I've been using my CNC on and off over the last couple of years, making parts for random projects but not really using its full potential. I recently had to make some plates for a keyboard a friend was making, and it had been nearly a year since I last used my CNC. It took a trial run to figure out the right feeds and speeds for my machine, but I was able to cut out some acrylic successfully for him.
However, during this quick run I saw the shortcomings of my CNC (and remembered how the last "upgrade" reduced my machine's rigidity) and decided to completely replace out the gantry. A significant amount of flex came from these unsupported x-axis pipes and I wanted them replaced with supported rails.
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| Added a steel bar so the bearing blocks don't roll independently. |
After adding a temporary fix to the old gantry, it was time to start anew.
I bought some SBR20 rail, 8020 extrusion, and some screws that I didn't already have in my collection of random screws from overbuying for previous projects.
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| Parts arranged how they will go together. |
In the span of a week after my summer internship ended, I steadily pieced everything together and got the gantry installed.
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| SBR20 rail installed into tapped holes. |
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| Scrap piece of wood used as a mounting plate. |
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| Nut mount for the plate. |
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| Screw installed. |
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| Old gantry. |
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| New gantry. |
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| Complete. |
Spent some time figuring out how to use CAM in Fusion 360 and will likely be doing all my CAD/CAM all in Fusion now.
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| Test engrave of China. Seems to work fine. |
Some things to fix:
The original bearing blocks for the y-axis rails have become loose (as expected with screws threaded into wood) and will need to be replaced with aluminum. The blocks also have some independent wiggle (issue that arose from the last upgrade) and I will likely need some more brackets to strengthen the gantry.
Now that the y-rails are further apart (due to my lack of planning; I really should have just used 1530 extrusion for the vertical beams too but no big deal), they extend over the edge of the wood sides and are currently only supported by a couple of bolts on the edge on top of far too thin aluminum angle (the only hardware I had on hand). This need to be beefed up and properly aligned to be square the the other axes. When installing the axes I only rolled the gantry back and forth hoping for the right alignment. The rails about 1/8" too far apart so the bottom extrusion of the gantry isn't flush.
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| Haha. |
