Hi all for the second blog report on the schenllboot I am going to go over the rudder an propeller shaft assembly in more detail. The first stage was to make the rudders which were made of brass ,and having taken note of what has been said about the increase in size needed for the kit by other members I have increased the size of the rudders by 50% so that they have more effect and hopefully the boat will be more agile .I fitted 3mm treaded rod on to the rudder and in a 4mm flanged tube to reinforce the brass rod. The second stage was to make and fit 5mm flanged tube in the location for the rudders in the boat , these were made to be above the water line and will be sealed in place to reduce the possibility of leaks. These were fitted to a rudder platform inside the boat which was fitted to the kit moulding for the rubbing strip that runs the length on the boat and secured by making resin blocks which were fitted with computer extension nuts .which were then superglue in place to secure the rudder platform. The rudders were then fitted in place and held in position with the tiller collars which were made from 8mm rod and fitted the tiller arms and locked in place with 3mm computer screws and ni-lock nuts, a connecting plate was then fitted to connect the three tillers together, I also fitted rubberised washers to seal the rudder tubes. The third stage was to make the propeller supports. The centre support was a direct copy of the kit part made of brass and fitted to the kit with a plate and screws (this plate and the rudder plate were made from galvanised steel)and will sealed with resin after the I test the boat for leaks. The port and starboard supports were made by taking the kit parts and cutting them in have along the joint line or mould seam this gave me a template ,which I used to make cross-section segments but I did alter the template by increasing the boss diameter to 10mm and extending the support legs so that the finished support could be fitted through the hull (the picture of these show the mk1 version where I forgot to allow for the 4mm prop shaft which has a 6mm tube) any way the boss of these segments were drilled out with a 7mm drill and a length of 7mm brass tube fitted through the boss to assemble the segments, all of which were coated in soldering flux at this stage of the assembly which were riveted at both ends to hold it all together during soldering, after soldering the supports were then filed to the size and shape to resemble the kit parts as close as possible and fitted to the hull using a superglue and talcum power mix and then I cast resin around the extensions to secure the prop supports in place. The forth stage is the propeller shaft housing for the centre propeller housing I place a brass rod in a plastic straw and place in position in hull and using resin I sealed the hull with the rod in place this gave me a pilot hole for the centre prop shaft after I removed the brass rod. For the port and starboard shafts I used the kit parts which had hole place when assembled, this when I reinforced the housings ,the centre housing I glue 2mm of plasticard on each side and for the port and starboard I made a brass tube shroud which covered the housings which left gaps between the kit part and the brass which was filled by casting resin in the gap this increased the diameter to 10 mm so that there were little chance of breaking throw with the drill and finished these off by fill-in the outside with body filler and sanded to shape and finish . I then drilled through the pilot hole in the housings using very long extended drills and a wheel brace ( if I had use a power drill the heat would have melted the plastic of the kit and may have caused problems) I drill the shaft housings out 6mm them filed them out with 6mm file so that I could insert a length of 6mm brass tube. After all this was done I fitted a flanged bush made from 7mm tube and 2mm brass plate turned to 11mm to the ends or the propeller shaft housings. And now it is time I have to ask for some help could any one advise me on the length of propeller shafts , I know I can use a 300mm shaft for the centre shaft but port and starboard will have to be longer . and I also need advice on selecting the motors , I want to use 4mm prop shaft with 35mm propellers. Any opinions welcome.
Hi Shaun, This design of hull forces the craft higher and higher the faster it goes. When it is high on the plane and almost hanging on the last few inches of propshaft it can fall off the plane either way, usually to the right (Starboard) side because of engine torque. The full size boats were fitted with 2 or 3 engines to help counteract this. The British Powerboat Company, who originally designed the hull that Vospers copied back in the 1930s/40s also noticed this which led to double skinning the hull with 1 inch thick mahogany for extra strength against pounding and falling on the waves. Lowering the drive angle of the propellor shafts and adding more weight from the C of G back to near the stern. We build this 3 screwed designed hull with one mainshaft usually so do not have the benefit of shaft rotation to stabilise the boat at speed. It was in the 1960's that Fairey engineers had the same problems (Swordsman,Huntsman etc) They came up with large transom mounted powered Trim Tabs. Their boats had similar problems and only one shaft in the main. I suggest you try fitting 2 x 2 inch wide by 1 inch deep trim tabs at the very bottom of your transom midway between the keel and the chine as well as move your battery packs forward a bit initially. Try some fast tests with this, you only need 2 to 4 degrees of down on the tabs initially. Add removeable weights near the CG as needed, a bit at a time but don't stop the bow lifting up onto the plane. Have fun, best of luck. Ron Rees
Billing boats, which took me 3 years to build.Hull was planked and theh fibre glass. Boat has full functional remote with seperate port starboard control,rudder and bow thruster. full inside and mast lighting.
I remember when I could do detailed work. Like that not any more! Eyes just don't do that any more!😡 Running light will be port starboard and one steaming ahead light top of main mast! for a total of three lights on that circuit! Deck lights will be 6 white lights going around the main cabin. I figure I'm going to use 3 Volts for each circuit! What do you recommend for the resister values? Since they are LED's I figured 3 volts should be OK right! The LED's are the 3mm clear type! Thanks!
Not me, never heard of 'em til now, but here are the specs and a pic😉 https://en.wikipedia.org/wiki/Huckins_Yacht_Corporation Happy Huckin', Doug 😎 Technical Specifications Lindsay Lord, a commander in the United States Navy who was stationed in Hawaii during the war, examines wartime PT boat design in his "Naval Architecture of Planing Hulls" and records the Navy's planing hull research and findings. This is the most complete source of information on PT boat hull design and construction, and provides hull test data as well as detailed analysis and comparisons of the various PT boat designs. U.S. Navy Technical Specifications of the Huckins PT Boat (Patrol Torpedo) Motorized Torpedo Fast Boat: Crew: 11 Length: 78 ft (23.77 m) Beam: 19.6 ft (5.97 m) Draught: 5 ft (1.52 m) Displacement: 42 tons Machinery: 3 x Packard 12-cylinder gasoline engines delivering 1,350 horsepower each to 3 x shafts. Surface Speed: 40 kts (46 mph) Range: 0 miles (0 km) Armament: 4 x 21-inch (533mm) torpedo tubes for 4 x Mark 8/13 torpedoes, launchers arranged as inline pairs along port and starboard sides. 1 x 37mm OR BOFORS 40mm Dual-Purpose cannon fitted on forecastle. 1 x 20mm Oerlikon anti-aircraft cannon at stern 4 x 0.50 caliber (12.7mm) anti-aircraft, air-cooled heavy machine guns in dual mounts (2x2), one emplacement amidships and one forward, offset to starboard. Optional 0.30 caliber machine guns, mortar launchers, rocket projectors and additional 20mm cannons (and captured 23mm anti-tank guns) as required/available. Ship Class: PT 95 Number-in-Class: 18 Ships-in-Class: PT 95-102; PT 255-264 Initial Year of Service: 1942
Hi Peter, you're right about the sanding down. Take your time and apply a generous Dollop of Patience 😉 Any short cuts here will show up all through the painting process 🤔 See my Sea Scout 'Jessica' renovation blog re hull restoration!! My motto for painting is 'Brush for little fiddly bits, spray for big bits' e.g. hulls. I agree model shop spray cans are usually small and relatively expensive for big hull. I use giant cans from the professional suppliers, again see my Sea Scout blog for descriptions and suppliers. Also agree about care with the thin skins. After sanding and sealing, with Lord Nelson pore sealer, I reinforced my Sea Scout inside (where I could get to!) and out with DeluxeMaterials EzeKote resin. It's not the cheapest but it's water based, doesn't pong and doesn't need mixing with hardener Brushes just wash out in warm water. Couldn't be easier 😊 Flat off starting with about 600 or 1000 grit annd work up to 3000 grit and you should end up with a finish like glass - see decks of my Sea Scout😊 For my ELCO PTB I bought Colour Coats MTB Green (from Sovereign Hobbies in UK) for the darker camo patches and Italeri Flat Sky, # 4856, which is almost identical to the lighter Pacific Green for the base coat. After painting and detailing, pennant number and decals and such, I shall seal it all with a matt spray varnish. i use the big Lord Nelson spray cans for that. Re Gun Tubs: love the gun carriages but I guess they're much too big for my 28" boat. 😭 BTW: forward gun tub is too far forward. It should be further aft just in front of the screen round the bridge entrance starboard side and should be set half into the forward cabin. Just cut half of the lower section of the tub away on the inboard side to match the cabin height. See pics. You might find this Pinterest site useful for more detail👍 https://www.pinterest.de/pin/557039047643301834/ Register to get full access, it's free and you can get updates for the things that interest you. Hi Ray, attached are pdf files of the Aerokits plan. Just scale up to what you need and awaaay you go 😉 Look forward to the Blog👍 Cheers Doug 😎
Main mast in place. Dumas has the mast being held by small staple you have to make! I guess if your going to make the mast removable ok! But I'm going to put wires on my mast! So the mast has to be a bit more stable and more secure in it's place. So, I made a support base using 1/8" ABS. Which I laminated to give it more gluing surface. This I then glued to the cabin! I put angles to keep the piece from moving port or starboard. This made the mast feel solid! Eventually I'll start painting her! But for now I'll keep working on her! The mast is suppose to have one light suspended above the deck. But I’m going to run wires to power one light aloft. I believe it’s the steaming ahead light….
Hi Steve, Many thanks for those very informative tips. I mention the sticky problem, only that I have a trumpeter Bismarck, and I attempted to put on the forward deck, I tried to line it up with the first barbette ( I think that's the correct title, maybe wrong spelling), only to find I was off 1mm on the starboard side, tried to lift it, and #=*# it snapped,very fragile. Just noticed the time, talking boats at nearly midnight Wierd..... Peter
Yes, the Jersey City is a smooth sailing tug! I have mine low in the water. She grabs the water and doesn't lean as much! If she was at the water line dumas recommends she'll lean port or Starboard! Do you have the Brooklyn?
Aha! A forum in my neck of the woods, thanks for the tip.👍 Seems the owner of the speedboat was praising the strength of his boat's hull, from the manufacturer MHZ. "Der oben genannte MHZ (Modellbau Hobby Zavarsky) hat wirklich gute Rümpfe! Mein rotes Schiff hat ein wenig graue Farbe abbekommen, sonst nix... " 'The above mentioned MHZ has really good hulls! My red boat only got a little grey paint, other than that, nowt ...' Following comment was- Ships coming from starboard have right of way, doesn't look good for you!' 😎
Hi Jugge, love the lighting👍 Small tip😉 the red & green Port / Starboard lights should only be visible from ahead and up to maximum 90° to either side. This is so that others can see if the ship is coming towards them or going away. Happy sailing, all the best Doug 😎