Hey,

It's been a while since I posted here, hope everyone is keeping okay. I haven't forgotten about the build and have been taking baby steps whilst I try to get someone to run an armoured electricity supply to the 'shed'. I insulated the place, painted the floor, fitted and painted the walls, build a solid bench and acquired two small lathes in the mean time (one is a emco cnc lathe with tool turret that I have been converting to Mesa/Linuxcnc at the same time, the other is a 'Chinese' manual lathe that I've been modifying with epoxy granite and some tapered gibs.)

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Anyway, back to the router; I have sourced a cast aluminium plate (15mm 5083) and am about ready to fix it permanently to the bed. For fixings, I intend to use the same hurricane bolts I used for the Y rails, that's all simple enough.

Before I started milling this plate I wanted to get everyones take on the bolt holes for fixtures. What spacing would you recommend? I did a design on 30mm spacings (similar to the Saunders Machine Works designs) but it came in at 1700 holes to drill and treadmill so I'm not sure I could manage that before I have the flood cooling system in.

I went and purchased some good quality carbide tooling though, for the drilling I went to cutwel and got a 5mm alu-specific parabolic carbide drill (made by YG-1 I believe) and thought that, maybe, with the right pecking cycle and some care I might be able to avoid gumming up the cutter with manually applied cutting fluid.

What's your take on M6 bolt holes spacings on a plate like this? Also, anyone have advice on speeds/feeds/strategies for dry drilling 5083 with parabolic carbide tooling? I haven't thread milled before so that's going to be fun.