Indexing plate vs dividing head

Suzuki4evr

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This might be a dumb question, but can you use an indexing plate to do the job of a dividing head or what is the main difference. I am asking because I do not have either of them nor have I ever used any of these. All the clever people please advise me.
 
Can't help you on this one, but I'm sure interested in the answers. I also have never used either, but there have been times when I wish I had one or the other. Just not sure which. Hopefully, we'll get an education.

Regards,
Terry
 
An indexing 'head' (you said plate-?) often called a (super) spacer, divides 360 degrees into common and equal divisions (2, 3, 4, 6, 8, 12, 16, 24 might be common). Those are the only choices you get. It will make those divisions quickly and hold them rigidly. They are often used for production work, but can certainly be used for one off jobs. You will need the masking plates to be able to avoid indexing where you do not want to go.

A dividing head is used mostly for making larger numbers of divisions on things like gears, sprockets, and such, and quite accurately. In general, the setups are not as rigid and take more time to prepare, but there are exceptions. They are fairly slow to set up, but can be relatively quick to change out parts. It is possible to set a dividing head up for just doing one interval, but I would be looking for another way to get there.

Neither of those options is very useful for laying out single odd angles, like 139 degrees. A rotary table does that job much more quickly and easily. Note that there exist rotary tables with included or optional dividing plates, which can do a lot of useful things in a home shop, but are not so great for most production work unless you are clever and make quick change work setups for swapping out parts.
 
Another useful tool is the spin indexer, AKA "spindex", which will let you quickly set angles at one degree intervals, and uses 5C collets to hold the work. The import ones are quite inexpensive and will do work accurate enough for most anything that stays in the Earth's atmosphere.

Super spacer with masking plates:
1516132701845.png

Indexing head and tail stock:
1516132806084.png

Rotary table:
1516132955046.png

Rotary table with dividing plates:
1516133039688.png

Spin indexer and tail stock:
1516132865763.png
 
Last but not least, the cheapest, quickest, and easiest tooling for quick indexing, collet blocks. They are available for R8 or ER collets, and are used by far the most in my home shop and many others as well:

1516133355133.png

In use:
1516133423070.png
 
I have seen the term indexing plate mentioned mostly with wood lathes. Many wood lathes have an integral index feature, but a fixed or limited number of locations. My wood lathe has 24 fixed index locations so 15 deg apart.

If I needed increments of e.g., 20 deg I would need to purchase an index plate like this one, which fits behind the wood lathe chuck.

This item is from Alisam Engineering.

Alisam Engineering Large Indexing Plate

1516134369365.png

A machining You Tube person, Steve Jordan, made a custom back plate with 24 holes and a pin to engage to enable using as index feature.

Steve Jordan index back plate for chuck



I would also need to purchase or make a bracket and pin. The bracket would attach to the wood lathe bed and the pin would mount on the bracket and be used to engage in a hole in the index plate.
 
Another useful tool is the spin indexer, AKA "spindex", which will let you quickly set angles at one degree intervals, and uses 5C collets to hold the work. The import ones are quite inexpensive and will do work accurate enough for most anything that stays in the Earth's atmosphere.

Super spacer with masking plates:
View attachment 254693

Indexing head and tail stock:
View attachment 254694

Rotary table:
View attachment 254696

Rotary table with dividing plates:
View attachment 254697

Spin indexer and tail stock:
View attachment 254695
Thank you Bob,you gave me alot of new information. These tools does not come cheap though. A lot of times I make plates with equal spaced holes,usually 8 holes,but I want to start making gears and shafts with splines and so on. I want to make a set of gears for my lathe so I can do other tipes of thread. What would you recommend for what I want to do and that is not to costly? Thanks for all the pics

Michael.
 
Thanks for the info, Bob.

I just recently made a round knob for a bracket I had made earlier. I made an arm for the bracket that would swing, and I needed an easy way to lock it down without having to go find a wrench every time I moved it. The knob is about 2" in diameter with a 5/16" threaded hole in the center. I produced a whole lot of aluminum shavings trying to figure out the best way to make it and finally came up with this method:

1. Mounted a piece of 1 1/2" aluminum in my 12" rotary table that had already been centered on my mill. The aluminum stock was a piece of scrap that had sufficient 'wings' which I could use to clamp onto the rotary table.
2. Drilled and tapped the 5/16" center hole.
3. Used a 1/2" course roughing end mill to mill the circle about 1/8" over the final diameter. I milled to about an 1/8" shy of going through the entire 1 1/2" stock.
4. Removed the 'wings' and chucked the part in my lathe using the threaded hole to mount onto a make-shift arbor. The rough section where the 'wings' were removed was toward the BACK of the chuck.
5. Milled a shoulder about 3/4" deep and 7/8" in diameter.
6. Went back to the rotary table and mounted and centered a 3-jaw chuck on it.
7. Mounted the part in a hex collet block with a 7/8" 5C collet; then mounted the whole contraption onto the chuck.
8. Used a finishing end mill to clean up the shoulder.
9. Now comes the fun part: mounted a 1/4" finishing end mill and moved the table in 1/8" from the shoulder.
10. Milled a 'half-hole' every 30 degrees, resulting in a 12-point 'serrated' knob. (I'm sure there's a more technical term for this, but I don't have a clue what that might be.)
11. Took the knob back to the lathe, rounded over the edge and, using the compound slide, milled a slight taper on the face of the knob.
12. Still have some sanding and polishing to do, but it turned out pretty nicely. (See the pix below.)

Now for a question: That was a lot of work!!! The entire time I was making this part, I found myself declaring there has got to be an easier way to do this. How would you go about making such a part? Which, if any, of the tools you described could have eliminated some steps and streamlined the process?

Long winded, I know, but hopefully it's understandable.

Regards,
Terry

IMG_1301.JPGIMG_1302.JPGIMG_1303.JPG
 
Thank you Bob,you gave me alot of new information. These tools does not come cheap though. A lot of times I make plates with equal spaced holes,usually 8 holes,but I want to start making gears and shafts with splines and so on. I want to make a set of gears for my lathe so I can do other tipes of thread. What would you recommend for what I want to do and that is not to costly? Thanks for all the pics

Michael.
For what you want to do, a dividing head with centers, chuck, and tail stock would be the correct tooling. There are no easy ways to get there without spending some money. I have seen a few machinists who have made their own dividing heads and indexing plates, but that is a bit over the top. If you can design your gears and splines with divisions only measured in whole degrees, then a spin indexer could do the job. Mine cost under $50 US, and collets would also be needed. You could do without a tail stock or build one.
 
Thanks for the info, Bob.

I just recently made a round knob for a bracket I had made earlier. I made an arm for the bracket that would swing, and I needed an easy way to lock it down without having to go find a wrench every time I moved it. The knob is about 2" in diameter with a 5/16" threaded hole in the center. I produced a whole lot of aluminum shavings trying to figure out the best way to make it and finally came up with this method:

1. Mounted a piece of 1 1/2" aluminum in my 12" rotary table that had already been centered on my mill. The aluminum stock was a piece of scrap that had sufficient 'wings' which I could use to clamp onto the rotary table.
2. Drilled and tapped the 5/16" center hole.
3. Used a 1/2" course roughing end mill to mill the circle about 1/8" over the final diameter. I milled to about an 1/8" shy of going through the entire 1 1/2" stock.
4. Removed the 'wings' and chucked the part in my lathe using the threaded hole to mount onto a make-shift arbor. The rough section where the 'wings' were removed was toward the BACK of the chuck.
5. Milled a shoulder about 3/4" deep and 7/8" in diameter.
6. Went back to the rotary table and mounted and centered a 3-jaw chuck on it.
7. Mounted the part in a hex collet block with a 7/8" 5C collet; then mounted the whole contraption onto the chuck.
8. Used a finishing end mill to clean up the shoulder.
9. Now comes the fun part: mounted a 1/4" finishing end mill and moved the table in 1/8" from the shoulder.
10. Milled a 'half-hole' every 30 degrees, resulting in a 12-point 'serrated' knob. (I'm sure there's a more technical term for this, but I don't have a clue what that might be.)
11. Took the knob back to the lathe, rounded over the edge and, using the compound slide, milled a slight taper on the face of the knob.
12. Still have some sanding and polishing to do, but it turned out pretty nicely. (See the pix below.)

Now for a question: That was a lot of work!!! The entire time I was making this part, I found myself declaring there has got to be an easier way to do this. How would you go about making such a part? Which, if any, of the tools you described could have eliminated some steps and streamlined the process?

Long winded, I know, but hopefully it's understandable.

Regards,
Terry

View attachment 254705View attachment 254706View attachment 254707
Well, if you could have started from round stock, then the whole thing could have done pretty quickly on the lathe, in one setup, other than the notches in the O.D. Then the notches could have been done easily in a chuck mounted on the rotary table, or in a spindex.
 
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