How hard is it to make an indexer

[gtxkid]

I need to make one to drill 12 hole's around the outside of a pipe.
Were to get a servo motor and controller.
I have a 8 inch vertical indexer i want to take the handle off of and put a pulley on it.
Something i need to do because price is way to high to buy one.

[pete]

Gtx,
You could do it old school style. Take a strip of paper, wrap it around the pipe till it over laps. Then make one cut across it with a sharp blade. That's your exact length of the circumference. Stretch out a tape measure and then angle that strip of paper using various angles above or below the tape measure till you can line it up and use the tape measure to make 12 equally spaced marks on the paper. Obviously where the paper joins on the pipe is one mark. Then Refasten around the pipe and use the marks to drill the holes. If you need tighter than maybe .125 for accuracy? Then better methods will be needed.

Pete

[scmods]

GTX

There's an even easier way in this case if extreme accuracy is not an issue. Get a paper strip (not too thick) that goes around the pipe as was previously suggested. tape it to the pipe and overlap as it comes around and tape to itself. Cut it off with the sharp blade going through both layers of paper without trying to line up to an end of the strip. Fold this strip into thirds and crease well, Then fold it in half twice more, creasing well. When streached out, there will be 11 creases with about .012 max variation (location 0 and 12 are the ends). Re-tape the strip to the pipe an appropriate distance from the end and lay out the longitudinal axis across the creases (the circumfrential axis), center punch on the anvil horn and drill away.

Unless your vertical indexer has a crank to head ratio directly divisible by 12, its not going to be much help without dividing plates, etc.
Bill Walck

[stevec]

Pete & Bill, Congratulations on determining what the OP was asking (if in fact you did). I , for one, didn't understand "Were to get a servo motor and controller." ? or "I have a 8 inch vertical indexer i want to take the handle off of and put a pulley on it." ??
"Something i need to do because price is way to high to buy one." ???
If he has one why would he need to buy one.
I suspect I don't understand the need to dril 12 "hole's" around the outside of a pipe, let alone the rest of the post.
I'll be watching to see if anyone can clarify things for me.

[gtxkid]

Sorry
To clarifi
I want to make 100 rings at a time.
The owner of a shop has Hass Mills and lathe's.
He does not want to spend 12 to 15 grand to make my little rings.
He showed me an indexer he has and said that if i can find a way to put a motor on it and a elect. control to turn it.
Then he could tap into the hass and use like the coolant on to triger it.
He could put it in the G code to time out and triger turning it.
The rings are 2" ID and 2.5" OD and are .340 wide.
A ring with hole's from the outside to the inside.

I really like what you guys suggest because now i know how to apply that to other jobs.

[spro]

I don't think you've seen the end of this. There are so many involved with step controllers and then speculating what ratio that head has to the handwheel pulley.I have found myself unable to converse sometimes because ther are many ways. If is 40:1 there could be a burst of power to drive it 3.33 to where it could be indexed and locked but that is probably not what you want.

[gcarsen]

One wild and crazy way, I know one guy here in town who is a tightwad! he has a job he runs on his cnc mills. he went through the same thing. he found a rotary table, drilled a hole in the handle wheel. he sets it all up, and using the cnc control puts a dowel pin in the tool holder. programs the spindle to go over, drop down into the hole in the handle and crank how ever many rotations and partial rotations he needs to the next step. goes back to machining, and then back to turning the knob with the dowel in the spindle. it would take a bit of head scratching the first time, but it might be a look at. he just lets the machine play human cranking the handle!
Grant

[pete]

Well, I can't help with that. Out of my experience level completely. But somebody here should be able to help.

Pete

[tetramachine]

One choice, forget the servo control. Take the indexer mount it to a angle plate so its horz. to the width of .340 add the width of the parting tool, Drill ten holes with g code in a string, you rotate the indexer to next position, drill holes until complete, then part off the rings. The job will be done before you have a list of material to look for to make a electronic indexer.

[GlennW]

Use a DivisionMaster on a small horizontal Rotery Table.

http://divisionmaster.co.uk/divisionmaster.html

Then do the job on your mill.