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Evan
10-15-2010, 09:51 AM
On seeing the Gearotic program introduced by John S. I decided to figure out how the process was implemented. A little research shows that it isn't a new idea although the implementation by Art Fenerty in Gearotic is new. The earliest example I could find was a machine patented about 40 years ago that performed the same process via a completely mechanical system instead of a CNC machine.

I determined the method by which facet cut gears are made by investigating the way that an involute is approximated in most CAD programs. The end result in the several programs I checked is a collection of line segments instead of an arc or spline curve primitive. This lends itself to easy description mathematically which is why it is done that way.

The investigation resulted in this initial description of the angles and offsets required to produce a 14 tooth 9DP 20PA gear with an OD of 2 inches.

http://ixian.ca/pics8/fgearmath.gif

Here is the setup I used to make such a gear. The G-code is hand written using a template I created that will allow the easy plug in of variables for any gear. At the moment I am contemplating making a simple stand alone program for the creation of spur gears only. It will be a while before I get to that because I am expecting the new 10" mirror for my next telescope to arrive shortly. The material is black acetal with a 1/8 solid carbide cutter at 5000 rpm.

http://ixian.ca/pics8/fgear1.jpg

Note that the gear was selected to emphasize the facets created. Gears with more teeth will have much less or even invisible faceting.

http://ixian.ca/pics8/fgear2.jpg

The run time of the process was about 30 minutes. The G-code is far from being optimised and the time can be reduced very considerably. The machine is also capable of cutting an acetal gear like this about twice as fast but that makes it hard to see what is happening.

Here is a video of the process. Sorry about the shakycam but it didn't lend itself to using a tripod while making a gear in real time.

http://www.youtube.com/v/ORYjRiqfLCk?fs=1&hl=en_US

Next post is to show some simple low angle herringbone gears that I made by this method.

Evan
10-15-2010, 09:57 AM
Herringbone gears:

It turns out that these were easier to make than I thought. Even with this low helix angle the teeth should much stronger than a straight cut gear.They roll together nicely by hand. I havn't yet jigged them up on power to find out how they sound.

http://ixian.ca/pics8/fgear5.jpg

http://ixian.ca/pics8/fgear6.jpg

http://ixian.ca/pics8/fgear7.jpg

jkilroy
10-15-2010, 10:08 AM
Nice work. Most of the people I know that produce straight spur gears cut them on a water jet, how accurate a tooth profile do you think can be produced that way? Not that it really matters, I am sure the gears produced by the methods mentioned here would be fine in any practical application.

Alistair Hosie
10-15-2010, 10:10 AM
Well done Evan. I enjoyed watching this process. your set up is very well thought out, did you make the milll yourself ? Alistair

Evan
10-15-2010, 10:21 AM
The accuracy of the gears is limited only by the accuracy of the machine since any number of facets may be used to approximate the curve. In this instance I used ten facets which mathematically results in no deviation greater than .0007" on this particular curve. As the curve grows less acute the accuracy with ten facets grows better. The total run time to make a gear will not increase in direct proportion to the number of teeth. As the number of teeth increases the number of facets required to approximate the tooth decreases.

Yes, Alistair, I designed and built the mill.

lazlo
10-15-2010, 10:24 AM
Nice job Evan! I like the term "Facet-cut Gears."

drmico60
10-15-2010, 10:45 AM
On seeing the Gearotic program introduced by John S. I decided to figure out how the process was implemented. A little research shows that it isn't a new idea although the implementation by Art Fenerty in Gearotic is new. The earliest example I could find was a machine patented about 40 years ago that performed the same process via a completely mechanical system instead of a CNC machine.

I determined the method by which facet cut gears are made by investigating the way that an involute is approximated in most CAD programs. The end result in the several programs I checked is a collection of line segments instead of an arc or spline curve primitive. This lends itself to easy description mathematically which is why it is done that way.

The investigation resulted in this initial description of the angles and offsets required to produce a 14 tooth 9DP 20PA gear with an OD of 2 inches.

http://ixian.ca/pics8/fgearmath.gif

Here is the setup I used to make such a gear. The G-code is hand written using a template I created that will allow the easy plug in of variables for any gear. At the moment I am contemplating making a simple stand alone program for the creation of spur gears only. It will be a while before I get to that because I am expecting the new 10" mirror for my next telescope to arrive shortly. The material is black acetal with a 1/8 solid carbide cutter at 5000 rpm.

http://ixian.ca/pics8/fgear1.jpg

Note that the gear was selected to emphasize the facets created. Gears with more teeth will have much less or even invisible faceting.

http://ixian.ca/pics8/fgear2.jpg

The run time of the process was about 30 minutes. The G-code is far from being optimised and the time can be reduced very considerably. The machine is also capable of cutting an acetal gear like this about twice as fast but that makes it hard to see what is happening.

Here is a video of the process. Sorry about the shakycam but it didn't lend itself to using a tripod while making a gear in real time.

http://www.youtube.com/v/ORYjRiqfLCk?fs=1&hl=en_US

Next post is to show some simple low angle herringbone gears that I made by this method.

Brilliant piece of work!
Mike

Black_Moons
10-15-2010, 10:48 AM
drmico60: lol, Next time just hit reply insted of quote.. Or at least, remove the several pages of images from the reply.

Peter.
10-15-2010, 11:35 AM
Nice work Evan. It's amazing how accessible easy gearcutting has just become to the home cnc machinist in a very short time.

dp
10-15-2010, 11:47 AM
Can anyone explain how any of this (Evan's method and the Gearotic method) is different that what JS was doing with this demonstration?

http://bbs.homeshopmachinist.net/showthread.php?t=24252&highlight=helical+gear

The Gearotic stuff is pretty interesting in that it simplifies a lot of the work, but I liked the D-cutter idea as it allows making gears that have less than 1/8" tooth separation (limitation of the endmill diameter).

I don't imagine there's any reason Evan's calculations or the Gearotic software can't work with tapered D-cutters. This is the standard base circle method used by shapers for cutting an involute with a rack form cutter except using multi-axis CNC.

lazlo
10-15-2010, 11:52 AM
Can anyone explain how any of this (Evan's method and the Gearotic method) is different that what JS was doing with this demonstration?

http://bbs.homeshopmachinist.net/showthread.php?t=24252&

It's all the same process -- you're CNC milling a gear from the solid. If you don't want to generate the G-Code directly, the Gearotic is doing, and Evan is doing by hand, you can just download a DXF file and do the same thing on any CNC mill. Evan has done that before too (milled a DXF gear model directly).

Evan, you sure turn your calculations into a Perl script that generates G-Code. That would be very popular :)

leesr
10-15-2010, 12:28 PM
Evan

Impressive, nice work

Leesr:)

Evan
10-15-2010, 12:39 PM
Evan, you sure turn your calculations into a Perl script that generates G-Code. That would be very popular

I intend to do exactly that. However, I am easily distracted. Enormous optically perfect shiny objects tend to do that. The mirror I ordered is accurate to 1/20 wave! :D

Black Forest
10-15-2010, 12:49 PM
Enormous optically perfect shiny objects tend to do that. The mirror I ordered is accurate to 1/20 wave


Evan, don't drop it!

dp
10-15-2010, 01:43 PM
I intend to do exactly that. However, I am easily distracted. Enormous optically perfect shiny objects tend to do that. The mirror I ordered is accurate to 1/20 wave! :D

Very cool - did you get a conical mirror? I've been thinking about that option.

TGTool
10-15-2010, 01:55 PM
It's all the same process -- you're CNC milling a gear from the solid. If you don't want to generate the G-Code directly, the Gearotic is doing, and Evan is doing by hand, you can just download a DXF file and do the same thing on any CNC mill. Evan has done that before too (milled a DXF gear model directly).

Evan, you sure turn your calculations into a Perl script that generates G-Code. That would be very popular :)

I wouldn't have called it the same process, particularly in the discussion of various ways to make gears. It does use the 4th axis under NC control, but John's demonstration required a cutter with the tooth profile on it which would cut a limited number gears in a range just as the regular involute cutter sets do. The Gearotic approach uses a straight cutter without a gear profile.

+2 on the script

Evan
10-15-2010, 01:56 PM
I am going to have to work custom gears into this self hijack. :D

Conical mirror? Do you mean parabolic?


I am thinking of focusing the telescope by changing the optical tube assembly (OTA) length instead of a conventional focuser. That will use several screws that are geared together to produce precisely coordinated extension and retraction of the 2 piece OTA via an electric motor for remote focusing. It will also have a "transport" position where it collapses the OTA to near half it's length to make it easy to stow in the vehicle.

dp
10-15-2010, 02:02 PM
I am going to have to work custom gears into this self hijack. :D

Conical mirror? Do you mean parabolic?

No - the reverse side is conical with a central mounting hole.

http://www.rfroyce.com/conical/

dp
10-15-2010, 02:06 PM
I wouldn't have called it the same process, particularly in the discussion of various ways to make gears. It does use the 4th axis under NC control, but John's demonstration required a cutter with the tooth profile on it which would cut a limited number gears in a range just as the regular involute cutter sets do. The Gearotic approach uses a straight cutter without a gear profile.

+2 on the script

John's approach didn't require a form tool - it did simplifiy it. A rack form cutter and the methods discussed here for controlling the cutter path will achieve the same thing.

camdigger
10-15-2010, 02:19 PM
Manual facet cutting of spur gears has been around for decades. Circular cutters of rack profile used in mill drills and vertical mills, even milling attachments. Often mistakenly described as "hobbing" - see youtube vids on "hobbing" with sherline machines. I think Lautard describes it in one of the bedside readers as a dodge to replace a stripped lathe change gear (don't recall which one of the three).

The most recent example is in our host magazine in Michael Ward's serial article on building the cut knurler - a well illustrated step by step article that details not only cutting the gears, but making the cutter as well..

What makes this different is the resolution and the use of a straight sided endmill.

I'm curious to hear how long Evan spent mimicking the what the Gearotics software does. The Gearotics software is a $75 plugin. How many hours at what hourly rate are you willing to assign the reverse engineering of an existing product?

Evan
10-15-2010, 02:37 PM
edited by self

kf2qd
10-15-2010, 02:40 PM
Nice work. Most of the people I know that produce straight spur gears cut them on a water jet, how accurate a tooth profile do you think can be produced that way? Not that it really matters, I am sure the gears produced by the methods mentioned here would be fine in any practical application.


Seeing as how a waterjet has a .015" or smaller cutter radius it is able to do some pretty fine work. Quality of cut tends to improve at slower speeds and the water jet can cut an amazing veriety of materials. (metals, glass, stone, plastic, concrete, wood, etc) so you culd make gears from just about anything.

camdigger
10-15-2010, 02:43 PM
Illustration of principle complete with documentation of the evolution. Development of code should be trivial for someone with 47 years of programming experience. Call it what ever you want reverse engineering, copycat, "me too, me too!":rolleyes:

Evan
10-15-2010, 02:44 PM
Waterjet is a bit out of reach for the average HSM'er. However, I do have some .015" carbide endmills and will be trying them out to see just how well my mill does on small gears.

Evan
10-15-2010, 02:48 PM
edited by self

camdigger
10-15-2010, 02:50 PM
Illustration of principle complete with documentation of the evolution. Development of code should be trivial for someone with 47 years of programming experience. Call it what ever you want reverse engineering, copycat, "me too, me too!":rolleyes:


And unlimited time to devote to the project due to forced early retirement/confinement for medical reasons...

Jealous? hardly. Ground breaking? hardly...:rolleyes:

Evan
10-15-2010, 02:56 PM
edited by self

camdigger
10-15-2010, 02:59 PM
Just a reality check before you do yourself an injury patting yourself on the back...

You're welcome.....:D :D :D

flathead4
10-15-2010, 03:01 PM
I'm curious to hear how long Evan spent mimicking the what the Gearotics software does. The Gearotics software is a $75 plugin. How many hours at what hourly rate are you willing to assign the reverse engineering of an existing product?


Isn't this in part what HSM is about? Like most of us haven't spent time and effort building something that could be bought for half the cost. But what fun is that? And if you can make it better than the original - even more fun.

I think these discussions are great. Even the bickering is entertaining.

Tom

Alistair Hosie
10-15-2010, 03:02 PM
Evan your workmanship is excellent, and severely put's mine to shame.Still ,I am not an engineer and the way I am going never will be:D.
I do have the basics and then some which suits me for my needs to a T.Thanks again for showing I could watch things like this all day.Alistair

Toolguy
10-15-2010, 03:10 PM
Evan - thanks for sharing with those of us who don't have the time to play around with everything we are curious about. I'm a pretty seasoned metalworker, but one lifetime is way too short to try everything first hand.
I for one enjoy your posts because I get to learn new things and think about old things in new ways. Best Regards.

beanbag
10-15-2010, 03:13 PM
Not counting the square profile at the root, why not cut the profile in one pass with the gear mounted horizontally?

Evan
10-15-2010, 03:14 PM
edited by self

Evan
10-15-2010, 03:21 PM
Not counting the square profile at the root, why not cut the profile in one pass with the gear mounted horizontally?


I have done that as well. It works well but it isn't as accurate because of flex in the cutter and gear width is limited to the length of the cutter flutes. And of course, it can't do herringbones or helices.

rotate
10-15-2010, 03:23 PM
Just a reality check before you do yourself an injury patting yourself on the back...


Completely uncalled-for. Yes, nothing I've seen here is rocket science, but by the standards of many of us here and our humble means, what Evan often presents to us is "rocket science" and it's greatly appreciated. There's no need to denegrate someone else's work just because it won't win the Nobel prize.

camdigger
10-15-2010, 03:24 PM
Isn't this in part what HSM is about? Like most of us haven't spent time and effort building something that could be bought for half the cost. But what fun is that? And if you can make it better than the original - even more fun.

I think these discussions are great. Even the bickering is entertaining.

Tom

The pursuit and sense of accomplishment are typically the only rewards, but read back a few posts where Evan has promised to torpedo Gearotics who originated the idea, developed, executed and are now trying to market it by making his reverse engineered program available to all who are interested.

Yeah Evan, the guy who refused to believe the precision gear finisher used a true hob profile grinding wheel, believing instead it was a stack of wheels:rolleyes:

And you guys bitch about the Chinese morals and ethics?:rolleyes:

Evan
10-15-2010, 03:27 PM
edited by self

Evan
10-15-2010, 03:38 PM
This is what I had to say about Gearotic:


When I find time I will write a plugin for CamBam to generate the code for simple spur gears. That may be awhile and it won't compete with Gearotic as it won't have the range of capability that Gearotic does. The gearotic program is very cool and I have only found one way to crash it so far. That is probably already fixed. $75 is a good price.

http://bbs.homeshopmachinist.net/showthread.php?t=43810&page=2

John Stevenson
10-15-2010, 04:02 PM
I haven't claimed to be breaking any new ground here. If you read the original post you will see that a very similar process was patented at least 40 years ago.

A little bit longer than that Evan,
If you read the Gears, gears and more gears post I make reference to the Sunderland planer machines, invented by Sam Sunderland in 1892 that plane gears by the facet method.

I even posted a you tube video of the process.

As good as what you have done you are only mimicking what has passed before.

In fact how do we even know you have done this given that you have a working beta copy of the Gearotic program ??

.

dp
10-15-2010, 04:33 PM
Another good thread gone into the sh!tter because of petty bickering.

Evan
10-15-2010, 05:03 PM
In fact how do we even know you have done this given that you have a working beta copy of the Gearotic program ??


You are being a fool John. That is the single dumbest thing you have posted in a long time.

Does this look like Gearotic code?




G90
F200
#1000=0
F5
G0Z.125
G0Y0X0
G01Z-.1377

F5
G0Y0
F200
G91F200
G01 X-.2 A 7.5
G01 X-.2 A -7.5
G01 X.2 A 7.5
G01 X.2 A -7.5
G90

G00a[5.614+#1000]
G01 F5 Y.0313
G91F200
G01 X-.2 A7.5
G01 X-.2 A-7.5
G01 X.2 A7.5
G01 X.2 A-7.5
G90

G00a[13.123+#1000]
G01F5Y.085
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[20.478+#1000]
G01F5Y.1377
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[25.804+#1000]
G01F5Y.176
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G0a[29.993+#1000]
G01F5Y.2062
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[33+#1000]
G01F5Y.2277
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[35.732+#1000]
G01F5Y.2474
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[38.564+#1000]
g01 f5 y.2675
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[41.412+#1000]
G01F5Y.2882
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[44.313+#1000]
G01F5Y.3088
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

(OPPOSING FACE)

G00a[-5.614+#1000]
G01F5Y-.0312
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[-13.123+#1000]
G01F5Y-.085
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[-20.478+#1000]
G01F5Y-.1377
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[-25.804+#1000]
G01F5Y-.176
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G0a[-29.993+#1000]
G01F5Y-.2062
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[-33+#1000]
G01F5Y-.2277
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[-35.732+#1000]
G01F5Y-.2474
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[-38.564+#1000]
G01F5Y-.2676
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[-41.412+#1000]
G01F5Y-.2882
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90

G00a[-44.313+#1000]
G01F5Y-.3088
G91F200
G01X-.2A7.5
G01X-.2A-7.5
G01X.2A7.5
G01X.2A-7.5
g90
(NEXT TOOTH)


Run it youself and see what it makes.

The fact is that I don't even know what the Gearotic code looks like. I never even used it to generate any code.

Evan
10-15-2010, 05:13 PM
Another good thread gone into the sh!tter because of petty bickering.


This is much more than petty bickering Dennis. On many other forums both Camdigger and John would be banned for such posts.

In particular, John is now insinuating that this entire thread by me is outright fraud. That doesn't say much for his integrity, does it?

John Stevenson
10-15-2010, 05:33 PM
This is much more than petty bickering Dennis. On many other forums both Camdigger and John would be banned for such posts.

In particular, John is now insinuating that this entire thread by me is outright fraud. That doesn't say much for his integrity, does it?

Integrity ??

I go to the trouble of getting permission to send you a working copy of the program and you have the balls and nerve to reverse engineer it just so you can crow about it.

Nowhere did I say it was my program only that I was testing it, what went on as regards development of spur and helicals is between me and Art, never mentioned, never will be but Art and I go back a long way.
Run Mach3, hit help about and read the credits list.

I shave been up front with my involvement and the history of the process, it's not new as many have pointed out but as far as I am concerned you have sht on what Art and myself have done and YOU have the gall to call MY integrity into play.

I hope that not only does this post get locked it gets removed.

.

Evan
10-15-2010, 05:41 PM
I go to the trouble of getting permission to send you a working copy of the program and you have the balls and nerve to reverse engineer it just so you can crow about it.


I didn't reverse engineer it. The way to do this is obvious to anybody with some math skills.


I shave been up front with my involvement and the history of the process, it's not new as many have pointed out but as far as I am concerned you have sht on what Art and myself have done and YOU have the gall to call MY integrity into play.


Are you still accusing me of FRAUD John?

What I have done it take what YOU have explained is nothing new and implemented it my own way.

BTW, the program itself doesn't give any clue how to do this. What immediately made it clear was the video of how it cuts. I never bothered with the program after playing with it for a few minutes and finding the crash bug I sent you so it could be fixed.

clutch
10-15-2010, 06:19 PM
I'm curious to hear how long Evan spent mimicking the what the Gearotics software does. The Gearotics software is a $75 plugin. How many hours at what hourly rate are you willing to assign the reverse engineering of an existing product?

I don't care how many hours Evan took. Money isn't likely his impulse. I suspect it was one of 'I can do that' and thank fully he has made efforts to explain his thoughts on it.

Clutch

precisionmetal
10-15-2010, 06:27 PM
Not counting the square profile at the root, why not cut the profile in one pass with the gear mounted horizontally?

You mean like this?

OK... I cheated. Cut in my wire edm machine. :)

It's 254 DP (0.1 module) - 20 degree PA. Cut from a piece of .025" thick Starrett shimstock.

I'm generating code to do this using yet another method... my implementation, but not my own creation by any means. Not too different though than what's been done by Gearotic, Evan, or probably many others. Just another way to skin the cat.

And yes: that is a normal penny.


I commend the Gearotic guys, Evan, and anyone else who takes the time to do something different, or new, or old, or simply for themselves, or anything else. Making stuff is fun, and essentially that's why most of us are here!

http://wire-edm.com/temp/254dp20.jpg

clutch
10-15-2010, 06:42 PM
The most interesting thread on this forum I've seen in years, John posting real world results using something I could own and put to use and Evan going into the thought process of creating a spur gear. What is not to like?

I can't tell what took place recently since I see a number of edited threads but at some point, it seems like camdigger had to toss in some willy pete just to light things up.

It was a sad day when you left the stage for a while Sir John and sometimes you, Evan can be a bit of a irritation since you are so sure of yourself, but on balance, the two of you post some of the most interesting content on this forum.

Can't you two just get along? Evan is more like a the professor and you, Sir John, play the role of the master craftsman.

Either one of you could swap places if inclined to do so and few would notice.

I hope this was not fuel for the fire but oil to calm the waters. You are both exceptional, please do not take exception.

Clutch

ADGO_Racing
10-15-2010, 06:46 PM
The pursuit and sense of accomplishment are typically the only rewards, but read back a few posts where Evan has promised to torpedo Gearotics who originated the idea, developed, executed and are now trying to market it by making his reverse engineered program available to all who are interested.

Yeah Evan, the guy who refused to believe the precision gear finisher used a true hob profile grinding wheel, believing instead it was a stack of wheels:rolleyes:

And you guys bitch about the Chinese morals and ethics?:rolleyes:

For what it is worth, when I first read this thread this morning, my thought was "Evan is out to show his superiority again". Copying/duplicating (whatever you want to call it) the work of others. I bit my tongue (fingers) when I saw others kissing his highness's butt, for plagiarized work.

gwilson
10-15-2010, 06:51 PM
This forum has turned into a very unpleasant bunch of constant jealousy and bickering between a bunch of irascible old GAMMELFIESCEN!!!

I respect what Evan does,and think that he has a great deal of knowledge to offer. What the problem with NICK,JOHN,and CAMDIGGER is,I don't know,but you are certainly sounding like a group of a$$holes.

John Stevenson
10-15-2010, 07:00 PM
I respect what Evan does,and think that he has a great deal of knowledge to offer. What the problem with NICK,JOHN,and CAMDIGGER is,I don't know,but you are certainly sounding like a group of a$$holes.

What problem ~?

I go out of my way to show in real world terms setups and different ways of doing things when I don't have to.
Perhaps the recent busy spell when I was absent and I managed to catch up on a lot of things should have told me something.

Like look after number one first ?

Tony Ennis
10-15-2010, 07:01 PM
Nice job Evan!

jkilroy
10-15-2010, 07:25 PM
Personally, this is a great thread and EXACTLY why I come to this site AND subscribe to the magazines the support the site. The petty bickering is tiresome, but the newfound IGNORE list is, like Tony the Tiger says, Grrrrrrrreeaat! I sure wish I had a smallish 4 axis mill! This stuff would be really fun to play with.

Oh, that EDM gear is fantastic. I have read, and generally believe, that a lot of the parts for high end custom watches are produced via EDM these days, perhaps this part is for something like that?

rohart
10-15-2010, 07:26 PM
Well said, Clutch.

John should understand that the Gearotics program has the great advantage over anything else around of being a working tested package.

Evan has taken some of what Gearotics does as inspiration, and by replicating its results is showing us how this stuff works, and what else could be done. If he's sitting beside large lumps of accurately cut glass, I'm pretty sure that the developer of Gearotics has nothing to fear. He won't be putting up a working package with a fully fledged interface anytime soon.

Cam should try to see things as Flat put them. HSMers are driven to waste their time doing stuff their own way. People with a software background do the same thing in their own field.

I use my own homegrown image editing and text editing software. I wouldn't dream of using what I regard as crappy rubbish like photoshop. I'm sure it hasn't got me anywhere in life, but I hope no one throws stones at me for doing so.

Evan
10-15-2010, 07:27 PM
I bit my tongue (fingers) when I saw others kissing his highness's butt, for plagiarized work.


You can't "plagiarize" mathematics and the idea doesn't belong to Art Fenerty.

As for John, he is upset because I am pissing on his fence posts again.

Evan
10-15-2010, 07:35 PM
and by replicating its results is showing us how this stuff works, and what else could be done...

I have already had some ideas that this technique makes possible. One is gears that have a curve to the teeth instead of a herringbone pattern. That should provide an even smoother mesh while still being self centering. If Art wants to put it into Gearotic I haven't the slightest objection. I also have no objection to people using any of the many ideas I have posted here. That also includes any of the photographs that I post.

camdigger
10-15-2010, 07:39 PM
I respect what Evan does,and think that he has a great deal of knowledge to offer. What the problem with NICK,JOHN,and CAMDIGGER is,I don't know,but you are certainly sounding like a group of a$$holes.

I can only speak for myself, but I seem to see things a bit different than some others.
As for the relationship between Evan and myself, he has taken numerous potshots at me, my reputation, and profession at various times for no other apparent reason than to stir crap and get a reaction.

In light of that, he and his fan club should be prepared to be called on what appears to be less than scrupulously clean reverse engineering. Stone throwers and glass houses....

You might not be able to plagarize math, but concepts, yes. That Evan made his own gear for his own use - minor kudo.

That he proposes to release low cost or free competition for the originator in any language or format after receiving all the examples shown by John and even a Beta copy of the program in question smacks of moral bankrupcy.

Just exercising my right to my opinion.

gwilson
10-15-2010, 07:43 PM
Don't you guys think that us fellow machinists could be a bit nicer to each other? First that outburst from Mullernick,and now this.

Weston Bye
10-15-2010, 07:52 PM
Looks like this thread has run its course. You guys have anything else HSM useful or informative to post? Evan? John? Anyone? Bickering got another otherwise decent thread locked, could happen again...

Hope not.

.RC.
10-15-2010, 07:54 PM
http://img.photobucket.com/albums/v606/OzRinger/popcorn.gif

Evan
10-15-2010, 07:54 PM
As for the relationship between Evan and myself, he has taken numerous potshots at me, my reputation, and profession at various times for no other apparent reason than to stir crap and get a reaction.

Show even one example of that where you didn't start the pissing contest and I will show ten where you began it.


That he proposes to release low cost or free competition for the originator in any language or format after receiving all the examples shown by John and even a Beta copy of the program in question smacks of moral bankrupcy.


So is that kind of like having 50 different CAD programs on the market and all but one are created by morally bankrupt programmers? I haven't used the beta copy john sent me and don't need it either. I didn't copy it and the method isn't proprietary. My version when I get around to making one won't be competition and it will be free so I have no fiduciary interest in this subject. The Gearotic software itself cannot be patented either nor can the code it produces which I haven't even seen yet.

Seems to me you have some other problem.

camdigger
10-15-2010, 07:55 PM
Don't you guys think that us fellow machinists could be a bit nicer to each other? First that outburst from Mullernick,and now this.
I am being nice.

You'll notice if you care to look, I didn't say "I told you so" once in Evan's biannual "pity me, the fires are coming!" thread after I tried to point out to him earlier that fire resistant exterior surfaces are within BC safety code and are not prohibitively expensive...:rolleyes:

I won't even mention the multiple slanderous innuendos in the oil leak thread..:rolleyes:

Evan
10-15-2010, 08:07 PM
You don't live in a forest so I can understand why it wouldn't seem like that much of a threat. I can't afford to reside my house at present nor would it help in a raging crown fire. The danger was very real as we were only two kilometers from the evacuation zone.

I posted no "slanderous comments" in the oil thread. Also, slander refers only to the spoken word. :rolleyes:

dp
10-15-2010, 09:25 PM
This is much more than petty bickering Dennis. On many other forums both Camdigger and John would be banned for such posts.

In particular, John is now insinuating that this entire thread by me is outright fraud. That doesn't say much for his integrity, does it?

He's a decent machinist with a thuggish personality. One does not compensate for the other. The acrimony here goes up when John returns from one of his sabbaticals. He's rather like the elephant in the room, at times. Camdigger's in my bit bucket.

camdigger
10-15-2010, 10:20 PM
You don't live in a forest so I can understand why it wouldn't seem like that much of a threat. I can't afford to reside my house at present nor would it help in a raging crown fire. The danger was very real as we were only two kilometers from the evacuation zone.:

I do not have to live in a forest to have an appreciation for fire safety. It is a major consideration in some of the operations I've been involved in.

In the case of a crown fire the few thousand gallons of water you have available at the rates you can apply them are a waste of time too. Obviously you think you can do something with those.:rolleyes:


I posted no "slanderous comments" in the oil thread. Also, slander refers only to the spoken word. :rolleyes:

Semantics. General idea is the same.

I'm so glad you've evolved from the playground class name calling you used to resort to when caught.

RKW
10-15-2010, 10:36 PM
It always seems to involve some of the same folks competing to demonstrate their knowledge or get in the last word. What I can't figure out for those who seem to know everything, why hang out on a forum?


Looks like this thread has run its course. You guys have anything else HSM useful or informative to post? Evan? John? Anyone? Bickering got another otherwise decent thread locked, could happen again...

Hope not.

Evan
10-15-2010, 10:46 PM
In the case of a crown fire the few thousand gallons of water you have available at the rates you can apply them are a waste of time too. Obviously you think you can do something with those

You just proved that you don't know anything about fire fighting either. The water is (was) to put out spot fires from embers blowing in our direction. That is how most fires advance.

J Tiers
10-15-2010, 11:04 PM
I think the herringbone gears are pretty cool......

They "almost' make me think about converting a machine to CNC..... But I don't have time, and I have other things to do. I have, at last count, 8 hobbies, and only one day at a time to indulge them...... plus I work. And, I'm not going to buy a new CNC machine of any sort, not sensible for me.

Doesn't mean I can't appreciate neato gizmos.

The little gear is neat too.

Just to stir that pot, now you have the spindle gear, where's the rest of the lathe that itty bitty gear fits on? :D :eek:

camdigger
10-15-2010, 11:09 PM
You just proved that you don't know anything about fire fighting either. The water is (was) to put out spot fires from embers blowing in our direction. That is how most fires advance.

Exactly where fire resistant exterior finishes would be invaluable. A point I tried to make oh so long ago.:rolleyes:

Your response at the time was to shift to crown fires. Now we go the other way.

Yawn, it's time to put the kids to bed.... TTFN

Evan
10-15-2010, 11:39 PM
Well, once again you accomplished nothing worthwhile. It really must be rewarding. I am curious about one thing though. Have you ever actually made anything in a machine shop? I don't recall you ever posting anything to do with home shop machining.

lazlo
10-15-2010, 11:56 PM
You mean like this?

OK... I cheated. Cut in my wire edm machine. :)

It's 254 DP (0.1 module) - 20 degree PA. Cut from a piece of .025" thick Starrett shimstock.

http://wire-edm.com/temp/254dp20.jpg

Wow, that's slick! So you're generating G-Code straight from the formula for an involute curve? What step size did you use?

Does G-Code support B-splines? Meaning, you define a curve with N points, and the CAM controller generates as many discrete steps along that curve as the X- and Y-axis are capable.

As Lew has pointed out before, the involute curve is a smooth curve with only 3 transitions (maybe 4 for the final curve on an undercut tooth).

How long did that take to burn?

camdigger
10-15-2010, 11:56 PM
Well, once again you accomplished nothing worthwhile. It really must be rewarding. I am curious about one thing though. Have you ever actually made anything in a machine shop? I don't recall you ever posting anything to do with home shop machining.


Just because you're so busy patting yourself on the back, you haven't noticed.:rolleyes:

FYI, one of the threads I posted some work in is the shop made tools, and, and, and..... Proof positive of the first point I made in this post.

I tend not to post much shop work because 1. the attack troll factor especially from Williams Lake, 2. I work full time plus, and 3. I find the picture posting routine here a PITA.

Nice work on the redirection/misdirection deftly avoiding recognizing the trap you set for yourself in the previous two posts. Or the question re the time spent replicating a $75 plug in a Beta copy of which you were given in good faith and felt entitled to rip off:D :D

Deja Vu
10-15-2010, 11:58 PM
All this jabberwocky about stepping on another's foot(or somethin') is all entertaining and such, but I've(Bloy) entered Gearotic's video contest with hopes to merit a complimentary program. Then I can fiddle with assembling some sort of sturdy 4th axis with which to cut a special gear. Actually, two gears...of differing diameter fastened/bonded together. I think I may need other tooling If I were to attempt a single highly stepped gear combo.
Anyway, Here's what I've done(virtually) as a possible contender!:D
http://www.youtube.com/watch?v=yS1C7AfXvY4 (http://www.youtube.com/watch?v=yS1C7AfXvY4)

I'm just glad the things John S has posted over in Gearotic.com aren't entered. I wouldn't stand a chance. But then, he's already got the full blown program. ;)

edit in...I forgot to ask..is friday show 'n tell day?:rolleyes:

Black Forest
10-16-2010, 12:27 AM
DeJu Vu. What software did you use to animate your gears?

Deja Vu
10-16-2010, 12:36 AM
DeJu Vu. What software did you use to animate your gears?

It's right in the program. After you create your "scene", you click to make the video. Then, you simply upload it to Youtube and use that link to post in the contest entry thread.

I should add...
The gearotic program chooses your first gear placement as the driving gear and the program controls allow you to adjust speed, size, angle of the scene. It saves the short video in the programs installation folder.

ADGO_Racing
10-16-2010, 12:36 AM
As for John, he is upset because I am pissing on his fence posts again.

Precisely what I thought! Thanks for admitting it in public.:D

Black Forest
10-16-2010, 12:42 AM
It is right in the program..........what program?

Black Forest
10-16-2010, 12:44 AM
DeJu Vu, you must have edited your post as I was asking what program!

So I take it you can create a video of your gears in this Gearotic software.

precisionmetal
10-16-2010, 12:45 AM
Wow, that's slick! So you're generating G-Code straight from the formula for an involute curve? What step size did you use?

Does G-Code support B-splines? Meaning, you define a curve with N points, and the CAM controller generates as many discrete steps along that curve as the X- and Y-axis are capable.

As Lew has pointed out before, the involute curve is a smooth curve with only 3 transitions (maybe 4 for the final curve on an undercut tooth).

How long did that take to burn?

Lazlo,

I'm still using a CAM program to generate the G-code.

I do some gear calcs first, then essentially create a single tooth flank profile which is ultimately converted to arc sections that are all perfectly tangent to each other at the ends. (I can tweak how many arc sections I use in order to stay within "X" distance of the theoretical involute form). Then I drop that profile into my CAD program and do the rest of the work there, which typically involves adjusting things near the bottom of the profile in order to meet the required TIF diameter, adding tip radius and root fillet (the root fillet needs to be larger than half my wire size plus the offset I'm running), and then turning that all into a full gear profile and making sure the entities all chain up correctly (sometimes easier said then done).

After that's done, then into the CAM program to generate the code for the wire machine.

Sometimes the above process goes very quickly, and sometimes it's a back and forth deal that can consume a significant amount of time. Much of what I do involves gear "pairs" (gears almost always run against another gear in the real world, after all :) ). Working off someone else's design where there may be a center distance tolerance as well as a backlash tolerance, not to mention a tolerance in the mating gear (if I didn't make it) can add up to a fair bit of time.

The wire machine is so accurate that the cutting is usually the simplest part of the job.

To answer your question about steps -- since I'm using arc sections, the best answer I can give on this gear comes down more to the position increments of the machine, which is 1 micron. Since the teeth in that gear are just under .009" deep, it's probably safe to assume that the machine made around 200-250 "moves" to do one flank of one tooth. Ultimately what's happening though is that the machine is doing circular interpolation, so geometrically there are only a few "commands" to form one tooth flank, but the machine is making lots of very minute moves to accomplish that.

The time to cut that gear was around 30 minutes (around 10 minutes for the bore and 20 minutes for the teeth). That includes threading the wire twice. Very tiny wire (70 micron), so can't put much power to it!

PM

Deja Vu
10-16-2010, 12:59 AM
DeJu Vu, you must have edited your post as I was asking what program!
i guess so


So I take it you can create a video of your gears in this Gearotic software.
Yup. What you see from the link above of one of my entries is made with Gearotic.

Deja Vu
10-16-2010, 01:08 AM
precisionmetal
Have you posted pictures of your EDM anywhere on the web that can be viewed? Otherwise, I'd sure like to see a picture or two of that machine.
Maybe the manufacturer has multiple details of it....

Evan
10-16-2010, 02:06 AM
Nice work on the redirection/misdirection deftly avoiding recognizing the trap you set for yourself in the previous two posts. Or the question re the time spent replicating a $75 plug in a Beta copy of which you were given in good faith and felt entitled to rip off

Do you have any idea what source code is? Without source code it isn't possible to determine how software is programmed without going to extreme lengths and by the use of a good deal of specialized software.

I gave up on the beta copy John gave me because it is broken. It won't do anything more than display a low res wire frame view. I never bothered to create any G code so the idea that I "ripped it off" is ludicrous. Further. If you actually knew anything about G-Code you would realize that the code I posted does what I say it does and isn't machine generated. I haven't "replicated" any program at all. You are utterly clueless and should stick to something you know about, whatever that is.



Precisely what I thought! Thanks for admitting it in public

You obviously don't understand what I meant. John likes to think of himself as the ultimate authority on CNC and gears. He is pissed because I am, in his mind, encroaching on what he likes to think is his divinely granted territory.

camdigger
10-16-2010, 05:03 AM
Nice gear PM

I can't wait to get back to the big city to watch the video!

camdigger
10-16-2010, 05:09 AM
Do you have any idea what source code is? Without source code it isn't possible to determine how software is programmed without going to extreme lengths and by the use of a good deal of specialized software.

I gave up on the beta copy John gave me because it is broken. It won't do anything more than display a low res wire frame view. I never bothered to create any G code so the idea that I "ripped it off" is ludicrous. Further. If you actually knew anything about G-Code you would realize that the code I posted does what I say it does and isn't machine generated. I haven't "replicated" any program at all. You are utterly clueless and should stick to something you know about, whatever that is.




Code, schomde. Generating code for anything should be a trivial matter for someone with 47 years programming experience.;) Still avoiding the time question, huh?

Why is it you have to insinuate someone "knows nothing" when their opinion differs from yours?:confused: Even when I try to help you, you become antagonistic. Hmmm, self esteem issues?

Evan
10-16-2010, 05:19 AM
One thing I haven't mentioned camdigger is that you have been giving me entirely too much credit as a programmer even though I haven't yet done any programming on this matter. Crediting me with the ability to reverse engineer a compiled program is a high compliment indeed. That is far beyond my ability and knowledge of X86 machine code structures. Trying to infer how a program is structured from the compiled code is a job for the very elite among programmers. In many cases it is nearly impossible. Trying to deduce it from the resulting output is just as difficult and often impossible since there are an almost unlimited number of ways to arrive at the same end result.

In this case if you simply watch the video of the Gearotic program in action compared with mine it is clear that I have taken a very different approach to the problem. The Gearotic cutting sequence and mine are completely different with the gearotic sequence being more efficient but with mine taking double passes on all cuts. That alone sets the techniques apart considerably since my approach should produce a better finish while the Gearotic sequence is faster.

camdigger
10-16-2010, 05:25 AM
One thing I haven't mentioned camdigger is that you have been giving me entirely too much credit as a programmer even though I haven't yet done any programming on this matter. Crediting me with the ability to reverse engineer a compiled program is a high compliment indeed. That is far beyond my ability and knowledge of X86 machine code structures. Trying to infer how a program is structured from the compiled code is a job for the very elite among programmers. In many cases it is nearly impossible. Trying to deduce it from the resulting output is just as difficult and often impossible since there are an almost unlimited number of ways to arrive at the same end result.

In this case if you simply watch the video of the Gearotic program in action compared with mine it is clear that I have taken a very different approach to the problem. The Gearotic cutting sequence and mine are completely different with the gearotic sequence being more efficient but with mine taking double passes on all cuts. That alone sets the techniques apart considerably since my approach should produce a better finish while the Gearotic sequence is faster.

Learning by experience to buld a better mousetrap... still an idea that has been duplicated after a road map been laid.... Not going to change that.

Blah, blah, blah.

That you replicated it thumbs up to you. With 47 years programming experience, still should be a trivial matter.


That you intend to release/propagate competition to those who provided the stepping stone, not so commendable.

If you can't see that, shrug......

philbur
10-16-2010, 05:41 AM
A couple of spur gears together with a cam shaft and cutting tools I made a number of years ago. It's probably the simplest method for the HSMer as it requires no special involute cutters or form tools or 4 axis CNC. The form tool and rotary cutter have a straight sided rack profile and are simple to make on a mill, a lathe and an indexing arrangement.

http://i186.photobucket.com/albums/x36/philbur/camandgears1.jpg

Phil:)

PS: You only need one rotary cutter for any one module/dp. I don't remember why I made 2.

Evan
10-16-2010, 05:43 AM
still an idea that has been duplicated after a road map been laid....


You still don't get it. This is what the program looks like inside. Not exactly a road map to anything.

http://ixian.ca/pics8/code.jpg


Blah, blah, blah.

How enlightening.


That you replicated it thumbs up to you. With 47 years programming experience, still should be a trivial matter.


I haven't replicated anything since I haven't programmed anything. I hand wrote some linear G-code with no reference to anything else. That's obvious from the differences in operation. That isn't programming. I have used the same idea that others have before including Art Fenerty. You have too every time you design a well.

camdigger
10-16-2010, 05:47 AM
Nice gears Phil!

Hmmm, a gear pair of roughly 2:1 ratio (didn't count the teeth - too lazy, I guess), and a lobed camshaft...

Must be building an engine? Is it posted somewhere? ie can I see it?

How hard was it to generate the lobes on the camshaft?

camdigger
10-16-2010, 05:54 AM
You still don't get it. This is what the program looks like inside. Not exactly a road map to anything.



How enlightening.

Another shot and a clean miss....

Cue Foghorn leghorn audio encoder... The point that is... audio encoder off.


Again, duplicating the results should be trivial with 47 years programming experience...

That you can do it... yawn.

That you intend to release competing software with the original innovator after the leg up you got...

Can't believe you don't get it...

None so blind as those who will not see...

Evan
10-16-2010, 06:03 AM
You still fail to understand. I gained nothing from playing with the program since it gives no clue as to it's operation. What instantly gave me the same idea as Art was watching the first ten seconds of the video on you tube.

So, by your interpretation anything that somebody creates from first principles that resembles something somebody else created is somehow unethical. There is an entire industry that exists on the premise that you are wrong. It is the software industry. Or the automotive industry. Or just about any industry that produces just about anything.

camdigger
10-16-2010, 06:39 AM
You still fail to understand. I gained nothing from playing with the program since it gives no clue as to it's operation. What instantly gave me the same idea as Art was watching the first ten seconds of the video on you tube. .

You gained nothing but the inspiration and a significant amount of info even from the work John posted.


So, by your interpretation anything that somebody creates from first principles that resembles something somebody else created is somehow unethical. .

Not if it is for your own use and remains so. Especially in light of the advantage of watching the progression/evolution of the concept and idea. Gawd are you really this dense?


There is an entire industry that exists on the premise that you are wrong. It is the software industry.
Bad example. That industry has been stealing ideas from one another since the beginning... They sue each other now and then over the stolen ideas. BTW, the guy with the biggest bank account usually wins:rolleyes:

As an exception which proves the rule, within the last year Microslop paid a court ordered 7 figure settlement in a suit over STOLEN code for Word 7, IIRC...

Your use of that particular industry as an example hints at where you got your sense of morality re this kind of thing. Explains a lot, actually.


Or the automotive industry. . There's a reason why prototyopes in the auto industry are cloaked right up until models are released - TOO PREVENT COPY CATTING aka industrial espionage.


Another clean miss.....