Y Axis Deflection?

[rb99]

I have an old machine with the 2 rail Y axis that I have beefed up here and there. The Y axis is about 5' wide. I tested it today with a dial gauge, and found that the with the router from the far side to the middle has a deflection or sag of 0.21mm or 0.008268 inches. Is this amount of deflection tolerable?

I have done some upgrading and in order to fit both the router and the dust shoe + hose in the middle of the Z carriage I have the Z Axis weight mostly on one rail. I am moving the Z to the center to balance the weight between the 2 Y rails, but I am going to do that down the road.

Thanks