Indexing

[Bill Alston]

I bought an indexing disc that fits behind my chuck. It had 14, 36 and 48 holes. This seemed a bit limiting given the size of the disc so I added smaller holes between the ring of 36. This gave me an additional index of 72.

I would now like to make another smaller indexing disc for another project but this time I’m thinking 36, 48 and 60 may give me a better range. What do you folks think? I like pictures so if you have any of your shop made Indexing setups please share.

 

[hockenbery]

My lathe has a 48 index wheel. Which has the layout combinations I can make from 2,2,2,2,3

I most often use layouts with 3 or 2. Spirals I can layout with 6, 8, or 12.
Once in a while I do a layout with 7. Never got around to making a wheel. For my purposes I end up fudging with a paper printout or using my wheel index at 6.9, 13.7, 20.6, 27.4, 34.3, 41.1, 48. It’s accurate enough for laying out spirals to carve.

Obviously you need some way to anticipate what you might need or what gives you a new capability.

Looking at the factors of each ring lets you see the duplication and unique divisions on each ring.

Ring - Factors
14 - 2 7
36 - 2 2 3 3
48 - 2 2 2 2 3
72 - 2 2 2 3 3

60 - 2 2 3 5



Spring 2004 American Woodturner has an article by Paul fennel on a simple index design

 

[john lucas]

I have 4 index wheels. The ironfire has 14,36,48,60. The alisam has 16,90,120,144. The chefwarekits has 56,88,96,120,144,192. Then I have a flat disc with no holes. I make marks on it fir any odd-numbered not on the other ones like 9,11,13 etc. You can also ho online and find programs to print out any number.

 

[William Rogers]

I have the Alisam. However I made 15-20 wheels by printing an index, laminating it, and gluing it to a piece of wood. Then made an index indicator from plexiglass. I gave them to club members. It actually worked fairly well and for sure was cheap. See photo.

 

[Bill Alston]

Thanks for your thoughts folks.
These are the factors of the numbers I mentioned:

1, 2, 7, and 14.
1, 2, 3, 4, 6, 9, 12, 18, and 36.
1, 2, 3, 4, 6, 8, 12, 16, 24 and 48.
1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, and 60.

I’ve never used the 14 hole ring on my existing plate.

Using the other three I’d get the following divisions.
1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 16, 18, 20, 24, 30, 36, 48, and 60.

Which seems a pretty good range of divisions. I don’t think I’d ever need to go beyond 60 but I’m going to be limited by the size of the disc anyway. I’m actually hoping I can get up to 60 on the plate.

 

[john lucas]

I just did 120 the other day. Here was the start.

 

[J. Paul Fennell]

My Oneway 2436 has 96 divisions built in. However, I use the Microsoft Excel program to create pie charts for any unusual number of divisions when needed, like in the attached file.

 

[Don Wattenhofer]

The system I use "spin index fixture" is different then the index plates, but you can do any amount of divisions that can be divided into 360 and equal a whole number of degrees per division. Example: 360/ 7 = 51.4285 will not work because there are 360 possible positions an no way to set a decimal value however 15 divisions = 24 degrees per division so first stop starting at 0 degrees, 2nd stop at 24 d, 3rd stop at 48 D, 4th stop at 72 D etc.
This is not necessary for strictly ornamental indexing, but the project shown in the picture will result in near perfect glue joints in the zig zag setup.

 

[Darryl Fective]

My first indexing wheel was made with a ring gear from an old truck engine. It has 180 teeth which divides into a decent number of cuts, but I upgraded to a Chefware Kits 12" index wheel. It has a lot more flexibility for cuts/spacing, and is also a lot safer. I bought just their wheel, without the rigid post with sliding pin, and created a flexible arm with a fixed pin which makes it both accurate and fast.

No pics of the new setup, but here's one of my old one.

 

[Doug Rasmussen]

This is a piece I've shown to tease the OT folks. I don't recall the exact number of indexes at least 360. Done with fine indexing so the surface doesn't show any evidence of faceting.