3d printed cable roller and waterproof control box for a Schill GT380 reel to turn it into a ROV or robot tether

thingiverse

To build one of these, you will need a Schill Gt380 plastic-rubberized cable reel. They are not inexpensive. You will also probably want the optional solid lid plate and the cable auxiliary ring as shown in my pictures, that adds about $60 more. 16 M3 heat set inserts (https://www.mcmaster.com/#94180a331/=17gvlmb) A variety of M3 stainless bolts should be used: 12 8mm ones, 4 10mm ones, and 4 12mm ones. You will also need 4 M3 12mm long bolts and nuts to hold the cable roller and the velcro bit to the jackreel. 6 13mm OD 4mm ID stainless steel bearings (https://www.mcmaster.com/#7804k103/=17gvmvh) 2 sections of 16MM OD X 13MM ID (1.5MM wall thickness) stainless steel tubing, cut to length using a tubing cutter and clean up the inside edge to ensure it fits over the bearing. M3 bolts and spacers should be used to mount the fathom board, attach two of the tether wires, and run their respective wires to the fathom board. Everything should print without support. Assembly: 1. Insert heat set inserts everywhere that looks like it needs one, using the pictures as guides. 2. Install the bearings in the cable roller sides first, then insert the longer bolts and last 4 bearings for the main rollers. 3. Cut the rollers to length using a tubing cutter, clean up the inside edge to ensure it fits over the bearing, then bolt the assembly together. 4. Use the upper frame to locate the holes you need to drill in the jack wheel handle and then bolt that on. 5. Repeat that with the velcro cable holder on the other side. For the box, assuming you are using the waterproof version, use the box held flush against the back of the handle so it isn't obstructing the roller to locate and mark the 3 holes for the plastic screws, and then drill a small pilot hole. Then mount the box using 3 screws. Next, drill a 13mm hole in the inside front center hub cover for the slipring. Drill a similar sized hole on the back side of the frame. Screw the slipring adaptor into the center hub using stainless screws in the recessed pocket, and then screw the slipring over it, making sure the spinny around part is inside the reel. Route the static wires into the back box. Now glue or tape the potting guide curved section to the back frame. Install the RCA balun in the box and attach to 2 wires. Now fill that compartment with RTV or clear silicon and secure the lid. Install the 3 potting well lids around the screw holes for the box, making sure to use the one with the cable cutout on the bottom, and then fill those 3 sections with RTV or silicon as well. Fill the potting guide curved section as well. Now, assemble the lid by installing the network cable, optional 2 wire ISBL, and mini usb connectors, and run their respective wires to the fathom board. Mount the fathom board using M3 bolts and spacers, and attach two of the tether wires. When everything is ready to be assembled, run a bead of rtv or silicon around the edge of the box in the gasket groove, then bolt the lid down. Allow to dry for the manufacture recommended duration. Next attach the tether wire to the slipring through the integral spool hole. Fill that hole with silicon. If you have some, add some spare ROV float material into the center drum, then attach the lid with silicon and screws to make it theoretically watertight. The last remaining thing is to finish your tether interface. I used 8 pin Seaconn connectors and this cable support grip (https://www.mcmaster.com/#69675k23/=17gw3j1) along with 3m Scotchcast flexible cable overmold resin to attach the seconn 8 pin micro wetcon section. That allows me to still attach to the kevlar strength member in the ROV cable and tie that directly to structure, but still have a removable tether. There are plenty of other methods as well, so use the connectors and attachments that make sense for you.