John's Alu Profile build

[Evengravy]

Progress over the last few weeks has been okay, I've had a bit of time here and there to get things together.



I've fitted the machine to the epoxied concrete base now, I ended up using 40mm steel angle (5mm thick) on both sides of the Y rails (inside and outside). These angles were drilled to accept 6mm bolts into the aluminium profiles every 80mm and were fitted to the base by drilling with an 8mm masonry bit to 80mm depth and bolted down with 24 of 75mm x 8mm Thunder Masonry bolts/anchors each side (https://bit.ly/32X7aeP). I chose these anchors as they are said not to stress the concrete when fixing, can be removed are strong and well plated against rust. I don't know what the pull out specs are for these but I'm guessing they'll be more than good enough for this application.

This thing seems really solid now. The overall job of fixing the machine to the base took a little longer than I predicted as there was an alignment issue with the machine causing it to be 1mm wider at the rear than the front (measured between Y rails). This was caused by a less than perfect alignment of the plates which connect the gantry at each side to the Y rail carriages. To rectify I had to remove them, probe them in on my other cnc an re-machine the bolt holes. I replaced M5 hardware at that time with M6 and at the same time and counter sunk the socket head cap screws. After some careful adjustment and refitting it seems to be rectified.

The metal work on the angle iron/steel took longer than I expected it to, I got it done with some persistence in the end anyway. Steel angles are all painted now (I ran out of black) to protect from rust a little but I have to order in some other paint for any remaining steel parts (gantry to ballscrew brackets).

Next up is rigging up the wiring and figuring out the cable chain management on the Y axis, I should make some progress on that this weekend (welding up some brackets at least).



At that point I should be able to get it moving around so I'm looking forward to that. I have a few more stages to go though: workpiece hold down, vices and I'm planning on epoxy/granite filling the Y rails and potentially the gantry too.

Before I fill the gantry I intend to strap an equivalent weight to the gantry (I calculate an additional 10Kg approx) and run some performance tests to see if my rapids are altered significantly by the extra weight. The gantry isn't excessively long so I'm hoping the performance will be okay.