My Jones and Shipman 1300 EIUR cylindrical grinder spec says that it's swivelling table is 60" long.
Now I need more information than that as I am measuring linear displacement of the table end to set a very accurate angle. The pivot point of the upper table is totally obscured but I think that a fair assumption is that it is dead in the centre of the table. The ends of the table are radiused, but again obscured by the table clamps but I think that I can project a tangent from these radiused ends forwards past all the obstructions using steel rulers and set squares to measure between them to get the length at the point that I am making my linear displacement.
So now I (theoretically) have two steel rulers projecting into free space and I need to know the distance between them - what options do I have:
A/ Tape measure - I'm sure that this isn't accurate enough - my displacement is to tenths of a thou !
B/ Using my Leica Disto laser measurer, but it's only accurate to 1 mm
C/ Length Bars - I don't have any and certainly don't have enough Jo Blocks to stack up to 60 inches !
Now the accuracy of the 60" leg of my triangle can be less than the displacement (about 3.5") by swivelling the table by the ratio of their lengths and keep the same overall accuracy (I think) but any geniuses out there do please comment !
. . .all suggestions welcomed
![:thumbup:](https://madmodder.net/Smileys/default/happy0034.gif)
(best guess so far using a carpenters steel tape gives about 58.75" )