Group Project: Dividing Head - The Build

[rwm]

I think he has 5/16 but more $. Could we use 1/4" if a target thickness of .230 was acceptable? And it would probably be 4.950" diameter.
R

 

[Ianagos]

I think he has 5/16 but more $. Could we use 1/4" if a target thickness of .230 was acceptable? And it would probably be 4.950" diameter.
R

If the plate is saw cut from round I highly doubt it will clean up with .010” per side. If it’s from plate maybe.

Just I have to be careful to not distort the plate while trying to hold on to it. Pretty difficult actually.

I do a lot of high tolerance work typically holding .0005” or better. You would be surprised how much stuff moves while machining and from clamping pressure.

 

[rwm]

It is laser cut from plate. I think we could go down to .200 on thickness if we had to but I don't think we will. The flatness tolerance on these parts is pretty loose.
R

 

[Shotgun]

Do they even need to be that thick? All they have to do is provide a pin hole to stop a handle from rotating until the spindle is locked. There is almost zero pressure against the side of the disk, and even .100" is overkill for the sheer strength needed to handle that. If the disk were to flex away from the pin, I doubt that there is a device that could measure the affect on the spindle rotation.

Are we solving a problem by spending money on thicker material and then holding micron tolerances on the thickness? (vs the pinhole placement. That definitely needs tight tolerances.)

 

[Ianagos]

Do they even need to be that thick? All they have to do is provide a pin hole to stop a handle from rotating until the spindle is locked. There is almost zero pressure against the side of the disk, and even .100" is overkill for the sheer strength needed to handle that. If the disk were to flex away from the pin, I doubt that there is a device that could measure the affect on the spindle rotation.

Are we solving a problem by spending money on thicker material and then holding micron tolerances on the thickness? (vs the pinhole placement. That definitely needs tight tolerances.)

Just the thinner they are the more difficult they become to
Machine in the first place

I think I found material for a decent price

 

[ErichKeane]

Do they even need to be that thick? All they have to do is provide a pin hole to stop a handle from rotating until the spindle is locked. There is almost zero pressure against the side of the disk, and even .100" is overkill for the sheer strength needed to handle that. If the disk were to flex away from the pin, I doubt that there is a device that could measure the affect on the spindle rotation.

Are we solving a problem by spending money on thicker material and then holding micron tolerances on the thickness? (vs the pinhole placement. That definitely needs tight tolerances.)

Yeah, the ones I have on my grizzly dividing head aren't nearly that thick. If I were to make these, I would probably do:

1- Hold in lathe chuck, face off and do the drilling-features in the middle.
2- Attach to an arbor centered on the center-feature made in #1. Turn the OD, face the other side.
3- Use a super-glue arbor of some sort to hold it down for drilling/marking. Alternatively, use the same center-feature to hold it down on a pallet of some sort.

 

[Janderso]

Finished a 2nd shaft today! My die might be cutting too shallow, but I can always go over them again later once I get some nuts to test it out on.

Next to it is the 3 foot-long pieces I am going to try to get 6 more of these shafts out of fortunately I think I managed to get a single ones time down to about 2 hours, so hopefully doing a pair won't be too much longer. There is a bit of extra order of operations to do, so that will likely be a challenge.

I expect my chuck for my rotary table to show today, but I'm still not quite brave enough to move onto another Op with that part.

Erich, "Making scrap at ludicrous speed"?????
Maybe years ago, it seems you know what you are doing.
Beautiful work sir!!

 

[Shotgun]

I'm very happy about this picture. Got up early to beat the 105 degree heat index, and got all the insides faced off. At first, I was trying to face them all off at the exact same thickness. Just so that they would all be consistent. Then I got to thinking that the only thing I was doing was dulling tooling and making the part weaker. So, I just faced them off to clean them up. That went MUCH faster. The next steps are to:

1) drill and tap the bottoms for the screws to attach the auxiliary base.
2) bolt the parts together, then drill and ream for the location pins
3) after making a spacer to hold the tops rigid, line bore them on the lathe.

 

[Flyinfool]

On the index plates. the only thing critical is the hole locations. OD and thickness are not critical at all. I went with that thickness because the one I had access to was that thick.. the thinner you get the harder to control it for machining.

 

[rwm]

The eBay seller got back to me and he will not give a discount since steel prices are going up. I guess Covid was a bad time to start this?! He wants $4 per disc for 1/4 x 5" plus shipping. That sounds like a lot. I have one other resource to check but no promises.
Robert

Sorry Ianagos. I did not see your comment above that you had found material. That's great!
Robert