Thanks: 0
Needs Pictures: 0
Picture(s) thanks: 0
Results 16 to 24 of 24
-
22nd March 2014, 07:06 AM #16Philomath in training
- Join Date
- Oct 2011
- Location
- Adelaide
- Age
- 59
- Posts
- 3,149
All the dividing heads I've seen can tilt in one axis. A semi-universal will (usually) allow direct indexing as well as indexing using dividing plates. A universal dividing head will allow you to do that but also enable gears to be attached for differential indexing and couple to the mill table so you can do helical milling operations.
If all you wanted to do was put hexes or flats on the ends of round shafts then a spin indexer*/ super spacer*/ indexing head would be fine. If you wanted to have more divisions or cut spur gears then you need a semi-universal dividing head**. If you want to cut spur gears with difficult numbers of teeth*** (like t=127) or helical gears then you are likely to need a universal dividing head.
Michael
*All the spin indexers I've seen are restricted to integer numbers of degrees. All the super spacer indexing plates I've seen are restricted to integer divisions. Which one you get depends on what you want to do.
**Rotary tables with indexing plates are available but like S/U dividing heads are not able to cover every single division over a certain number. From memory the certain number for a S/U D/H is 50 (ish)
***Of course, you could use special plates or compound indexing but that's a whole new can of worms
-
22nd March 2014 07:06 AM # ADSGoogle Adsense Advertisement
- Join Date
- Always
- Location
- Advertising world
- Age
- 2010
- Posts
- Many
-
22nd March 2014, 02:53 PM #17GOLD MEMBER
- Join Date
- Jul 2010
- Location
- Melbourne
- Posts
- 7,775
Ok maybe we forget the names and just call them by what they do
Direct Indexing
Indirect Indexing
Differential Indexing
????
Found something that I thought was interesting(even if I've never seen a table like it). A indexing head that wears in not out. (Of course there is a table that can use a sine bar to set angles between the steps.)
I can post a scan of one page of a book right? hope its readable
Stuart
-
22nd March 2014, 04:30 PM #18
I like the self correcting error idea.. very clever.
So for nomenclature we have... in order of accuracy?
Spin indexer
Super Spacer
Direct Indexing
Rotary Table must fit in here somewhere?
Indirect Indexing
Differential indexing
and not sure where to put the latest addition to the family...
Indexing table with meshing radial serrations.. ( super accurate, but I think only integer degrees? )
Ray
-
22nd March 2014, 05:06 PM #19GOLD MEMBER
- Join Date
- Jul 2010
- Location
- Melbourne
- Posts
- 7,775
Hi Ray
Yes that's what I though was so interesting.. the more you use it the better it gets as long as you arent repeatedly using the same angles.
I guess you could use a worn rotary table to make one then use that table to make another one and be pretty damn close.
Making dividing plates is about the only other thing I recall that can "self improv", though thats a little different.
Well not exactly what I meant.
Spin indexer, super spacer, some rotary table, some dividing heads= direct indexing
rotary table, dividing heads, things with worm wheels etc= indirect indexing
Dividing heads that are geared to another axis=Differential indexing
Lets not even start on dividing heads with 2 axis indirect indexing
So the one device might well come under to or even three headings... just depending on how its being used.
Its not really an order of accuracy.... that would me more about who built it. I remember Greg showing some pictures of a optical indexing head that the had a correction table supplied to correct errors in the worm wheel even though every wheel was lapped it a new lap etc etc.
" but I think only integer degrees? ) "
No, as I tried to say in my last post, there is a model that takes care of that.
I wonder if anyone has ever seem one in the flesh? lol... looks light
Stuart
-
23rd March 2014, 12:00 PM #20Distracted Member
- Join Date
- May 2010
- Location
- Lower Lakes SA
- Age
- 58
- Posts
- 2,557
Stu, remember the Hirth Coupling thread? I bet that is the principle at work here.
I still haven't got around to making one, but building a simple indexer sounds like a good excuse.
Oh wait, I have all this other stuff to do...
PS: It was actually in your shaper thread, regarding adjustable tool holders:
https://www.woodworkforums.com/showth...th#post1213831
-
23rd March 2014, 02:03 PM #21SENIOR MEMBER
- Join Date
- Oct 2008
- Location
- N.W.Tasmania
- Posts
- 703
I'm not sure, but I was under the impression that Spin Indexers could theoretically divide down to a tenth of a degree, courtesy of a vernier action with the choice of detent hole.
Rob.
Ahh, I may just have seen some light. It would seem that the vernier action was to get individual degrees, not the tenths I was confusing myself with.Last edited by Ropetangler; 23rd March 2014 at 02:16 PM. Reason: To open my gob in order to change feet.
-
23rd March 2014, 02:51 PM #22Cba
- Join Date
- Aug 2007
- Location
- Melbourne
- Age
- 68
- Posts
- 1,417
Ray, to mud the waters even more you could add the rotary table to your list. It is indeed a confusing theme. Essentially they all do some sort of dividing, but each are optimised for different tasks.
The "Hartford Super Spacer", as well as an "Indexing Head" or a "Spin Indexer" all belong to the category of Indexers. Indexers do not use an "analog" drive like worm gears to set angles or divisions. Indexers use a "digital" type of mechanical indexing. Most usually this is an exchangeable indexing plate with square teeth, but sometimes a hole plate or a common gear is used as the indexing plate. Sometimes the indexer is as simple as a number of equally spaced holes drilled at the circumference of a chuck or it's backplate.
Anyway, an indexer always has an integer number of divisions, it cannot be set to any arbitrary angle in between. Sometimes it is easily possible to convert a fixture back and forth from "digital" to "analog" dividing modes, by disengaging the indexing feature and instead engaging a worm drive (with or without indexing discs). Or you could use a CNC approach, with a step motor driving a worm drive, which would let you choose either way how to use it (either as a divider or to set any random arc or angle).
The advantage of a (digital mechanical) indexer is speed, reliability and ease of use, as it can very quickly be set. Imagine an indexer based on a gear with 24 teeth. Move it 12 clicks to divide by 2. Move it 8 clicks to divide by 3. Move it 6 clicks to divide by 4., and so forth. Very quick and easy to drill holes in a flange or the like, and it is hard to do a mistake too. But there is no way with a 24T indexer to divide by 5 or 7 or 9 or 10 or 11.... So you may need a number of different index plates.
A "Spin Indexer" is usually a simpler design than a "Dividing Head", made to accept collets, not tiltable, and fitted with a hole plate and vernier. There are motorized versions too, but unlike CNC controlled dividing heads or rotary tables, these motorized rotary indexers can only index to the steps given by their hole plate. Not to any arbitrary angle.
-
23rd March 2014, 09:52 PM #23GOLD MEMBER
- Join Date
- Jul 2010
- Location
- Melbourne
- Posts
- 7,775
-
24th March 2014, 01:28 AM #24.
- Join Date
- Nov 2008
- Location
- Perth WA
- Age
- 71
- Posts
- 5,650
Real basic and a bit less.
One day how about something like this....
Hercus' simple indexing attachment for their vertical milling attachment - https://www.woodworkforums.com/showth...96#post1403096
or if you like knurling -
$T2eC16FHJIkE9qU3iLVjBRYyt18Hl!~~60_57.JPG$T2eC16d,!w0E9szN,F46BRZFQ2g8Ww~~60_57.jpg$T2eC16JHJHgE9n0yEYejBRZFQ6zuPw~~60_57.jpg
BT
Similar Threads
-
Homemade Indexing/Dividing Device
By Jors in forum METALWORK FORUMReplies: 4Last Post: 2nd October 2012, 03:33 AM -
dividing plates, dividing head
By eskimo in forum METALWORK FORUMReplies: 22Last Post: 4th August 2012, 06:17 PM -
oak spacer sets
By humff in forum ROUTING FORUMReplies: 2Last Post: 31st July 2010, 03:32 PM -
Super simple, super cheap saw stabilization bracket
By toddles in forum TRITON / GMCReplies: 3Last Post: 1st September 2006, 01:15 AM