What is Needed for Making a Gear?

There are several comments pointing you in the right direction. The first step I would take is to determine the pitch of the gears on a machines at your disposal. For example, I know the 9X19 (Horrible Fright?) lathe of yours is a Modulus 1 by 20 deg pressure angle. 20 degree teeth is more common in the U S than you think. The Modulus 1 would be 25.4 DP, for what that's worth. I have an Atlas built lathe that has 16 DP 14-1/2 degree pressure angle gears. That, along with 14DP and 28DP is a common size for older U S built machines. The Atlas milling machine uses 28 DP gears. In any case, find the pitch for a machine you have and build to that to start.

Involute gear cutters cost big bux. Period. I have a set out of China where the entire set cost less than a single U S made cutter. They may not be usable for steel, but work OK for aluminium and plastic. I'm sure they would do for learning and practising. A full set is recommended unless you are aiming for a specific gear. The cutters are limited to the number of teeth they can cut. The shape of the tooth varies as the number of teeth increase. An involute gear cutter is sized to be a perfect match for one size. It then fits more or less for the rest of its' range. At the small end, a cutter only cuts a half dozen or so pitches. Toward the high end, this does open up quite a bit. The bottom line is that a full set (8 cutters) is desirable. The Chinese set I have cost less than $60. But that was a while back, I can't speak for now.

As far as a rotary device is concerned, an indexing head would be ideal. Almost as good would be a rotary table, except when you run into odd fractional angles. But a rotary device of some sort that can be locked will be vital. I watched an interesting uTube video where the builder used a CAD program to lay out the appropriate hole pattern on paper, then glued the paper to a gear blank before machining. He then used a drill to remove a good portion of metal and the lined up an involute cutter by eye. He had built a spindle to the suitable size for what he was building that was locked by a couple of bolts. Crude but doable. . . My first thought was a pin that could be used to index from the drilled holes. But he was working under primitive conditions and made a gear that meshed all the way around. He did elegant work with primitive tooling. It can be done, just taking a little lot longer.

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The dividing head PM sells is decent for the price.

https://www.precisionmatthews.com/p...e-acc/workholding-machine-acc/dividing-heads/

Probably the same one that you can get cheaper from eBay, but with better packing and follow up care. Some people have received the eBay ones in a plain cardboard box with the expected shipping damage. PM ships theirs in an appropriately reinforced carton.

I really wanted to go with a vintage US dividing head, but after looking for about a year I couldn't find anything but a serious project at anything close to the price. As with many Chinese made tools, you will want to tear it down, clean and adjust but they are surprisingly well made. There have been many posts here on the eBay and PM dividing heads. Your Wells should be big enough to let you use the fancier BS-2 universal if you want to splurge. The universal type can sync with the power feed allowing coordinated movement, kind of like how threading works on a lathe.
 
Bi11Hudson said:
There are several comments pointing you in the right direction. The first step I would take is to determine the pitch of the gears on a machines at your disposal. For example, I know the 9X19 (Horrible Fright?) lathe of yours is a Modulus 1 by 20 deg pressure angle. 20 degree teeth is more common in the U S than you think. The Modulus 1 would be 25.4 DP, for what that's worth. I have an Atlas built lathe that has 16 DP 14-1/2 degree pressure angle gears. That, along with 14DP and 28DP is a common size for older U S built machines. The Atlas milling machine uses 28 DP gears. In any case, find the pitch for a machine you have and build to that to start.

Involute gear cutters cost big bux. Period. I have a set out of China where the entire set cost less than a single U S made cutter. They may not be usable for steel, but work OK for aluminium and plastic. I'm sure they would do for learning and practising. A full set is recommended unless you are aiming for a specific gear. The cutters are limited to the number of teeth they can cut. The shape of the tooth varies as the number of teeth increase. An involute gear cutter is sized to be a perfect match for one size. It then fits more or less for the rest of its' range. At the small end, a cutter only cuts a half dozen or so pitches. Toward the high end, this does open up quite a bit. The bottom line is that a full set (8 cutters) is desirable. The Chinese set I have cost less than $60. But that was a while back, I can't speak for now.

As far as a rotary device is concerned, an indexing head would be ideal. Almost as good would be a rotary table, except when you run into odd fractional angles. But a rotary device of some sort that can be locked will be vital. I watched an interesting uTube video where the builder used a CAD program to lay out the appropriate hole pattern on paper, then glued the paper to a gear blank before machining. He then used a drill to remove a good portion of metal and the lined up an involute cutter by eye. He had built a spindle to the suitable size for what he was building that was locked by a couple of bolts. Crude but doable. . . My first thought was a pin that could be used to index from the drilled holes. But he was working under primitive conditions and made a gear that meshed all the way around. He did elegant work with primitive tooling. It can be done, just taking a little lot longer.

.
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Aaron_W said:
The dividing head PM sells is decent for the price.

https://www.precisionmatthews.com/p...e-acc/workholding-machine-acc/dividing-heads/

Probably the same one that you can get cheaper from eBay, but with better packing and follow up care. Some people have received the eBay ones in a plain cardboard box with the expected shipping damage. PM ships theirs in an appropriately reinforced carton.

I really wanted to go with a vintage US dividing head, but after looking for about a year I couldn't find anything but a serious project at anything close to the price. As with many Chinese made tools, you will want to tear it down, clean and adjust but they are surprisingly well made. There have been many posts here on the eBay and PM dividing heads. Your Wells should be big enough to let you use the fancier BS-2 universal if you want to splurge. The universal type can sync with the power feed allowing coordinated movement, kind of like how threading works on a lathe.
Click to expand...

@Bi11Hudson - Ohhh, no kidding... first place I checked was McMaster-Carr - Cutting Tools - shocking o_O
So on to other sources. eBay, the set, lowest I could find, is still around 63.00 shipped with tax included - 8pcs HSS M1 Diameter 22mm PA20° 20 Degree #1-8 Involute Gear Cutters Set

I need the R8 Shank Arbor... another 63.00

@Aaron_W - I would also like to have a dividing indexable head... I just do not know enough to decide between BS-0 or BS-1??? No way I want to spend the $$ that a BS-2 goes for...

If a BS-0 is enough, then I don't see the need to go any higher, cost wise... but again, I do not know enough to make a decision between BS-0 and BS-1... Any comments on this would be welcomed.
 
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I made a low cost setup with a junk gear used on the other end of the spindle for indexing. The catch is that you can only do gears with the same number of teeth (or an evenly dividing number). I bought a box of lathe gears which had a huge assortment. Unfortunately (or fortunately) the box had all the South Bend lathe gears I needed so I haven't been doing much cutting. It also had a bunch of gears for other lathes. I can probably sell these if I can figure out where they go to.
 
wachuko said:
@Bi11Hudson - Ohhh, no kidding... first place I checked was McMaster-Carr - Cutting Tools - shocking o_O
So on to other sources. eBay, the set, lowest I could find, is still around 63.00 shipped with tax included - 8pcs HSS M1 Diameter 22mm PA20° 20 Degree #1-8 Involute Gear Cutters Set

I need the R8 Shank Arbor... another 63.00

@Aaron_W - I would also like to have a dividing indexable head... I just do not know enough to decide between BS-0 or BS-1??? No way I want to spend the $$ that a BS-2 goes for...

If a BS-0 is enough, then I don't see the need to go any higher, cost wise... but again, I do not know enough to make a decision between BS-0 and BS-1... Any comments on this would be welcomed.
Click to expand...

Difference between BS-0 and BS-1 is simply the size. BS-1 is a little larger so it can use a 6" chuck instead of the 5" chuck on the BS-0. BS-2 is significantly more expensive partly because it is larger (mounts an 8" chuck) but mostly it is more complex, and able to cut spirals, helical gears etc.

A universal dividing head is useful if you want to make worm drive or helical cut gears rather that just straight cut. I don't know that it is the only way (usually many ways to do something) but that seems to be the main advantage.

Going back to your older post about value of small horizontal mills, gears are one of the things that they are better set up for than a vertical mill, but as Jeff shows above it can be done on a vertical mill, just a matter of using the right tooling and set up. On a large vertical mill like your Wells or Jeff's Sharp really not an issue, but on a smaller vertical mill the set up eats up a lot of your limited space.
 
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