Dividing Head for a Tom Senior Light Vertical

[addjunkie]

My bed only has two T-slots (the Centec), so the spacing was not close enough. Taiwanese was considered less good, compared to British engineering and Japanese offerings - at that time. Of course, China has since taken over a lot of the supply. Taiwanese is definitely considered better than chinese.

IF that table is original, there are probably at least a couple of errors in there.

The maths is so simple, once you decide which hole circle you will be using for any particular tooth count. You know the number of holes per circle chosen, so just multiply that by 90 (turns) for the toal number of holes for 360 degrees and then divide that total number by the tooth count/spaces required. Convert that to whole turns and ‘holes’ - and there is your answer. So very simple…. If it doesn’t work out to an exact whole number of holes (actually ‘spaces’) you know you have got it wrong!

Also make sure you wear your reading glasses when setting it all up. Trust me when I say a 29 tooth wheel and a 28 one look very similar. And you dont realise until your finished.

 

[addjunkie]

They may look similar, but they will be of different diameter for the same DP/MOD.

Was counting the teeth your error?

No picked the wrong set of holes with out my glasses

 

[Agroshield]

The laminated chart is correct.

It is the one in the factory manual (purple cover) that is said to be suspect.

Any chance of a close up of the chart top left of your picture? It looks similar to the union flag plot Pete. showed beofre for a surface plate.

Attached is a text file giving divisions per hole hole count per plate, as well as all divisions possible and missing divisions to 100. It's not worth printing out but might be useful for reference if you need to see at a glance if a certain value is possible.

 

[Rannsachair]

The laminated chart is correct.

It is the one in the factory manual (purple cover) that is said to be suspect.

Any chance of a close up of the chart top left of your picture? It looks similar to the union flag plot Pete. showed beofre for a surface plate.

Attached is a text file giving divisions per hole hole count per plate, as well as all divisions possible and missing divisions to 100. It's not worth printing out but might be useful for reference if you need to see at a glance if a certain value is possible.

Thanks.

Top left sheet is: