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Indexing Jig
Posted: Fri Jul 27, 2018 4:06 pm
by 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.
Re: Indexing Jig
Posted: Fri Jul 27, 2018 5:25 pm
by smokeshow
Thinking about dropping the 4° to make fabrication faster. Since it is kind of redundant with 2° already being able to be used.
Re: Indexing Jig
Posted: Fri Jul 27, 2018 8:18 pm
by 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
Re: Indexing Jig
Posted: Fri Jul 27, 2018 9:14 pm
by smokeshow
My design has 2° 3° and 5° spacing.
180 holes, 120 holes and 72 holes...
Re: Indexing Jig
Posted: Fri Jul 27, 2018 10:03 pm
by 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.
Re: Indexing Jig
Posted: Sat Jul 28, 2018 12:51 am
by 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
Re: Indexing Jig
Posted: Sat Jul 28, 2018 6:14 am
by 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?
Re: Indexing Jig
Posted: Sat Jul 28, 2018 9:20 am
by JPG
smokeshow wrote: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
Re: Indexing Jig
Posted: Sat Jul 28, 2018 10:07 am
by smokeshow
JPG wrote:smokeshow wrote: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.
Re: Indexing Jig
Posted: Sat Jul 28, 2018 10:22 am
by JPG
You are thinking like an engineer* rather than a woodworker.
Process orientated rather than goal orientated.
*Takes one to know one!
