This article may be copied and distributed freely with the following restrictions: No one may claim it as their own work, and no profit may be made off it without my knowledge and permission. Anyone wishing to use it as part of a Web Page may do so as long as the above restrictions are not violated and the restrictions are clearly stated in reference to them.

I.    MOCKUPS

    The best way to resolve a point of confusion on a set of plans is to build a mockup. For example, when I built the Arizona the hull lines on the plans overlapped and ran very close in several areas. This was especially true in the upper hull area above the torpedo blister. The discontinuity caused by the blister made relating the upper lines to the lower impossible and not all the lines were labeled. In fact the plans were in error in that the hull lines did not even show the stern casements! Rather than cut expensive plywood on guesses, I built a 1/196 scale half breadth mockup. A half breadth model is a model of the hull from the centerline out, mounted on a board like a bas-relief. You may have seen one if you have ever visited a maritime museum. I used 1/16th balsa and cut out each frame with scissors. I glued a hull outline on a board and using a cheap triangle, as a guide, glued each frame in place vertically. I then glued the deck on. This reveled several errors both in the plans, and my interpretation of them. It only took two evenings and I spent about $5.00 on balsa and reduced size copies at the library. This saved me countless hours in the construction time. It could also have been the start of a unique model to hang on a wall.

    Foam board is another good prototyping material. This is a foam core with cardstock laminated on either side. The board is available in several thicknesses, with 1/4 inch the most useful for us. On the Arizona I used it to mock up several ribs in the stern to aid in determining the propshaft locations. I mounted a prop on a brass tube and stuck it through the foam. I then disassembled the mock up and used the punched holes to mark my real ribs for the shaft holes. When the hull was assembled everything lined up! To model superstructure areas I cut out and stack foamboard, wrapped once with tape, to simulate the deckhouses, and use cardstock for the decks. This is especially useful to verify the accuracy of the deck penetrations for the masts and tripods. Again a couple nights spent making a mockup can save you days of frustration with more expensive materials.

II.    NOTES ON MATERIAL SELECTION

    Use noncorroding materials where possible. Do not use plain steel anywhere if at all possible. The most common use of steel is for screws. Many hardware stores carry stainless steel screws in the common sizes for just a little higher cost. If you can not find any in your size try to use galvanized screws. The #2, #3, and #4 sizes from DUBRO are galvanized. Replace exposed screws of the galvanized type every year. Another major use of plain steel screws is for the setscrews in the props and collars. Stainless steel setscrews are also available for these from many sources. You may have to buy $25 worth if mail ordering, so see if you can get several friends in on the deal.

    The other major plain steel source is the shafts on our motors. They may look like SS but most are plated. The most common motor failure is in the area where the shaft contacts the bearing. The shaft rusts due to trapped moisture. This causes the bearing to wear rapidly or seize on shaft. The only way to combat this is regular oiling. The motor cleaning/lube sprays available for RC cars are good bets. Pump motors are the most susceptible as this bearing is generally unreachable. A failed or failing motor bearing typically will produce a loud squealing sound. I always carry at least a spare pump motor, just in case of rust or meltdown.

    Most of the props and collars we use are brass and a steel or even SS setscrew can seize in the threads. If you try to force the screw out you risk stripping either the threads in the brass or the hex socket in the setscrew. If the setscrew socket is stripped you have to try to drill out the setscrew and use an Eazy-out to remove it. To avoid this and also ensure that the setscrew does not vibrate loose, use a thread locking compound such as Lock-Tite. This not only prevents the loosening of the screw but also seals the tread area to prevent rusting. Use only the standard strength (blue) or you may never be able to remove the screws. The higher strength (red) can, however, be useful when assembling pieces like the CO2 manifold that you typically would not be disassembling once it is built.

III.    SCRIBED DECKS AND DECK FINISHES

    For a good looking deck, planking lines can not be beat. A gray painted deck is also prototypical and simple, but everyone thinks of planking associated with decks. As a guide if plans are not clear: In the smaller ships, some light cruisers and smaller, the decks had no planking. In larger ships generally only the main weather deck and the next level were planked. This was for limited shell protection, insulation of the living spaces, and appearance. There are three ways to simulate the planking. The first is to lay individual planks or lay commercial scribed planking. This gives a fantastic look, but is time consuming and the decking almost always buckles after a few trips to the bottom. The second is to draw on the planking lines. This looks good, but be careful to apply the finish without smearing the lines. The third way, and my choice, is to scribe the lines into the deck.

    The scribing is not as difficult as you might think. I generally scribe the lines about 3/32" apart. This simulates planks about a foot wide. This is wider than prototypical, but still looks good without investing days of time. It also saves on my aging eyes. I lay out the future lines on the shaped & sanded deck, before any parts are attached. To do this I mark a series of dots 3/32 apart widthwise from a center line, about every 10 inches lengthwise. Using the ruler portion of my adjustable square I scribe the lines using the tip of a razor saw. Three medium pressure passes for each section of line, cutting into the previously completed section, will be sufficient. If you should misscribe a line just be careful to scribe in the proper line from the opposite end. The mistake will virtually disappear after finishing, IF dirt or other material is kept out of the mistake. To save time and effort lightly mark the superstructure areas and only scribe enough to be sure that the deckhouses will cover the ends of the lines. When you are done, sand the deck lightly to smooth it. Run a #2 pencil down the scribed grooves to highlight them and sand again.

    The lines would be made extremely difficult to draw if done after the superstructure and turrets were attached. However, if you do them before this, how do you protect them from smudging or damage? If you use a standard finish then you will be gluing the superstructure parts onto the finish not the wood! The solution is to scribe/draw the lines then finish with superglue! Yes, superglue! This produces a durable finish that you can glue to. Use one of the standard thin superglues. Do not use the odorless glues as they seem to be less water resistant then the regular ones. I have two ships using this method, the ship using regular glue has held up for 9 years, the one with odorless glue started to show miner delamination at the scribe marks after about 3. Use a 3X5 card or cut a piece of cardboard as a spreader. Squirt some glue on the deck and spread it with the card. As the glue runs out add more. Try to go over the surface parallel to the deck lines and with as few swipes as possible to reduce any smudging. Wipe some glue on the edges as you proceed down the deck. Let the deck air dry overnight. Do not hit it with kicker, this will give rough and/or frosted finish. Do this in a well-ventilated room, the fumes from this much glue are intense. The next night give it a second coat. Much less glue will be required this time. After this give the underside a couple coats, being careful to not have any run over to the finished side. This process will take the better part of a large bottle of glue, but the time it will save later and the clean, smudge and dirt free, deck it produces is worth it.

IV.    DECK RIMS

    I do not like to expose the raw plywood edge of the deck to BB fire. It can easily be split by a hit on the edge. I use a 1/8" X 1/4" basswood rim. The finish deck is trimmed back from the hull edge a little less than 1/4" on each side (so that the basswood strip will stick past the subdeck rim, and can then be sanded to match the hull lines). The basswood is soaked several days to make it pliable. The basswood is then laid down with the 1/4" side against the subdeck, and the 1/8" side up against the installed deck, which is also 1/8" thick, and secured until dry (Figure 1). The basswood will then retain its new shape. After it is dry the deck is protected with wax paper and the basswood is glued in place. After the glue sets the outside is sanded flush. The deck will be a tight fit and should any damage be done to the basswood it can easily be patched. For casemated areas use a wider piece of basswood and use it to form the complex shapes of the deck rim. Figure 2 shows this method used for one of the stern casemated areas on my USS Arizona.

                                            Figure 1                                                    Figure 2

    With a fiberglass hull, you can use the hull as the deck rim, or fit the subdeck flush with the hull, and fit basswood strips as above.

V.    FITTING THE FINISH AND SUBDECKS TO A FIBERGLASS HULL

  I prefer to use a 1/4" subdeck with a rim about 3/8" to 1/2" wide with a 1/8" finish deck. With a wooden framed ship this is no problem. With a premade fiberglass hull how do you install the subdeck? First cut the finished deck to outline (if not already supplied). Draw the centerline down the length of the deck. Lay the deck carefully in the hull and pull the hull up against the deck with masking tape that spans the top. A fiberglass hull tends to spread apart a little widthwise as it sits and this pulls it into shape. For this operation an end of the deck can overhang slightly allowing for final adjustment later. Most hulls are vertical where the deck meets the hull in the middle of the ship. We are concerned with the bow and stern areas where the deck angles off of vertical. In these areas draw lines 1" apart, perpendicular to the centerline the full width of the deck. At the extreme bow and stern they may need to be 1/2" apart. Number the marks and make a table of them on a piece of paper. Transfer the marks to the hull sides and number them the same. Carefully slide the deck out from under the tape, leaving the hull open and the tape holding the hull in the right shape. Absolute precision is not required.

    Take a piece of basswood or hard balsa 2 to 3 inches longer than the maximum width of your ship glue a piece of wood projecting down at a right angle to the edge of the first piece (Figure 3). This piece should project down the distance from the hull edge to the desired bottom of the subdeck (measurement B in Figure 3). Inset it from the end about two inches. Using this tool placed crosswise record the distance the hull sets in at the bottom of the projection to the inside edge, at each mark (measurement A in Figure 3). Be sure that the projecting wood touches the hull in line with the mark. Record for both sides, they may differ. Also use this tool held along the centerline to record the extreme bow and stern insets.

Figure 3

    Cut the subdeck to the same outline as the deck. Cut out the inside access opening(s). If the deck will be inset even with the hull edge, tack glue the subdeck to the bottom of the upper deck. Mark the bottom of the subdeck to the same increments as you did the hull. Transfer the recorded distances to the subdeck. Be sure to remember which side is which on the upside-down deck! Draw a curve freehand between the marked points. This marks the inside rim of the bottom of the subdeck. Figure 4 shows the marked subdeck (bottom side up in this drawing). Carefully sand from this line on the bottom of the subdeck to the top rim (Figure 5). If you are insetting the upper deck into the fiberglass hull sand to the top of this deck. Be careful when sanding the finish deck that you do not change the shape at the top of the deck.  If you do you will have gaps between the finish deck and the hull when finished! This will give you a fairly good overall fit. Trial fit the deck/subdeck to the hull and sand the assembly to final fit. Do not worry about minor gaps.

Figure 4

Figure 5

    If you earlier tacked the subdeck to the deck, separate them now. Sand the hull in the area where the subdeck will attach to provide a good bonding surface. Tack glue the subdeck into position about every 8 to 12 inches with superglue. If you are going to set the finished deck even with the hull, use a piece of scrap as a guide for getting the subdeck down to the right level. Mix a batch or fiberglass resin and flow this into the joint between the deck and the hull using a cheap brush. You may want to mask the outside of the hull with a rim of tape stuck to the hull and projecting above the hull top. This will provide both a drip catcher and a guide to run the brush against. If possible coat the top and bottom surfaces of the subdeck at the same time to seal them. After a few minutes when the fiberglass has begun to set run a piece of scrap along the top of the joint to remove any buildup from the corner. Also clean up any large drips. Set the ship aside in an upright and level position. After the fiberglass has gelled, but before it has hardened, apply another coat to the joint. As the first coat sets some will have run out of the joint. Clean up the corners as described above. Remove the tape when practical to prevent the adhesive from becoming a permanent part of the ship. If the subdeck was set below the hull rim sand a chamfer around the bottom of the finish deck. Some buildup in the corner is inevitable, and this will provide clearance.

VI.    GETTING THIN FIBERGLASS SECTIONS TO SET

    Fiberglass has many uses in our hobby. It is used both as a standalone hull material and to add reinforcement and waterproofing to wooden hull framework and watertight boxes. It can also be used to form turret and superstructure pieces. In the thin sections we use, however, a problem arises. The chemical reaction between the resin and the hardener depends on the heat created by the reaction to work. With thin sections heat is lost rapidly and the fiberglass may take days to fully set, if ever. I have found a way to solve this problem. "Bake" the fiberglass! No not in the oven, but in the back of your car. Protect the seats and lay the mostly set assembly where the sun can shine on it. Close the windows and park in the sun. Go out a few times daily and reposition the ship to keep it in the sun and expose new sections as the old ones harden. The surface will get quite warm even on a mild winter day. It may take a couple days but the fiberglass will setup. Be aware that you will have to air out the car each time you wish to drive it!

VII.    SUPERSTRUCTURE CONSTRUCTION

    The superstructure on our ships has the unique requirement of being bullet proof. Of course, so does the builder's attitude. Build strong and only as detailed as you are willing to see fly off the ship on occasion. I prefer to use close cell foam for the deckhouses and plastic sheet for the "nonplanked" decks and splinter shields. Look in the phonebook for sources for the foam. I bought a lifetime supply for about $30.

Figure 6

    For the decks I use either 0.040" or 0.060" thick plastic built up assemblies or 0.020" thick vacuum formed pieces (see the Vacuum Former section for details).  Figure 6 shows a picture of the foam block and vacuum formed decks used on the USS Wichita.  For built up decks I use liquid plastic glue, not the tube cement, and then reinforce the joints with a bead of thick superglue. Be careful that you use a kicker that does not attack plastic.

    The foam for the deckhouses is laminated with superglue if it is not thick enough and then cut to shape with a razor saw. The deckhouse is attached with thick superglue. Sketching the deckhouse outline on the deck or lightly centerpunching opposite corners when laying out the deck helps in placement. Also if there is a mast going through the deckhouses drill the holes carefully before assembly and use a temporary mast as a guide to aligning the pieces. This brings up another tip. Always drill a hole for the base of the masts to fit into the deck, this greatly strengthens the assembly. I have had good service with using hardwood dowels for masts. The dowels are lighter than brass, glue better, and do not dent like brass or aluminum. I have on occasion had a small chunk knocked out but never a dowel broken. To paint the superstructure I use plastic model paint and give the deckhouses three to four coats. The foam is similar to wood, in that it will absorb a lot of the first and second coat. Let the assembly dry about 24 hours between coats so that the paint absorbed by the foam will thoroughly dry. Using the above methods I have not had to do any major superstructure repair in 5 years.

VIII.    PVC FOR BARBETTS AND TURRETS

    For your barbettes and rounded turrets use PVC pipe to build them.  See the barbetts for the forward turrets in Figure 6 above, as an example. There is generally a pipe or fitting size close to the barbette dimensions and you could not ask for a more BB proof assembly. If you have access to a lathe turn a shallow shoulder on the base and insert the barbette through the deck up to the shoulder. This produces an extremely strong joint. The PVC pipe is well suited to those who delve into rotating turrets. A pipe union filed or bored out to a sliding fit on a pipe makes a perfect bearing when used as a barbette. Alternately a pipe with a turned down, on a lathe, union from the next smaller size pipe can be used.

    For a rounded turret I will use my Arizona as an example. The turret shape was basically a tube with three sides sliced off at an angle vertically, with an overhang projecting off the back. This lent to easy construction. I made the barbette out of a straight connection that I bored out, on a friend's lathe, to a slip fit on the pipe. I turned a shoulder on the deck end. I cut a length of pipe longer than needed. Then I temporarily glued a, turret height, length of union to one end. This was the start of the turret. I then made an angled cut on each of the three sides. The back was left uncut. The former union piece was then freed and the sides were covered with 1/8" plywood, sanded flush with the PVC. A properly shaped top was then attached and a block of foam formed the overhang on the back. A #4 screw and T-nut are used to hold the turret to the cut pipe, which due to the angle cut has a positive interlock with the turret. This formed a strong bullet-proof assembly that is easily removed for service and lends itself perfectly to a rotating turret.

IX.    PVC ACCUMULATOR TANKS

    While PVC can be used to make a light weight low pressure (less than 200 psi) accumulator tank, it does not hold a thread well. Drill out a brass screw to accept the fitting with the hole extending the length of the screw. Drill and tap the PVC cap for the screw, install the screw with the head flush with the outside of the cap, and back it up with a brass nut on the inside. After all the screw attachments have been fitted, glue the PVC tank together. The brass nuts should be secured with superglue or a thread locking compound.

X.    REINFORCING WOODEN JOINTS

    The most likely failure point on our ships is the butt joints in the wood. An example is where a rib meets the deck rim. Superglue is strong, but a joint like this can apply a lot of leverage on a small area. A good solution is to use Tree-nails to strengthen the joint. A tree-nail is simply a small wooden dowel that is glued into a hole drilled in the joint after the original joint has set. Before the advent of cheep nails, the tree-nail was the chief method of attaching two pieces of wood. The wood dowel expands and contracts at the same rate as the wood in the joint and is flexible. Screws or nails could be used, but they corrode , are heavy, and can lead to cracking of the wood as it swells and flexes. I use 1/16" dowels I obtained at a hobby shop. The hole should be a tight fit to the dowel.

    A deck rim to rib joint would be reinforced in the following manner. Drill vertically through the deck into the end of the rib. Squirt some thin superglue in, drive in a length of dowel, and let it set overnight (Figure 7). Do not use kicker! The next day cut the protruding dowel off flush and soak the end with more thin superglue. After this sits for several minutes you can hit it with kicker.

Figure 7

    The next area to visit is the all important PUMP! You were planning to stay dry, right? First be sure that the impeller does not hit anywhere in the case. If it hits even a little I guaranty that it will lockup at a critical time. The smallest piece of debris can easily become lodged in the tight spot. If you think everything is fine run the pump and listen closely for interference.

    Try to minimize any dead space between the top of the impeller and the case. This space will only be filled by uselessly spinning water and the larger the space the longer the pump will take to fill with enough water to prime. Any air trapped in this space can also cause the pump to cavitate preventing the pump from fully priming.

    Every pump should have a vent hole to allow trapped air to escape. This vent hole is critical, but care should be taken in its size and placement. The vent hole will also "vent" water once the pump starts working, so do not make it too large. The best places for the vent are through the side at the top of the pump cavity and around the motor shaft. If your case is one solid piece the vent hole can be made large enough so that you can use it for access to the setscrew. Simply glue a cover over most of the opening once the pump is assembled. If you have a pump case that disassembles to allow access to the impeller while it is still on the shaft, try the following idea. Use a triangular file to file two grooves in the hole the motor mounts through. Place the grooves so that the water will squirt on the case, not directly through the motor. Then when you attach the motor place a couple of thin washers on the screws between the motor and case, rather than mounting it flush. The water will splash into the motor helping to cool it, and the case will somewhat impede the flow reducing vent loss. Try to leave the vent hole some other shape than round to decrease the chance of capillary action holding water in the vent.

    Use adequate screening to protect from debris. You should have a piece covering the inlet hole AND an additional screen covering the entire base (feet, screws, and sides). The inner screen keeps debris from entering the case. The outer keeps debris buildup from preventing water reaching the inlet. You do need both! I used to have only the inlet screen until I sank twice in one day, with little damage, due to the same debris lodged invisibly under the pump, cutting off water flow. I realized what caused the first sink and thought I had removed all the crud the first time.

    For the pump case outlet use a piece of 3/8 brass or copper tubing. For a straight outlet use the brass as it has a larger inside diameter. If you are going to bend the outlet 90 deg to come out at a more useful position use the copper. Use as wide a bend as possible in the plastic tubing from the pump outlet to the restrictor fitting. Sink test your ship, if possible, before selecting the position of the restrictor. The ship will tend to roll to one side consistently as it fills. Place the restrictor in such a manner that the water stream will contract this roll. This will help your ship to stay up what may be those last critical seconds.

    Try to leave space so you can mount the pump in either the bow or stern. After you have a few sinks under your belt you will better be able to decide which placement would be best. To start with place it in the stern. Most ships sink by the stern and as your ship runs forward the water runs to the stern, so this placement works well. If space does not permit stern placement try to build the ship a little bow heavy and place the pump in the bow.

XII.    WATER CHANNELING

    The inside bottom of your ship should be built so as to channel the water towards the center and in the direction of the pump. This is critical for flat bottomed wide hulls! If the water is allowed to flow to one side the ship will list to that side and the water will stay there. With the water to one side it obviously is not going to reach the pump. The ship will quickly roll over and sink. I have used the same foam as for the superstructure to make blocks to fill in either side of the hull on wide ships. These not only force the water to the center but add flotation to the listing side. In the same line if the water is in the center, but there is a battery or box blocking its flow to the pump, you are going swimming. Place the boxes and batteries up on 1/4 inch risers glued to the bottom of the hull. This has the added advantage of allowing you to get your fingers under the equipment to remove it. You can also use the spray in foam sold in hardware stores to fill in isolated areas, such as the extreme bow. The fumeless superglues will not attack this and can be used to seal the surface. Be careful when using these foams as they expand a great deal! One Captain (no not me) found this out the hard way when he came back a little while after using this foam to find his hull completely filled with the expanding foam. He also discovered that you should let the foam completely set before trying to remove any excess. He ended up with a hull coated inside with a sticky hard to remove goo! Several years later he still gets occasional ribbing about that one! Do not overdue the use of foam or other flotation material low down in the hull. It will try to float on top of any water in the hull and can lead to capsizing.

XIII.    PROPSHAFT STRUTS

    I build the ribs (wood frame) or mounting plates (fiberglass hull) such that the prop shafts can be slid in from the outside through minimal holes in the hull. The inside end of the shaft is supported by a rib or plate. This provides a solid support for the shafts. This provides solid durable service, but does entail one difficulty. The outer shaft strut cannot be attached to the shaft permanently and still itself be pressed into the hull. On my wood ribbed ships this was not a big problem, I simply carefully soldered the joint with a torch after the assemblies were installed. The wood got a little scorched, but that was all. However, when I started on my first fiberglass hull this was not an option! I came up with the following method. I made struts that slipped over the propshaft housings (Figure 8A). These are pressed into the hull and the shafts are slid through them into the hull. When everything is lined up the shafts and struts are glued solid at the hull interface. The joint between the housing and strut is left free to allow for hull flexing and movement.

Figure 8

    The slip rings are made in the following way (see Figure 8). Take two tubes the next two sizes larger than the propshaft housings, long enough to make all the required struts (and maybe a few spares), and solder them together (Figure 8B). These will be for the slip-fit joint. Drill the required number of holes for the solid rod struts evenly down the length of the tube assembly. Drill all the way through one side. I will give you a trick for drilling into the side of round stock a little later. Insert strut rods into the holes just enough that the ends make complete contact with the walls of the hole (Figure 8 B & C). Carefully line up the struts square and solder them in. This is a good place to use wet paper towel strips to keep the previously soldered joints cool. Let this cool completely! Run a drill bit slowly down the inside of the tube to remove the protruding rod ends. Now cut to separate each piece and remove any burrs. Make the strut rods overly long and cut them off later. When you do cut them off be sure to leave a generous extra portion to fit into the rib (wood frame) or extend into the hull (fiberglass hull) for adding reinforcement. This is stronger than my previously mentioned butt solder joint, and looks more prototypical as real ships had bearing housings at the strut to shaft joint. Reinforce the shaft to hull joint with putty type epoxy on the inside for a fiberglass hull.

XIV.    DRILLING ACCURATE HOLES IN THE SIDE OF A ROD OR TUBE

    Now the trick to accurately drilling a hole in the side of a rod or tube. Use a bushing the same diameter as the rod with a hole the size of the drill accurately drilled lengthwise through the center (Figure 8D). Place the tube in a vise and set the bushing on top of the tube in the location of the hole. Tighten the vise and you can now drill the hole using the bushing as a guide (Figure 8E).

    Accurately drilling the hole in the bushing without the use of a lathe is difficult. For our jobs, as we are using standard sizes of brass pieces and drills, simply solder up a series of tubing sections from the next size larger than the drill to the size of the rod or tube. Instant (almost) bushing. Be careful not to tighten the vise so much you distort the tubing. If possible always clamp the vise down when drilling brass, as brass has a tendency to grab the bit and can then start flinging things around.

XV.    MOUNTING MOTORS

    The best way I have seen to mount motors is to use the mounting holes provided in the shaft end of the case. If there are no threads in these holes use SS sheetmetal screws. In all cases use a thread locking compound. The drive motors can be mounted by fabricating a mounting plate for fiberglass hulls or building the mount into a rib on a wood framed ship. If you are using a mounting plate reinforce the plate to hull joint with a putty type epoxy. A good idea is to provide a more durable surface on the screwhead side of the plate or rib. I use a washer the same diameter as the motor fabricated from thin fiberglass circuit board.

    I have made motor mounting templates for all my motors to ease construction of pumps and mounts. These are simple to make and save time if you ever build another ship or pump. Templates for several motors can be made on one template piece. Take a piece of clear Plexiglas or thick plastic and mark a location for the hole for the motor shaft, center it between two of the edges. Carefully measure the distance between the mounting holes and mark the these locations. Centerpunch the location for the motor shaft and drill a hole the same diameter as the motor shaft. If the motor shaft is not an exact drill size drill to the next larger size. Insert the motor and verify that the marked locations for the screws still line up. Center punch and drill these holes after making any corrections. Drill out the holes to one brass tubing size larger (1/32") than the desired clearance. Cut a short piece of tubing for both holes and press them in place. Carefully cut off and file smooth any excess. The purpose of the tubing is to protect the plastic from the drill bit when you use this template. Whenever you need to fabricate a mount locate the desired center for the motor and drill for the shaft at this point. Insert the butt end of the drill in the template and through the hole. Now use the proper size drill to make the screw holes. Pump cases crack and are chewed up as periodic maintenance is performed and these templates come in handy as new cases have to be made.  The template shown in Figure 9 has holes for both the 380 and 540 style cases.

Figure 9

    As a further note on motors, when mounting the drive motors try to end up with the motor in line with the propshaft. While the universals can allow fairly severe misalignments, this adds friction to the assembly and thereby increases current draw and reduces prop speed. Also at the more severe angles you run the risk of a bump or slight looseness pooping out the universal.

XVI.    MISCELLANEOUS NOTES

    Mount your stern guns in the lowest turret firing level with the water, or hitting a fixed distance behind your ship (4 to 6 feet is typical). This orientation does not provide as much opportunity to hit the waterline as a higher mount angled down, but you will have a much improved ability to hit the target. With the guns mounted to angle down you can get waterline or just below hits, but only over a narrow range. The rest of the time you hit superstructure or the BBs bounce up and out of play. The main purpose of a stern gun or guns is to score points and tear up the sides of a ship so if it starts to sink it will quickly run into trouble, not to inflict immediate killing shots. Captains dislike a walking series of double or triple holes down the sides of their ships as much as a few belows.

Lastly a few random notes:
    The plastic tube in the center of adding machine paper rolls makes an excellent raised catapult mount.
    Shaving cream and spray paint lids come in a variety of colors and will securely hold a marker float.
    Use the fishing floats made out of foam, they will not shatter if hit.
    Use the spiral cable wrap available at Radio Shack to protect your gun magazines and riser tubes from BB dents.

Return to Reliability Menu

Return to Construction Articles