An attempt to execute the 400 rpm threading for a G0602 plan

[Baithog]

I almost canceled this project. Tooling was lost by the shipper, the metals order was back ordered, and then lost. I finally get the metal and find that for some unknown reason, half way through the order, I started ordering 6- 1” pieces instead of 1-6” piece. There are some days and some projects that the universe doesn’t like. My boss never let us engineers go home on days when the laws of physics were suspended, so I’m not going to start going with the flow now.

The gear blanks were a fun exercise. It would have been nice to have one of the X thingies that move the part away from the chuck face, or a smaller 4-jaw chuck to fit my 1” long pieces of metal. And a vice on the 4X6 band saw to cut short pieces with. I managed the saw issue by clamping a drill press vice in the saw, then clamping the round stock in it. I cut about 80% of the way through, put a wedge in the kerf, then turned the stock over and finished the cut. A small stock holder is on the list now. I hate to throw away itty bitty pieces of material.


So after slicing, dicing, and turning, I end up with this -


Notice the stacks of 1” stock in the background. The stub mandrel with the cutter mounted turned out to be concentric challenged. Not being able to power feed away from the headstock has me turning parts around that I really shouldn’t. This project will fix the missing tumbler, too. Being able to turn between centers is also on my list, so at some point I will fabricate a family of lathe dogs. The one I bought for this project needs extensive modification to fit my drive plate. The teeth on the #6 cutter are more worn on one side than the other. Hopefully the slightly deeper cut will not screw up the mesh.

So a trip through this set up and I have gear teeth.


Yes, that is a horizontal rotary table bolted to an angle plate standing in for a dividing head.

And now for the teeth -


The gear on the lower right is the result of setting up the mill for 30 teeth, then deciding to start with 40 tooth blanks after all. The cutter was changed, but then I got called away to dinner, then a TV show, and returning to the shop in auto pilot, I cut 40 teeth into the plastic blank. It meshes reasonably well with a module 1 gear, and the teeth are a bit pointy. That is why there is a white and a black idler gear.

Next are the axles, which will be used to test fit the sleeve bearings and the clutch.

 

[roadie33]

I so badly want a mill so I can cut gears like that.
That looks so cool to be able to cut your own gears.

I want to replace all of the Zamak ones on my lathe with steel, to hopefully cut down on the noise they make.

 

[Baithog]

A mill is really nice, no doubt about it. Steel gears will not be quieter. All metal on metal gears make noise. Cast iron is supposed to be the quietest of the metal. Plastic gears are much quieter until the tip speed gets high. Then it's sorta like off road tires on a truck.

 

[JimSchroeder]

Congratulations Baithog, your progress is admirable. What model lathe is this clutch being constructed for? I really like your mill, looks like a Bridgeport.

Jim

 

[Baithog]

Jim – I have a G0602 lathe like you do, only mine is still belt driven. No Bridgeport here. I wouldn’t turn one down, but I really don’t have the room, and they are not common on the used market here in central Florida. I have a G0759, which is the G0704 with a DRO. You posted the model of the body from the outside. Could you post the view from the machine side? I'm not sure I understand the reference to cutting the relief for the shift fork. Maybe it will make more sense when I start in on it, but my brain just isn't grasping the cavity for the clutch stack.

******************

So I set up to turn the main axle between centers, and then turned the flange and outer axle. Just for jollies I measured the output gear bore again. That was fortunate because the bore was 0.009 over size. The telescope gauge had a scratchy spot, which made the hole look smaller than it was. That made the last pass remove too much. Cheap tooling gets you sometimes. I just made the outer axle bigger and bored one dog gear bushing a little more… problem solved. After the output gear error, I lost a lot of faith in my internal measuring ability. I found a reamer for the outer axle bore. It worked really nice.




To proceed, I needed the rotary table, so I took time out to make a tooling plate for my 6-inch table. It’s not as big as Jim’s, being only 7 inches, but it has turned out to be really handy. Just today, I was making the end washer for the axle and it parted off too thick. Actually I preferred too thick to too thin. There is no way to put something that thin in a chuck, so I clamped the washer to the tooling plate and milled it to thickness.



This is a dog gear getting its dog pin hole drilled


And this is the slot being milled in the clutch disk.




The clutch is deceptively simple looking. I expected to have problems with the gear teeth, which I didn’t. The clutch is just some slots, but it took 3 tries to get the 3 slots in alignment.

And here is the assembled stack.




The bronze washer is recessed into the output gear and the outer axle shorted slightly in my version. Try as I might, I couldn’t get enough clearance on the main axle to get a thick enough washer on it… at least a washer I was comfortable with. The gears and clutch spin freely, so it should work. The last job with the stack is to fabricate the key slots. The externals are no biggy. The internals are fighting me. I’ve tried using a cutter in a boring bar as a poor man’s shaper, but it wasn’t going too well. After an hour of trying different grinds on the cutter, I opted for a broach. It should be here Saturday. I will have to make a bushing for the clutch and the output gear. I’m thinking the bushings will go a lot quicker than my cutter grinding.

 

[Uglydog]

I'm working toward gears. I hope!
Thank you for the inspiration.
Daryl
MN

 

[Baithog]

New machines sometimes come with unexpected learning opportunities. The G0759 is so much more rigid than the old Seig X2 that I sometimes forget that it is not a 2-tonner. The body provided me with one of those learning experiences. I squared the block up with the table and drilled the pilot holes with a new ½” drill. The block then moved to the rotary table to have the gear pockets milled. Having this new, powerful mill, I mounted a ½” mill and started climb milling .100X.100 cuts. All went well for most of the pocket. I had a mound of chips obscuring the pocket, then the motor stalled and the motor fuse blew. I assumed that I had just gotten carried away with the feed rate. I replaced the fuse with my one and only fuse and promptly blew it too. So after a trip to Radio Shack for a fuse, I did some investigating. The end mill was being sucked down into the pocket by the down force of the flutes. I put a strap wrench on the spindle and tightened the collet as much as I could with the little 6mm wrench. It was still pulled down. Success only came by using an aluminum, two flute end mill (slower twist), reduced cut to .05X.1, and conventional milling at a reduced feed rate. I think I need those end mill holders after all. The bottoms of the two idler gear pockets look like a contour map of the great mound, but the body is functional. If this gadget works like it’s supposed to, I’ll order another block of aluminum and make it prettier.

This is the body from the outside with the main and input axles mounted. The butchery is on the other side.

 

[Baithog]

And here is the other side with all of the gears mounted. Everything turns freely, but is a little noisy. I think the input idler is a smidge too close to the forward dog gear. I temporarily mounted the body on my G0602 so that it could drive the input idler. Other than a bit more noise than I expected, everything seemed to be spinning.

 

[6literZ]

Looking good! Definitely on my to do list!

 

[jar944]

So a trip through this set up and I have gear teeth.

View attachment 94832
Yes, that is a horizontal rotary table bolted to an angle plate standing in for a dividing head.

I wondered if that would work, I happy to see that it does. I'm going to have to order a larger angle plate now.

Did you use a index plate on the rotary table, it doesn't appear so from the pictures?