# Nose cone - ball turner (1st attempt)



## Divided He ad

Well here is the first attempt to make what I think is the right part? feel free to tell me otherwise. I wouldn't know if there are exact standards that should be adhered to. I just made what I think looks right! ;D

Ralph.

( be kind.... I know it's not perfect!! : )

[ame]http://www.youtube.com/watch?v=s_KRElCauTM[/ame]





			
				wdp67  said:
			
		

> Hi everyone,
> 
> How do you use a ball turner to cut more of a nose cone type shape? I built a ball cutter similar to the Bedair website over the weekend, but have not had a chance to try it out yet. I need to cut an ogive type shape and now am wondering if anyone can steer me in the right direction.
> 
> Thanks
> Walt
> 
> 
> 
> 
> 
> 
> 
> BobWarfield  said:
> 
> 
> 
> 
> Fellas, I'm still not getting my head around this one.
> 
> It seems to me that no matter where you move the axis, or what the radius is, the cutter is still going to describe an arc of a circle. Nose cones are more parabolas or elliptical unless I am confused about what is meant by a nose cone. I can't see how you get a ball turner to make a parabola or an ellipse.
> 
> The axis does need to move, but it needs to move along the axis, not perpendicular to it. Now if you could somehow engage the power feed and cause the pivot to be synced while moving the center of rotation from one ellipse focus to the next, you get an ellipse or segment thereof. Think of it as a taper turning attachment connected to a ball turner in some nefarious way. Some sort of cam connecting the power feed motion to the rotation of the ball turner would allow you to modify the nose cone shape. Better yet, a tracer attachment makes more sense. Alternatively, perhaps a talented operator could freehand the ball turner well enough while the power feed was engaged.
> 
> I did draw some examples in Rhino3D of what happens if you simply move the center of the turning tool and increase the radius. It cuts a torus, which may or may not be helpful. Assuming you don't dip into the flat spot on the end, I guess you can make a useful shape, but still doesn't seem like a nose cone shape to me.
> 
> OTOH, this is all in my head and I may be completely confused! LOL
> 
> Cheers,
> 
> BW
Click to expand...


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## Powder keg

Great stuff Ralph!!! I'll have to mount a camera on my lathe now. You can get some good video that way. 

Wes


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## Bernd

Very nice job. It's starting to make me want to build one of those ball turning tools.

Just a question; how hard would it be to make several so they look alike in size? I know the OD would need to be the same and the same goes for length. 

Bernd


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## Divided He ad

Bernd, firstly... build one!!! secondly, thank you ;D

Thirdly, it would be pretty easy I think! Once the tool is set to the required arc and you have locked the saddle, you just don't move it until all the required parts are made.
The arbour stays in the chuck and the 'pre-tapped and length adjusted blanks are screwed on.. polish them all after the cuts are completed. Why you would want multiple I don't know? I don't know what to do with this one... I only made it to take on the challenge! ;D

Ralph.




			
				Bernd  said:
			
		

> Very nice job. It's starting to make me want to build one of those ball turning tools.
> 
> Just a question; how hard would it be to make several so they look alike in size? I know the OD would need to be the same and the same goes for length.
> 
> Bernd


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## wdp67

Thats 100% what it was I was asking!! Awesome video, now can you kind of explain it a little please??

I assume you have it set up to cut a bigger arc than the diameter, and how did you determine where to put the tool to start out? Did you have to move the tool while you where cutting or was it in the same place for the whole job.

Sorry for all the questions, but I messed around all last night and had no luck, cut lots of ball shapes but no nosecone shape.

Thanks again for your help!!

Walt


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## AllThumbs

That part is more commonly called a spinner! Very nice.

E


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## Divided He ad

Hi Walt, I was expecting this ;D

 It's late so I'll try to Write this well and correctly before my face hits the keyboard!! :big: (seriously... it's nearly 2am! spent 8 times what it took me to make the cone editing and uploading the vid!!!) 

So here goes, I'm afraid it's a little Heath Robinson right now but it should get you on the right track... as I said it was my first go!

1/ I set the arc a lot larger than I would to make the ball. then test rotated it from the back of the work piece toward the front (see the vid... when the tool is in the forward facing position it's near the chuck end) 

2/ I wound the tool back so that when it was rotated it just contacted the front.

3/ start her up and start cutting, moving the tool inward in small steps (in the vid I wasn't quite in the correct position so you will see me correct it, you may need to do this too?... but only on the first if your making many?)

4/ the cone shape should start to form as in the vid, if it does not then you either have the tool too far from the chuck end of the work piece or the arc is too small ( I will try to work out a measurement setting for the dia of work piece and the tool setting tomorrow)

I have been using this tool for over a year and made a huge quantity of items for myself and customers, it will all become easier if you make lots of bits and experiment ;D 


I hope this helps? I'll put some better thought on it tomorrow morning when I can think! 


Ralph.

Ha! no spelling mistakes either... can't be that tired eh!?

P.S. here's a few of my customers pieces... just to show you where experiments get you.... all in stainless ;D


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## wdp67

Thanks a lot for the help, I really appreciate it!! I will let you know how it goes, heading out to the shop right now!

Walt


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## tattoomike68

Divided He ad  said:
			
		

> Well here is the first attempt to make what I think is the right part? feel free to tell me otherwise. I wouldn't know if there are exact standards that should be adhered to. I just made what I think looks right! ;D
> 
> Ralph.
> 
> ( be kind.... I know it's not perfect!! : )
> 
> [ame]http://www.youtube.com/watch?v=s_KRElCauTM[/ame]
> 
> Its perfect , we machinist strive to be artist and craftman. I like the music, we used to lock the doors and work saturdays and listen to celtic on NPR radio. It was quite peaceful to work to.


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## mklotz

The proper name for this shape is "ogive". It is formed from arcs of a circle which is why it's possible to turn it with a ball turner. The center of rotation of the ball turner must be placed off the central axis of the of the ogive.

An excellent treatment of the mathematics of the ogive is available here...

http://www.geocities.com/rocketguy_101/ogive/OgiveNoseCones.htm


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## BobWarfield

Ah so, said the blind man!

The ogive diagrams make it all clear: big radius (bigger than diameter of workpiece), center of radius on far side of spindle axis, convex ball cutting.

Thanks!

BW


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## Divided He ad

Can't wait to see your results Walt, your question is the only reason I tried this one out 

Thanks Mike, and glad you like the tune 

Marv... that makes my head hurt! ??? ( but is going to be read in little bits!)

BW, I think your thanks are to Marv? but I shall say no problem either way! ;D (Am I to understand that you understand the stuff Marv linked to?... if so... Wow!)


Ralph.


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## mklotz

Ralph,

Now you know what I'm talking about when I use the phrase "shop math".  It looks complex at first glance but it's just simple algebra and trigonometry. Stick with it and all will become clear.

For those who haven't yet built a ball turner, the OGIVE program on my page will produce an incremental cutting schedule (similar to the operation of BALLCUT) suitable for non-critical-dimension ogives.


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## Divided He ad

Thanks Marv.... I failed maffs (as we call it here!!) couldn't get my head around algebra!! and to be honest haven't used trig etc for so long it's all but gone!! ??? (I've been fixing cars... don't use many sums for most of that.... just a hammer ;D )

I'll persevere though. Some day I'm going to have to make something that requires it ?!?

Ralph. 

P.S...... holy @#*% Marv... just looked at your web site and read your little bio' ... no wonder you know your math!! ;D


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## wdp67

Well I tried it again last night after watching your video, and I had some success!!

I got family stuff happening today, so tommorw I will try to get some pictures posted. Thanks again for all the help, could not have done it without you!!!

Walt


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## BobWarfield

Divided He ad  said:
			
		

> BW, I think your thanks are to Marv? but I shall say no problem either way! ;D (Am I to understand that you understand the stuff Marv linked to?... if so... Wow!)
> 
> 
> Ralph.



That math I can still do, LOL. I'm sure Marv goes past my pain zone though! It wasn't the math that got me there, it was the diagrams showing the radius in relation to the workpiece and curve.

Incidentally, those equations, an Excel spreadsheet, and just a little effort and you could get the results Marv's program outputs on depth of cut for each position. Or, with a little more effort and cleverness, that Excel spreadsheet could generate the g-code to do it on a CNC automagically.

Cheers,

BW


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## Divided He ad

No problem Walt, was glad I could achieve what I thought I could! ;D 
Waiting to see your pics, will make sure I check tomorrow 

BW, Even if I could do all that with the spread sheets etc (which I have never tried!) I sure know I could not afford the cnc equipment! 

Question: Do all you fellas who 'cnc' still get the same satisfaction from creating a program and seeing it run as you would if you used your head and hands to manually power the machine into creating a similar part? ( I know the advantages of precision and awkward part creation, but still....?)

Just wondering, Ralph.


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## bentprop

Nice job,Ralph.But i hope those spinners are not going on a flying aeroplane.
With that point you can split someone's head in two ;D.Looks great,though.
Did you use aluminium or steel?
That ball turner is definitely going on my "to do" list.


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## Divided He ad

Hello Mr Bentprop (didn't leave a name!) Thank you, and no my spinner has no home at all, it was just to help out Walt (wdp67) 
I listed the materials in the credits... no one ever stays till the end!! ;D

Bright mild steel.

The website for the plans is also listed in the credits! 


Ralph.


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## Bogstandard

Ralph,

This post is getting better and better.

I am sure a few of the members on here always wanted to make a ball turner, but had really no idea for the correct use or what they can achieve with one.

Now we are all learning how it is done, and model engines will benefit from it all.

I must admit, my ball turner very rarely gets used, I tend just to hack things out with a graver and files, but that will all be changing soon.

Well done.

John


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## Bernd

I downloaded the plans. So when I get my two wobblers done : I'm starting on some much needed tooling and a ball turner is on the list. Don't exactly know where on the list, but it's on there. ;D

Bernd

P.S. Ralph, that lathe looks simular to a Grizzly 9 X 20.


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## Divided He ad

Thank you John, and yes if you got one use it ... it's probably my favorite piece of kit  (that attaches to the lathe!)

Bernd, 

Make it soon... you won't regret it ;D and yes my lathe is a 9x20 'Chester UK' variation. It has some of the faults known on these machines but it works and always seems to come through! (even if the tailstock lock just bust!! More work!! : )


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## Seanie

Thanks Ralph, they say a picture is worth a thousand words- a video must be worth half a million!

Excellent & inspiring


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## d-m

Hi all 
I built a ball turner over a year ago and have use it several times now. But only I seem to only be able to make is an ogive cant quite get a ball ??? maybe next week I will take it off the shelf and give it a nother try. Marv I would like to know what you have frogotten over the years. Ralph I'm with you on that one after 30+ years under the hood you forget the math because it makes your head hurt just like your back.
Excellent post in joyed every bit of it !!!!
Dave


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## Divided He ad

Thank you both, 

Dave. There is a ball turning post or two out there too, if your ball turner is the same type as mine I can help you set it up to cut a near perfect ball.. this is the ball turning post I did a little while ago... 

http://www.homemodelenginemachinist.com/index.php?topic=1633.msg12860#msg12860

Hope this helps?  



Ralph.


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## mklotz

d-m  said:
			
		

> Hi all
> I built a ball turner over a year ago and have use it several times now. But only I seem to only be able to make is an ogive cant quite get a ball ??? maybe next week I will take it off the shelf and give it a nother try. Marv I would like to know what you have frogotten over the years. Ralph I'm with you on that one after 30+ years under the hood you forget the math because it makes your head hurt just like your back.
> Excellent post in joyed every bit of it !!!!
> Dave



Hell, I'd like to know what I've forgotten over the years.  If you're having problems turning a true sphere, it's most likely because you haven't ensured that the axis of the ball turning tool is aligned with the lathe spin axis. The vertical axis of the tool must intersect the horizontal spin axis of the lathe.

When I made my ball turning tool, I arranged for the pivot to have a central hole on the axis of rotation into which I could fit a pointed rod. The tip of this rod is then aligned with the tip of a center mounted in the spindle, thus guaranteeing that the two axes are aligned. Then the pin and the lathe center are removed, the work mounted and turning begun.


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## d-m

OK guys I'm going to dive into this one head first and see what happens. Here is a pic of the turner I made when I first got my mill. As you can see by the handle it makes a nice Ogive ( I love nomenclature and spell check) I have most of the parts for a turner like the one Ralph has just haven't had the time to finish.This turner I found on the web somewere and thought it was a good project it is vary stout to say the least. My Sterling fan is killing my hobby time so I haven't gotten back to it . If I understand what Marv is saying its just a matter of getting the cutting tool at the right height? I also see the advantage of having a mandrel to put the work on. OK guys hit me with some help I will go to the shop and see if I can make it work better. 
Dave


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## Divided He ad

Hi Dave. 

I can't see how you adjust the tool? if it is fixed then it will only turn one size of ball! what is the distance from the tool tip to the (imaginary) line of the centre of the main pivots ? this is the radius of the ball size it will cut... thats as far as I can make out?! I have never used this kind of tool but thats what I can see from ur pic's ???
feel free to tell me I'm speaking #@%* anyone... I certainly don't know it all ;D 

Ralph.


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## Mcgyver

yeah the incremental cut method works very well, so well that I've never gotten around to making a ball or radius cutting tool. Granted the radius cutting tool would be quicker and more accurate, but I've found this activity to be both infrequent and low precision (not mating parts) - knowing how to do it without the ball turn sure takes away a lot of the motivation to make one . For the unfamiliar, the curve is approximated with small steps, MNC instead or CNC (that's Manual Numeric Control). The steps are easily rounded with a smooth file followed by some emery. Its nice if you have a graduated leadscrew dial (another good project) however using the compound would also work.

The excel table i use is attached if you're interested - it gets used infrequently enough that i had to leave myself instructions so I'd know how to use it next time, hopefully it makes sense to you.  

View attachment Mcgyver\'s ball turning calculations.xls


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## Bernd

Mcgyver  said:
			
		

> For the unfamiliar, the curve is approximated with small steps, MNC instead or CNC (that's Manual Numeric Control). The steps are easily rounded with a smooth file followed by some emery. Its nice if you have a graduated leadscrew dial (another good project) however using the compound would also work.



That's the method Guy Lautard has in his Bedside Reader. I have his little book with tables in it to turn balls from 1/64" to 1" in 64th's increments. Also has instructions for concave turning, plus making machine handles. Very informative. Haven't used his method yet. Too lazy I guess. ;D

Bernd


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## mklotz

Seems a bit of confusion about what I said. Let me try it another way...

To cut a true sphere, the axis about which the ball turning tool rotates must intersect the axis about which the work turns (this latter is the spindle axis if working on the lathe).

In Dave's (d-m) photo above, the former axis is the one to which the operating handle is attached.

As Ralph has pointed out the radius of the ball is determined by the distance between this axis and the tip of the cutting tool.

Like McGyver, I prefer to turn most balls using the incremental approach. My BALLCUT program will do all the math for you and produce a cutting schedule which you can print and carry to the shop. For me, it takes less time to do it incrementally than it takes to set up the ball turning tool.

Once you've made all the incremental cuts, slather the workpiece with Dykem (layout fluid for our British cousins). Then file until all the Dykem color disappears and you'll have a very nice sphere.

Incidentally, my incremental OGIVE program works the same way to produce a cutting schedule for ogives. Like spheres, ogives seldom require precision sizing (most are for appearance only) so the incremental approach is more than satisfactory and a lot quicker.


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## Mcgyver

> That's the method Guy Lautard has in his Bedside Reader.



yup, great books they are. I gave credit to Guy as the inspiration in the excel file 

While on the subject of ball turning here is another really neat way to do so. This is better suited for wood or soft metals as it involves hand holding the tool. Absolutely perfect for making wooden ball handles....like I did on my UPT.

what you do is take a lenght of gauge plate, (tool steel, same as drill rod) maybe 1/8 thick and drill/bore a hole in it some amount less than the desired OD of the ball, maybe for a 1" ball make a 5/8 or 3/4 hole. You want a neat edge between and where the hole meets the flat surface of the plate - this is the cutting edge. removed sharp edges or better yet duct tape the end(s) thats the handle. No need to harden for use on wood. Rough out the blank of say hardwood and simply hold the hole in the gauge plate to the work and move it around.  The edge of the hole will remove high spots until the work perfectly touches the gauge plate all around the edge of the hole - and when that happens you've made it a sphere!


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## Divided He ad

Well I know that everyone is different and all of us will have our preferred methods of cutting both sphere's and ogives... But I like mine.   :big:

I would really like to see someone make a sphere using the incremental method though... If anyone has the time to film and present it? Would also like to know the time taken to perform the task? ( maybe a knob/ball around 5/8 to 3/4"? ) 

Is anyone able to complete such a mammoth task!?!?! ;D


Ralph.


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## mklotz

Ralph,

I don't have time to do a video but why don't you try it for yourself. Mount some 3/4" stock and a cutoff tool with a square tip. The cutting schedule for a 3/4" hemisphere is given below. Start with the left side of the tool against the (faced off) surface of the stock.

When you've completed the cuts, coat with Dykem and then file until all the Dykem disappears.

There are 17 cuts to make. Figure 15 seconds per cut and that's, rounding up, five minutes to make the cuts. Add another ten minutes for filing and you should be done in fifteen minutes or so.

For a more detailed discussion of the technique and the method for cutting full spheres, read the text file included in the BALLCUT archive.


===================================================

Incremental Sphere Turning Data
Sphere diameter = 0.7500 in
Stock diameter = 0.7500 in
Angular increment = 5.0000 deg

N = cut number
XF = axial (along lathe bed) position of tool
DX = increment in x from last cut
YF = depth of cut
DY = increment in y from last cut
WD = work diameter resulting from depth of cut YF

 N    XF    DX    YF    DY    WD

 0  0.000  +0.000  0.375  +0.000  0.000
 1  0.001  +0.001  0.342  -0.033  0.065
 2  0.006  +0.004  0.310  -0.032  0.130
 3  0.013  +0.007  0.278  -0.032  0.194
 4  0.023  +0.010  0.247  -0.031  0.257
 5  0.035  +0.013  0.217  -0.030  0.317
 6  0.050  +0.015  0.187  -0.029  0.375
 7  0.068  +0.018  0.160  -0.028  0.430
 8  0.088  +0.020  0.134  -0.026  0.482
 9  0.110  +0.022  0.110  -0.024  0.530
 10  0.134  +0.024  0.088  -0.022  0.575
 11  0.160  +0.026  0.068  -0.020  0.614
 12  0.188  +0.028  0.050  -0.018  0.650
 13  0.217  +0.029  0.035  -0.015  0.680
 14  0.247  +0.030  0.023  -0.013  0.705
 15  0.278  +0.031  0.013  -0.010  0.724
 16  0.310  +0.032  0.006  -0.007  0.739
 17  0.342  +0.032  0.001  -0.004  0.747
 18  0.375  +0.033  0.000  -0.001  0.750


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## Bogstandard

Ralph,

No-one is disagreeing with your ball turner at all, just showing that one isn't totally necessary. For repeatable jobs, a ball turner is great, but there are methods that have been used for centuries that give rather acceptable results. This is what the forum is for, showing how you do it, it would be unfair if other people couldn't show their way as well.

I have a ball turner that uses my milling boring head, but find, just like Marv I tend to do it freehand.

This set of pics is for a funnel cap I did recently on another site, not balls or ogives, but curves just the same. The only reason for the mandrel was because it was made out a left over lump, normally it would have the first parts done on the end of a piece of bar.

All that was used for making was the machine cutting tools, to give the basic shape, a second cut, half round file, an emery block and a good dose of polishing. About 3/4 of an hour to an hour total.

I do all my ogives this way, 2" or 3" would present no problems at all, 1/4" done in seconds.




























































Rather difficult to do with a ball turner.

John


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## BobWarfield

This is a fun thread. Smooth flowing shapes really catch the eye. 

Of course, this is the sort of thing CNC excels at too!

Cheers,

BW


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## Divided He ad

Gents, please don't get me wrong... All that I write is intended with a touch of humour, hence the  and :big:

I intended no ill feelings toward anyone of you or your methods, I am not saying anyone or any method is better or worse. You must know by now I am in awe of many of your talents. My point was that I would like to see a vid of this method being applied (curiosity... learn new stuff!).

I get this kind of response sometimes using text messages?! Sometimes they are read a bit differently and in a different frame of mind to that in which they were written... ? 


I will have a few experiments at Marv's suggestion once my shop is erm shopshape!? 
and I have cleared a little backlog of requested work. 

I do like that piece John, Very smooth  I like the expanding arbour holder device. That could be useful! Did you cut the inner shape in the same way or by eye? 


Written by a happy guy.... (I am always happy when I am doing anything to do with machining).


Ralph. ;D 

Oh and BW... If you get a chance with CNC that would be a fun vid/post too! ;D


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## mklotz

At the risk of beating the subject to death, let me say that the incremental method closely approximates the way that CNC works. In fact, I call it HAM - Human Assisted Machining.

As such, it can be used for any shape including those that can't be generated via a simple mechanical motion imparted to the cutting tool.

In fact, I wrote a program, PROFILE, that allows one to describe a shape via a data file and the program will generate a cutting schedule (similar to those for BALLCUT and OGIVE). In addition to the standard straight line and arc descriptors it also has the ability to fit splines to a series of points to achieve a more artistic blending. I used this program to make the three ball handles on the PMR lathe model.

Nevertheless, I wish I had the sculptor's eye that John and others seem to have. I've turned some simple free-form shapes by hand with a graver and it's a lot easier if one has the dexterity for it. For larger shapes, I still rough it out incrementally because that gives me the basic shape that I want (and that my hand can't seem to generate). Then filing and sandpapering produce the final product.

Different strokes... My advice is to try all the different methods at least once or twice and decide what best suits your complement of skills and equipment.


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## Bogstandard

Ralph, 

Sorry if I upset you, I wasn't getting on at you at all.

Back to the funnel cap.

There is in fact a shot I never took, well I did, but is was too blurred, and that was showing me using a boring bar to get the inside shape to rough dimensions, as I did on the outside with a normal cutting tool. By using a caliper type of finger and thumb feel you should be able to tell whether it is close to the outside shape. Again my motto is, if it looks right, it is right. No measuring, except for the funnel fit. 

Try it, it is so simple, but be very careful of the knuckle crunching chuck jaws, that is why I use my collet chuck for most work like this, it is a lot safer.

John

John


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## tel

A variant of Mcgyver's scheme is to use wad punches to swizzle the roughly shaped lump into a ball - especially good for smaller ones, I use 'em all the time.


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## Cedge

The more tricks and tips presented, the more flexible we all become as we encounter a tricky bit of challenging metal work. It definitely encourages mentally stepping outside of the box and increases one's comfort zone. 

I not only have a ball turner... I built 3 different styles, basically because I was curious enough to want to see how each one performed. They are convenient for what they are and lots of fun to build and to use.

Having said that, I also use incremental cutting, freehand gravier, hand files, loads of sandpaper and now I'm beginning to adopt form tools. The point is that I use whatever works when the circumstances dictate it. I never wonder if it's what the pro's do and I don't worry if it's the "right" way. As long as everything stays well within the safety envelope, there are no barriers.

Heck.... I'll use just about anything that will get me to where I want to go. The family cat still hasn't forgiven me the day that I needed a small sable grade paint brush... even though the bare spots on his tail are long gone.

Keep sharing the techniques that work for you and I'll keep filing them away in my head until they are needed. That loud sucking sound, heard on the HMEM board, is made by us newbies absorbing all the great information this place makes available.

Thanks from all us newbies...
Steve


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## Bogstandard

Tel,

A man after my own heart.

Swizzle, the perfect word for it. 

If there isn't a word available, make one up that describes the action.

John


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## mklotz

I think the (very minor) problem is that, if someone posts an alternate method without an introductory disclaimer (e.g., this is how I do it), it's easy for the OP to get the idea that we're criticizing his approach rather than embellishing the presentation with alternate ideas.

I know I'm guilty of this and I'm trying to sensitize myself about it but it still slips through. When I respond I'm thinking of all the folks who might read this in the future and trying to make each thread a smorgasbord of suggestions for those folks.

So, be advised to turn down the sensitivity on your annoyance filters. If you read my posting history, I think you'll see that knocking other people's way of working is the last thing on my mind. Furthermore, I suspect that's true of most of the other people who post here.


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## Cedge

Aww Marv...
We all know you aren't one for getting anyone's goat. It's just the nature of communicating with typed words instead of normal speech. What is written meaning to be humorous often gets misconstrued. We all enjoy having you chime in. Things only gets out of hand if a couple of alpha males both want to pee on the same bush.

My shop wouldn't be half as much fun without your ingenious gadgets and being somewhat math challenged, I'd be completely lost without your calculator programs. I, for one, look forward to seeing a Marv post as much as a Bogster, Mcgyver... et al post. I'm always sure to learn something.

Steve


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## Divided He ad

Well all is now calm on this post!! I don't know you leave a simple video post a few weeks back and then all hell breaks loose!! :big:
No one upset here John  Just wanted to clear up any missconceptions : 

I love it, so many new things to try, so many things to try to remember!! How will I ever make all the things in my head?! Not to mention all the things from your heads! Where will I find the time? (that's in general, not just balls... and ogives!   )


It's all good ;D 


Ralph.


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## wdp67

Hi all,
I finally got some time to take some pictures of my ogive's that I needed to cut. Thanks to all of you for your help and especially Ralph for really taking time out to give me a hand.

Thanks
Walt


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## Divided He ad

Nice curves Walt! ;D 



Now you know the next curiosity question... What are they? ???
If it's top secret no worries. I'm happy That your happy 


Ralph.

P.S. Unless you are talking to us through time?! I think your camera is a little out on it's date :big:


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## BobWarfield

Actually, the CNC method does NOT resemble the incremental method at all. The tool path will follow the profile on CNC, more like what a ball turner does, or as a better example, what a hydraulic tracer does. There will be no "cut this little 1/8" to this depth and the next one to this depth and so on" with CNC. This is one reason why CNC guys are so uptight about backlash. Imagine the profile goes in and then back out, all the while continuously cutting. What happens to the backlash?   Oops, now your part is wrong.

Not that there is anything wrong with incremental, just wanted folks to be clear on how it works in CNC. FWIW, I have done the incremental before. This is an easy thing to lay out in Excel to get your schedule of cuts.

It works great, but I did find it to be kind of monotonous. Consequently I prefer to use tapers with limited radiusing with a file for a lot of my machine knobs:






That sort of thing goes really fast! I am pleasantly amused at how nicely a little lathe filing can turn out, particularly if you're turning 12L14 or something very free machining.

Cheers,

BW


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## zeusrekning

The incremental cylcle is similar to the G71 Roughing cyle. It roughs out the shape with steps then it then makes a pass that is the final shape.
Tim


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## wdp67

Thanks Ralph!

Can't really tell you what they are, but they will be used as a training aide where I work when finished. Now I just need to take some time and make a nice ball turner. I just threw this one together out of some junk I had laying around, just to experiment with my project. 

Turns out the finished ones where a big success at work so I will probably be making a whole bunch of them(maybe hundreds $$$) 

Thanks again!!

Walt


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## Divided He ad

No worries Walt... Nudge, nudge, wink, wink, say no mowarh!!  ( tis hard to type in a monty python style!!)

I'll post a pic of a little mod I finally did on my turner that I've been meaning to do for months. Not right now, got to walk up a mountain (well a big hill!) but will post it later, simple but very nessersary I think! ;D


Ralph.


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## Divided He ad

This was so simple and obvious from about a week after I made the tool but it took me ages to get around to it!! :

It is just a recess 0.3mm depth into both sides of the cutter carrier. The cut is 6mm wide and was set to remove the grubscrew marks that were in the tool, ensuring that the grubscrews would bite within the recess.











It simply stops the cutter carrier getting tight in the turret... doesn't sound like much but a few little burrs from the grubscrews and it's very difficult to remove or adjust the carrier. 

-----------------------------------------------------------------------------------------------------------------------------------------

Just one more thing to try to help Dave (and anyone else) with alignment issues. I know it's a different tool but this is how I set this tool up, I think the principal would be very similar? (might explain my question about his cutting tool adjustment too?) 





> Hi all
> I built a ball turner over a year ago and have use it several times now. But only I seem to only be able to make is an ogive cant quite get a ball  maybe next week I will take it off the shelf and give it a nother try. Marv I would like to know what you have frogotten over the years. Ralph I'm with you on that one after 30+ years under the hood you forget the math because it makes your head hurt just like your back.
> Excellent post in joyed every bit of it !!!!
> Dave



*This is to cut a ball not an ogive!*  









1) scribe a line through the centre of the main turret. (scribed lines to be permanent)

2) using a square, mark exactly the point from the tip of the tool onto the top of the tool carrier (see picture) and then using the square scribe a line across the carrier. You only have to do this once.. It must be accurate! 

3) using your vernier calipers set the distance between the two lines of the turret and carrier to half the dia' of the workpiece.( I know that's called radius but I'm trying to say it as I do it!)

4) set the tip of the tool to just touch the end of the workpiece, lock the saddle, wind the crossslide back clear of the workpiece and you are ready to start cutting. Slowly moving the cross slide back in toward the workpiece as you rotate the cutter around the radius until your ball is created ;D .





I do a lot of pieces from the same dia' steel so I put a little extra line on for quick alignment  














C'est voila!! 1" stainless steel screw on Knob ;D


Hope this helps... I don't think there is anything more I can add to this post in the way of help with your balls ?!  


Ralph.


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## d-m

Hi Guys 
Finely got back to reading the post on this wow I have learned a ton (again ). Marv I like the way you align the tool I will try to incorporate that in my turner vary simple solution as my dad allways said KSS (keep it simple stupid!) Ralph if you look at the first pic I adjust the cutter with the set screw up and down the shaft, there is a flat milled top to bottom I believe that's what you were looking for? I can see now some of the reason's this tool is not performing as I had hoped . And one is because it is fixed at the pivot points. At the time I made this I had no ideal that would determine the size of the ball, it hit me like an Iron skillet in my wife's hand after reading that. I am re thinking this completely. As soon as time allowes I will finish up the one I have started that is similar to yours Ralph. Thanks to all who posted. there is much needed Info here for a newbie. I will keep you posted ???
Dave


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## Divided He ad

d-m  said:
			
		

> Ralph if you look at the first pic I adjust the cutter with the set screw up and down the shaft, there is a flat milled top to bottom I believe that's what you were looking for?



Dave, 


Unless I'm missing something here (entirely possible!! ??? ) Wouldn't the Z axis adjustment you describe would only aid in setting tool centre height? 
I was trying to see where the X axis adjustment came from? The cutting tool looks too short to be extendable? 
If it cannot be lengthened or shortened then how can you adjust the arc for the tool to cut along? I could only imagine it cutting a very limited size range? 

On Steve Bedair's tool the arc is adjustable by altering the gap between the swivel axis and the cutting tip (hence the lines scribed onto mine)

I don't want to be seen as a screaming loony on this subject (too late they say!) I'm just trying to understand your tooling to try to aid in it's use  


Ralph.


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## d-m

Hi Ralph 
And that is the biggest set back is that there is no X axis adjustment except for moving the tool in and out of the holder longer tool smaller ball. 
I cant find the web page I copied the tool from but I did find this one below,as you can see the too has to holes in the bit holder for what I would think is 2 size ball's? Like I said I learn some thing all the time here !!!!!! I was thinking last night that if it was mounted to the cross slide set at 90 it would make a larger ball but this morning I realized that buy doing that you still haven't incrested the distance from the axes. So this tool of mine is a good tool but vary limited to size of ball you can turn ?????????? 
Dave
Ps 
your not looney ;D

http://www.nucleus.com/~harlan/ball.html


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## d-m

One more thing of intrest for you to look at I like the scale on this turner nicely done



http://bedair.org/9x20camlock/Bob.html

Dave


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## Divided He ad

Dave, 

If you look at the tool on Harlan's site you can see what I was thinking of... the tool is passed through the centre of the Z axis, so it can not only be moved between the two sets of grubscrews but the tool length itself can be altered using it's grub screw. 
Just a little rethink and I am sure you could have yours adjusting in this way?  

The scale on Bob's tool is very neat, I saw it a while ago but decided that it was unnecessary (for me) since I am so use to using my calc' and digital vernier to split the dia' as exactly as I can (not to mention I haven't got a rule narrow enough!). I know it is not always necessary to try to be so accurate but I always challenge myself to obtain the target sphere ;D 

Just looking back at Steve's site I remembered how much I altered his design myself, I have a much thicker baseplate, a double recessed shoulder for the turret for greater rigidity and My own cutter idea... It's good to rethink now and again 


Ralph.


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## CrewCab

Ralph'
Got to say I've really enjoyed this thread, your "spherical" turner is great ;D ......... once I have the means it's one of the first projects on my list 

Dave


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## Divided He ad

Thank you Dave (CC).

It has been fun trying to figure out how to express the set up processes etc. I bet some people have read it twice and still wondered what the hell I'm blathering on about... I know I have! :big: 

The tool is not mine Dave... It is the very selfless Steve Bedair's... I just borrowed it!! ;D His instructions are very easily followed, I made most of it before I got my mill' and then finished it of very excitedly when that arrived  

When you make yours You'll be a happy man ;D


Ralph.


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