Bevel Gear Instructions

.... "Before I invest in an upgrade to WF3, I want some assurance that the current available method can be successfully used at high PCAs, above 45°."

There's a reason AGMA has gear making software ~ specialized software, dedicated to only gear design ~ that it supports and recommends and that gear makers/gear designers generally use over the generalist, "one-size-fits-all" approach of a Pro/ENGINEER. Pro/e is kinda good at a lotta things but REALLY good at nothin'.

Seems like you're wanting to buy in early, get all the benefits of the new software and all the improvements. Be good to know, before you go, what all those "improvements" are and how they relate to gear design.

The bug you mention (flipping stuff, inside/outside, top/bottom, left/right) is a perennial favorite with Pro/e: climb the mountain, from 2001 to WF, get over a bunch of hurdles, "correct" a bunch of bugs, then, come back to WF2, F000_, and find the same stuff you thought got fixed in the previous rev. THEY BEEN DOIN' THAT SCAM FOR A L-O-N-G TIME!!! No building on the "shoulders of giants" where PTC is concerned; rev ending points are hardly ever new rev starting points, where Pro/e is concerned. The big guys (Motorola, Caterpillar, OMC, Deere) simply play the waiting game and buy a rev when it's been improved to its limit, which is when it is just about to expire and the new, "IMPROVED" rev is about to step in to take its place. The SE is the perfect bench mark, as it's released with the first commercial version of Pro/e and reflects its native state. Bugs you find in it are in the native, initial released software; wait 6-9 months and you'll be much better off. If you insist on jumping in early, be prepared to participate in the bug report, improvement report, new build testing every week, data collection/reporting and the whole, after market, beta-gamma testing (you'll never hear, officially, about this, but you'd be an elite participant). Anyway, whatever, the problem may be in your original surface models and could be fixed, quite simply, by redefining them which might get all those internal arrows flipping in the right direction. I've noticed, since WF, that Pro/e can't tell the simplest thing about direction and this is the single biggest weakness of the Dashboard ~ the interface is nicely revamped but the code at the base is the same dimwitted shit. That's what your problem sounds like. And you need to get into the bug reporting/tracking/correction process. We'll all be better off if a bunch more people do.

David Janes

David,

obviously there´s some elementary math (+/-) in the ProE core not well implemented - impossible to fix (fixes generate no cash).

Since this was an issue back in V12 I guess it will never be fixed, maybe we´re luckier with programmers frequently inventing new GUIs. Leaves us with the behaviour of the core modeller predictable.

Walther

Yes, Walter, there's something to be said for not "fixing" known bad behavior. It's the origin of Pro/e as the capital of the workaround universe. I just don't know a workaround for this one. But to actually fix this 'by mail' which is how we work here, we'd have to get into the actual modeling methods. Some are more susceptible to the "flipping" problem than others, especially if a pattern is involved. Any more details that can be provided on the construction will be of use.

David Janes

This is not, repeat not, meant to run as a gear design method. It only generates a toothed model for assmbly fit and fuction.

The original models were developed in ver. 2001. These did not have this problem. Those original models work well in in WF2. Pitch Cone Angles for 2:1 and up ratio gear sets can be created without any problems. The new methods employed only simplfiy and remove some of the steps due to some new relations.

I would greatly appreciate some input without the cynical baggage attached.

I invite anyone to try and build a test model in WF3 and report any findings regarding this issue.

The failure occurs when the template's Pitch Cone Angle is pushed into the 2:1 ratio area, approximately 68 degrees.

As far as jumping on the bug band wagon, my current employer does not use Pro/ENGINEER. I do like the program very much and keep the personnal copy for my own use (no maint).

Thank you, Mark N. McAllister

David Janes wrote:

"This is not, repeat not, meant to run as a gear design method. It only generates a toothed model for assmbly fit and fuction."

Okay, some nice red-herring reply to some non-existent suggestion of some alleged production use of your models. Got NO idea WTF you're talking about or reacting to since you seem strictly averse to quoting (anything or anyone), so we have no reference, no attribution for anything. Too bad, cuz we might at least have gotten your "rewrite of instructions to build Straight Tooth Bevel Gears" out of this whole process. And, as we've NEVER had that here, it would have been quite a coup, quite a contribution on your part, Mark. But, so far, we've gotten only hints, suggestions, inferences, rumors, vague references to such a thing.

"The original models were developed in ver. 2001. These did not have this problem. Those original models work well in in WF2. Pitch Cone Angles for 2:1 and up ratio gear sets can be created without any problems. The new methods employed only simplfiy and remove some of the steps due to some new relations."

So you allege; we haven't seen them or their progeny. But, in this forum, with a bunch of highly skilled Pro/e Super Users, we'd have to actually see and interrogate and investigate the patient to make a diagnosis

I would greatly appreciate some input without the cynical baggage attached.

I invite anyone to try and build a test model in WF3 and report any findings regarding this issue.

Are we now privy to some private discussion, one to which we've not been previously invited? This, once again, unattributed "quote" comes from no discussion that's gone on in this forum. How does it get in here, with no introduction. I say it ought to be banned; I say it was introduced without foundation in fact; I say it's illusion, chimmera, shadows on the wall; spooky stories to scare little children. And, since we're adults here, please disregard. Mr. Mark N. McAllister was merely having another of his episodes. Please understand and be patient.

"The failure occurs when the template's Pitch Cone Angle is pushed into the 2:1 ratio area, approximately 68 degrees."

Could we retrench, regroup, reconnoitre and reassess: what is the failure we really have to deal with? So far, it looks only like this: "The surface merge feature's reference direction flips when the Pitch Cone Angle (PCA) is greater than 45°." Cool, but isn't there an arrow that lets you flip it back and correct the obviously incorrect regen from Pro/e!?!

"As far as jumping on the bug band wagon, my current employer does not use Pro/ENGINEER." So, how would you ever go to WF3!?! (This is in the half of what you've said, so far, that makes absolutely no sense!!)

"I do like the program very much and keep the personnal copy for my own use (no maint)." So what do you and your company use!?! And what's Pro/e got to do with it? Mysteries abound here.

David Janes

Mr. Janes, Nice rant.

David Janes wrote:

Apparently you did not realize I was referring to your comment in your initial reply. I will quote it here now. "There's a reason AGMA has gear making software ~ specialized software, dedicated to only gear design ~ that it supports and recommends and that gear makers/gear designers generally use over the generalist, "one-size-fits-all" approach of a Pro/ENGINEER. Pro/e is kinda good at a lotta things but REALLY good at nothin'.

Seems like you're wanting to buy in early, get all the benefits of the new software and all the improvements. Be good to know, before you go, what all those "improvements" are and how they relate to gear design."

As for the "highly skilled Pro/e Super Users", their analytical minds would have read the original post in its entirety and noticed at the bottom the following: "Has anyone tried the old method with any success in WF3? For those of you who want to try, the PDF is located at briefcase.yahoo.com. Login as: fromhenrik Password is: engineer Any light on this matter would GREATLY be appreciated."

This was set up by someone who assisted me once. I have discovered that others use the site now for Pro/ENGINEER related transfers.

If people who frequent ConnectPress's Pro/E community, specifically the Q&A section, also come here, they may have seen the original calls for help on this type of gear creation a few months ago. I uploaded and made the briefcase public knowledge at that time. It was only afterwards, I discovered that my method fails in Wildfire 2. Upon checking the original, 2001, models I discovered they do not suffer the same fate, hence the call to find if the same problem exists in WF3.

But, from the reception I have received, I severely doubt any serious inquiries are posted and they go to another forum such as the one mentioned previously, which is screened.

The preceding statement indicates you have read and fathomed some of the subject matter in the reply. Please explain why you could not understand in your highly skilled Pro/e Super User mind the part immediately following your quote of mine? "Also, when this problem is fixed and the tooth is rotated about the Z-axis, the directions flip yet again. This prevents a full pattern from developing." After a certain amount of rotation, the normals change direction and the solid, please download and examine the document to fully understand, fails.

We use a mid-range solid modeler from a company that originally started with a 2-D product. I will leave you to speculate as to what.

The power of Pro/E is far greater than what I professionally use, so I keep the personal edition to test out ideas in my spare time.

Now a personal message for Mr. Janes, login to google and view my profile to get my email address. Email me and I will send you the 2001 (SE) files and the new instruction set. In this way, Dr. Janes, you can interrogate the patient.

Mark N. McAllister

Thanks, and I'm happy to see that it achieved its aim; somehow, even English teaching Engineers find their tongues under a good tongue lashing. But I am learning things, as well ~ read thoroughly, read between the lines and try very hard to read for meaning. For example, after reading your reply, your original again and all the documentary and evedentiary information, I finally solved the riddle which was based on the "Going to St. Ives" pattern: brief introduction, complexified body resembling much handwaving, followed by a simple question; it was the question, which was the point of your original message, that I didn't get. I got lost in the middle somewhere, probably in crisis over a) understanding and b) replying to/critiquing your 18 page article on gear design with Pro/e. (BTW, when I read that article in Gearing Technology maybe 5 years ago, it was a photocopy of a xerox of a thermofax and the photos were just smudges. Since I lived, at the time, but a couple miles from the magazine's offices in Elk Grove Village, Illinois, I went there and got a copy of the original. I think I still have it.)

Here is the answer to your original question which was, to paraphrase, can someone assure me that I'll be able to do in WF3 what was done in 2001. The answer is an unqualified YES, of course: Pro/e hasn't, over the years, lost functionality. It's just gotten changes of clothes, fresh coats of paint, some new handles and knobs while the underlying machinery has stayed pretty much the same for a decade. With Wildfire, I'd say that they actually did fix some outright embarrassments, such as the Draft functionality. It may have been no more than telling their programmer to find the loop that caused almost all requests for a draft feature to go through 10 attempts before finally letting the user have the draft. I called such functionality Pro/GOOFY, the joke module in Pro/e (google it; you'll find many instances). On the other hand, they sometimes traded one awkwardness for another with the "Dashboard" funcitonality, such as creating a composite curve. Another really goofy thing that it did was muddle the "red" and "yellow" sides of datums and "soften" the right hand rule. So, for example, what you thought before was red might not now be. I don't believe it did a strict one to one translation and that, too, could be the source of the "flipping" problem. For inherited files or for files that depend heavily on relations which can't account for plus/minus, left/right, inside/outside, up/down, red/yellow, positive/negative ~ so what happens when your -50 is a +50 in the new system: it flips to the other side of the datum. But, then, you just reverse the sign and problem solved, same as always, V18 (where I started) or WF3, SOS or SSDD. And, if you want to be really sure, get the WF3 SE, available from Journey Educational Marketing for $179 (reduced for English teachers, $99 if you are upgrading from WF2). See online:

On the other hand, there's the business of gears, gear geometry, gear making (which I did for years: hobbs, bevels, shapers, shavers, tooth grinders) and gear design (where Pro/e might conceivably get framed). I had some questions on this which a talented amateur might be able to answer: a.. The whole discussion has been framed around Pro/e's fidelity and precsion out to unmeasureable levels of producability or accuracy. Who cares, what is Pro/e being used for? No one is doing modality ("ringing"), no dynamics whatsoever, barely even statics. So, I repeat, on all this fussy 'true to form' ~ why? who cares? I suspect you agree? b.. Why is there absolutely NO discussion of crowned tooth bevels: I made Gleason gear and pinions sets which called out a particular crown length. Gear Shaving, Shaping and Grinding are all capable of producing crowned teeth on bevels. Everyone making bevel gear and pinion sets does crowned teeth (relieved at toe and heel) so that, with deflection (toward the heel), the stress is not localized and tooth breakage is reduced. Even with the most perfect tooth form in Pro/e, do you get "crowned teeth"? NO!?!?! So what's all this fuss about how "true" Pro/e is to perfect form? "Perfect form", without crowned teeth, is bullshit!!! c.. The only thing that the professional software does is tell you the missing ingredients: you tell it PD, PA and DP (or some such), then it tells you the rest, like CA, addenedum, dedendum and root angle, etc. This is stuff you need to set up a machine which produces the gear profile. On the Gleason Bevel Gear machines, this translates into roll of the carriage (so that the double set of planing tools {with pressure angle built in} leave the tooth, root and crown), stroke of the tool carriers and the speed of the workpiece, all controlled by gear ratios (stroke was controlled by postion on an eccentric slot). None of the accuracy of this depends on Pro/e or any gear design software. And Pro/e will NEVER (and was never meant to) provide the these ratios. If you were using wire EDM to cut the gear profile, the issue would be different; the profile in Pro/e would acutally be used to guide the wire. But professional gear design software just generates the ratios which get looked up for different machines and approximated with a set of compound gears (A*C/B*D), whatever is the closest but not an even number. Anyway, Mark, you know my email address. Just send the patient to Dr. Dave; I'd be happy, on our socialist medical system, to check 'er out, free 'a charge. Yabba dabba doo!

David Janes