DISCS:
We currently have 40 working discs and 26 discs that are out of tolerance. Today, I made an order with John in the electronics shop to cut 130 (4 for each disc: two for each piece) plastic shims that will be used to put these discs back into tolerance. He is also cutting 90 additional rubber ‘dots’. Assembly and troubleshooting instructions are on an earlier post on the blog. Howard is working on one more set of 9: if you find that the rework on the OOT discs fails, let Howard know that he will have to manufacture the rest as soon as possible.
TRIGGERS:
Steps to manufacture:
Assemble motes: IDC ribbon cable must be attached to the stripped motes. Phil was working on this when I left. I have cut and stripped more than enough (to meet the qty 75 target) cables to the correct length and have crimped enough to make 70 target. Eventually, we will need to order more connectors and crimp an additional five. To crimp these cables, use the cable on a working trigger assembly as a guide. The orientation is important. I have been using the green arbor press (moved from the DFM lab to our lab) to crimp the connector, but something such as a vise should work as well. The length is measured relative to the connector so that the cable should be crimped with the end of the cable roughly flush with the outside of the connector. EG, insert the cable into the connector latch in the correct orientation and line up the end of the inserted cable with the outside of the connector. Ensure that the cable is in straight and use the press to crimp the connector. It can be kind of tricky to get the cable in the press and make sure it stays straight at the same time. Keep in mind that the once the connectors have been latched they can not be reused or recovered. The cables should be attached to the mote first by soldering the four USB leads in order. There are three other cable pins that require connection: starting with the wire furthest away from the USB leads (call this wire 1), solder wires 1 and 3 together into the Vcc header pin on the mote. Solder wire 2 into the UserInt pin on the mote.
Assemble FSR boards: we should have all but 11 of the FSR circuit boards required for the 75 qty target. Eleven will hav eto be started from step 1. The circuit boards should be located in the gray materials cabinet. Population should be pretty straightforward with two exceptions: do not solder the digital potentiometer (4-pin DIP IC) and replace the 560 Ohm resistor with a 5K Ohm resistor. I’ve found that the solder spoon is very helpful when soldering the comparator and the header pins. We should have enough header pins for the rest of the 11; they are located in the parts cabinet drawer labeled ’0.1” headers’. You may have to clip more from the bulk headers. Gregg (and Geb) has experience in soldering these circuit boards. These eleven boards will have to be tested before deployment. This will be easier if the battery holder is not populated until testing is complete. After testing and the battery holder is attached, the solder pins and excess solder must be clipped from the underside of the board to ensure a good fit in the plastic housing. This has caused problems with the lids fitting. Make sure to clip every pin as close to the board as possible with special attention to the battery pins (which require larger holes and more solder).
Assemble triggers: the two boards can be assembled in any order, but not simultaneously due to insufficient clearance for the connector. Use two spacers under the bottom most mounting holes under the mote; the FSR circuit does not use spacers. I have been using 1/4” screws for the FSR board, but the plastic 5/16” screws work as well. The FSR board requires 3/16” screws. Assemble one board, attach the connector, and then assemble the other board. The assembled triggers then need to be tested with verified working pucks (set the trim pot to roughly half a turn).
Assemble lids: the plastic panels for the lids are in a plastic bag on top of the gray parts cabinets. I have used the blue Loctite superglue to attach them to the inside lip of the lids. Make sure that this inset is clear of plastic burrs or dirt before gluing. There are three holes on the panels: one for the switch, a circle for the button, and the largest hole for the USB receptacle. To align the panel, I place the panel laterally so that a little less than half of the material between the USB hole and the edge of the panel is covered by the lip on the puck lid. See an assembled puck for reference. You should also allow about an hour for the glue to cure. After all parts have been tested, assembly the lid to the trigger body using 9/16” screws. When I assembled 31 triggers, I encountered a >50% fit failure. This is mostly due to the trigger body flexing. Another cause is incorrect hole alignment between the one FSR circuit board mounting hole and the counterbore in the trigger body. To troubleshoot these problems, first ensure that the screw path from the counterbore to the screw hole is straight. If the mounting hole in the FSR circuit board is not aligned, remove one of the mounting screws (the one closest to the USB receptacle) on the FSR circuit to allow the board/mounting hole to float into alignment. If assembly still fails, it may be because the ‘top’ screw (that passes through the mote) is not long enough to engage its threads. I trimmed 3/4” plastic screws to be a couple millimeters longer than 9/16” (you may also try using 5/8” metal screws). Using plastic screws, you may find that the lid does not completely fasten to the trigger body, but the screw should stay in and prevent the top of the lid from rotating or flexing out too much.
PRO/E:
All current files are in S:\ProE\Current Puck 7-26. These files should be concurrent with Howard’s files and include both the MFG sequences and CAM code that he generated.