Low budget rapid indexer project

[johnnyc14]

I've been considering buying an indexer to use when milling some of the tools I've been making. It's a pain in the butt to mill a hexagaon with just a vise. I'm new to machining and don't have too many accessories yet and the budget to buy new stuff is pretty thin. I decided to try and build one using parts I had around already. I bought a used 5" chuck at a garage sale along with a Starrett Last Word indicator for the bargain price of $50 for both. I already had a good 12" brake rotor and hub and bearing assembly that was supposed to be for a buddies Impala but he sold it before I could get the new parts installed. He didn't want the parts back so they got used for this project.






I chucked the rotor in the lathe and opened up the center to fit the back side of the bearing/hub. The plan is to use the rotor as a base for the bearing/hub. After the center hole in the rotor was bored to size I marked and drilled holes in the face of the rotor to fit the 3 hole bolt pattern on the hub.













I mounted the hub on the rotor and locked it with a through bolt to prevent the hub from turning while I milled off the flange. I made three 8mm pointed studs from some old set screws and threaded them into the mounting holes on the back of the chuck. I set the chuck on the hub and used a dial indicator to carefully first level it then center it on the hub. Then I marked and drilled the 3 holes in the face of the hub to mount the chuck to it. I drilled the holes a little over 8mm to allow adjustment for final centering of the chuck. I found a PDF image on the net for a degree wheel and resized it to 5.6" diameter to fit the flange of the hub, then I laminated it in plastic at work. I punched holes in the degree wheel to match the mounting holes for the chuck. After I got the chuck mounted and centered within .001"

 

[johnnyc14]

I needed a way to lock the hub in place so I came up with a plan for 3 brass tipped thumb screws to grab the outside of the hub. I used some 3/4" bar stock I had and some old 14mm flywheel bolts for a diesel engine. I drilled and tapped 3 pieces of the bar stock to 7/16" NC thread and then turned 3 pieces of brass from an old punch. I milled a pocket at the end of each screw hole to accept the brass peice.





I knurled the heads of the 14mm bolts and then turned the shafts down to size for the 7/16" thread. This was my first kick at single point threading and I screwed up the first bolt but luckily I had a spare and the other 3 went well. Then I cut them to lenght.












Then I welded the threaded block to amll brackets to be bolted to the hub

 

[johnnyc14]

The last phase was to mill the rotor to a 9.25" square so it fits on my mill table which is only 9.5" wide. I milled one side at a time and used my new indicator to square it up on the table after each side was done.











The socket in the last picture is not my work, it's just there for show. I haven't used the thing yet but hopefully I'll get the time this weekend.

 

[Ken_Shea]

johnnyC14
That is great job of thinking outside the box, I like it.
That job is relatively involved with a number of operations, doing it over, what would you have done differently?

Thanks for posting.

Ken

 

[pineyfolks]

Looks good. Is there a pointer for the degree wheel or is the plate under the chuck going to be drilled for a pin in common degree spaces?

 

[rgray]

I like it!!!
Been rackin my brain trying to figure out a use for bake rotors.

Interested to know if it is ridgid enough on that wheel bearing.
The wheel bearing is made to be held tightly together by the axle. Axle nut torque is usualy around 150-200 ft lbs. I know they don't feel the least bit sloppy with no axle through them but if it lacks ridgidity then that may be a way to gain some(through bolting and tenssioning the wheel bearing).

 

[mitsue]

Well done John. The chuck and indicator are a good garage sale gloat by themselves. Nice work on the rotary table. I'm a little conerned how well the brass will hold the table from rotating under cutting loads. Brass has a high lead content and is slippery at the worst times. I really like using the hub and rotor. You could chuck up the backing plate, lock into the lowest gear and use a tool tip to cut a series of shallow grooves along the Z axis, (like a straight knurle) for the brass to bite into.

If you have time, drop by for a beer, (don't bring any as I have a gross excess at the moment) and look at how the locks on my rotary tables work.
I recently had about 75 pounds of MT2, MT3, and MT4 drills left on my door step so I have some spares for you. Fall cleanup here so you can have one of everything I have three of, including cutting tools, rotary tables, mill vices etc.
Darcy

PS Any other local members are welcome to contact me by email and drop by also.

The pics are of the garage/shop I have been building all summer for a friend.

 

[johnnyc14]

Thanks guys,

Ken, I haven't used it yet so I'm not sure how rigid it will be and I may have to change the set screw arrangement.

Bill, I have not installed a pointer yet. I'm going to see how it works and your suggestion to drill the hub flange for common angles would work well with pointed set screws.

Russ, I thought of that and I'll see if the press fit holds it well enough. If not I'll mill a recess in the top of the flange splines to allow a through bolt arrangement to keep it tight. It might be tough to do as the splines are hardened.

Darcy, good point about the brass. That shop is looking great, I wish I had that much room. I'll text you tomorrow and see if you're in the shop so I can stop by and take you up on your offer!!:LOL: We've got the whole clan (17 people) coming for Thanksgiving dinner so today I'm playing chef. I've come down with shingles so I'm not moving too fast the last few days. My back and chest feel like I've got the worst sunburn I ever had.

Cheers,

John