DIVIDING PLATE ..DIY ..Help...!!

[Steamchick]

Hi Indian,
Please can you add a picture of the back cover of the Zeus book? - It may help for those of us without the copy you have.
Thanks,
Minh-Thanh, without CAD I find this of little use, as I can't make a picture (but can copy yours!), but you seem to have a method that works for you. (What is pamme? - or panme? you seem to use 2 spellings?).
Is this "by eye" - or is it by indexing on x-y coordinates? I wonder if it as accurate as indexing off gears? (Indexing by gears systems had been used for a century of more before Mr Babbage invented his calculating machine).
Of course, without the change wheels on the lathe an alternative to gear indexing is needed. - So I should like to understand your method. It looks - from my interpretation of the picture - as if you are indexing by using a stop on the workpiece and indexing 9.23mm at a defined radius? - I can't figure how to do this on a blank after machining only the first tooth gap?
K2

 

[indian]

sorry have tried photos and scanning but the condition is awful but to the rescue comes YouTube . just do a search for bolt hole calculation there are several and among the best IMHO is Joe Pie ,tom stikkelman or r. dean Odell

 

[minh-thanh]

Hi K2
I read your posts in this thread but they don't fit what I have : I don't have odd gears , but your comments will help someone so I'm silent .
my fault : PANME
This is my idea

 

[BaronJ]

Hi Indian,
Please can you add a picture of the back cover of the Zeus book? - It may help for those of us without the copy you have.
Thanks,
Minh-Thanh, without CAD I find this of little use, as I can't make a picture (but can copy yours!), but you seem to have a method that works for you. (What is pamme? - or panme? you seem to use 2 spellings?).
Is this "by eye" - or is it by indexing on x-y coordinates? I wonder if it as accurate as indexing off gears? (Indexing by gears systems had been used for a century of more before Mr Babbage invented his calculating machine).
Of course, without the change wheels on the lathe an alternative to gear indexing is needed. - So I should like to understand your method. It looks - from my interpretation of the picture - as if you are indexing by using a stop on the workpiece and indexing 9.23mm at a defined radius? - I can't figure how to do this on a blank after machining only the first tooth gap?
K2

Hi Ken,

Free Download !

Check out "https://www.presto-tools.co.uk/Downloads" Counsellor

 

[fvd]

Back cover of the zeus book

From the book Precision hole location, by J. Robert Moore (1947):
39 holes, page 320 and 321.

 

[ajoeiam]

Hi K2
I read your posts in this thread but they don't fit what I have : I don't have odd gears , but your comments will help someone so I'm silent .
my fault : PANME
This is my idea
View attachment 159971

Almost looks like someone is trying to create a vernier protractor.

https://ia904708.us.archive.org/11/...changability in toolmaking and production.pdf

If someone wants the complete reference that mr fvd referenced - - - here it is. (above)

Looks like in attached pics

 

[trlvn]

Stepping back a little, this is for a gear hobber, right? The 39 tooth plate will create a 39 tooth gear? So any angular deviation in the plate will be faithfully transferred to the gear? (As compared to a dividing head with a 40:1 worm gear. There, only 1/40th of any deviation in the plate ends up in the work piece.)

If correct, then accuracy in creating the plate is exceptionally important. Really, there are only 2 basic approaches:

1) Turn the work to the necessary angle and drill.

2) (Use trig to) determine the x y positions of each hole. Move the work and drill.

Even without a DRO, I think 2) will yield greater accuracy. Use a spreadsheet to determine the absolute position of each hole. Taking care of backlash and carefully counting turns, it should be possible to place each hole within a couple of thous (0.05mm) of the desired location. Tedious: for sure. Accurate: better than trying to interpolate factions of a degree over and over.

My $0.05 worth,

Craig
(Using a CAD-produced template for hole locations is, in effect, just another way of using trig. But with human error introduced in the centre-punching process.)

 

[indian]

I have posted but its not appeared whats going on?

 

[minh-thanh]

Stepping back a little, this is for a gear hobber, right? The 39 tooth plate will create a 39 tooth gear? So any angular deviation in the plate will be faithfully transferred to the gear?

If correct, then accuracy in creating the plate is exceptionally important.

39 can also be 35 , it is used to cut odd gears .
Yes , accuracy in creating the plate is exceptionally important. I have made some gears myself, it is not precise but good enough for model engines, But to determine the precision needed for a homemade DIVIDING PLATE and make a good enough gear I don't know yet


Lots of interesting information
Thanks for the comments!!