So, I need a gear....
Since I have three blanks I may just cut to full depth. This, as yours was, is more of a learning exercise than anything, so I'm not as concerned with the actual gear as I am the "process".
I wanted to check the pitch diameter whichwever method I used and could not find module pitch wires anywhere, so I bought drill blanks that were close and honed them to size with my "key chain" size external hone. It worked really well. More fun that way too!
They should work just fine for this project.
The other reason for taking the time for this project is that I will now be able to hopefully make a couple of gears to enable a couple of the thread pitches I don't presently have available such as 27 and 11.5 tpi.
Thanks for the input Jim!
I wanted to check the pitch diameter whichwever method I used and could not find module pitch wires anywhere, so I bought drill blanks that were close and honed them to size with my "key chain" size external hone. It worked really well. More fun that way too!
They should work just fine for this project.
The other reason for taking the time for this project is that I will now be able to hopefully make a couple of gears to enable a couple of the thread pitches I don't presently have available such as 27 and 11.5 tpi.
Thanks for the input Jim!
Glenn
Operating machines is perfectly safe......until you forget how dangerous it really is!
Operating machines is perfectly safe......until you forget how dangerous it really is!
Set up and ready to start...
I set the cutter height with gage blocks. Measured the cutter thickness, divided by two, and subtracted that from the center height of the Dividing Head. Wrung up a stack of gage blocks, set them on the table just below the cutter, and brought the knee up to just touch the lower surface of the cutter with the gage blocks.
Half way around and working just fine.
Right after the half way point I decided to drizzle a little coolant on the cutter to see what happens. I believe Iron should be cut dry, but the cutter seemed to like it as it seemed quieter and the finish improved a little bit.
Made it back around and when I re-cut the "0" index tooth you could just hear the cutter touch it. I've got 50 full teeth and two blanks!
I checked the pitch diameter with my wires and got 3.0957" out of a perfect 3.0962". Looks like the "single cut" method works just fine, as did the new little dividing head!
I can see where a horizontal mill is the right tool for the job though.
It certainly was an interresting project as I learned a lot about spur gears and dividing heads.
Sorry this thing got drug out so long, just not enough "play time" lately, but it's great to be busy at my real job!
I set the cutter height with gage blocks. Measured the cutter thickness, divided by two, and subtracted that from the center height of the Dividing Head. Wrung up a stack of gage blocks, set them on the table just below the cutter, and brought the knee up to just touch the lower surface of the cutter with the gage blocks.
Half way around and working just fine.
Right after the half way point I decided to drizzle a little coolant on the cutter to see what happens. I believe Iron should be cut dry, but the cutter seemed to like it as it seemed quieter and the finish improved a little bit.
Made it back around and when I re-cut the "0" index tooth you could just hear the cutter touch it. I've got 50 full teeth and two blanks!
I checked the pitch diameter with my wires and got 3.0957" out of a perfect 3.0962". Looks like the "single cut" method works just fine, as did the new little dividing head!
I can see where a horizontal mill is the right tool for the job though.
It certainly was an interresting project as I learned a lot about spur gears and dividing heads.
Sorry this thing got drug out so long, just not enough "play time" lately, but it's great to be busy at my real job!
Glenn
Operating machines is perfectly safe......until you forget how dangerous it really is!
Operating machines is perfectly safe......until you forget how dangerous it really is!
- seal killer
- Posts: 4696
- Joined: Sat Aug 18, 2007 10:58 pm
- Location: Ozark Mountains
Sweet job. Those tapered set mandrels actually have a pretty darn good
grip. The only trouble of course is if it does happen to slip, it would be
tough to get back to the same spot.
In my case, the gear was driven by a woodruff key, so it had to have
an internal keyway, something I knew would have to be done somehow
no matter what, so I did that first before cutting the teeth - using the
lathe as a shaper.
So it was a natural to make the arbor that held the gear a keyway on
it as well, and then as long as the arbor was held tight in the 5C collet
there's no way it could slip.
That dividing head, it looks to be a near copy of a brown and sharp one.
Jim
grip. The only trouble of course is if it does happen to slip, it would be
tough to get back to the same spot.
In my case, the gear was driven by a woodruff key, so it had to have
an internal keyway, something I knew would have to be done somehow
no matter what, so I did that first before cutting the teeth - using the
lathe as a shaper.
So it was a natural to make the arbor that held the gear a keyway on
it as well, and then as long as the arbor was held tight in the 5C collet
there's no way it could slip.
That dividing head, it looks to be a near copy of a brown and sharp one.
Jim
I found out the difference between a mandrel and an arbor when I went to remove the gear. I had to use a 3 ton arbor press to break it loose, so....!
The large end is near 1 1/8" dia., so it is a little stouter than it looks in the pics. It is also a K.O. Lee mandrel and it makes a BIG difference. If you are familiar with expanding mandrels, the mandrels that K.O. Lee made have easily twice as many serrations on the sleeve as any others I have seen. This makes them VERY conforming to the bore and the tapered surface throughout it's grip range and gives then much better gripping power. I checked it between centers with a DTI on the gear blank OD before I put it in the dividing head and it had .0003" TIR. Their mandrels are pretty true too!
The large end is near 1 1/8" dia., so it is a little stouter than it looks in the pics. It is also a K.O. Lee mandrel and it makes a BIG difference. If you are familiar with expanding mandrels, the mandrels that K.O. Lee made have easily twice as many serrations on the sleeve as any others I have seen. This makes them VERY conforming to the bore and the tapered surface throughout it's grip range and gives then much better gripping power. I checked it between centers with a DTI on the gear blank OD before I put it in the dividing head and it had .0003" TIR. Their mandrels are pretty true too!
Glenn
Operating machines is perfectly safe......until you forget how dangerous it really is!
Operating machines is perfectly safe......until you forget how dangerous it really is!
-
- Posts: 3803
- Joined: Wed Feb 21, 2007 9:21 pm
- Location: Vallejo California
I am turning greener and greener !!
Boy, if I've ever felt like a wanna-be, this is one of those times !
You make it look like just seating down and having breakfast!
Glenn, where did you find that hand-held honing tool?
I've never seeing one like it. Mind posting some close-ups and different views?
May make me some.
Boy, if I've ever felt like a wanna-be, this is one of those times !
You make it look like just seating down and having breakfast!
Glenn, where did you find that hand-held honing tool?
I've never seeing one like it. Mind posting some close-ups and different views?
May make me some.
There are no problems, only solutions.
--------------
Retired journeyman machinist and 3D CAD mechanical designer - hobbyist - grandpa
--------------
Retired journeyman machinist and 3D CAD mechanical designer - hobbyist - grandpa
- seal killer
- Posts: 4696
- Joined: Sat Aug 18, 2007 10:58 pm
- Location: Ozark Mountains
Glenn--
You have really enthused me!
IF I needed a gear, THEN I could buy one of those spin indexer thingys and the dividing stuff.
I probably need a gear. My wife always says I am missing one.
--seal killer
ps And gage blocks. What grade are yours? What grade would be "good enough" for your gear project? Were the gage blocks absolutely necessary or could you have managed without them?
You have really enthused me!
IF I needed a gear, THEN I could buy one of those spin indexer thingys and the dividing stuff.
I probably need a gear. My wife always says I am missing one.
--seal killer
ps And gage blocks. What grade are yours? What grade would be "good enough" for your gear project? Were the gage blocks absolutely necessary or could you have managed without them?
You are what you write.