Jigsolve: Improved hoses
Yesterday I went to NEWLINE hose & fittings in Burnaby, Canada, and picked up some new parts. The old model was the clear vynyl tubing and then a bearing to let just the tip rotate. Air was leaking through the two rings of the bearing. That made the suction at the tip too weak to pick up a jigsaw piece.
I suspect the final mechanism is going to be too large for the CNC head I’ve got. Lesson learned: get the tool designed first, THEN build the gantry that will hold the tool? No… that’s close…
When building a machine, I start by defining the goal, then work backwards from there. I needed a machine that would pick up jigsaw pieces and move them around from the internet. So the first thing I did was pick out a table for the jigsaw pieces, then build the biggest CNC I could on that table. Anyone else see how that’s backwards? Yeah. Looking back on it, it’s obvious.
So if I’m doing this the right way around, the immediate next goal is to get a nozzle on the end of this 1/8″ NTP brass 90 degree connector, and assert that it can pick up a jigsaw piece with the pump I have. Then build a mechanism A to rotate the nozzle. Then build a mechanism B to raise/lower mechanism A. Then attach that to the CoreXY. Etc, etc.
While I was there I learned about the threading on the 1/8″ NTP connectors. First off, the ones above are 27 teeth-per-inch, which we figured out with a Thread Gauge, a tool I’d never seen before. Neat! Also, the air-tight seal between two components is possible because the depth of the thread is tapered – as the parts are screwed together the fit becomes tighter. I was advised to tighten until I meet resistance and then give it an extra 1/4 turn.
The change to the milky white silicone tubing is to allow more flex when the nozzle tip rotates. I’m basing this choice off the uArm.
I’m also going to copy their idea for a rotation system, using some 3D printed parts to hold the brass fitting at the end of the tube on a hobby servo. Then all that will go on a second servo to raise and lower the mechanism, and the camera will be as close as possible to the lifter, which still having a view of the nozzle.
I’m going to try to make some nozzles that are all 1/8″ NTP at one end and different inner and outer diameters at the far end. For example, a nozzle for SMT components might be 1mm ID and 3mm OD. A jigsaw piece might need 3mm ID and 10mm OD, forming a wide flat suction cup.
Here is where I have a question for you:
Is it more efficient to
(A) make a few different designs at once and pick the best fit or
(B) make one, test, repeat until best found
?
