Miter Gear Cutting

[benmychree]

Personally, I feel no embarrassment regarding anything that I have stated; I have worked at the machinist trade all my working life, nearly 55 years, served a state supervised apprenticeship and have operated a successful machine shop business for about forty years, and believe that my statements have been well informed and substantiated by written authority. I have never been good with documenting a project, I'd rather just get the job done with and out the door, and get paid for it!
I am going to re read the book, and urge you to read it as well. There is nothing wrong with disagreement, as long as civility is observed, as it has been thus far.

 

[Ray C]

Personally, I feel no embarrassment regarding anything that I have stated; I have worked at the machinist trade all my working life, nearly 55 years, served a state supervised apprenticeship and have operated a successful machine shop business for about forty years, and believe that my statements have been well informed and substantiated by written authority. I have never been good with documenting a project, I'd rather just get the job done with and out the door, and get paid for it!
I am going to re read the book, and urge you to read it as well. There is nothing wrong with disagreement, as long as civility is observed, as it has been thus far.

Be apprised, I come from a family of tradesmen and respect their lifetime of hard work -as well as yours. In the context of this exchange, your work experience is totally irrelevant. So far, I have posted and documented a process that describes the basics of miter gears and how to make a basic miter gear. The process is outlined in a book precisely cited numerous times. You have made statements indicating what I have presented is wrong but, you have not cited specifically what it wrong. -That's because nothing is wrong. The objectives, boundaries and limitations were stated up-front. In this regard, you are clearly demonstrating you don't actually read what is written. And in my world of professional engineering, you're allowed to make that mistake only once. This is getting old... Please... If you wish to convey different information about gears, do it in a thread of your own. You infer constructive criticism... Please point-out to me what is constructive about what you said. -And perhaps I should "undelete" some of your posts that the other administrators deleted. Please think before you post.

Ray

 

[12bolts]

Great write up Ray!

Cheers Phil

 

[Ray C]

All,

Enclosed is the PDF of "Practical Treatise on Gearing" that has been mentioned in the preceding posts. It is indeed a good read, very short of about 130 pages discounting the appendices of trig constants etc. I just finished reading the sections on spur and miter gears. The beginning parts of the book pertaining to spur and miter gears, appear to be similar in nature to the abbreviated/simplified content written here.

I believe in my write-up of spur gears, or perhaps somewhere earlier in this thread, it was mentioned there are many techniques and standards which may be used to modify the shape of a basic, involute gear. The paper "Practical Treatise on Gearing" appears to go into some of the early methods being considered on how to improve the shape of a gear tooth. Be apprised, the book has publish dates ranging from 1886 to 1911 and thus, the final version was written long before the SAE (and later AGMA) finalized the standards on gear tooth shape. In that timeframe for example, Whitworth threads (introduced in 1844 and ending about 1955) were still in use. I would be hesitant to recommend "Practical Treatise on Gearing" to learn about the now-advisable ways of modifying gear teeth. -And to be perfectly honest, I am not conversant on the latest developments there. I am a member of the IEEE and ASME -but there is only so many hours in the day to keep up on things.

To clarify once again, the techniques I conveyed in my thread were about basic miter gear geometry with a basic involute tooth surface. It makes a technically correct and perfectly functional gear for low speed use -much the same quality and efficiency as the change gears on your manual lathe.

Finally, my hat goes off to all the engineers of over a century ago, who sweat their brains out figuring this stuff out. I also respect the folks who toiled behind machinery trying to actually make the darn things.

Regards

Ray

 

[Eddyde]

Ray, Thanks for the excellent write up. I would have never thought possible to make such gears but after reading this I feel confident I could, if the need should ever arise.

 

[Ray C]

Ray, Thanks for the excellent write up. I would have never thought possible to make such gears but after reading this I feel confident I could, if the need should ever arise.

LOL: I don't normally give professional advice on public websites. My PE insurance underwriter doesn't appreciate it. For you Eddy, I'll break my own rule.

Here you go: McMaster-Carr https://www.mcmaster.com/#miter-gears/=1d0bpi1 Same exact gears...

Ray

 

[Eddyde]

LOL: I don't normally give professional advice on public websites. My PE insurance underwriter doesn't appreciate it. For you Eddy, I'll break my own rule.

Here you go: McMaster-Carr https://www.mcmaster.com/#miter-gears/=1d0bpi1 Same exact gears...

Ray

What fun is that, LOL.

 

[benmychree]

All,

Enclosed is the PDF of "Practical Treatise on Gearing" that has been mentioned in the preceding posts. It is indeed a good read, very short of about 130 pages discounting the appendices of trig constants etc. I just finished reading the sections on spur and miter gears. The beginning parts of the book pertaining to spur and miter gears, appear to be similar in nature to the abbreviated/simplified content written here.

I believe in my write-up of spur gears, or perhaps somewhere earlier in this thread, it was mentioned there are many techniques and standards which may be used to modify the shape of a basic, involute gear. The paper "Practical Treatise on Gearing" appears to go into some of the early methods being considered on how to improve the shape of a gear tooth. Be apprised, the book has publish dates ranging from 1886 to 1911 and thus, the final version was written long before the SAE (and later AGMA) finalized the standards on gear tooth shape. In that timeframe for example, Whitworth threads (introduced in 1844 and ending about 1955) were still in use. I would be hesitant to recommend "Practical Treatise on Gearing" to learn about the now-advisable ways of modifying gear teeth. -And to be perfectly honest, I am not conversant on the latest developments there. I am a member of the IEEE and ASME -but there is only so many hours in the day to keep up on things.

To clarify once again, the techniques I conveyed in my thread were about basic miter gear geometry with a basic involute tooth surface. It makes a technically correct and perfectly functional gear for low speed use -much the same quality and efficiency as the change gears on your manual lathe.

Finally, my hat goes off to all the engineers of over a century ago, who sweat their brains out figuring this stuff out. I also respect the folks who toiled behind machinery trying to actually make the darn things.

Regards

Ray

My copy of "Practical Treatise on Gearing" is dated 1920, and my Copy of "Practical Treatise on Milling and Milling Machines" from my apprenticeship days, dated 1963 ( $ 1.25 paper cover, $1.75 cloth cover), lists other publications by Brown & Sharpe, including the Practical Treatise on Gearing as still being published at that time "Contains tables and illustrations, and is written for those who wish to obtain practical explanations and descriptions for making gears". The price at that time is $1.25 for paper cover and $1.75 for cloth cover. Also listed is "Formulas in Gearing" a supplement to "Practical Treatise", cloth $1.75. I have not seen a up to date copy of either of the two to know if they were updated or not in the later editions.

 

[rdean]

I made a set of gears using your write up and even though they did not turn out as well as yours they will be just fine. I have tried several different ways of making them over the years and these are the best yet.



Thanks
Ray

 

[Lo-Fi]

An old thread, but a great write up. If you're still around these parts, thanks Ray! I'll be trying this and the parallel tooth method some point soon.