2024-12-23

Last modified: 2024-12-23 13:33:57

Frame

The screws for the frame still haven't arrived! I ordered them 2 weeks ago and delivery estimate was 2-3 days. I complained to the seller last week and they said they were out of stock and they could send slightly longer ones instead, but those still haven't arrived either.

So I've complained again, but also learnt my lesson and ordered from another seller.

In the mean time I can at least cut the frame parts to length. I want 4x 1-metre lengths, so those don't need cutting, and then from looking at CAD:

I think 13 horizontal pieces left-to-right, and 4 front-to-back? So 17 short-ish pieces. For convenience we could make those a bit under 25cm long and get 4 of them out of each 1-metre length, which would leave a ~75cm length left over, which should be enough to get the 2 shorter vertical pieces at the bottom.

So for now I think cut 17 pieces a bit under 25cm long. They are 200mm long in CAD, but making them longer gives me a bit more space, so "a bit under 25cm" will be fine.

And then when I have those pieces I can measure how long the shortest one actually is, and square them all off to that length on the CNC machine.

Great success, all done. They're 244mm long. In hindsight that is unnecessarily short, it would have saved time on machining if I hadn't taken so much off. But better to waste a few minutes of machining than to waste a piece of material because it isn't long enough.

The overall cycle time (finished part to finished part) was about 70 seconds, of which 60 seconds was machining and only 10 seconds was faffing about loading/unloading material, so pretty efficient really. I wrote the gcode by hand. I had it park the tool at the left hand edge after finishing, so that the position of the tool can be used to reference the position of the next piece of material.

I cut at 7200 rpm, full depth (20mm depth of cut), 0.5mm width of cut, 525 mm/min feed rate. Could probably have gone higher on rpm and feed rate to save time but this seemed happy so I left it along.