Indexing Jig

[smokeshow]

I'm currently in the process of designing/creating/fabricating a indexing jig. I have it currently designed for 5°, 4°, 3°, 2°.

Still working out all the details. (New to the lathe/shopsmith world)
Any thoughts/suggestions/comments/ideas would be greatly appreciated.

[smokeshow]

Thinking about dropping the 4° to make fabrication faster. Since it is kind of redundant with 2° already being able to be used.

[reible]

That should be in interesting project. I am assuming you have a CNC of some sort to do the holes?

I have one I purchased. It has been fine for everything I've needed. The wheel has sets of 4 hole patterns, 14, 36,48 and 60. This allows for:
20 obvious, symmetrical, evenly spaced layout combinations, as well as hundreds of asymmetrical layout combinations.

14 Hole pattern makes 2-7-14 evenly spaced layout options
36 Hole pattern makes 2-3-4-9-12-18-36 evenly spaced layout options
48 Hole pattern makes 2-3-4-6-8-12-16-24-48 evenly spaced layout options
60 Hole pattern makes 2-3-4-5-6-10-12-15-20-30-60 evenly spaced layout options

The finest adjustment is the 60 holes spaced 6 degrees apart, followed by 48 holes 7.5 degrees apart, then 36 holes that are 10 degrees apart. The final is 14 holes with the 51.4 degrees....... This is not a standard but common hole spacing.

You will also need a way of using this on your shopsmith. For an example of how I do mine take a look here:

http://www.shopsmith.com/ss_forum/gener ... t6075.html

There are other ways but I would say that the mounting is as important as the wheel.

I'm not sure of what you intend but I'd say take a look at some commercial index wheels to see what they do, things like lathe chucks sometimes have an indexing pattern on the back side as well, super nova 2 has such a pattern, and I'm guessing others might as well.

Ed

[smokeshow]

My design has 2° 3° and 5° spacing.

180 holes, 120 holes and 72 holes...

[smokeshow]

Just curious, but I come up with 7 holes at 51.4°. You are saying that it's 14 holes? Maybe I don't fully understand the math. I thought I did. But you post/design looks good. So, I am assuming that you have more experience with this.

[reible]

Sorry I didn't do the math just looked at the wrong place in the chart....

2 hole pattern = 180° between holes
3 hole pattern = 120° between holes
4 hole pattern = 90° between holes
5 hole pattern = 72° between holes
6 hole pattern = 60° between holes
7 hole pattern = 51.4° between holes
8 hole pattern = 45° between holes
9 hole pattern = 40° between holes
10 hole pattern = 36° between holes
12 hole pattern = 30° between holes
14 hole pattern = 25.7° between holes
15 hole pattern = 24° between holes
16 hole pattern = 22.5° between holes
18 hole pattern = 20° between holes
20 hole pattern = 18° between holes
24 hole pattern = 15° between holes
30 hole pattern = 12° between holes
36 hole pattern = 10° between holes
48 hole pattern = 7.5° between holes
60 hole pattern = 6° between holes

What do you intend to use this for with that fine a resolution?

Ed

[smokeshow]

Flutes, spirals etc... I just assumed that one needed precision, in order to do indexing. Again, I am new to this and just didn't fully know/understand. So, your saying I should scale it back/down?

[JPG]

Flutes, spirals etc... I just assumed that one needed precision, in order to do indexing. Again, I am new to this and just didn't fully know/understand. So, your saying I should scale it back/down?

You need to think in terms of segments(# flutes etc.) rather than degrees.

From a practical standpoint, needing a large number of segments for fluting etc. is unlikely.

Looking at Ed's initial list note 'most' are available below 20°.(11,13,17,19 are missing)*

Segments in this context refers to fractional parts of a circle only.


* Prime # BTW

[smokeshow]

Flutes, spirals etc... I just assumed that one needed precision, in order to do indexing. Again, I am new to this and just didn't fully know/understand. So, your saying I should scale it back/down?

You need to think in terms of segments(# flutes etc.) rather than degrees.

From a practical standpoint, needing a large number of segments for fluting etc. is unlikely.

Looking at Ed's initial list note 'most' are available below 20°.(11,13,17,19 are missing)*

Segments in this context refers to fractional parts of a circle only.


* Prime # BTW

Okay, so I only have part of the picture and I'm over complicating things, is what you are saying?

I mean, I may end up doing/trying other design/details later. I just thought I would need that level of precision/accuracy.

[JPG]

You are thinking like an engineer* rather than a woodworker.

Process orientated rather than goal orientated.




*Takes one to know one!