NOTE: These are actual working notes so there will be changes as we gather more information and correct mistakes below. There is no shame in skipping to the acknowledgments and photos near the end.
BACKGROUND:
USS Pampanito is a WW II submarine museum and memorial on Fisherman's Wharf in San Francisco. The boat is owned and operated by a non-profit and receives no government operating funds. Our preservation goal is to make the submarine as complete and accurate to our summer 1945 restoration date as possible.
The goal of this project is to stabilize the exterior navigation lights with replica watertight covers and document the system. Secondarily to repair the system.
The lights (except the bow anchor light) have been in operation during recent years after repairs in the 1990s. During 2023 a ground fault grew and was detected by our monitors on the boat (electrical notes). The fault was isolated to the masthead steaming light by turning switches on the navigation light switch panel that is under the helm on the foreward bulkhead of the conning tower. We investigated and found a quart of water in the masthead fixture, and that the cover was a wonky improvisation made from mix of plastic and steel that had failed. The port, starboard, and stern lights all had improvised covers. The bow anchor light has a real cover.
The masthead steaming light lamp base was two wire porcelain (not bakelite), and only held in with one screw. There was a 3-wire flexible cable through a stuffing tube without packing, just electrical tape. Then to a pressure proof plug/jack. Only two screws are holding the light fixture to the bracket. The lamp fixture has an extra flange on the back not found on the other fixtures. The improvised covers have SS-383 JPP stamped on them, JPP is likely the initials of one of the very active volunteers from the 1980s. So our guess is this an early museum era lash up from found parts.
The bow anchor light has not worked in the museum era. A restoration was started but not completed. Its cable has plastic ring terminals in the fixture and its cable is loose under the superstructure and unterminated.
Note the pressure screw on our bow anchor light cover has a 1/4"-20 steel stud on top. Photos of the covers from USS Cod and USS Cobia have either a stud or a hex head screw here. We do not know what these are for, but maybe this was the original location of the tether chain and it was later moved to the dog as an ORDALT to make it easier to turn the pressure screw. Except we have a 1939 USS Sculpin photo with the chain on the dog. Or maybe for securing the cover before installation of the tether chain. We created the threaded hole in the top of our replica screws and filled it with a hex head screw to keep the water out.
When built and during her war patrols Pampanito had a portable bow anchor light that would be mounted on a portable jackstaff. It had a long flexible cable that would plug into a pressure proof jack in the forward escape trunk. At some point, probably at the end of the summer 1945 refit, a fixed mounted bow anchor light was installed on the antenna mast forward. It had a cable going through a protective pipe on the side of the mast (the pipe mounting flanges are still on the mast.)
The aft light was used both as an anchor light and stern running light. Postwar some boats got a second light with a shield to be a 135 degree aft running light.
We do not have any of these drawings:
9-S-4311-L, 13696, stern light and bow light
9-S-5526-L, 9-S-5037-L, 13472m masthead light
9-S-4373-L, 9-S-5526-L side light
9-S-2108-L bow anchor light portable (before fixed antenna mast forward)
9-S-4444-L pressure proof receptacle
The conning tower running light distribution panel is on the forward bulkhead just to starboard of the steering station. Supplied from conning tower box, frame 51 port. Circuits 11FB-102B, 11FB-103B, 15 amp.
- Check for water in all five fixtures after the first serious rain.
- Masthead light. The masthead bracket and shield are rusted with serious wastage. Two bracket bolts have been blown out by rust scale expansion and there is damage to the periscope shear. Only two bolts hold the light fixture. The top (half) step on the periscope shear is welded to the bracket. We need to measure the fixture mounting hole pattern. One of the two lampholder mounting screw holes is full and needs a broken screw extracted. The top and bottom rubber gaskets on the lens are damaged and need to be replaced. We need to find a Fresnel lens that fits. The pressure proof jack and plug should be overhauled. The light now works, but with more ground fault than we want (50k ohms) so it will be left off. This really needs to come down to properly repair the remaining damage.
- Stern light. The original cable supplied from the conning tower RL circuit is cut at the light fixture. It goes through a stuffing tube near the torpedo air charging board on starboard overhead and then to junction box in the overhead. This cable should be replaced and the original supply restored. The fuses are removed in the conning tower.
The active non-historic cable goes under the superstructure and enters the hull at the top of the non-historic stairs. It then loops through the bosun's locker and then to a receptical on the aft (outside) of the locker. So the Starboard S & R (switch and receptacle) switch controls its power.
We need to replace the rusted light fixture foundation welded to the stern chock. Two of the rods between top and bottom of the fixture are missing. Find a Fresnel lens to replace clear lens and replace the lens gaskets top and bottom. The light is operating.
- Bow anchor light. Replace the cover gasket. Replace the rusty threaded rods and nuts with bronze rod. Double nut all the rods with bronze nuts. Prep and paint the steel pieces until we get to this. It has a clear lens that should be a Fresnel lens and fresh lens gaskets. The historic photos show the wire in a long kick pipe that goes into existing flanges on the mast that is no longer in place. The 1944 drawing had a portable bow anchor light with a pressure proof receptacle in the forward torpedo room escape hatch. This was changed to add a permanent installation on the antenna mast forward in 1945. The pressure proof receptacle is still in the escape hatch and wired into the circuit. There is a junction box just outside, port, aft, overhead that has power in and two cables out. One goes directly to escape trunk and receptacle. We need to trace the other two cable to find the through hull stuffing tube used for the lamp fixture, and the cable that goes aft for supply. The cable currently leading from the lamp fixture goes into the superstructure, runs aft and is looped up and not connected near the forward escape hatch. Its path roughly follows an empty wireway overhead similar to one after added for the 5" gun captain sound powered phone. This might have had the running light power, or a calibration sound transducer for the JT sonar. The wireway needs repair and coatings in either case.
- Port running light. Maybe remove old lanyard screw and install ball chain. The original screw to hold the chain is hard to access so this might just stay the way it is.
- External lighting distribution box in conning tower under the steering station has 5 broken cover screws. We started cleaning and penetrating oil on the broken screws and round pivot nuts. Two of the switch handles are the wrong type. The cover and fuse cover should get new gaskets.
- Test and repair the electrical. The forward anchor light is not wired, the port and starboard running and masthead have more ground fault than they should. Aft needs to be restored to its original circuit. We need to clean the old lamp bases, replace the gaskets on the lenses, repack the fixture stuffing tubes. Overhaul the pressure proof plug and jack on the masthead light and replace its gasket. Our experience elsewhere on the boat is that the problems are most often in the fixtures rather than the cable runs. Measure the ground fault contribution after any changes. For now we will leave only the port, starboard, and aft running.
- Figure out where to store the spare cover so it is not lost.
- Not part of this project, but related because they is electrical under the superstructure. We need to refresh the non-historic 1980s deck lights with fresh wire and LED fixtures. Repair the overhead wireway for the 5" gun mount and 20mm gun mount sound powered phones. Repair the overhead wireway that had either the light or sonar cable forward. Remove the remnants of the power for the infrared triggered audio tours.
COMPLETED:
- We removed the bow anchor light cover, test fit it on the starboard running light fixture, then modelled our replicas after it. We made x5 working replicas based on the bow light cover. Our replica cover, dog, and keeper plate are machined from C46400 naval brass instead of cast from bronze. The pressure screw, jam nut, washer, and washer screw are commercial bronze. The keeper plate flat head screws, and the washer that hold the keeper are commercial stainless steel. The tether ball chain is plated brass, and slotted screw is brass. Our replacement gasket is square profile 3/8" N-buna rubber O-ring chord stock (4-7/8" long, glued to 5" O.D.)
When we installed a replica cover (9-S-4311-L) on the masthead steaming light (9-S-5037-L) we found that the flanges on it are just a bit smaller than the bow anchor light or the running side lights that we measured for our replica. We modified the replica to fit.
- Installed new cover gasket and replica covers on masthead, port, starboard and stern lights.
- We cleaned out the debris, then replaced the rotted out lampholder in the masthead light fixture. We rendered some fresh wire, and replaced wraps of plastic electrical tape in the stuffing tube with flax packing. The light works now, but with more ground fault than we want.
- We removed the fuses for the bow anchor light and stern anchor original circuit that are not connected. Replaced one damaged end of conning tower running light junction box cover lanyard.
- We looked to see if any of the switches, wire and lamp bases are set up for dual filament bulbs. Our drawing shows only single filament for SS-383. The port and starboard running light power goes from the distribution box to an unmarked rheostat that is missing its handle and not in the 1944 drawing. The rheostat is bypassed inside the box. The fixtures are two wire. There are no secondary filament switches or cabling setup in the distribution panel. So she only had single filament bulbs.
ACKNOWLEDGMENTS - THANK YOU!
We appreciate the advice, help, donations, discounted products, and services from individuals and companies that make our restoration projects possible. We can not succeed restoring Pampanito without the incredible generosity of these people and companies:
Similar light on USS Sculpin in 1939. Note the Fresnel lens. It looks like there is a stud on the pressure screw.
July 1945 image showing changes to the boat at the end of overhaul. It shows a pipe with cable leading up. Maybe a horizontal foundation on top to hold the anchor light.
November 1945 image that might show the light installed but hard to tell.
Jan 1946 image that might show the light installed, but maybe something on the boat Pampanito is moored next to.
1960 The bow anchor light fixture is clearly in place.
1981 the bow anchor light was installed with wire through the long kick pipe.
Mid-1980s the bow anchor and masthead lights were operating.
Bow anchor light as found 2023. There should be bronze double nuts on the rods between top and bottom. Three of the rods are steel instead bronze. It has normal glass, not a fresnel lens. There are plastic insulated crimp terminals so this has been repaired post war. There is a stud in the top of the pressure screw, but it is steel not bronze. Below this the pipe to protect the cable is missing.
Bow anchor light cover. This is the only real cover on the boat. To install the pressure screw with jam nut is turned out from the dog. This brings the cover plate and the dog together. Once inserted with the cover plate on the fixture gasket, the dog is rotated under the flanges on the fixture and the pressure screw is tightened. It just needs to be tight enough for a little compression of the gasket. Once the pressure screw is tight, the jam nut is turned onto the dog to preven the pressure screw from vibrating loose.
To separate the dog from the cover plate, insert a screwdriver through the hole in the dog to access the four flat head screws on the capture plate.
Dog assembly separated from the cover plate.
Masthead light after a quart of water was removed. Cover chain was not attached to the screw provided for it. The flanges that hold the cover are narrower than the fixtures. The bottom has the big mounting flange (pipe like thing on the back) that is not on the other fixtures.
Masthead lampholder and wire is corroded, and the lampholder has only one mounting screw. Replica gasket is installed.
This is the improvised cover found on the masthead light. The steel cover plate has a large hole in the center so the plastic plate below was needed to keep the water out. The new cotter pin was inserted where a rusted pin that disintegrated in our fingers during disassembly.
Masthead light showing shield and bracket. Only the the masthead light and the searchlight have pressure proof plugs and jacks in the supply cables.
Masthead light bracket is rotted out on port side, and has two of four bolts blown out by rust scale expansion. There is damage to the periscope shears.
The port and starboard running lights had similar improvised steel covers to the masthead light, but without the plastic plate so they had no watertight integrity at all. These are mounted with the cover hole on the bottom so they did not fill with water, but it allowed moisture in the fixture.
Stern anchor light as found. Note the improvised cover, two missing rods between top and bottom, missing double nuts, cut original wire, small diameter supply wire, wrong chain mount, regular instead of fresnel lens. It used a smaller diameter gasket.
The aft anchor light foundation welded to the stern chock is badly rusted. Rust scale expansion has broken two of four mounting bolts.
Three of the five replica cover parts ready for assembly.
Three of the five replica covers and gaskets before installation.
Masthead light with replica cover, gasket, and chain installed. The wire and lampholder still need to be repaired, but the fixture should stay dry. Note the flanges that hold the dog are narrower, and lower than on the other four fixtures. We shaved down our replica dog on the ends to fit.
Starboard running light with replica cover and tether chain installed correctly.
Port running light with replica cover installed. We had trouble reaching and removing the tether chain mounting screw on the fixture so we attached the chain that was on the previous cover.
Stern light with replica cover and chain.
The running light distribution panel is next to the steering station on the forward bulkhead of the conning tower. The red arrow points to the port and starboard light rheostat. The rheostat has been bypassed in the box.
The bow anchor light junction box in the forward torpedo room, overhead, port, aft right next to the escape hatch. Circuit RL, one cable marked Running Light. One cable goes over to starboard, then aft to supply power. One cable goes directly to the pressure proof plug through a stuffing tube in the escape hatch. The last one goes over to starboard and should be going to a stuffing tube through the hull we have not found yet. We need to trace the cable.
Pressure proof jack for portable bow anchor light in the escape trunk.
The stern anchor light junction box in the aft torpedo room, on starboard just above the torpedo air charging equipment. Labeled R.L. The stuffing tube out of the pressure hull is a short, exposed, easy to follow cable run from the junction box. Outside the hull the cable runs to the stern chock and is cut at the light fixture.
The non-historic cable powering the aft light ends at this receptacle. It is aft of the bosun's locker. Its switch and fuse are in the lighting distribution panel on the forward bulkhead labeled, "S & R'S ST'B'D."
