# Spin indexer and gears



## Hukshawn (Nov 6, 2017)

I'm having a dilemma over a rotary table. 
I'm looking for a 6" rotary table for Christmas but everything is out of budget. There was one on Amazon that would have been perfect, came with a tail stock and dividing plates but it sold out and is no longer available to Canada. All the rest are only available to the states and I have no way to get it shipped to Canada. 
I really need something to make gears. 
So, spin index... Possible to do a reasonable range of gears or no? Most are 5C collet, I believe, I can rig up a tail stock and turn a gear on a shaft, but the degrees... My understanding is they are in 5 deg intervals. 

Anyone have experience? I need advice. My wife is asking me to make a decision.


----------



## jocat54 (Nov 6, 2017)

http://www.hobby-machinist.com/threads/poor-man-dividing.63601/


----------



## JimDawson (Nov 6, 2017)

Mine are 1° increments and 5C collet.


----------



## Hukshawn (Nov 6, 2017)

jocat54 said:


> http://www.hobby-machinist.com/threads/poor-man-dividing.63601/



So, a viable option for gears? 

With the vernier scale, does that give the indexer a positive stop when you turn it? I've never handled one before...


----------



## jocat54 (Nov 6, 2017)

I think it would be viable.
The indexer gives a positive stop and there is a hand screw that tightens against the spindle of the spin index. Sort of locks it in place
I think most spin indexes are capable of 1 degree, so any number that will divide evenly into 360 can be done with the stock index (360/18=20)---all others would need the extra discs made (360/26=13.846) so to make a gear with 26 teeth you would need a disc with 26 holes.
Hope i made some sense with that

You are really cutting spaces to create teeth.


----------



## Hukshawn (Nov 6, 2017)

Am I going to regret the purchase in 3 weeks after I pull my hair out and ruin several years blanks...? Is that likely? 

I feel like I am settling for a spin indexer.


----------



## RJSakowski (Nov 6, 2017)

I have a Phase  II with 1º increments and a tapered pin for indexing.  You could cut gears but would be limited as to the number of teeth.  The options are 6, 8, 10, 12, 15, 18, 20, 24, 30, 36, 40, 45, 60, 72, 90, 120, 180, and 360.  (There's also 1, 2, 3, 4, & 5 but they're not really practical.)  

It is possible to modify a standard indexer by making a special plate that  would have the correct spacing for other gears as John pointed out.  A disk with 78 holes would make 13, 26, 39, and 78 tooth gears; a disk with 56 holes would make 14, 28, & 56 tooth gears; etc.  It's not really practical to try to cover a large range of gears.

Another problem could be rigidity.  The gear would be mounted to a shaft which fit a 5C collet, maximum diameter 1.125"  Any larger gear blanks would be flexing with the cutting forces.  You could create a fixture to support the blank  better. though.


----------



## Chipper5783 (Nov 6, 2017)

Stick with game for a while and you will end up getting a dividing head and a spin indexer.  In other words, get the spin indexer now and use it.  The spin indexer is not going to do everything for you, so in a while you'll got a dividing head.  You will still find that the spin indexer is usefull.  You will still discover that the spin indexer and the dividing head does not cover all the bases, so you will talk yourself into getting a rotary table.  That will be great, and after a while yet another project will come along that will require yet another purchase.

Be warned, there is always another tool or attachment.  Get the spin indexer, they are handy enough.  They are pretty light duty, which is fine, go easy and you can do good work with them.

My photo is of a bunch of change gears that I made.  I used a dividing head.  There is quite a range of tooth counts - the spin indexer would not have worked.  The dividing head is a pretty big lump of iron, I use the spin indexer more than the dividing head, because the SI is little and handy for small stuff.


----------



## RJSakowski (Nov 6, 2017)

Shawn, take a look at this. http://hobby-machinist.com/threads/poor-man-dividing.63601/


----------



## Hukshawn (Nov 7, 2017)

Chipper5783 said:


> Stick with game for a while and you will end up getting a dividing head and a spin indexer.  In other words, get the spin indexer now and use it.  The spin indexer is not going to do everything for you, so in a while you'll got a dividing head.  You will still find that the spin indexer is usefull.  You will still discover that the spin indexer and the dividing head does not cover all the bases, so you will talk yourself into getting a rotary table.  That will be great, and after a while yet another project will come along that will require yet another purchase.
> 
> Be warned, there is always another tool or attachment.  Get the spin indexer, they are handy enough.  They are pretty light duty, which is fine, go easy and you can do good work with them.
> 
> My photo is of a bunch of change gears that I made.  I used a dividing head.  There is quite a range of tooth counts - the spin indexer would not have worked.  The dividing head is a pretty big lump of iron, I use the spin indexer more than the dividing head, because the SI is little and handy for small stuff.



This is likely more of what I needed to hear. All the gears I'll be making are brass, and likely with a fly style cutter... I would be adding a 5" chuck to the spindle of the indexer and a tail stock. So some added rigity there. I can't afford a dividing head. So the choices are a rotary table that will chew my budget, or a spin indexer that will leave room for any extra tooling necessary. But I wasn't sure if it would work. 
I have igaging dro's, they don't have the extra features that the bigger dro's have. 

It sounds like The indexer will do the same as a rotary table as far as gears go, at a much cheaper price. I don't know what the teeth counts are at the moment. I'd have to go inspec them all and check the many lists shown. I'm sure I could figure out a way to get it to cut an odd number of teeth not listed.


----------



## Hukshawn (Nov 7, 2017)

Figures... the first gear I'd be making has 50 teeth. But the second has 20. So I'm 1 for 2...


----------



## jocat54 (Nov 7, 2017)

Shawn you could use a online calculator (like LMS bolt hole calculatorhttps://littlemachineshop.com/mobile/bolt_circle.php  to get the coordinates for each hole and use the igaging dro, that's how I did it when I had my mini mill with the igaging dro. Little more work but very doable.


----------



## Hukshawn (Nov 7, 2017)

jocat54 said:


> Shawn you could use a online calculator (like LMS bolt hole calculatorhttps://littlemachineshop.com/mobile/bolt_circle.php  to get the coordinates for each hole and use the igaging dro, that's how I did it when I had my mini mill with the igaging dro. Little more work but very doable.



Ohhh look at that! Thanks!


----------



## Doubleeboy (Nov 7, 2017)

Why not just build your own small dividing head, lots of plans out there on the net.  If you decide to save your $ to buy one get a Vertex, not cheap but then again its a fine machine.


----------



## chips&more (Nov 7, 2017)

If your primary need is to make gears. Then IMHO you do not want a spin indexer or a rotary table. You will get the best results using a “dividing head”. And better yet, a CNC dividing head. With a CNC type, you can get all the divisions (some divisions with very slight errors) with the push of a button(s). Sherline has a pretty nice 4” rotary table and can be had with a CNC package. For a manual, the little Ellis dividing head is pretty darn nice…Dave.
	

		
			
		

		
	

View attachment 246201


----------



## Hukshawn (Nov 7, 2017)

My budget is $350 max.


----------



## Hukshawn (Nov 7, 2017)

jocat54 said:


> Shawn you could use a online calculator (like LMS bolt hole calculatorhttps://littlemachineshop.com/mobile/bolt_circle.php  to get the coordinates for each hole and use the igaging dro, that's how I did it when I had my mini mill with the igaging dro. Little more work but very doable.



I am able to borrow a friend's 8" rotary table, I just have to go pick it up. I think I will try a test with it and the LMS really handy form. I can use the degrees to turn the gear. 
This first shot will be a 50 tooth clutch gear for the spindle fine feed. The teeth are on the face not the diameter and cut with a engraving cutter/bit. It won't need to be laser accurate, as long as the teeth engauage with the other gear I have. We will see how it goes. For the accuracy I'm going for, if I'm .2 degrees off, I don't think it'll ruin everything... Who knows.


----------



## Asm109 (Nov 7, 2017)

http://www.shars.com/products/toolh...g-heads-spacers/7-7-8-precision-dividing-head

Just over your budget but exactly what you need.


----------



## DAT510 (Nov 7, 2017)

It would end up a bit more than your budget, but you might take a look at the Vertex Rotary Tables.  90:1 ratio, Optional: Dividing Plates, Tail Stock and Chucks.  I ended up purchasing a Vertex HV6 rotary table.  The base HV6 starts at around $250. Hamilton Tool & Supply had some of the better pricing, I could find.   Shars also sells a similar rotary table, though I don't know who makes it.
Stefan Gotteswinter has nice review and series of "upgrade" videos on youtube for the Vertex HV6.


----------



## Hukshawn (Nov 8, 2017)

So, i borrowed a friends 8" rotary table with an adorable 3" chuck mounted on it.
I used the LMS form jocat54 posted, man, what a useful tool..
i used the degrees to advance. It was quite easy actually.. the hardest part was centering in the bore. I used a small edge finder inside the bore as I don't have an indicator holder that clamps to the spindle. I bought one two weeks ago but returned it cause it was junk. Breath on it and it moved...
Anyways. I made a D cutter, and it worked perfectly. Really happy.


----------



## MarkM (Nov 19, 2017)

You can make your own plates with coordinates with trig.  X using sine y using cosine times the radius.  For simple math example a four hole plate. 360 divided by 4 is 90. First hole is just your radius.  Next is radius times sine of 90 for the x coordinate and y is radius times cosine of 90.  Your next hole is 180'degrees and so on.  You ll have four quadrants  of x and y which simply is top bottom and left and right.  Make any plate you need. Use degrees minutes and seconds and not just a decimal for non divisible numbers.


----------

