# Spirals



## JimGo (Feb 15, 2005)

How do you turn a spiral?  I saw a pic in WoodScavenger's pics that included a spiral shape in the outside of the pen, and can't imagine how to do this other than by hand (for example, as Tom McMillan described here http://www.penturners.org/forum/topic.asp?TOPIC_ID=3564).  Does anyone have any suggestions?  Obviously, this is a bit beyond my current capabilities, but I hope to get there some day!

Any ideas are appreciated!


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## btboone (Feb 15, 2005)

CNC is a good option.  []  Actually doing it by hand would not be so bad if you had a super slow speed on the lathe, something like 30 rpms.  Short of that, filing by hand as the pen is turned by hand like Tom does it is the best way to go.  Another technique that's possible but may be tricky to get nice results with is the beadblaster option.  Also, metal lathes have threading capabilities, but I don't think most of those would go to such a long pitch.

There may be a way to wrap a flexible turning guide, like a thin sheet of stainless steel around a pen in a helix.  About the size of a hacksaw blade but thinner.  The tool would follow the edge like a pencil follows a ruler when drawing straight lines.  That's a long shot though.


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## DCBluesman (Feb 15, 2005)

Milling machines offer a mid-price alternative to CNC and metal lathes.  The Beall Tool Co.'s Lathe Wizard and the Legacy Ornamental Mill are a couple of alternatives to look into.


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## JimGo (Feb 15, 2005)

Wow, those are cool!  WAY outside of my price range, but cool!


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## btboone (Feb 15, 2005)

Very neat products, that's for sure.  It looks like the ornamental tool only does long pitches like 1.5" for the less costly models.  Does that sound right Lou?  I saw where you could get some different gears, so maybe pitches like 3/8" are possible.  I didn't see examples like pens for the lathe wizard.  I assume it can do the same kinds of things?


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## DCBluesman (Feb 15, 2005)

I'm going to see it this weekend, Bruce.  I'll report back.


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## btboone (Feb 15, 2005)

exotic tools. gotta love em.[]


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## woodscavenger (Feb 15, 2005)

From the horses mouth.  Others have done much a much better job than I but since you asked here's what I did.

1. Start with a beautiful burl.
2. Create you basic shape, finalize the end sizes and decide to take one more little shave off
3.  HAve a nasty skew catch.....this created a spiral about 2 turns with the spacing you saw on my top tube.
4.  Mope for a couple of days about how beautiful it could have been
5. Dream about having a CNC machine or metal working lathe with slow speed threading capabilities
6. Remount the blank.
7.  Use a small triangle shape file and follow the basic spiral slowly up the length of the blank with an initial scratching then slowly hand file it to whatever depth floats your boat.
8.  For the bottom I got a little more scientific.  I used a razor knife and held it on the blank and braced it on the turning rest.  I eyeballed an angle....about 20degrees and held the knife in place while turning the blank by hand (reverse direction...wood turning away from me) and as the blank turns, the angle of the razor will scribe a beautiful spiral pattern.
9  Repeat step 7

I am sure there are better ways and I will try them sometime.  For now I call it a good save.  Thanks for the interest.


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## btboone (Feb 15, 2005)

Woodscavenger, how slow can your lathe go?  I assume on step 7 that you did that under power?  Did you really have to chase after the line or was it going a comfortable speed?


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## Tom McMillan (Feb 15, 2005)

My understanding after emailing Legacy was that the small Legacy would only do the 1.5 inch pitch, and to my understanding no others were yet available for it---although there are other models, and I'm not sure of their capability and are a bit spendy.  Another tool I was going to set up to turn spirals was the old Sears Router Crafter,---Sears no longer makes them----but, they are still made in England called the Trend Router Lathe.  I ordered a part for it from Woodchuckers from Canada and they got me one from Craft Supplies of Enbland.  I've since sold it because it would have had to be adapted for pens---I don't know how tight a spiral it woud turn either.  Another tool I had (didn't use it and sold it too)---was the Sorby spiralling tool.  I was told by a couple of dealers that it wouldn't work for pens---but, I emailed Sorby and they told me they thought it would work for some pens.  Not sure if anyone here's used one??  Also, Alice used the Legacy---did she buy one???  Alice, any info???  If all else fails---I've really found it fun to make the spirals by hand and I'm kind of glad I had the opportunity to learn it---even though I do yearn for one of the Legacy or Beall tools.  Another tool Woodcraft used to have was the Mill Lathe made for pens for spiraling and other capabilities for pens---unfortunately it's not available anymore unless you could happen upon a used one.


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## woodscavenger (Feb 15, 2005)

I just got my new jet mini VS but I forgot about that option when I did this spiral.  My old lathe low end was 600rpm.  I didn't even think to power chase it.....hmmmmm.  It was all under old fashioned elbow grease.  It was actually pretty easy.   3-5 strokes, turn about 1/8th turn and repeat all the way up then back down.


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## JimGo (Feb 15, 2005)

Thanks guys!  WoodScavenger, FWIW, it came out GREAT!


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## btboone (Feb 15, 2005)

Hand filing is probably the safest way anyway.

It doesn't look like engineering a machine like Lou referred to would be that tough.  It could be a hand cranked thing that drives a nut along an all-thread rod while pulleys attach the all-thread to the slower rotating main mandrel that the pen rides on.  Depending on the pitch of the all-thread, a pulley reduction of something like 1:8 might be used.  This means 8 cranks of the handle would drive the nut 1/3" while the pen rotates once if 24tpi all-thread is used.  The nut that rides on the all-thread could pull a sled with a Dremel tool back and forth.


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## jwoodwright (Feb 15, 2005)

I know I haven't lost my mind, there was supposed to be a Oramental Mill that mounted on the Jet Mini and did spirals and such with a laminate trimmer.

The info on the Legacy sounds like a stand alone machine, even the smaller one with laminate trimmer...

Dreaming [?]


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## JimGo (Feb 15, 2005)

Bruce, I get the feeling you've done this before...   Need help with the design?


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## DCBluesman (Feb 15, 2005)

I'm thinking more along the line of the (greatly over-priced) Foredom tool, primarily due to the fact that it has a 1/4" chuck.  The 3/16" max of the Dremel is VERY limiting.


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## JimGo (Feb 15, 2005)

How about something like this?  http://www.theokspindoctor.com/framewelcome1.html


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## btboone (Feb 15, 2005)

I'm just doing some napkin sketches.  This thing is easily doable for a Dremel tool.  The Dremel can handle ball type cutters that are larger than the shaft.  You could use a 3/16" ball and only plunge to half depth.  I have it so you can adjust the depth of cut.  The whole thing is made with allthread and maybe a block of plastic or aluminum (maybe even wood) for the nut part.  This deserves a CAD drawing.


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## jwoodwright (Feb 15, 2005)

Nice...  Now a Mini Lathe version...  Thanks for the link...


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## DCBluesman (Feb 15, 2005)

I'm fairly certain you're referring to the Lathe Wizard and gear drive assembly.  Check it out at http://www.bealltool.com/lathewiz.htm 





> _Originally posted by jwoodwright_
> <br />I know I haven't lost my mind, there was supposed to be a Oramental Mill that mounted on the Jet Mini and did spirals and such with a laminate trimmer. Dreaming [?]


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## elody21 (Feb 15, 2005)

Tom, I did end up buying one! I am still waiting for it to come. They do not have them to take home at the wood show. I'll let you know when it comes! 
The legacy 200 only does one pitch there are no opions for this model, You can different bits to change the look. You can do reeds and beading.I have  a lot of ideas of things to try. I also plan on making pillars in white Corian for wedding cake stands. "I design and make wedding and party cakes" It also come with templates for duck calls, candle holders etc.. It will be interesting to see what it can do.
I will be sure and inform everyone how it does when it comes in.
I had the Beall lathe wizard. I did not like it and sent it back. It ran on a Dremmel instead of a laminate trimmer and to get everything to do sprials it is at least $100.00 more that the Legacy 200!

To Be Continued..........

Sorry guys, My order for the Legacy 200 was delayed by a month. In that time I reliezed that I did no need another toy! So I cancelled the order before it was even shipped!


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## jkirkb94 (Feb 19, 2005)

There is an example of turning spirals on pens using a Legacy machine in  Turning Pens and Pencils by Kip Christensen and Rex Burningham.  This book helped me in my earlier turning days.  Kirk[8D]


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## Fred in NC (Feb 19, 2005)

Just my take, ok ?  

In this day and age of CNC such mechanical devices are outdated.  

I think Bruce would agree with me!


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## JimGo (Feb 19, 2005)

but cnc takes away the "hand made" quality of the pens!


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## Fred in NC (Feb 19, 2005)

Right, Jim, it does ...

Let me ask this, what did Bruce use to make his titanium pen?


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## DCBluesman (Feb 19, 2005)

Each generation talks of taking the "hand made" quotient away from the art.  I've talked to one gentleman from Richmond who told me the exact same thing about motor driven lathes as he continued working on his treadle model. (He's over 80 at this point and still turning.)





> _Originally posted by JimGo_
> <br />but cnc takes away the "hand made" quality of the pens!


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## Fred in NC (Feb 19, 2005)

I was just talking about the Legacy, Lathe Wizard, Router Lathe, and other similar <b>rotary milling</b> machines.  The capabilities of these machines are usually limited by a design based on gears and pulleys.  The ratio of the spirals is based on gear changes.  To me the technology used in these machines is obsolete.  Still they are usable machines that serve a purpose.

Electronics and servo <b>or</b> stepper motors (they are not the same thing) could greatly improve the range of spirals and designs that can be made with a rotary mill. At the very least, the ratio of the spirals could be made variable.

I can understand the limitations when a manufacturer is trying to sell a piece of equipment for about $400.  There is no way they can sell controllable motors and electronics in that price range.

However, when you talk about a $5000 machine the situation changes a great deal.  That kind of money can buy a mechanical machine <b>or</b> a woodworking CNC router.  A <b>woodworking CNC rotary mill</b> is feasible for such a price. I will not be surprised if Legacy, for example, introduces such machines in the near future.  

<b>Most</b> of the work we do is better done by hand in a wood lathe, especially talking about one of a kind pieces.  What I can do with a chisel in my Jet Mini in 5 minutes would take a lot longer to program in CNC.  Once programmed, that is exactly what a CNC machine will cut.  There is no allowance for last minute changes (unless you change the program).  

On the other hand, I could drill the holes with an egg beater (hand drill), and use a rasp to shape the barrel.  Handmade?  NO!  look at the metal parts !!!!


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## btboone (Feb 19, 2005)

&gt;In this day and age of CNC such mechanical devices are outdated. 

True enough Fred, but the cost is a huge issue.  As I said, I have a design for a spiral cutting machine like those that could be made for something like $25 to $50 from easy to find parts.  It would be a lot less flexible, but should be able to do some basic spirals.  I still need to draw it up.  I've been a little busy lately. []  Obviously, I don't need one since I have a couple 4th axis machines, but if anyone might be interested, I'd be happy to draw up what I have in mind.  I need to catch back up on rings in the short term though.


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## woodscavenger (Feb 19, 2005)

Bruce, any sketches would be wonderful.  Thanks for even thinking of us lowly people without a 4 axis machine.  Now exactly what is a 4 axis machine.  I think back to my basic geometry and can think the X,Y,Z coordinates.  The 4th one?  Is it that you can finally travel through time and do these things faster? []


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## Fred in NC (Feb 19, 2005)

Basic MILLS have 3 axes.  Standing in front of a mill and looking at it, these are the primary linear axes:

x moves right and left
y moves to and from you
z goes up and down

The Electronics Industry Association (EIA) has defined the following ROTARY axes.  They are just ways to describe motion around the respective axes:

A rotates parallel to the x axis
B "          "            y
C "          "            z

A vertical rotary table at the left of the mill's table, for example, would rotate on the x axis, and would be considered a fourth axis. This is a very common arrangement for cutting gears.   This is also very commonly referred to as a FOURTH AXIS.  

Sorry no pics at this time.


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## btboone (Feb 19, 2005)

Yup.  Fred nailed it.  A controlled rotary axis.  Kinda like a lathe axis under a milling machine, but controlled rotation just like the other axes.


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## Tom McMillan (Feb 19, 2005)

Bruce---I would be very interested in the design you're thinking of for a spiral machine---if, and when you have time to do it.  I don't agree that machines like Legacy and others are outdated at all (especially for penmaking)---when they get a CNC down to $400 or $500 maybe then.  Heck, it would seem like the old Sears router crafter would be outdated (although still made in England by Trend)---but they still sell for much more than they cost new on EBAY.  I'm sure most of us couldn't consider a CNC machine because of the huge cost.  But, remember Bruce, I'm still open to that "apprenticeship"!!


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## JimGo (Feb 19, 2005)

Yes Bruce, PLEASE post anything you have.  I'd be happy to work with you on the design, too.

 - Jim


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## btboone (Feb 19, 2005)

I'll do that Jim.  I've got about 20 rings to get through tomorrow, but I'll try to get on top of them soon.


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## JimGo (Feb 19, 2005)

No rush Bruce.  I'd just love to see what you have in mind.  BTW, your rings are AWESOME!


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## Paul in OKC (Feb 19, 2005)

> _Originally posted by JimGo_
> <br />How about something like this?  http://www.theokspindoctor.com/framewelcome1.html


Hey, I've been to this guys house[]. Don't remember if he had one of these done or not though.
 I'd be willing to help on this project if any extra is needed. I agree that one could be made very reasonable.


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## btboone (Feb 19, 2005)

Paul and Jim,
I should be able to draw up something workable.  I'll need someone with some manufacturing savvy to help sweat details to help make it workable and more manufacturable.  Instead of toothed belts or gears, which are both fairly expensive, it might be possible to use a couple O rings in homemade pulleys to drive the pen shaft.  Stuff like that needs to be proven out before it's ready for the masses.


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## Paul in OKC (Feb 19, 2005)

> _Originally posted by btboone_
> <br />Paul and Jim,
> I should be able to draw up something workable.  I'll need someone with some manufacturing savvy to help sweat details to help make it workable and more manufacturable.  Instead of toothed belts or gears, which are both fairly expensive, it might be possible to use a couple O rings in homemade pulleys to drive the pen shaft.  Stuff like that needs to be proven out before it's ready for the masses.


Making the proto-type is no problem. I had thought about plastic gears, but may be too costly as well. As long as the depth of cut wouldn't pull and cause the belt to slip. Making pulleys is no problem, could make a couple of steps for different pitches if we want. I have access to some larger o-rings at the shop. If they are not long enough, we buy them locally so it would be easy to check size.


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## btboone (Feb 19, 2005)

Paul, the issue is the 8:1 ratio.  Gears would be great, but they are expensive to get from most places.  A source for cheap ones might be in toys or other molded plastic parts.  For O rings, there would have to be several of them in tandem.  The good news is that the hard to turn shaft that drives the nut is directly rotated with a handle.  The geared down one (thus mechanically advantaged one) will be the pen rotating.  The distance of the nut traversing shaft needs to be somewhat close to the pen spindle so the Dremel could be as close as possible to the pen.  If the larger gear or pulley is 2" diameter, this only leaves 1/4" diameter for the smaller one, so it will have to be a good grip and multiple O rings to be sure.  A higher helix will need an ever higher drive ratio.


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## Fred in NC (Feb 19, 2005)

What pitch leadscrew are we talking about?

Acme rod comes in pitches that are more suitable for this purpose, like 3/8-8.  Then the pulley ratio can be smaller.
Cost is under $3 per foot at McMaster. A nut costs a couple dollars.


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## btboone (Feb 20, 2005)

Wow Fred, That helps.  I was assuming 1/2-13 or so.  The smaller pulley can be larger with that.


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## Fred in NC (Feb 20, 2005)

Sewing machine belts don't stretch as much as o-rings, which are by nature flexible.  I have seen them for about a dollar.  They will probably need an idler to take slack when changing ratios.

ADDED:  Eureka vacuum cleaner belts are the same as used in older sewing machines. Cheap!


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## btboone (Feb 20, 2005)

There are also those tiny toothed belts that would also work great.  I think the pulleys for those are relatively expensive though.  I haven't sourced any so I could be wrong on that.


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## JimGo (Feb 20, 2005)

Bruce,
Do you think we could make something with adjustable jaws, like a self-centering 4-jaw chuck, so that the operator could adjust the size of the drive gear?  That would allow the operator to almost "infinitely" adjust the helix.


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## Fred in NC (Feb 20, 2005)

Bruce, I have priced them.  Not cheap!

Also, poly-v (serpentine) belts provide a lot of traction.  I buy them for Jet Mini and they are inexpensive if you get them from the source.  The pulleys are a different story, have not found them !


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## btboone (Feb 20, 2005)

Jim, anything is possible.  If the constraints are to be making a machine that's in the range of, say $25, then we might be pushing.  I was originally considering a machine that would create a single spiral with a fixed pitch.  It could be changed over by changing pulleys, but adding on any capabilities will add complexity and cost as well.


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## Fred in NC (Feb 20, 2005)

Ah, Bruce !!!  If the design uses a FLAT belt, like the vacuums, then there is no problem !!!!

Anybody with a lathe can turn a pulley for a FLAT belt !!!!
Then we can have whatever pitch we want.  Even hardwood will work for a pulley.  It might need an idler to take the slack, that's all.


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## btboone (Feb 20, 2005)

I agree Fred.  They would just need to make different pulleys though.  I don't see a way to be able to change pitch easily without changing out those pulleys that doesn't add a lot of complexity like variable speed drives and such.


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## btboone (Feb 20, 2005)

The idler also has the advantage of being able to be used to creat multiple start helices.  One would be turned, then the spindle would be locked and the idler loosened.  The nut driving screw would be advanced without the pen turning, then the idler would be reengaged.


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## Tom McMillan (Feb 20, 2005)

Really sorry guys---but I've just got to say I'm salivating over all of this--all of your expertise is almost too much---WOW--- " SPIRAL MACHINEP" can't wait to see what you all come up with!!!!!!!


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## Fred in NC (Feb 20, 2005)

Well, first of all, thank you Tom for your kind comments! Paul and Bruce are experts in the machining field. I am not an expert at anything, but I like to contribute whatever I can to a project like this.  I call it brainstorming.

There is a lot more to it than experience.  The word ex-perience implies knowledge from outside sources and long time practice.  Those who shine in their fields, like Bruce, Paul, and many others in this group, have an additional quality that does not come from experience.  It is the ability to create new things.  Some are beautiful, some are practical, and all are new.  My hat tips to such people!  Thank you for your contributions to IAP, the group, and the art of penturning.


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## Paul in OKC (Feb 20, 2005)

There is a lot being said here about ratios and what not. I have a bad enough time trying not to turn my projects into rocket science[]
But to keep the price low, it will have to be a single pitch, I think. I also was thinking of acme rod like 1/2-10. 4:1 would be like 2 1/2 threads per inch. An idler would help give more ratios. I'm not sure what would be the most 'popular'. It would take some gearing down to make less than one spiral per barrel. I will check my sources for plastic gears and or timing type stuff.


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## Scottydont (Feb 20, 2005)

I am interested in what the creative minds come up with here. I happen to have the new Legacy 200 milling machine. It is designed specifically to do pen type spindles. I bought it do spirals and I like using it to turn end grain cut pens that tend to have blow outs and do the final shaping on the Jet Mini. I have not used it too much yet. I am in the process of building a cabinet to have the Jet mini on one side and the Legacy on the other. I would be interested if it would be feasable to have different diameter gears cut on a CNC machine.

http://www.legacywoodworking.com/products.cfm?product=36


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## DCBluesman (Feb 20, 2005)

I tried that machine for about an hour or so today and was not totally pleased with the results.  I'll be pleased to see what your experience is, Scott.


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## btboone (Feb 20, 2005)

Scott, gears are usually done on a hobbing machine, something that cuts gear teeth in a stack of gears that ends up looking like a corn cob.  The more normal CNC machines won't do a good job of them since they would have to rely on a thin cutter cutting through thick stock.  There would be breakage and chatter issues.

I'm unbelievably slammed with ring orders for some reason, something like 25 rings (around $8K worth,) so I might have to ask Fred, Jim, or Paul to draw up the initial stuff unless it can wait another day or two.


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## Fred in NC (Feb 20, 2005)

Lou, I appreciate your opinion because I have been considering the Legacy too.  Would you mind explaining what you did not like about it?  Thanks !

Scott, cutting gears is possible of course.  But one reason I was proposing flat vacuum belts and pulleys for our design is that we can easily make sets of pulleys with different ratios with a wood lathe.  The pulleys would be just a wood or plastic disk with a recessed flat in the middle. Piece of cake!


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## JimGo (Feb 20, 2005)

Fred,
I agree with you.  I also think that this will pretty much be a necessity.  What I was thinking of, and my understanding of Bruce's original design, was something that used a belt of some sort to attach to the drive spindle of the lathe.  Since each lathe is going to probably have different gearing, or for the variable speed ones, different drive spindle size, I thought we'd NEED to be able to make our own gears.  Bruce, I might be able to rough something out tomorrow, although I don't have CAD software (so it may be a little rough!).

 - Jim


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## DCBluesman (Feb 20, 2005)

> _Originally posted by Fred in NC_
> <br />Lou, I appreciate your opinion because I have been considering the Legacy too.  Would you mind explaining what you did not like about it?  Thanks !


Ok, but remember that this is just a one-hour trial (actually, I was demo'ing since Legacy's man was busy with the 1200).

I first visited yesterday and was disappointed by the fact that the machine could not be demo'd...No blanks, if you can imagine.  The machine's mandrel is a 7MM and there are no options. I went home, grabbed some different species of blanks and cut/drilled/tubed them for today. Upon my return I was shown how to set up and run the machine.  It is simple to use.

The first thing that struck me is that the design is built around the Porter Cable Model 7310 Laminate Trimmer.  That means you have a 5.6 amps and a single-speed (30,000 RPM).  The Laminate trimmer lists for $190 but can be found online for around $115.  That's quite an expensive addition to the $359 for the Legacy Model 200.

Another drawback (for me) is that it turns left hand spirals, exclusively.  That's not bad (necessarily) for pens, but is a real drawback in making salt/pepper shakers or candlesticks which should be spiraled to compliment each other.

The index wheel is 12-position (30-degree) with no options for change out.  The spiral pitch is 1-1/2 inches, non-adjustable.

In turning pen blanks, I tried maple, afzelia, black and white ebony and rosewood.  Blanks were between 5/8 and 3/4. I was turning them down to .030 inches, adjusted with a feeler gauge.  I was turning a 1/4" spaced repeating spiral, requiring 6 passes to cut the spirals.  Six passes is not undesirable, since they go quickly, but I soon found out that the combination of motor amps, RPM's and depth of cut made it impractical to cut each spiral in one pass.  Instead, each spiral requires two passes (maple) to 4 passes (black and white ebony) to complete the spirals (that's 24 total passes for one set of blanks). FYI, the B&W ebony  and the rosewood were 5/8".

Of a dozen blanks turned, only 4 turned without serious chipping or full blow-outs.  This may be due to have an old cutter.  I have no way of knowing.  Of these blanks, all will have to be buffed significantly since the surface is too rough (for my standards) to begin finishing.

Overall, I think this machine grades out at a B-.  In considering the price, Probably no better than a C.

I hope I'm wrong about this machine.  When others who have purchased the machine get use to it, they may find that my one-hour test was not indicative of it's abilities.  I'm open to being wrong on this one.


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## btboone (Feb 20, 2005)

Jim, what I had in mind didn't use the lathe at all.  It would be a free standing 3 sided box maybe around 8" long x 4" x 4" deep made from wood or plastic with maybe 3/4" walls.  The pen would be mounted on a 1/4" allthread rod and secured with nuts.  The threaded rod should fit within a 7mm brass bushing of a pen.  The large pulley (just a turned cylinder around 2" diameter and maybe 3/4" thick) would ride on that shaft and some nuts would lock it in place.  Above and to the left of the pen shaft would be the nut driving shaft.  It can be the 3/8-8tpi acme thread that Fred was referring to.  Another pulley, this one much smaller, like 1/2" diameter is locked onto this shaft.  This shaft is the one that extends through the wall and has a handle on it.  The nut is attached to a wood or plastic carriage that the Dremel is mounted to.  The carriage is only supported by the nut, so is free to rotate about the axis of the shaft.  Rotation is stopped at the centerline of the pen shaft by another wall of wood or plastic that the carriage can scoot along.  The Dremel cutter would be engaged into the pen when in this position.  There can be a screw that acts as a depth adjustment on the bottom of the carriage.

In a nutshell, that's what I had in mind.


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## Fred in NC (Feb 20, 2005)

Thank you, Lou.  Appreciate your candid comments.  

A laminate trimmer might not be the best tool for routing pens.  The wood is rather thin for that.  Also, I dislike the idea that it is not very adjustable, has a lot of limitations. The $500 investment for that seems to be very high for me.

Back to the drawing board!!


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## JimGo (Feb 20, 2005)

Thanks for the clarification Bruce!

Lou, thanks for the review, and for taking the time to do the great finishing write-up!


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## Fred in NC (Feb 20, 2005)

Bruce, your idea is very simple !!!  And simple is EXCELLENT in my book ! Very few parts makes it simple to build and adjust.  

Now, if we could get hold of an ACME tap to match the rods, we could make some nuts from delrin or similar plastic.  My idea is to make a long nut, so it engages 12-16 threads.  Less wear and less backlash.  I did not see a tap for this size, but somebody must have it.  The ACME taps are expensive !!  Probably $50 or so for this one. Whoever buys the tap should sell the nuts to cover his cost and labor.  I am not sure about making them with the CNC because of the square valleys in ACME threads.

Let's keep brainstorming, soon we will have a design to try out.


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## btboone (Feb 20, 2005)

Fred, I was thinking to buy an acme nut and press fit it into an undersized hole in the plastic.  It can then be setscrewed in place just to be sure.  The other end of the hole can simply be a 3/8" hole to ride on the outside of the threads.


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## DCBluesman (Feb 20, 2005)

A picture's worth (more than) a thousand words.  Here's some samples. The burns are avoidable--sometimes--but it may mean a few more passes with shallower cuts.


<br />





> _Originally posted by DCBluesman_
> <br />Of these blanks, all will have to be buffed significantly since the surface is too rough (for my standards) to begin finishing.


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## Fred in NC (Feb 20, 2005)

Bruce, that might work ....

The reason for the plastic nut is this: a slit can be cut along the axis, and used to compress the nut to control the slop. Of course, some backlash is not a problem when you are turning the shaft in one direction during the cut.


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## JimGo (Feb 20, 2005)

Lou, thanks for the pics!  Those are surprisingly rough!


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## woodscavenger (Feb 20, 2005)

You guys lost me on page two with the technical mumbo jumbo.  Keep at it though.  I would love to see a sketch.  My brain can't wrap around what you are trying to build.  For now I will stick with my hand cut method.


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## JimGo (Feb 20, 2005)

Shane,
your pens come out great, so I don't blame you for wanting to stick to the hand cut method.  This is a way for those of us without our steady hands and skilled artisanship to cheat! 

Bruce or Fred, do you guys know of a decent open source or free technical drawing program?  As an EE, I don't usually need that kind of software!


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## Fred in NC (Feb 20, 2005)

Sheesh, Lou, not what I would expect from a $500 setup.  Maybe the router bit is part of the problem.


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## Tom McMillan (Feb 20, 2005)

Wow, Lou---Thanks for sharing that---Guess, for now, I'm best to continue with my hand spirals too---but, I would think there would be a way to get a smoother cut with that Legacy.  Maybe Scott will do some work with his, and report on the results----Others here have Legacy's and made spirals---seems I've seen some????  Successes---failures???


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## btboone (Feb 21, 2005)

Jim, there's an excellent one called Rhino (www.rhino3d.com) which has some nice software that can do 2D or 3D.  (It could actually draw the shapes that Lou posted.) The full working version can be downloaded for free for you to try.  It saves only around 15 times though.  The software is relatively cheap for as powerful as it is, and students get a huge break on price.  I have seen a couple others that are free downloads, but I can't think of their names at the time.


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## DCBluesman (Feb 21, 2005)

I let JR Beall's buff along with a load of tripoli and white diamond work for a while on these.  



<br />
I doubt these are going to see even a 24k slimline, though.  The Model 900 can produce some exceptional pens, but at $1,300 it darned sure should!  This machine's technology is much different. 

Also, for $400-500, how many spiral pens would I have to sell?

Truly, though, I hope Alice and Scott show that this was an aberration.  [8D]





> _Originally posted by Tom McMillan_
> <br />Wow, Lou---Thanks for sharing that---Guess, for now, I'm best to continue with my hand spirals too---but, I would think there would be a way to get a smoother cut with that Legacy.  Maybe Scott will do some work with his, and report on the results----Others here have Legacy's and made spirals---seems I've seen some????  Successes---failures???


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## ctEaglesc (Feb 21, 2005)

I have been reading this since 4:00 this morning and was wondering something.
Instead of buying taps and dies and gear ratios and all that stuff.
Here's where my uneducated thinking comes in,
Would it not be easier to modify a large C clamp to hold a Dremel tool?
The treads are already cut.
As you "screw" the C clamp it would advance the Dremel with whatever size bit you would need.
It would seem you could make a set of pulleys and a windlass arrangement.
Car jacks,house jacks, C,turnbuckles clamps all use Acme threads do they not?
For less than $20.00 you have the male and female parts and you are not doing all the tooling.
If I'm missing something as to why this would not be easier let me know.
(Great now I have something to think about while I'm getting ready for a "Sportsman Show")


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## Gregory Huey (Feb 21, 2005)

Lou
Thanks for the pics, I am now going to think about this machine a little longer.


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## Paul in OKC (Feb 21, 2005)

> _Originally posted by Fred in NC_
> <br />Bruce, your idea is very simple !!!  And simple is EXCELLENT in my book ! Very few parts makes it simple to build and adjust.
> 
> Now, if we could get hold of an ACME tap to match the rods, we could make some nuts from delrin or similar plastic.  My idea is to make a long nut, so it engages 12-16 threads.  Less wear and less backlash.  I did not see a tap for this size, but somebody must have it.  The ACME taps are expensive !!  Probably $50 or so for this one. Whoever buys the tap should sell the nuts to cover his cost and labor.  I am not sure about making them with the CNC because of the square valleys in ACME threads.
> ...


I was thinking along this line as well, Fred. The only acme taps I have seen start at 1/2-10, and they are around $50.  Bruce, your idea is definately a good way to keep it simple as to the carriage. I'm not sure about stability though. I thought about the carriage being on two rods with the screw in the middle. This of course takes more machine work which makes the cost a little more. I'll see if I can get some time to draw up some thing as well. Looking forward to this 'collaberation' project[]


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## Fred in NC (Feb 21, 2005)

Paul:  I think the  reason for Bruce's design is that it will simplify raising the router out of the work.  It will not actually rise, but swing out of the way.  At any rate it looks like we need to be able to control the depth of the cut.

As for the plastic nut and tap, I have found that plastic give a little bit when tapped, and the resulting threaded hole is more accurate, ie.  tighter.  Enco has taps like you said for $50.


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## J. Fred Muggs (Feb 21, 2005)

<br />


Alright, I apologize for the picture size.

What if I told you this was done with a hand held, non-motorized, almost like a chisel, powered by the rotation of the piece in the lathe, sells retail for $150 list, comes with the ability to do three sizes of cut, variable pitch, left or right hand, CD included, etc. etc.????

Would you be interested???

It's known as the Robert Sorby spiralling and texturing tool. 

It works by simply engaging a gear-like cutter with axis of rotation of the cutter somewhat perpedicular (but at a slight angle) to the axis of rotation of the workpiece. This angle causes the cutter to rotate. by then sliding the cutter along the length of the workpiece, you create a spiral cut in the workpiece. by angling the cutter to the left you create a spiral that runs right to left. Angle it the other way, it runs left to right. The angle at which you present the cutter to the workpiece determines the pitch of the spiral. To create a checkering effect like the pen above, you cut a spiral in one direction, then a second spiral in the other direction.

The checkering above was done using the smallest pitch of the three supplied cutters. Also the piece was sanded heavily after cutting because I wanted a checkered look as opposed to just a spiral. 

Due to time limitations I have not had much opportunity to play with this tool. It does take some time to master. Additionally&lt; I didn't get the free CD when I bought mine. But did get one just about a month ago. Honestly, so far, this is the only pen I consider salable. But then, I've only tried about four, so far. I bought the tool more for faceplate useage. You can see a sample of that in a pocket watch case in pink ivory in my album. The best efforts of that were sold before I could get pictures.

Take a look at http://www.robert-sorby.co.uk/ under woodturning tools/spiralling/texturing system.

My experience so far: It does not work well in softer woods that are prone to tearout. The pen above is tulip wood. It does require some practice to master (I do not claim to have come close to mastering it yet).

Go to this site http://www.carolinamountainwoodturners.org/ click on Michael Mocho/ August 2005 under demonstrations at the top left and you can see Mocho using the tool in both spindle and faceplate applications. It was this demo that conviced me I had to have one.

The tool itself is little more than a gear with a ball bearing held on the end of a turning tool. I'm confident Bruce and probably many more of you could make your own for twenty bucks or so.

There are, indeed, alo of ways to make a spiral. This method, you could legitimately says is still "handmade" as much so as using any other tool in conjunction with a motorized lathe. It's less expensive to buy retail than many of the other spiralling systems. And, from what I see in this thread sofar, It really oughta get all your thinking caps really buzzing.


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## darbytee (Feb 21, 2005)

Fred, I've got one of those Sorby spiralling tools that I haven't even used yet. It was given to me by the guys at my local Woodcraft in compensation for doing a demo and helping out with their Freedom Pen Turnathon. I want to go play with it now!!


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## btboone (Feb 21, 2005)

Fred, I've never tried them on wood, but a knurling tool for a metal lathe does just that pattern.  They are usually quite a bit cheaper, like in the range of $20 to $50.


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## btboone (Feb 21, 2005)

Fred, I've never tried them on wood, but a knurling tool for a metal lathe does just that pattern.  They are usually quite a bit cheaper, like in the range of $20 to $50.


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## woodscavenger (Feb 21, 2005)

That's a cool pattern.  How controllable or repeatable is it?


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## Paul in OKC (Feb 22, 2005)

I made one cutter like this once. Didn't quite have the edge right and haven't played with it since, but it can be done.


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## Tom McMillan (Feb 22, 2005)

Nice work on that one Fred!!  Kinda wish I hadn't sold my Sorby spiraling tool---looks like that worked pretty well for you!!  I just didn't use it at the time.


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## Paul in OKC (Feb 22, 2005)

Here's a quick starting sketch for ideas on the spiral cutter.

<b>Download Attachment:</b> 


 spiralctr Model (1).pdf<br />7.79&nbsp;KB


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## Paul in OKC (Feb 22, 2005)

Next question, how do I post a copy of this here, or can I?



> _Originally posted by Paul in OKC_
> <br />Here's a quick starting sketch for ideas on the spiral cutter.
> 
> <b>Download Attachment:</b>
> ...


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## Paul in OKC (Feb 22, 2005)

One more try







<br />


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## Paul in OKC (Feb 22, 2005)

> _Originally posted by Paul in OKC_
> <br />One more try
> 
> OK OK I give up. I got a pic in my photo album.


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## Fred in NC (Feb 22, 2005)

I know it is a simplified drawing. Looks fine to me.


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## J. Fred Muggs (Feb 22, 2005)

Bruce:
I'm not a machinist, but, it's my unserstanding that a knurling tool does it's thing by displacing metal rather than removing it.  The Sorby tool removes the wood. 

Since you are the machinist, go by Highland Hardware or your local Woodcraft on Holcombe Bridge Road and check the Sorby tool out.  I have every confidence that with your obvious aptitude and a CNC machine, you could make these things and improve on the design, functionality and ease of use.  Then we can all buy a Boone Spiralling tool.  Additionally, I believe you could make the concept work in conjunction with the CNC and do wonders in both wood and metal.

I know you need more things to fill all that spare time you have.  Glad I can be of assistance.[]


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## btboone (Feb 22, 2005)

Yes, I certainly appreciate that Fred! []  I've been working for the last few days straight and my number of rings has only gotten larger!  Calgon, take me away!

Paul, your machine looks somewhat similar to what I had in mind.  I found that on my Dremel, the plastic tip comes off, exposing some threads, so the whole Dremel tool can screw down to the nut block and can be held much closer in to the pen axis, so it should be stiffer that way.


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## DCBluesman (Feb 22, 2005)

Paul--the software for loading pics into posts only allows .jpg files up to 90kb and the filename must not include special characters, like the parentheses.


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## J. Fred Muggs (Feb 22, 2005)

Unless I've severely misjudged you, you're gonna be kicked back in that tub of Calgon (or more probably sweatin' in the shop) and those little spiral making gears are gonna be turning in your noggin figurin' ways to do funky things on pen barrels with all of these ideas in this thread.[][][][]


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## Paul in OKC (Feb 22, 2005)

> _Originally posted by btboone_
> <br />Yes, I certainly appreciate that Fred! []  I've been working for the last few days straight and my number of rings has only gotten larger!  Calgon, take me away!
> 
> Paul, your machine looks somewhat similar to what I had in mind.  I found that on my Dremel, the plastic tip comes off, exposing some threads, so the whole Dremel tool can screw down to the nut block and can be held much closer in to the pen axis, so it should be stiffer that way.


I kinda thought this was close to what you had thought about. The threads on the end of the dremel are odd sized. I made a tap for one to try to screw it into some aluminum on an old patern for a pantograph from a 50's Popular Mechanics project. May have to dig it out and check it. Have to figure out a depth adjustment of some sort.


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## JimGo (Feb 24, 2005)

Came across this link from YoYoSpin's Pikes Peak Woodturners Club page (http://www.yoyospin.com/ppw/how.html), and thought it was interesting.  I wonder if something like this might not work for our purposes.  Just need to get different thread ratios.  Obviously, it will give you the 8TPI look, if you like it.  Maybe having the handle also pull the cutter in closer as the blank is pushed forward would accomplish this?

http://www.jeanmichel.org/thread.htm


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## dozuki (Mar 28, 2005)

How do you get the two tone effect.  I think the best way to cut it would be by hand but how do you get one color of wood under the other


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## Tom McMillan (Mar 28, 2005)

Hi Paul---Not sure if you're referring to my 2 layer spiral pens.  If so, I take the first layer of pen blanks and turn them evenly a little over the size of the bushings.  Then I drill the 2nd layer to fit over the first blanks and glue them on.  Then I do my spiral layout and cut by hand with a rasp.


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