Quote Originally Posted by Jonathan View Post
Not fair! I hope it doesn't turn out to be a difficult grade to machine.
It was far less than I was prepared to pay so was well happy.....I'll find out if it is difficult when I send some pieces to Haydn to machine for me. I've still got to do the calcs and design the bearing housings etc. Where would the best place be to have the ball screws on the X axis, they seem to be sticking out quite a long way. Would it be better to have them under the 50x50 box that the rails are sitting on?

Be careful with the amount of Z-travel on the MDF/aluminium machine. Clearly you want to have as small a Z-travel as possible to reduce the deflection from having a relatively weak Z-axis and gantry, but there still needs to be room to change tools. This could be a problem if you need to use drills, unless you buy short drills and/or have a hole in one corner of the bed which you jog the machine to for performing the toolchange.
As the tallest piece of balsa is likely to be 1" I'll look at lowering the gantry and reducing the travel. Want to reduce the gantry size anyway as the sum of all the lengths is just over 5m in length so just more than 1 length :)

Below is the sort of thing I'm looking to cut on the MDF router. No drilling, I'll be using mostly 2mm cutters (somethinig like this I guess 10x Carbide Drill PCB End Mill Engraving Bit CNC 1.2mm | eBay )in the E50 Proxxon I have but yes will look at height for tool changes.

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