Refining Dispensing

Once I knew the bracket connection worked on the carrier I laser cut more accurate parts (above) which worked even more effectively than my rough cut outs. The carrier is shown at full height in the photo above with the tracks showing the extent of the movement it can make

Another change in design has been with the dispensing arm which didn't move smoothly enough being mounted within the dispenser mechanism. To solve this problem channels have been added to allow the arm to pivot on mounts on the outside of the mechanism body. The movement of the arm is shown in the staged photographs above.

  

The movement clearly works as shown above. There are still issues which need resolving in terms of strength of the parts, particularly the control mounting joints. One requirement I have not looked at until now is then need for the arm to return to its upright position after dispensing. The standard dispensers use a leaf spring made of nylon to make the sculpt section return to its upright position. Wanting to again rely on weight rather than parts than could break, I attempted to make the arm reset itself using the same counter weight system as used on the carrier. To make a start point for the arm I added a 'buffer' on the top edge (see below). Whilst the method works with thread attached through a hole at the top of the arm cross bar (see below) there was a problem. The friction from the silicon on the arm moving backward seems too great for this method to work no matter how much weight is applied. Move the carriage downward and the mechanism works really well, resetting itself promptly. I will see how well this works with a more refined grip tomorrow.