Index Table - Dividing Head
Index Plates
Click to enlarge pictures.
The index plates are made of 6 mm thick discs that I have sawed a thick shaft.
For these discs to cut properly on thickness, I have used the chuck fill out disks of Project 2.
These have certainly proved their worth. Further explanation is superfluous here.
Drilling the holes I've done on the index table itself, using an EXCEL spreadsheet.
It is very easy to drill accurately the holes.
On the spreadsheet, enter in cell G1 the number of divisions.
Column B lists the number of turns of the handwheel.
Column C is the number of degrees on the handwheel.
In column D are the number of minutes lines on the handwheel.
In column E are the number of lines on the vernier.
The other columns are purely for verification.
The accuracy of the distributions is 0.5 minute.
You can also drill a test plate and then use this to drilling the final disc.
The accuracy is then 0.5/72 = 0.5 seconds.
Whit this set of index plates it is possible to make all divisions from 2 to 70
and most higher.