Hi all I have located an 850 motor and mount at Howes Models in Kiddlington not too far from where I live in Malmesbury, for £22.50 however the prop shaft is 4BA, the coupling is not a problem as I can get the insert for the larger motor to fit the existing red coupling, but I can only seem to find 4mm 40 or 45mm propellers which are a fraction bigger than the 4BA which I know will screw on but they would have a bit of a wobble on the threads and could give me an out of balance vibration, apart from drilling out the old propshaft assy and fitting a new 4mm one what else can I do? or does anyone have a old 4BA prop they can let me have?
[Score: 8/10] 46" Aero kits Sea Queen Single Propellor (2 Blade X Type 45mm) Direct Drive to a 3650 watercooled (2 Blade X Type) Powered by Lead Acid (12v) 7Amp/h Batteries Controlled Through Hobby wing 100 amp w/c (100Amps) ESC - Comments: I felt the need to build something large from scratch having built Sea Nymph Sea Rover aero kits Swordsman kit. Many GRP based I/C powered before converting many of them to Brushless power. In Feb 2017 I bought plans from ebay in readiness for a family trip to Wales. My brother in law has a well kitted workshop in which he produced Sailing dingy kits before retiring. The aim was to produce this boat for the least possible cost. Thankfully there are lots of ply off cuts in Wales plus an 8x5 sheet of 1.5mm so I set about making my own kit during the time I was there. The motor was to be a Marx Decaperm selected from my bits box which I chose to set up using the geared drive. On the first launch performance was lacking to say the least so the motor mount was adjusted to direct drive but alas performance was not much better then everything stopped. The wires on the commutator had become unsolder end a common problem apparently I've now fitted a 3650 brushless stolen from an early attempt of a Huntsman 31 built for my Grand daughter which had replaced the Graupner 600, she is now 19 and interested in other things beginning with B. Having fitted the brushless a lot of vibration was experienced his was traced to a misaligned coupling,next outing will be with a huco type of fitting just to check it out roll on Thursday.
Just spent a few hours fitting brushless motor to seabreacher....and 150amp esc ...problem working at these high motor speeds is vibration and motor has actually bent the driveshaft which is brass 6 mm ...next step is new shaft of steel....
Paul - luckily I have a new shaft as purchased one the other as Dave said about about making sure it true before fitting due to vibration issues later on if it wasn't true. Doug - I'm going to go for your's and Dave suggestion of fitting a fillet as to be honest it sounds easier and like Paul says its underwater so wont be seen and if it ever gets in the water wouldn't want to lose it on first trip out😁😁😁
Neil, the suggestions about prop support are all valid, just different takes on things. I would (if you intend to repaint the hull) sand off to key, or prime the old paint prior to installing the shaft, as it will be easier to repaint and prep. Question, sorry if I missed this, is that a new shaft with new bearings? If not get new from shg marine (they are at the Blackpool, show, and the midlands engineering show if you can get to either, I'm not sure where you are?) they are dirt cheap, called aceteal or something similar, they water lubricate, and cost about £2 each. Roll the inner shaft on a piece of glass or a mirror, this will tell you if its bent, any sign of this, get a new one, or you might have alignment and vibration issues. (glass is totally flat! there's a free tip to test you prop shafts ha ha !!👍) same can be bought from shg, and get stainless. Back to the support, the thing Dave mentions is a piece of wood that fits between the hull, and the shaft. The shaft is then epoxied to this, giving support, but it wont be true to original. You have the original support, so remodel this to fit your new angle. If you use any bolts etc to secure, use stainless so they don't rust. Once painted, it will be hidden, and its underneath anyway so cant be seen. It will need to be tight to the outershaft, once positioned, you could solder, as they are both brass, and either feed into the hull bend over and epoxy, or screw as per original. Here is my big fireboat, its twin, but the concept is the same, the support came into the hull, and on this example, I put a brass pin through, and epoxied it all
Thanks both Doug and Dave I do have a couple of different mounts which were purchased to try and get round my sticky motor which initially proved to the glue holding the shaft had failed causing vibration and the old diesel mount causing misalignment. I have just recently even purchased a plastic type mount like the one you have Doug😉 Should have removed the mount when you suggested it a year ago Dave but a little scared now I can start a fresh. Now thats done and new lease of life should see me busy at the weekend. Little concerned on the hungry and smelly motor but like the idea of a Lipo with Tamiya connector will have a look for those later. Was a little worried about drilling through but like the idea of dowel and sand paper nice and easy I think until I get bored and then probably resort to the drill lol. Thanks for all the advice and the confidence you guys give. Ill update my year old blog with progress over the next couple of weeks.😁😁
Some info. on radar, armament and wartime mods! 'Ya pays ya money and yer takes yer choice'! 😎 "Armament, electronics and protection The main armament of the Illustrious class consisted of sixteen quick-firing (QF) 4.5-inch (110 mm) dual-purpose guns in eight twin-gun turrets, four in sponsons on each side of the hull. The roofs of the gun turrets protruded above the level of the flight deck to allow them to fire across the deck at high elevations. The gun had a maximum range of 20,760 yards (18,980 m). Her light anti-aircraft defences included six octuple mounts for QF 2-pounder ("pom-pom") anti-aircraft (AA) guns, two each fore and aft of the island and two in sponsons on the port side of the hull. The 2-pounder gun had a maximum range of 6,800 yards (6,200 m). The completion of Illustrious was delayed two months to fit her with a Type 79Z early-warning radar; she was the first aircraft carrier in the world to be fitted with radar before completion. This version of the radar had separate transmitting and receiving antennas which required a new mainmast to be added to the aft end of the island to mount the transmitter. The Illustrious-class ships had a flight deck protected by 3 inches (76 mm) of armour and the internal sides and ends of the hangars were 4.5 inches (114 mm) thick. The hangar deck itself was 2.5 inches (64 mm) thick and extended the full width of the ship to meet the top of the 4.5-inch waterline armour belt. The belt was closed by 2.5-inch transverse bulkheads fore and aft. The underwater defence system was a layered system of liquid- and air-filled compartments backed by a 1.5-inch (38 mm) splinter bulkhead. Wartime modifications While under repair in 1941, Illustrious's rear "round-down" was flattened to increase the usable length of the flight deck to 670 feet (204.2 m). This increased her aircraft complement to 41 aircraft by use of a permanent deck park. Her light AA armament was also augmented by the addition of 10 Oerlikon 20 mm autocannon in single mounts with a maximum range of 4,800 yards (4,400 m). In addition the two steel fire curtains in the hangar were replaced by asbestos ones. After her return to the UK later that year, her Type 79Z radar was replaced by a Type 281 system and a Type 285 gunnery radar was mounted on one of the main fire-control directors. The additional crewmen, maintenance personnel and facilities needed to support these aircraft, weapons and sensors increased her complement to 1,326. During her 1943 refits, the flight deck was modified to extend its usable length to 740 feet (225.6 m), and "outriggers" were probably added at this time. These were 'U'-shaped beams that extended from the side of the flight deck into which aircraft tailwheels were placed. The aircraft were pushed back until the main wheels were near the edge of the flight deck to allow more aircraft to be stored on the deck. Twin Oerlikon mounts replaced most of the single mounts. Other twin mounts were added so that by May she had a total of eighteen twin and two single mounts. The Type 281 radar was replaced by an upgraded Type 281M, and a single-antenna Type 79M was added. Type 282 gunnery radars were added for each of the "pom-pom" directors, and the rest of the main directors were fitted with Type 285 radars. A Type 272 target-indicator radar was mounted above her bridge. These changes increased her aircraft capacity to 57 and caused her crew to grow to 1,831. A year later, in preparation for her service against the Japanese in the Pacific, one starboard octuple "pom-pom" mount, directly abaft the island, was replaced by two 40 mm Bofors AA guns; which had a maximum range of 10,750 yards (9,830 m). Two more twin Oerlikon mounts were added, and her boilers were retubed. At this time her complement was 1,997 officers and enlisted men. By 1945, accumulated wear-and-tear as well as undiagnosed shock damage to Illustrious's machinery caused severe vibrations in her centre propeller shaft at high speeds. In an effort to cure the problem, the propeller was removed, and the shaft was locked in place in February; these radical measures succeeded in reducing, but not eliminating, the vibrations and reduced the ship's speed to about 24 knots (44 km/h; 28 mph).["
Trying to replace the motor mount in an existing model is difficult. Especially when there is structure above the motor. The former arrangement was geared and I am changing it to direct drive. Getting the alignment and motor vibration to allow for the smoothest operation is a lot of trial fits. This motor has lots of torque.
Hello folks. Brand new here, so go easy! I have searched but not quite found what I am after. Apologies if I've missed the obvious. Having just finished a 36" Fireboat with my son, I am now thinking about the larger 46" version. The little boat is running a Radient Reaktor motor / ESC combo which is 3000kV with a matched ESC and 2S1P LiPo battery. Performance is pretty good, although we're still ironing out some cooling issues and vibration (old model resurrected). I am going to do the big boat 'properly' so am looking for recommendations for power, ESC and batteries. I am looking for overscale performance and tend to run on choppy water with currents (i.e. rivers😁). Thanks in advance, everyone!
Hi Paul As I already have the Action sound unit (Whitby lifeboat engine sound, my model) and a 20w amp I sourced some resonators from Holland www.soundimports.eu/. They were out of stock for the initial order so I bought two lower power exciters to see what they were like. Attached to the back deck of my Trent and plenty of volume but the vibration was very visible. I have now received some 24Watt (Dayton Audio DAEX25FHE-4 Framed High Efficiency 25mm Exciter 24W 4 Ohm) similar to yours and they are attached to the hull sides above the waterline and sound great on the bench. Will be trying on our lake as soon as the weather improves but should be as good as the big 8" speaker I was using and several pounds lighter so the model will sit correctly on the waterline. Thanks for sharing this sound medium Mine are attached by 3M VHB (Very High Bond) adhesive so I am hoping if I need to move or replace I can buy some glue to re-attach Dave
Hi Doug, they are from mrrcsound, available on the website, they are called tt25 transducers. Having played with these at length with model planes, I now know the hull thickness isn't enough. The thicker the material, the deeper the sound, but you lose volume. Unfortunately once epoxied on, they don't come off, until the epoxy goes brittle, which does happen as the vibrations cause this. If I try to pull them off now, they will break. I have too much volume, and not enough depth. With a plane, due to distance away from operator, you need the volume, with the boat, they don't go anywhere near as far away from the operator, so I messed up here😭 Ill turn it down a lot, see how that works out
Hi Rolfman, I don't have a link, never looked for one!, but the the following observations - 1) it helps enormously if you own a small lathe, which I admit I do, and also admit not everyone does. 😉 Dremeling is OK - as far as it goes! BUT - a little offline (in the original mechanical engineering sense!😉) creates friction and vibration which negates the expense and effort to fit ball races in the first place 🤔 A lathe with a dead centre eliminates this source of error. 2) The ball race should NEVER be soldered or brazed. (When did you last see a car wheel bearing soldered or welded in?) Any process which includes applying heat to both tube and ball race can, and most probably will, damage the ball race, especially if it is one of the 'packed for life' types. You will boil the grease packing out of the race and possibly distort the rings. Correct technique would be to machine the tube (on a lathe for accuracy) to a few thou less than the OD of the ball race. The machining creates a step inside the tube, with depth to accommodate the thickness of the ball race. The end of the tube is then GENTLY heated and the ball race pressed in. This should preferably be done on the lathe using the dead centre to ensure concentricity. When everything cools down you have a tight 'shrink fit'. No other 'glue' needed😉 BTW: I have been pedantic using the term 'ball race' because that is what Allen has bought and shown in his pic. A 'bearing' can also be a simple bush, which can be soldered or brazed with less problem than ball races BUT - needs even more care with alignment as it has no 'give' like a ball race! I am faced with exactly this problem with corrections to my Graupner Graf Spee where one shaft and it's bushes are out of alignment 🤔 I will most likely replace the bushes with ball races. Hope I haven't discouraged you but I wondered why you went this way! Good luck, Doug 😎
its early on with this project, I was going to wait until its completed, but not sure when that will be, so Ill give you a sneak peak. I've been using a sound system in one of my model planes, and over time have become friendly with the guy who makes them, helping him with various things. I got thinking about the 4 foot fireboat I have, and how cool it would be to have a sound unit. So, to cut a long story short, I knew he had a plane sound with twin Merlin's for a bomber, and I use a merlin for my P51 Mustang model. After a serious amount of pestering, I got him to modify one of the 5 stock sounds on his Boat sound unit, using the twin Merlin sound from the planes. It took some work, getting rid of the propeller sound on the start up and shut down sequence. I ran it for the first time last night, but forgot to take spare batteries, and a small screwdriver to adjust the settings, so couldnt change the settings, in particular, the volume was set way too loud, losing some of the clarity of sound. This is pretty close to the real engines, which where v8 meteor, this sound is an actual recording of the v12 Merlin, its doubled up, and staggered, so you can hear the two engines running. It has start up and shut down sequence, it isn't clever enough to read reverse unfortunately. Its a speakerless system, using transducers instead of speakers, which are much louder, smaller and lighter. They rely on vibrations, they are epoxied to the hull, and the whole boat becomes the speaker! Its the first time I've done this, and its pretty new on the market for boats, planes have been going for a few years. I've realised that whilst I put them above the waterline, I didn't account for the roll of the hull, when one (there is one on either side) goes below the waterline it muffles the vibrations, and causes a funny sort of gurgling noise, ah well, like I say, its early days! Still a bit of tweaking to do, but you get the idea. Stock sounds are Turbo cat diesel, Johnson outboard, evenrude outboard, mercule v8, steam. They also have aux sounds, such as ships bell, steam whistle, horn, seagulls etc. I think on my system the Johnson is dropped in lieu of the twin merlin sound. Have a look at www.mrrcsound.com https://www.youtube.com/watch?v=EkJUHe1tR_w
Exactly the ship's screw should be behind the rudder so that the ship responds well and if the shaft is below that angle, the boat will crawl in turns in the water. I would also avoid connecting the shaft with the kardan engine. Just a smaller branch in the water and the kardan bursts. I use the Compact shaft - the motor is screwed directly to the shaft and connected by an aluminum clutch and tightened by screws. Then less tilt of the shaft can be achieved. Or if the kardan engine on the bulkhead in the ship is bolted and does not get as great vibration as in your design.
Hi Doug It's a tinny type noise, no vibrations or anything I can see/feel.... I'm using the Tamco Tx and Rx along with an Mtroniks Viper 20 ESC....once it's all switched on the green rx light is on and the red/green light is on on the ESC....the Tx is also switched on and all is quiet...once the throttle moves the sound starts...possibly the motor, could be a normal sound one should expect....the coupling appears ok