Here are some photos of the interior of Matthew's USS Wichita.  It started out as a Swampy Brooklyn kit (5 triple 6" turrets), but in order to more easily install dual sterns I changed it the a close sister ship (same hull), the USS Wichita, which had 3 triple 8" turrets).  This is that same ship whose vacuum formed superstructure is detailed in the Vacuum Former construction article.  I thus threw away all of Swampy's nice superstructure pieces!  I did get in return, though, a ship that is not just another Brooklyn!  Of course seeing as I vacuum formed the decks and splinter shields as a single part, I did not have to build them up from plastic strips either, and the Brooklyn and Wichita both have lots of splinter shields!

Figure 1

    This is the bow showing the forked mount which holds the regulator.  The fork fits in the narrowed section of a Swampworks Light Regulator.   The gray blob at the base of the regulator support is a fillet of epoxy plumbers putty, used to reinforce the joint.  The fiberglass hull was rough sanded in this area to give the putty some "bite".  All the bulkheads are similarly reinforced.

      The black area is a piece of foam, used to prevent water from building up in this dead area.  It also adds a little buoyancy to help insure that the hull angles down a little toward the pump in the stern, as the water builds up due to damage.

    Note the cross piece to hold the subdeck to the proper width.  This is a piece of 1/4" X 1/2" basswood strip.  Secured with superglue and pined with a dowel at each end.  The subdeck strips started as 1/4" X 1/4" strips that were fitted using the technique in the Reliable Construction section.  The piece at the end of the bow is 1/4" ply with notches cut for the strips to key into.  The ends of the strips are also pined to this plywood section.  The entire subdeck was assembled and tack glued to the bottom of the finish deck before the fitting process was done.

    At the right of Figure 1 is the radio box (shown in Figure 2 below), with the receiver switch mounted (black piece, shown also in Figures 2 and 7).

    You can see that I added two lead fishing weights at the extreme bow.  I found during bath tub tests that adding this weight in the bow actually increased the amount (about double!) of water that the ship can take on before sinking!!  As with most ships, she tended to sink by the stern, and the extra bow weight counteracted this.  The bow rides a little lower (but not that much), but the water all still reaches the pump in the stern.

Figure 2

    Figure 2 shows the radio box.  The box itself is a Swampworks small radio box.  The lid is sealed with waterproof radio box tape, available at most R/C hobby shops.  The wires are sealed with thick superglue were they enter the box, and the receiver switch (right) is mounted outside the box, on the lip.

    Inside the box are (from right to left) the receiver filter circuit (described in the Receiver and Solenoid Wiring section), receiver, the throttle servo and switches, and the gun poppet servo and valve (with actuator arm).  The antenna wire exits the right side of the box and all power wiring enters on the left (with all the heavy current power wires not going past the throttle area).  This helps isolate the receiver from motor noise.

    Look closely at the gun servo disk and you will see the the area that the actuator arm rests on is almost at right angles to the disk movement.  With just a little servo movement the valve goes from fully closed to fully open.  the servo can thus fire more rapidly than if it had to move a significant amount of its' full range, and then return to neutral, before firing again.  This servo fires the dual stern guns via an MAV-3 valve and pilot actuators attached to the MAV-2 valves that actually operate the guns.  The MAV-3 is mounted with a customized MAV-2 valve body.  I'll describe the general modifications further down in this page.

Figure 3

    Figure 3 shows the battery compartment (right), pump, gas shutoff valves for the guns (one for each of the two gun poppets), drive motors and the interior end of the prop shafts.

    The battery is held in place by the block on the right and the bulkhead next to the pump.  There is a block not visible under the wires in the battery area (bottom of photo), that displaces the battery toward the top of the picture.  Gell Cell batteries have an airspace at the terminal end, and this displacement (the terminals are at the top of the photo when the battery is installed), balances the battery at the hull centerline.  The connectors are all the Tymia(sp) type available at hobby shops.  The ones pictured are the style that comes with the contacts not installed, you attach the wires and then push the connectors into the housing.

    The pump is a modified old style Swampworks model (scratch built, but following the general design).  It is attached to the adjoining bulkhead with a bead of thick superglue.  The pump and drive motors are the small type that H&R used to sell.  They are held in place with SS sheet metal screws in the two punched holes in the end of the case, at the shaft end.  The screws cut their own threads when installed.  The pump outlet is at the bottom center of the picture.  There is a piece of 1/16" ply attached to the inside of the subdeck to secure the copper piece.  The copper piece also rests against, and is glued to, the bottom of the subdeck.

    The drive motors are installed in custom holes drilled in the bulkhead.  Not visible is a sheet of thin fiberglass circuit board on the side of the bulkhead away from the motors.  This sheet acts as a hard surface/washer to keep the screws from gouging the bulkhead surface as the motors are changed over the years.  You can see that the interior ends of the propshafts are also supported by a bulkhead.  The propshafts themselves are the standard design Swampworks style and the two blocks with the brass screws are the lubrication points (when screws are removed).  The thin brass rods are the outer dummy shafts (small to save weight).  They are also supported on the inside by the bulkhead.  All the bulkheads, of course, have the bottoms cutout for free water flow.

    The gray wire is the twisted shielded wire for the rudder servo.  I got it at Radio Shack.   The reason for and wiring of this line is also described in the Reliable Construction section.

    All the CO2 gas lines have couplers used so that the guns (and the stern deck they are attached to) can be removed for service.  The "T" fitting by the motors splits the single control line from the gun servo to the two pilot actuators that drive the MAV-2 gun poppets.

    The two holes in the rim are for the #3 deck hold down screws.  At the bottom of the holes are matching "T" nuts, secured with thin superglue.  On this ship the stern deck (and thus the guns) are semi-permantly installed, and the deck is normally never removed during an event.  All battery, CO2, and BB fill service can be done with just the forward deck removed.  The forward deck is held in place with a notched block that slips under the bow 1/4" ply subdeck piece, and two hold down latches close to where the forward and stern deck pieces meet.

Figure 4

    Figure 4 shows the rudder servo box and the rudder gears.  The rudder box is a Radio Shack circuit box, with a clear window RTV'd over a drilled hole.  This window will fog up if any moisture gets into the box.  The servo is mounted on its' side.  The servo is mounted on a 1/16" vertical ply bulkhead that slips in two of the grooves built into the box for holding circuit boards.  A standard rubber boot seals the control rod as it leaves the box.  The servo was installed and the rod adjusted, then an RTV bead was run around the rim of the box, and the top installed.  The next day I ran another bead around the outside of the joint and the tops of the screws were also sealed with a drop of RTV, as is the rudder servo wire.

    The box is held in place with a tight slip fit between the basswood strip by the shaft lube blocks and a rear bulkhead barely visible at the rear of the box.  The bulkhead and strip are not sealed, and the swelling caused by a little water in the hull locks the box in more securely than you would think.

    Again a ply section is used at the stern, with the subdeck stringers notched and dowel pined in.

Figure 5

    Figure 5 shows a close up of the rudder gear assembly.  This one is much more complex than is strictly needed, but allows the entire assembly to be removed as a unit.  There are two crossbars that hold and locate the two shafts.  The bottom one is visible, but the upper one is covered by the gears.  The large gear shaft fits into the right vertical tubing, and the bottom end of the shaft fits into a short section of matching tubing drilled and secured in the bottom of the hull (in the same manner as the rudder shaft housing.  This tubing locates the forward shaft.  Visible at the bottom of the large gear shaft is the collar that the rudder throw arm is soldered to.  This collar rides on the top of the front locating tube.  The rear tubing slides down over the rudder shaft housing tube.

    To reinforce the joint between the plastic gears and their shafts brass plated were soldered to the collars and #2 screws and bolts, drilled through the plates and gears hold them together.

    The plastic gears came from a caterpillar looking segmented toy truck of my son's, that was declared "Broken".  I got about 10 or 12 gear set pairs like those shown from the toy.  I drilled the shaft holes on my lathe to insure concentric running, then promptly bent the collar plate assembly on the larger gear trying to face it for better appearance!!  I managed to get it bent back close, but was too lazy to make another assembly.  It works all right as long as the gears are positioned to limit travel to the section of the gears that mate the best.

Figure 6

    The bottom of the water tight radio box is shown in figure 6,  The screws attach the wood stringers that the servos are attached to.  They are SS sheetmetal screws, similar to, but a larger size than, the motor mounting ones.  They are sealed with several applications of thin superglue to the outside joint.

    The MAV-3 gun poppet and its' modified MAV-2 mount are shown clearly here.  The MAV-3 is a vented valve, with the vent in the end of the valve stem.  This vented type valve is needed so that the pilot actuators can release at the end of a firing sequence.  With an MAV-2 non vented type the pilot would stay depressed after the first shot, as there is no escape path for the CO2 when the valve closes.  The problem with the MAV-3, however, is that the valve stem hole would vent into the radio box if normally mounted!!  Not so good for keeping the top attached!!!

    To solve this I disassembled an MAV-2 and drilled and taped the location where the original valve mechanism was to fit the MAV-3 mounting threads.  Actually I drilled and taped it for a standard 7/16 NC thread, and turned down and die cut the MAV-3's odd 15/32-32 thread to match.  The original MAV-2 stem (with its' O-ring seal) is reinstalled and then the MAV-3 screwed in until the MAV-2 stem contacts the MAV-3 stem.  The MAV-2/MAV-3 combination is then installed like a regular poppet.  The MAV-3 now vents out the MAV-2s original gas outlet, and the MAV-2 stem O-ring prevents gas entry into the box.  A short length of hose is installed in the MAV-2 outlet to help prevent water entry should the ship sink.   To insure that the MAV-2 O-ring does not back out, it is removed, cleaned, a SMALL drop of thin super glue is placed in the O-ring seat, and the O-ring reinstalled.  After the glue sets overnight, the O-ring was relubed with some petroleum jelly on the end of the cotton swab.  This combination adds a little extra drag on the servo, but neither the servo or MAV-3 return spring have been adversely affected, nor has the valve return been noticeably slowed.

    Placing the gun servo outside the box and waterproofing it, is the standard way of handling this, but I prefer my servos in a box!!

Figure 7

    The receiver switch mount is shown in figure 7.  Rather than having a hole in the lid, I mounted it on the rim of the radio box and ran the wires out to it.  I mount my switches on all my ships in this vertical arraignment, with the switch being ON with the shaft pushed down.  This setup makes it almost impossible for a BB hit to turn the switch OFF.

    The antenna wire (white) does not normally run past the switch, but fell into this position during setting up for the shot.

Figure 8

    The propshafts shown in figure 8 are standard Swampy, except for the supports.  In the past on my other wood frame ships I soldered the support to shaft joint after everything was installed and positioned, but doing this to supports in a fiberglass hull is not recommended!!  The supports shown are soldered the the brass tubing collars before installation, then the shafts are slid through the tubing before they, and the support rods, are permanently epoxied to the hull.  Much easier!!, and it allows for a lot of adjustment possibilities.  The making of the support rod/collar assemblies is also detailed in the Reliable Construction section.

    As can be seen, I cut the tips off of the prop hubs to allow the rudder more swing, without interference.  The rudder gears give the rudder about a 170 degree swing.  Close observers will note that the ends of the propshaft housings are thinner than the rest of the housing.  As the kit arrived it had a balanced rudder (rudder shaft in the middle rather than the end).  After installing the shafts and the rudder post I decided to switch the the rudder shown.  I extended the prop shaft to bring the props close to the rudder, and added a length of the next two sizes of tubing to reinforce the extra length.

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