Joe's 1000x600x200 steel and aluminium router started

[devmonkey]

I actually don't agree with the above. I used two moats about a third from each end. But what is a must, the epoxy must be wide enough to all for the mucus (or whatever you call it) on each side and use the very slow epoxy.

I guess whatever works for you.

I did some tests under the microscope before I did the actual pour, the epoxy shrinkage phase occurs after it has setup too much to freely flow and find level, this (as Boyan determined) is what causes dips around dam ends and bridge joins. I used West's 105/209 and the shrinkage phase starts after about 1 hour by which time it is getting too viscous to re-level itself. The way I saw it is the bridge is only effective before the shrinkage starts and after it starts you want the area x-section of the epoxy you want to keep to be as consistent as possible meaning you have to extend it past the ends of the machine and you want the bridge to be connected to a part you don't want to keep as it either it will pull from the sides or the sides will pull from it. Either way it doesn't matter as you are going to cut this bit off.

The microscope method was stolen from the "Dam Busters" use of angled lights on the wing tips to determine they were the correct height above the water to drop their bombs. You point a laser pointer at an angle to the surface, focus the microscope directly down onto the point where the laser hits the surface and as the surface height changes the dot will move, magic ;-)