Yesterday, Rob very kindly printed a few more components for my 3D printer: a stepper motor mounting bracket, the top end idler pulley bracket, an idler pulley and a drive pulley. The drive and idler pulleys are version 2 components. I had to modify them to allow for a phenomenon I’m choosing to call squeezage. This is the behaviour of molten plastic which causes it to extrude slightly sideways when deposited from above, resulting in circular holes being slightly smaller in diameter than expected. I don’t have a lathe (yet), so I was unable to modify the version 1 pulleys with enough accuracy to make them fit the bearing and shaft. Here are the new components:
And here are pictures of them all fitted to the printer frame:
As you have doubtless come to expect, most of the pictures (the ones not taken with a phone) are blurred because of my camera’s focusing fault. I really must buy a new camera.
This morning I fitted the high-strength fishing line I’m using in place of a drive belt, set the tensioner in place, temporarily wired up the controller board and fired up Pronterface to see if I could make the carriage move up and down. Astonishingly, everything just worked. You can see a (rather dull) video of it on YouTube if you really have nothing better to do. If you can bear to watch right to the end of the video (it’s only a couple of minutes), you’ll get some idea of the size of the printer. It’s a bit bigger than I originally intended – but if I ever need to print something the size of a traffic cone, I’ll be well set up.
The next step is to do some tests to see how accurate and repeatable the motion is. When I’m satisfied with that, I’ll fit the other two sets of drive components, and then it will be time to connect up the print head and its support arms. Watch this space.
