Quote Originally Posted by devmonkey View Post
Gantry extrusion has arrived from KJN, it is a real beast. KJN cutting appears very accurate.

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So now I need to decide how to mount 15mm rail to the extrusion. I was considering 3 options:
1. Mount rail directly to extrusion between the two slots, drilling and tapping.
2. Mount rail on aluminium plate which is in turn bolted to the slots.
3. Mount rail directly to slot.

This shows that the profile is not flat across the width which I believe is by design so that the slots pull up to meet whatever you are clamping to them. The slot edges are 0.15mm lower than the centre, the centre and the 2 corners are perfectly aligned within the resolution I can measure with finest feeler gauge.

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Now I have the extrusion (1) is a non-starter as there is a very slight peak in the centre and I would need to mill it flat which is hard given the gantry is longer than my mill table, although not impossible.
(2) is what many people seem to do and so obviously works but is more work for me.
Can I get away with (3), see picture below, what do you think?

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I have a 50mm fly cutter, it would be possible given the extrusion is already flat and parallel to fly cut between the high points, would have to tram the mill carefully first.
Hi
Is it SKU IR26526 profile?