[How-To] Rank beginner question on cutting gears

Gear calculations are tabled in the Machinery's Handbook, in your case in the metric section. There also are a couple of good videos by "This Old Tony" on the subject. There are many others, I happen to like ToT for his "half bubble off plumb" sense of humor.

The basic calculations are as follows:
OD(Outside Diameter) = number of teeth + 2 X the modulus. ie. for a M1_24 tooth gear ~ 26 X 1 in mm
DoC(Depth of Cut) = 2.25 X module ie. 2.25 X 1 mm

This is a ballpark figure, the fit and tolerance may well need adjusting depending on usage of the gear. Those adjustments are in Machinery's Handbook.

Now, to dogs: There are times I use "store bought'n" dogs, other times I use a ground rod clamp. For small (well, large for me) work, it's a good fit on 5/8 rod. The screw will get smashed up some, but not where it counts. I also use cable clamps and the like. But I have a good supply of electrical parts. . . In all probability, you will want to do finished work between centers.

However, a chuck should have been included with the indexing head. Transferring the work from the lathe to the indexer chuck is just a matter of indicating to your specs. It might be a piece of shimstock in one jaw or maybe getting a 3 or 4 inch 4 jaw if things are really important.

An important consideration is true horizontal (90 Deg) of your head. You don't need a surface plate, a milling machine table will do fine. Your lathe ways are probably too small. Measure the height, indicate, close to the chuck, and then at the end of the rod. A foot or more is preferable, if you have space. When the two readings are the same, set the pointer for 0*. Or 90*, whichever is appropriate. You probably can trust the degree tics, the pointer is the problem most times. Once the divider is trued, set the tailstock to match.

It's a long story behind the flanges where we won't go. The bottom line is table saw blade flanges are available in 1/2, 5/8, and 3/4 sizes. I use the 1/2 inch ones regularly. Thread half the mandrel to 5/8 fine, screw on a hardware store nut til it's there to stay. Then turn the mandrel to 1/2 inch facing the 5/8 nut as you go. Thread the mandrel 1/2-20 and the only facing then is the 1/2 nut. The saw flanges aren't really "machine shop" quality, but are quite easy to make and learn on. Or easy and cheap to find. . . And a 127 tooth 4 inch dia gear with 12mm bore isn't really that stable without them.

The cutting boards I've seen at Wally World were 1/2 inch, more likely 12mm. I have a sheet of 5/8 plastic salvaged from a pizza joint that I work from. Whenever I can stop Wife from stealing a chunk. . . I suppose 8mm (likely) stock would work well enough for light gears but would be a bear to work. Too thin for change gears, for sure.

In the long term, tooling will cost as much, or more than the machines. Any tooling you can make cuts that cost down significantly. I have an Atlas shaper, an Atlas (benchtop) milling machine and an Atlas (Craftsman) lathe. And several grinders and drill presses. Being the cheap old buzzard I am, I waited 'til I found the machines at a price I was willing to pay. Took several years to acquire them all. But tooling is a different issue. Until I retired time was precious, so I bought tooling as I needed it. Usually at full retail. . . Now that I'm retired, I had one stroke too many and now am confined to a wheelchair. Ce'st la vie, stuff happens. Go it while you can.

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@Bi11Hudson, thanks for sharing your knowledge and tips. They are appreciated.

Painfully aware of the march of time. Trying to get in some quality time at this before it gets too difficult. Hope to be at least be a passable hack machinist in a few (5-10?) years, if the good Lord grants me reasonable health that long. Or at least reduce my scrap rate!
 
Right up front, you must STOP counting the hours, weeks, months, years, ad infinitum 'til you are a "machinist". This is a hobby, time as such doesn't count, experience does. I bought my first machine (a UniMat DB-200) in 1969. Yet I am not a machinist after all these years. I am an electrician and electrical engineer. I have piddled with electricity since grade school. My hobby is model (electric) trains. Also since childhood.

When I wanted to do something, I figured out a way, or looked in an old book, to find a way to do it. Need, necessity, thirst for knowledge is what drove me to learn the basics of machine work. I am not a "machinist", perhaps a "second year apprentice" at best. In a busy week, my machines might run for days on end. And then sit idle for weeks, or months while I pursue the end result of the machinist work. I need a tool that isn't available anywhere, I build it after looking in all the dark corners I can find.

Just as with machine work, I am a pretty fair carpenter. But by no means a journeyman. I am an electrician of the old school, probably a master by todays measure. I actually held a Master's ticket in Florida in 1974. Grandfathered in. . . Never pursued it, it wasn't where I wanted to go. Just a way to make some money for a while. Add to that the automobile mechanic, again old school, rigging learned when I went to sea, hoist and crane operation from working on them at sea and in heavy industry, casting from working in a foundry and some aluminium homemade parts, ad infinitum, ad nausium. Bottom line, I am not a machinist, never have been, likely never will be.

In your case, you must ask yourself what drove you to do machine work. In particular making gears? Do you desire the knowledge of how gears are made? Or have you a project that requires special, or custom, or cheap(?) gears. Follow that original drive, whatever it is.

If machine work is the desired end result, then follow an old school apprenticeship path. If you are building a contraption, build your contraption, following where ever it leads you. Machinist, electrical, carpentry, even fibre optics (which I have done for a while) or computer programming.

This is a hobby. Any hobby is a pursuit to chew up time and learn what you want to learn because you want to learn it. No other reason. What information I want to pass along is strictly because I want to pass along information. I never attended high school, following my father who never went to formal grammar school. In no wise would I be allowed to teach in a formal school, I smoke tobacco. Politics would keep me out of a classroom on that alone. I just want to help people. If I know something useful, that knowledge demands to be passed along.

I apologize, it seems I am preaching now. So I'll leave room for someone more knowledgable. End of sermon. . .

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Was only a figure of speech. There's an old saw that it takes 10000 hours of practice to be considered expert or good at things. It's mostly true. Now that's actually practicing the art, not standing around with your hands in your pockets.

I'm under no illusion that after some time interval is up I'll be an expert. I only brought it up that it takes a long time to master things. And it takes time on machine to do it. Peace Bill. Not expecting magic. As you said, it takes diligence and practice, practice, practice. If I didn't want to get better at this, I wouldn't be here asking questions. I do want to improve and learn more. There's loads of things I'd like to try to make or improve. I'm stumbling over some basics now, but those problems will be in the past some day. Then I'll be able to tackle harder things. Bit by bit, slowly improving. Anyways, that's the plan.
 
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Right on Hudson!
@ 78 I've got less time remaining than $ but I'm still on the cheap side. I've been scraped off the floor several times, unconscious, low blood sugar. My hobby can better be described as "taking things apart to see how they work" than anything else.
I fix things, stuff that couldn't be economically justified, but just to see if I can. It's the challenge, the process.
As a kid I always wanted an HO train, never got one. While I was in Germany, years ago I bought some N gage. Now it is obsolete. Not computerized.
Above all have fun doing what you enjoy.
 
My perception of an "expert" is that when reduced to the component sounds of "Ex" and "Spert", being a "has been" and a "drip under pressure", an expert is usually an expert in his own mind. If you want to become an "expert", more power to you. I will assist with the basics where I can. I didn't intend to get you fired up, I figured the time involved was a figure of speech. My intent was to get you to relax. I can't relate to the machinist trade like I can electrical. In my field, 10K hours for a house wireman will make him a Master House Wireman. But hand him an elementary for relay logic and he becomes a second year apprentice.

My intent, again, is to get you to relax and enjoy the hobby. Follow whatever idea crosses your mind and before you know it, people will come to you for answers. To me, that is what makes a Master, not so many hours of study. Not passing a state exam. My opinion of "state examiners" is lower than that of experts, any way. They are on a power trip and can barely pronounce the technical words, never mind what they mean.

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Message read loud and clear. I just want to make some stuff and not flub up too bad. I do know it will take a while to be decent at some of this. It is a hobby for me, but I do want to make some things with a moderate degree of precision. Not because it is actually required right now, but because I'd like to do it a little better each time. Then when the precision is really required, I'd have some of the skills needed.

I'm not interested in impressing anyone with what I make. It doesn't motivate me. What does motivate me is to be able to make things that interest me, be they automotive related, or making fixtures, tools, little gizmos that tickle my fancy, or household items that never seem to come in the size that I need. I enjoy it when things are assembled together and they work. It's the act of creation that lights the fire. And seeing it through from idea to completion. That's what keeps me motivated. I want to do more, but to do that I need to develop additional skills.

Probably ought to mosey back on topic...
 
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