Originally Posted by
handlewanker
Hi, I quite agree with the moving table design as it can be made more sturdy especially if you want to get ambitious and do a bit of steel milling.
I hypothesised with a different aspect ratio design for the table size, as the table Y axis length does make the base twice as long as the table due to spindle coverage etc..
Taking a 6040 for example.....in a moving gantry design the table is narrow ....400mm wide and passes under the gantry, but with a moving table type the base would be 1.2 metres long to allow the table to traverse it's 600mm length.
You could make the table Y axis the 400mm width and make the X axis the 600mm length which means the X axis crossbeam has to be only a bit over the 600mm wide to allow the spindle to move over the table length sideways.
If the 600mm table length does not pass between the gantry uprights the head has to stick out a long way from the X axis face to cover the 400mm table width.
So, as the uprights and crossbeam can be massive, it would be practical to allow the table to move a short distance under the crossbeam but not necessarily all the way as in a moving gantry type......this would reduce the spindle stick out from the X axis face quite a bit.
At no time would you want a long job to overhang the table sides.....it can overhang on the 400mm width as that is now the Y axis.
I think a table rapid travel in a 400mm Y axis can be a lot quicker than the corresponding normal 600mm table length......it's unconventional, but could be practical to keep the base length more compact.
Ian.