to finished cut, using only ONE CNC program - just as you can do the same with only one taper bar.

However, CNC programs take up ZERO shelf space. If you already have a hard drive you have enough storage for all the existing shaft tapers on the planet - TIME 1000(!)

Changing programs takes but a few seconds, and for my own shafts all my programs are named numerically - "shaft1.nc", "shaft2.nc", "shaft3.nc", etc. Each time I take a cut on a group of blanks I mark them with a pencil, using just the number of the most recent program I ran on them. This makes it SO easy to keep track of the progressive cutting schedule that I literally NEVER check them with a caliper until I am down the very last few cuts.

So yes - for me, anyway - CNC is much, MUCH easier. If it wasn't, I'd still have my table saw rig and Jerry McW., um... wouldn't.

TW
Click to expand...
You could literally run your CNC just like a taper bar and never even have to know exactly where true zero is. Just dial in to where you want the starting cut and zero that axis and hit the go command. But that would be slower than just using a taper bar machine. On my CNC saw machine I use for shafts we do not have to touch off on anything, we just turn it on choose the program and hit 2 for run and hit C a couple of times to start and off it goes. It turns on the blades makes the passes and takes the 4 blades back to 2 inches from Zero and shuts off. It does a forward pass and return pass that is a little deeper. My son wrote a program for each session. So I look at the shaft taper and tip diameter and click on it and it is ready to go. So yes I understand the ease of using CNC.
I also own a 20 tool Magazine CNC Mill we use to build our lathe parts and I am not proficient at writing programs. I can turn it on and run a program and do some simple modifications to the programs, but I depend on machinists with more programming experience to write my programs for me. The same goes for our two CNC inlay machines. My son writes the programs for those. My point is the learning curve for CNC programming is pretty challenging and many people like myself would rather build cues than learn how to program CNC. So I do all my butt tapering on a manual taper bar machine and most of the shaft tapering on the CNC machine.
The experimental phase of shaft tapers is much easier on the CNC. But once you know what you want and get a taper bar set up that way for doing single shafts the taper bar is easier for me. But my CNC runs four at a time and I almost never turn my single shaft shaft manual tapering machine on anymore.
 
cueman said:
You could literally run your CNC just like a taper bar and never even have to know exactly where true zero is. Just dial in to where you want the starting cut and zero that axis and hit the go command. But that would be slower than just using a taper bar machine. On my CNC saw machine I use for shafts we do not have to touch off on anything, we just turn it on choose the program and hit 2 for run and hit C a couple of times to start and off it goes. It turns on the blades makes the passes and takes the 4 blades back to 2 inches from Zero and shuts off. It does a forward pass and return pass that is a little deeper. My son wrote a program for each session. So I look at the shaft taper and tip diameter and click on it and it is ready to go. So yes I understand the ease of using CNC.
I also own a 20 tool Magazine CNC Mill we use to build our lathe parts and I am not proficient at writing programs. I can turn it on and run a program and do some simple modifications to the programs, but I depend on machinists with more programming experience to write my programs for me. The same goes for our two CNC inlay machines. My son writes the programs for those. My point is the learning curve for CNC programming is pretty challenging and many people like myself would rather build cues than learn how to program CNC. So I do all my butt tapering on a manual taper bar machine and most of the shaft tapering on the CNC machine.
The experimental phase of shaft tapers is much easier on the CNC. But once you know what you want and get a taper bar set up that way for doing single shafts the taper bar is easier for me. But my CNC runs four at a time and I almost never turn my single shaft shaft manual tapering machine on anymore.
Click to expand...

Uh, I was just telling you what can be done with CNC and how it can emulate anything a manual taper-bar setup can do. In my own shop I NEVER change the "zero" positions. Every program is based on the same known initial "home" location.

And there is NO WAY a manual taperbar machine is faster than CNC. At every end stop you would either have to dial in the cutter head and reverse the travel OR pull the work away from the cutter and reset the carriage position - if you intend to make multiple passes that is. With CNC all that is already written into the code, and you don't have to even look at the machine until it's completely done, no matter how many passes you want to take..

TW

 
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Thomas Wayne said:


However, CNC programs take up ZERO shelf space. If you already have a hard drive you have enough storage for all the existing shaft tapers on the planet - TIME 1000(!)

[...]

So yes - for me, anyway - CNC is much, MUCH easier. If it wasn't, I'd still have my table saw rig and Jerry McW., um... wouldn't.

TW
Click to expand...

Don't forget that a hard drive that can hold a literal billion CNC programs is cheaper than a taper bar.
 
Thomas Wayne said:


Uh, I was just telling you what can be done with CNC and how it can emulate anything a manual taper-bar setup can do. In my own shop I NEVER change the "zero" positions. Every program is based on the same known initial "home" location.

And there is NO WAY a manual taperbar machine is faster than CNC. At every end stop you would either have to dial in the cutter head and reverse the travel OR pull the work away from the cutter and reset the carriage position - if you intend to make multiple passes that is. With CNC all that is already written into the code, and you don't have to even look at the machine until it's completely done, no matter how many passes you want to take..

TW
Click to expand...

If you know where your manual machine has been running you can dial in or out a few thousandths and hit the power switch and go. For single pass sessions there is: No turning on your computer, choosing the program and hitting the commands to run. Just flip a switch and go. So yes I think in some instances a taper bar is faster than CNC, but not in all instances.

Another benefit to tapering on a manual machine is when it cuts itself off there is no need to worry about your computer and driver staying on for who knows how long until you decide to use it again. The hand pushed return for a manual machine like I taper butts on is about 12 inches per second. That is much faster than any rapid return speed I use on any of my CNC machines.
 
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cueman said:
If you know where your manual machine has been running you can dial in or out a few thousandths and hit the power switch and go. For single pass sessions there is: No turning on your computer, choosing the program and hitting the commands to run. Just flip a switch and go. So yes I think in some instances a taper bar is faster than CNC, but not in all instances.

Another benefit to tapering on a manual machine is when it cuts itself off there is no need to worry about your computer and driver staying on for who knows how long until you decide to use it again. The hand pushed return for a manual machine like I taper butts on is about 12 inches per second. That is much faster than any rapid return speed I use on any of my CNC machines.
Click to expand...

Well by that rationale, if you have a light bulb burn out and there's a candle and a lighter nearby it's WAY faster to light the candle than go to the pantry, open the light bulb box, take out a bulb, close up the box, go back out to the lamp, turn it off and wait for the bulb to cool, unscrew the dead bulb, screw in the new bulb, and throw the old bulb in the trash.

But I'm still gonna use that light bulb every time. Call me silly.

TW

 
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