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    Forum
    New Smoke Generators
    HI to all, I hope everyone had a good Christmas... I have started a new line of smoke generators here In Australia, At the moment I have 2 sizes available and more on the drawing board. These new units will run on 12 volts and draw about 1 amp using oil based fluid. Two Sizes SG-1 80 x 45 x 50mm outlet 1/2" This unit Is design for the smaller craft or small spaces a neat little unit that performs great runs for 25mins on 1 fill of the tank (25mls) $65.00 SG-2 100 x 65 x 60mm outlet 1/2" Designed for the larger boats with a bigger tank and more powerful fan unit runs for 40min on 1 fill of the tank (35mls) $75.00 Both smoke generators can be connected directly to your
    power supply
    or to your motor for control of the fan speed ( Just need to make sure your speed controller can handle the extra power) you can set It up for 1 stack or 2 with 1/2" copper pipe fittings from your local Hardware shop.. Kit Includes : 1 x Smoke generator 1 x Smoke fluid (100mls) 1 x wire (300mm) 1 x nuts & washers Check out the short clip of the smoke generator SG-1 at youtube http://www.youtube.com/watch?v=g3vpE0-ovlA or on my website www.modelboatsandfittings.com email: *Removed, PM Only - Admin*
    14 years ago by shane
    Forum
    Slightly confused newbie
    Hi just a thought the VIPER 25 AMP has a BEC (Battery Elimination Circuit ) built into it and if you connect a
    power supply
    to your receiver as well to power from the motor battery all manner of thing can go wrong John
    5 years ago by JOHN
    Forum
    Smoke/steam output for models
    Well Doug I have got one of these vapour cigarettes, free of charge, but need to get a
    power supply
    for it, it runs on 6 volts, will add some pictures when it arrives tomorrow, apparently it has adjustable air flow and has a 25ml reservoir for the oil. Cheers Colin.
    5 years ago by Colin H
    Forum
    Proximity (Hall effect) sensor wiring
    Absolutely Steve ๐Ÿ‘ Alternative is to make a holder for the magnet to prevent it getting knocked off by weeds etc. Also agree that any Failsafe' circuits must have an independent
    power supply
    . Place to put the switch, or latching relay, is definitely in place of the little slide switch usually supplied on the ESC. Just checked on some of my ESCs, Graupner and mTroniks, the red lead to the switch is NOT connected to the red lead supplying the RX and servos via the built in BEC. Guess the switch just triggers an FET switch inside the ESC. So the normal 500mA limit of reed switches will be enough. if a latching relay is used make sure the pull-in current is less than 500mA. Have fun All, cheers, Doug ๐Ÿ˜Ž Eric; which sub is your mate building? I have a Type 1A U-Boat dynamic diver, speed and planes only, and a kit for an Akula 2 which will be a static diver, with tank etc.
    6 years ago by RNinMunich
    Forum
    Proximity (Hall effect) sensor wiring
    I do not know how much knowledge of electronics your friend has but I need to point out that a hall effect sensor is not like a relay. While they do act like a switch ( sort of) they need to be powered and have a hall effect voltage to switch. This would mean in the use intended there would be a current drain on the sensor and if the
    power supply
    ( battery?) voltage fell to far it would not function. The effect you want could be replaced by a reed relay cheap and simple to use. However reed relays can only pass low currents so would need to be cascaded with a higher rated relay before switching the main battery supply on and off. https://www.ebay.co.uk/itm/10-Pcs-2-5X14mm-3-Pin-4W-Glass-Reed-Relay-Magnetic-Switches-N-O-N-C-SPDT/372165424048?hash=item56a6c9b3b0:g:vgAAAOSwJtdaL2~p:rk:53:pf:0 these reed relays have both normally open and normally closed contacts and at a couple of quid for 10 worth buying so he can experiment.
    6 years ago by Haverlock
    Blog
    The wheelhouse navigation light.
    This is a small item but very visible on the wheelhouse and since the standard for this item has been set I have to follow suit. So first of all get some 3mm blue LEDs ordered and then itโ€™s on with preparing the white metal body. I used by hand as suggested a series of drills increasing in diameter until 3.1 dia was reached but only 2/3 down the length from the front the smaller hole (1.5mm) was bored right through for the wires to exit. Arrival of the LEDs, first check the LED using my
    power supply
    , just over 3 volts seems to illuminate to the correct level. Next was to remove the shoulder on its plastic casing so the whole body does not exceed 3mm over its length and lightly abrade the outside to give a diffused light. Next cut the LED legs to 2mm from the plastic casing noting which is positive, next prepare the wires. I used Futaba servo wire cable 22awg which is very flexible and with the white signal wire stripped off leaving a red and black wire. These were tinned and cropped to 2mm and then quickly soldered to the appropriate terminal. Next check the LED still works! first hurdle over, I now needed to check the that when the LED goes into the body it doesnโ€™t short out so checking the diameter over the widest part which is over the soldered terminals this was 0.1 below 3mm. I decided that shrink sleeve was too thick so I mixed some epoxy resin and coated all around the terminals, this proved to be satisfactory in both non-conductivity and dimensionally. Now the final test, using some aliphatic wood glue I slid the LED into the body whilst it was illuminated as it was a tight push fit, bingo itโ€™s still lit โ€“ leave to set. I used aliphatic glue, as it would be easier to remove should I ever have to change the LED. The body still needs painting white but this will be done with all the other fittings at a later stage.
    6 years ago by mturpin013
    Forum
    Equipment wire
    Hello, try looking for old 25way data cables at your local car boot sale. The cores are multi-coloured and very thin. Most LEDs only use a breath of current to drive them so you won't start a fire! Here's a tip about dropper resistors for LEDs: put them at the
    power supply
    end where you can tie them down securely. Also, the formula for finding the resistance you need is: R equals Volts(supply) minus Volts needed by LED (Vf) divided by the required LED current (If). So, say 12V supply, 2V LED wanting 15mA = 12-2=10/.015 = 666.667, so you'd use the nearest value above, which would be 680ohms. Easy! The size of the resistor in watts/milliwatts is found by I(current) times E(volts), so 10X.015=.15W, or 150mW. Hope I'm not teaching an old sea dog new tricks! Starting a new Firefloat - oh boy.๐Ÿ˜ฒ
    6 years ago by b111yboy71
    Forum
    Voltage increasing via regulator
    A somewhat confused question if I may say so Eric!๐Ÿ˜ฒ You can't 'regulate up' only down. The regulator's job is to produce a constant lower voltage from a range of higher voltages. I often use one to produce 5V for the RX and servos from a 12V SLA drive battery. A little 3 legged device (type LM7805) which looks just like the power FETs in a high current ESC. My version of a UBEC! ๐Ÿ˜‰ What is this 'regulator' you have? Type number? Manufacturer? Photo? To get 12V from 7.2V you would need to use a Voltage converter (also known as an inverter). This works by converting the DC input from the battery to an AC voltage which can then be increased using a transformer. More elegant (and expensive!) versions use a transistor oscillator and amplifier. This uses hi-power transistors instead of the transformer. The AC output of the transformer (or amplifier) is then rectified back to DC. All this is very inefficient which is why it is normally only used for very light currents, where the losses are not so significant, and when there is no other alternative, not often the case! You can't beat the physics and you will never get the same power out that you put in. This leads to a basic design question:- What is the total current consumption of the load? I.e. the motors. A simple example:- Let's say that at 7.2V the motors draw 10Amps total, i.e. 72W (or VAmps). Assuming a utopian 100% efficiency at 12V this would equate to 6A. Due to the three stages of conversion; DC to AC, transformation / amplification of AC to 12V, AC back to DC, you'll probably be lucky to get an efficiency of around 60% to 70%. Thus if you stick 720W in you'll get around 430 to 504W out. Not much of a gain is it!๐Ÿค” Your battery would be exhausted in about 2/3 the time it is now ๐Ÿ˜ก If your motors draw more than 10A the problem just gets worse. So what is it you really want to do? If you just want to up the volts to your motors stick a 12V SLA or an 11.1V LiPo (3S) in and hope that you don't cook your motors! Frankly I don't really know why you're bothering, tugs aren't sprinters! If you want more pulling power with the existing setup try experimenting with prop sizes and pitch. Will probably achieve much more than fiddlin' about with voltage converters. BTW: All this assumes that the RX has it's own separate 5V battery supply or from a BEC in the ESC. Some clarification needed from your side. Cheers, Doug ๐Ÿ˜Ž
    6 years ago by RNinMunich
    Forum
    Taycol Supemarine Resurrection
    Well Doug, have been to Ludlow today and saw a Sea Queen on the River, it was powered by a Supermarine, driving a 50mm x 50mm brass prop.
    power supply
    was 12v 7ah sla using a 30 amp. esc. it looked fantastic on the water, even against the current it was moving ahead with full power. if my sea commander goes that well I'll be as happy as a dog with 2 tails. Cheers Colin.
    6 years ago by Colin H
    Forum
    Nomenclature...
    Hi John, think somehow you've got the wrong end of the stick!๐Ÿค” All BECs are Battery Eliminator Circuits of one sort or another. The objective is to eliminate the separate receiver battery, sometimes necessary purely to save weight and/or space in small models. If you do that then the RX power must come from the main drive battery, which then has to supply all RX functions; servos, switched lights etc etc. Personally, if the boat / ship can carry it, I prefer to use drive batteries for just that and use separate battery for the RX and special functions. Some of which, like smokers for instance can be current gobblers. Cheers, Doug ๐Ÿ˜Ž PS if you ever find a way of eliminating all batteries and still get the RX to work and the boat to move PATENT IT QUICK!! ๐Ÿ˜ Cheers, Doug ๐Ÿ˜Ž Hmmm! Maybe a raft towed behind with an array of hi-current solar panels!? ๐Ÿ˜๐Ÿ˜ Years ago in my work in NAVAL COMMS systems I once suggested to a shipbuilder, who was complaining about the number of antennas needed, to put some of them on a raft behind the ship ๐Ÿ˜‰ Now they are doing just that with antenna buoys from submerged submarines! No credits ๐Ÿค” ... SIGH ๐Ÿ˜‰
    6 years ago by RNinMunich
    Response
    lastest progress
    Hi TJ, that instruction is quite correct๐Ÿ‘ It indicates that the ESCs have Battery eliminator Circuits (BEC) which means that there is an internal circuit which 'syphons' off 5V from the main drive battery to supply the receiver via the red wire in the ESC to RX cable. The ESC itself takes it's power from the drive battery. If all three red wires are left connected this will cross couple all three BEC circuits and may well damage the ESCs. The RX only needs one
    power supply
    ! ๐Ÿ˜‰ In my multiple shaft boats I usually disconnect all the red leads from ESC to RX and fit a separate RX battery. Cheers, Doug ๐Ÿ˜Ž
    6 years ago by RNinMunich
    Forum
    Martin's Taycol Conversion Boards
    Hi Martin, No! That was just the standing current of the bridge rectifier with the 'throttle at neutral. Off load max current flat out was 2.5A. So about 15W, should be enough for 'plodding' fish cutter. The 'gizmo' is a 30V 5A regulated
    power supply
    with adjustable current limit. Very useful for such experiments. if I 'b****r up the wiring with a battery connected .... ๐Ÿ˜ก I expect for your Supermarine and Special that will be more like 7 to 10A. At the moment the boards are fitted with 10A fuses, I'm wondering if I should put in 15A. What do you think? You know the bigger motors, I don't, only have the little Target. it also growls when flat out ๐Ÿ˜‰ The fish cutter has a 35mm 3 blader so hope to be able to able to answer your question re loaded current shortly. Re brass bashing; FUNNY you should mention that ๐Ÿ˜๐Ÿ˜‰ Details later per email. Cheers, Doug ๐Ÿ˜Ž
    6 years ago by RNinMunich
    Forum
    LED Tug Mast Navigation Lights
    Doug: Youโ€™re right about halogen lights. Theyโ€™re mentioned as halogen in one article but as mercury vapor in a few others. Over here mercury vapor lamps are used for highway & parking lot lights & they do have a soft, yellowish glow. Halogen would be quite harsh & hard on driversโ€™ eyes. Maybe a tug or similar boats would prefer mercury vapor lighting in deck areas because theyโ€™re quite effective at cutting through fog? MVs are a good choice for highways & parking areas for the same reasons, I guess. By the way, in your spreadsheetโ€™s Notes column I noticed that you wrote โ€œClearโ€ for the two deck light LEDs when in fact theyโ€™re yellow when operating. it shouldnโ€™t make any difference to your calculations because you used the actual measured voltage in your calculations. Hereโ€™s a question. Suppose you were given a box containing dozens of clear & different colored LEDs, both the cheap tinted epoxy kind & the ones that have clear domes with different innards to give various colors. How do you tell what voltage they require? From what Iโ€™ve seen LEDs arenโ€™t marked in any way with a tiny numbers or letters so how do you know their power requirements if theyโ€™re not in their original packaging? Are LED supply voltage requirements standardized? Thanks, The Eternal Questioner (AKA Pete)
    6 years ago by PittsfieldPete
    Forum
    Windows, stoopid question.
    Ahhh! MiniCraft, Good stuff. I have their 'Buffalo' drill (with chuck), miniature jig saw, and table circular saw. All driven off the same variable
    power supply
    . Can't get spares for the saw blades any more ๐Ÿ˜ญ๐Ÿ˜ญ Bought the whole set about 40 years ago in a special offer from the AA (Automobile Association NOT what U lot are thinking!) . Drill been dismantled and cleaned / re-greased 4 or 5 times but still goin' strong ๐Ÿ‘ Proxxon not cheap, but good, well made. My lathes, milling machine and grinder are all Proxxon. They just go an' go an' go. Cheers, Doug ๐Ÿ˜Ž
    6 years ago by RNinMunich
    Forum
    LED Tug Mast Navigation Lights
    Hi Pete, Number 1, Get yourself some more batteries! You'll want a spare at the pond anyway ๐Ÿ˜‰ Better still, get a variable mains
    power supply
    for such bench tests so you don't have to mess with batteries until you're on the pond! Here in Munich I got a Basetech 30V 5A regulated PSU for less then the price of a decent boat kit. See 2nd pic, shows mine during my test of a converted field coil motor to make it run forwards and backwards. it saves a lot of faffing about with batteries for a quick test of a circuit๐Ÿ˜‰ Get one where you can set a current limit down to mAmps so you don't risk blowing components, e.g. LEDs! Re Connectors: if you are going to make a little distribution board for the lights then why not use this for all connections to the superstructure? I.e. first solder all the wires from the circuit board into the input end of your Veroboard. At the output end solder a strip of 1/10" pitch connector pins. Try Radio Shack! For each output to lamps, smoker etc you can then use the little 2 pin JST plugs. See pic. Type JST-RCY. Try Googling them. Sure you can get these from any half decent Online RC supplies shop over there. They are often used in Park Flyer planes etc. Doing it that way you only have half the wires to squash into the tiny plugs ๐Ÿ˜‰ As soon as we have the voltage readings we can work out the connections and resistors etc for your little board. Happy measuring๐Ÿ˜ Looking forward to your sketch. Cheers, Doug ๐Ÿ˜Ž
    6 years ago by RNinMunich
    Forum
    Warped wood
    My pleasure Martin, Thanks! Praise indeed from an 'old pro' ๐Ÿ˜Š๐Ÿ˜ I hope Dad wasn't to busy with the angels (or Vestal Virgins๐Ÿ˜ฒ) and had time to look down and check what his 'little boy' was up to ๐Ÿ˜ Yep the meter could help when checking the connections PRIOR to applying any power. More so if you use individual diodes. Easier is if you use a Bridge Rectifier (like I did๐Ÿ˜‰) which already has 4 diodes in one encapsulated block, clearly marked with the AC ~ inputs and the + and - outputs. That's the black block in the middle of my test board in attached pic. For your Taycols get one that is rated for 10 or 15 Amps. Use 10A fuses to protect the motor coils and a 15A fuse in the battery supply to protect the ESC and rectifier.๐Ÿ‘ I will probably put this board and the Taycol Target in the Danish Fish Cutter I am currently renovating - parallel to the PTB! Need to start two more Blogs! Glutton for punishment ๐Ÿ˜ Cheers, Doug ๐Ÿ˜Ž PS 2nd pic is the one I now use for my PC monitor background pic๐Ÿ˜Š
    6 years ago by RNinMunich
    Forum
    Charging NiMhs, one for Doug?...
    Evenin' Martin, Just back from 'nosh' with Gisela, my camera girl in the vid! She's mean like that too, keeps me hoppin' about like the proverbial cat on the proverbial hot stuff ๐Ÿ˜ก Can't wait to see the rotating teddy๐Ÿ‘ Put a couple of mini Cam lenses in his eyeballs and you'll get a terrific 360ยฐ First Person View from the driving seat๐Ÿ˜ Re Sea Scout, I took your advice and did the hull in Royal Blue (no navy knickers!๐Ÿ˜†) or what passes for that here. Anyway I'm pleased how she turned out. OK, I admit I accidentally turned her into a Sport Fishing Boat๐Ÿ˜ She's 24" what scale do you think that makes her? I'm looking for crew figures and stuff to fit out the cockpit but I'm not sure what size to look for. I thought maybe 1/20 i.e. a 40 footer? Waddya think? Re Kako; while recently trying (fruitlessly๐Ÿค”) to make space in the workshop (got two renovations on the go in parallel - saves getting the same tools, rattle cans an' stuff out twice!๐Ÿ˜) I ran across the original Kakos and Mabuchis I used in my scratch 53" H class destroyer Hotspur in 1966. She ran off a 4.5V EverReady flat (form not volts๐Ÿ˜) battery until Granny took pity and bought me some 6V Lantern batteries! I ran 'em up on a
    power supply
    and they turned but now sound like mini football rattles! Think they need new big end shells ๐Ÿ˜ Jeez, how many guys under pension age have ever been down to the bitza bazaar looking for 50 thou oversize bearing shells and compression and oil control rings?? Pics show her Sea trials in Radnor Park pond, Folkestone, Kent, summer 1966. Sorry about the quality, only had a Box Brownie 127 in those days and could only afford Gratispool free B/W films๐Ÿค” Pentax? Canon? Sony? Not to mention Digital? HD? Wassat? 50 years on I got all three๐Ÿ˜‰ I like Lupins too, preferably the blue and purple ones. BTW, for your steering guy's arms you don't need a separate RC function or channel! You just need a coupling from the rudder control to turn a pulley and cord which turns a suitably scaled pulley attached to the wheel axis. The arms are fixed to the wheel and go with it! Dead simple (to write anyway๐Ÿ˜) and no lecktrickery! ๐Ÿ˜Š OR you could just put one of his hands on the wheel and the other on the throttle. Then use a 'Y' cable to split the ESC cable into two. Connect the second output to a servo which moves the throttle lever via a push-me-pull-you-rod, pulleys and cord or gears or whatever. Sure you can figure out the mechanics better than I. Whatever, have fun and don't electrocute yourself, keep your socks dry๐Ÿ˜‰ Cheers, Doug ๐Ÿ˜Ž
    6 years ago by RNinMunich
    Response
    H.M.S BRAVE BORDERER
    Evenin' Rowen, So far so good, nice job๐Ÿ‘ Let me go through your comments one by one๐Ÿ˜‰ 1) "Moved the battery towards the stern and, at speed, the forefoot lifts slightly clear of the water. The plane is now almost flat. The battery is not well positioned when near the bow." Battery in the bow is almost always bad news๐Ÿค” too much weight forward of the CoG or natural balance point when planing. 2) "The 2S battery used was a 4000mAh 30C; suspect this battery does not have the capacity to operate the model. Every motor will run up smoothly until a second one is operated. The first motor then โ€œstuttersโ€ and a fuse might blow, this could be indicative of a power surge. Any comments from the electronic experts among the group would be appreciated." First the battery: you may be right. Especially with 3 x4500 kV motors Since you are using 3 ESCs how about feeding each one from a slightly smaller (lower weight) battery? Precondition of course is that all three are equally charged to the same voltage and capacity AND have the same (or very very similar) internal resistance! Complicates the issue of course and motors with a lower kV rating and one power source may well be the better solution๐Ÿ˜‰ Second the 'stutter': How and when did you switch in the second motor? If the first was still at 'Full Ahead', i.e. 'Pedal to the metal!, I might expect the battery voltage to dip and then recover with the sudden additional load and a sharp rise in total current drawn. But no particular excuse for a sudden current rise in the first motor ! Where was the fuse that blew? I suspect in the primary supply lead from the single battery๐Ÿค“ since with brushless motors you can't fit individual fuse in their supply leads like you can with a brushed motor. BUT you can to the ESCs feeding them!!! You can't get a power surge from a battery, not like a surge on the mains network due to lightning etc! But you can get a voltage dip and recovery if you suddenly present it with an additional load๐Ÿ˜ฒ 3) "The 3S battery was 10,500mAh and 40C; with this battery all three motors can be run at full speed together and fuses do not blow. it was also very heavy at 1700g, holding the model down." All run up together to full speed or 'switched in' as described above? There's a big difference between a gradual increasing of load on a power source and a sudden step increase! 4) "The motors are 4500 kV. On refection, think a slower motor around, perhaps 2000 kV would have been a better choice." I did think at the outset that 3 x 4500kV was perhaps a little ambitious๐Ÿ˜ฒ 2000 - 2500 sounds much better, and more controllable๐Ÿ‘ Then you could also get good performance results with a single battery of capacity lower and weight ๐Ÿ‘ The function of the third (centre) motor for 'action speed' would also be more pronounced๐Ÿ‘ 5) "Would concur with comments by others that a simple single or two bladed propeller layout for this model is probably best - that is unless you want to capture the true scale layout. The centre propeller seems to have little effect on overall performance, (see above re 4500kV motors- Doug๐Ÿ˜‰) although it will power the model quite nicely when operating by itself. Have had several suggestions about how best to use the centre propeller. Will think about them and decide later how to do this when I start to finish the model." As a 'Scale Purist' (as far as my skills and tools allow!) personally I would frown on the use of 2 blade props, much less only a single prop. Do that in a fictitious power boat if you will, but for 'Brave Borderer' ? ๐Ÿ˜ก Do her justice please๐Ÿ˜‰ Many three screw (๐Ÿ˜ฒ) boats (including the full size originals of this era) only used the third motor for additional manoeuvring speed in action situations. My personal experience of FACs (Fast Attack Craft) and FPBs (Fast Patrol Boats) over the last three decades shows me that the three screw configuration has been largely dropped, especially since the introduction of much more powerful engines such as improved diesels and gas turbines. Many use a combination of diesel, for cruising, and gas turbine for 'action speed', so called CODAG, COmbined Diesel And Gas turbine. 6) "The 2 blade Hi โ€“ speed propellers both increased performance and current draw. The model is more than fast enough with the original scale layout." As I believe the 2 blade props were of larger diameter (and perhaps also of larger pitch) than the 3 bladers the higher current draw is a logical conclusion! Stick with the scale config! ๐Ÿ‘๐Ÿ‘๐Ÿ‘ 7) "Will purchase a lighter, 3 S battery as that seems the best choice for performance and weight." ๐Ÿ‘ but don't overdo it to the other extreme by reducing weight and therefore capacity too much๐Ÿ˜ฒ You want a decent sailing time don't you? 8) "Testing using the bare hull with a minimum of detail worked well. For a models with a complex power train, this is a good approach as access to the internals can be gained easily. Nothing worse that finishing a boat carefully just to find the performance disappointing. Then having to to rip it apart to make major modifications or adjustments!" Heartily agree ๐Ÿ‘๐Ÿ‘๐Ÿ‘ Bon chance mon ami๐Ÿ˜Š
    6 years ago by RNinMunich
    Forum
    Radio in a yacht
    well you could use a LIPO battery and an independent BEC that way you have a way better
    power supply
    than pen cells in clips ( potential resistances on clips)
    6 years ago by Haverlock
    Forum
    Radio in a yacht
    most 6V sail winches will work fine on 4.8 volts. if you NEED 6V then things get way more interesting. Check to see what voltage your receiver can handle ( some have built in BECs some not). in the event your radio needs nominal 5V ( 4.8) and sail winch 6V then you need a 6V
    power supply
    and a BEC to power the receiver. However some sail winches have a built in BEC so you can power your radio via the winch. ( BEC= battery eliminator circuit in effect a voltage regulator )
    6 years ago by Haverlock
    Forum
    LiPo batteries
    Hi all, Lithium-Ion and Li-Po batteries do not take kindly to being stored long term fully charged. When they are new they will do it but after 2 to 3 years of intermittant use, can start to swell a bit and that is where the dangers start. When you give these cells the final run of the season and they show a charge in the the 3.3 to 3.5 (or so) volts per cell then they can be stored relatively safely. (This is called a holding or factory charge) Re start them with a balanced charge before you next use them. Do not constantly fast charge them as thi could induce swelling of the pack earlier. The old Ammo box is a good idea, any strong metal box will do but store them where it does not get very hot or very cold and ideally not in the house. Lipo cells are accepted as hand luggage by most airlines and a holding charge is recommended when flying, so remember to take a small 12v DC balance charger or 'Intelligent' charger with you to other countries, you will always be sure of a
    power supply
    , like a car battery even where the mains voltage is different. Small black plug-in cell monitors are readily available from places like Component shop and are a good guide to cell condition. One is these is quite essential as we use these cells more and more. Cheers, hope this helps. Ron.
    6 years ago by ronrees
    Forum
    Graupner ranzow refitting
    here we have some pics of the electrics as requested the first pic is of the mtronic 650 motors for main drive. second pic is of the twin rudder control. the third pic is of the water proof voltage dropper and connections for 5v
    power supply
    to some of the aux, Ron
    6 years ago by kmbcsecretary
    Forum
    Rx POWER
    Traditionally, when powering a Rx from more than one source, such as using a BEC circuit and a separate Rx supply battery, the positive power feed from the ESC is disconnected. This avoids the double power feed. I am embarking on a triple hand screw model with 3 x ESCs so each screw can then be controlled individually from the Rx. In this situation, where all the Rx power will come from ESCs running off the same main battery (using the BECC), with no separate Rx battery supply, is it necessary to cut all the positive ESC supply leads except 1? Appreciate any advice. Thanks Rowen
    6 years ago by Rowen
    Forum
    Rx POWER
    Yes that is correct you only need
    power supply
    from one feed . But I would recommend just removing the + pin from the plugs and taping it up rather than cutting the wires as you never know that they could be used in the future
    6 years ago by kmbcsecretary
    Forum
    Brushed motors
    Hi mate yes i believe you need to remove one of the power leads to the receiver you only need one 5v
    power supply
    . check out youtube ive sean a video on subject
    6 years ago by BigAlio
    Forum
    Graupner Elke HF 408
    Veeery interestink!๐Ÿ˜‰ I always thought that a motor's power rating referred to it's useful power output, not what it scoffs when it is stalled ๐Ÿค” Sure 40 x 7.2 = 288W but your full ahead current and watts measurement says the supply voltage was approx 6V. Interestingly some history research tells me that the Elke was originally intended for and supplied with a direct drive 280 motor. Graupner still lists it as such, albeit as 'Sold out' ๐Ÿค” Several German build blogs on the net confirm this, although others have also tried different motors, including Decaperms. Kit reviews (mostly on German sites) also mention that she was 'pretty quick' with the 280 motor. Can well imagine, I have 2 x 285s in my 107cm U-25 and she goes like a bat out of hell. ๐Ÿ˜‰ Allen; your result of 40W + and 6.77Amps tells me the motor was running on roughly 6V. (40/6.77=5.91) if you really had a 7.2V pack connected it's got a duff cell (collapsing under load or short circuit) ๐Ÿ˜ฒ Carefully strip the pack, isolate the duff cell using a digital voltmeter, cut it out and send it to the great recycling nirvana! Then you have a powerful RX battery๐Ÿ˜‰ Glad to hear you fitted the fuse๐Ÿ‘ Leave the rest alone for now and sail her and see. I believe you will be more than happy with the performance and since the ESC is over dimensioned it should have no problems. Happy sailing, Doug ๐Ÿ˜Ž
    6 years ago by RNinMunich
    Blog
    Sound System Try Out
    Well, back now from a wet Scottish break and with lots of little parcels to open..... Just before I left I tried to load a video and failed. My 'tutors' are going to help me with that but for now, the photos will do the job. The first image shows my temporary power setup and the layout of the components (1). Exciters sourced from ............. and the sound unit is a ............. Note the way they are wired up. I hope, when fitted properly, the cabling will run across the bottom of the Hull. The positioning was very much dictated by the space available between one set of 'ribs' (2). This seems to be just perfect. Note the position of the solder tags(3). There is little space left at the top when fitting the Deck, so keep as high as possible bearing that in mind. So I put the exciters in place, and attached my
    power supply
    (4). I could not wait to put the Deck back on before I tried, but at least I had sound of Motors and Horn and adjusted the volume control to 75% (5) Volume control being the white block with the cross head. So after I had my fun, I tidied it all up and put the deck on. Not screwed down but just to check sound levels. Did not work first time because of the lose wires, but second time was good and a great depth of sound. So that has confirmed the sound system fits and can work in that position. However, that is without motors running and that may make a difference. Next time I hope to be doing the trials of the mixer/escapes and motors, then I will see how the sound presents with motors running. All the best. NPJ
    7 years ago by NPJ
    Forum
    Twin motor control problem
    Hi John, Have you contacted Mtroniks about this at all. I have never received any answers to my email queries, but a friend of mine telephoned them with a query and they helped him. I agree with Dave and Doug too, but you have not yet told us if you have tried with a separate
    power supply
    to the Rx instead of the BEC.
    7 years ago by reilly4
    Forum
    lipo storage charge
    Thanks for the input. Sorry to have started a bit off a heated discussion. My charger was behaving somewhat differently to what I expected, having already watched many You Tube videos, But at the end of the day all is well now, mainly due the fact that my original
    power supply
    was a bit too wimpy and has been replaced by one with the required output. My batteries have now been storage charged and ready for action and a full charge at a future date. All I need now is a boat to put them in. Chris
    7 years ago by octman
    Forum
    Twin motor control problem
    I wanted total motor control on my large, heavy twin screw harbour tug. The rudder is pretty useless serving only as a sort of trim tab so I went the simple route: Each (brushed) motor has its own ESC and independent
    power supply
    so left and right Tx sticks control their appropriate motor. By doing this I am able to have one full ahead, the other full astern, to turn on the proverbial sixpence or for slick docking alongside
    7 years ago by Robin Stobbs
    Forum
    Twin motor control problem
    Hi, I have to say - I use a simple V-tail mixer only, and ESC at the basic setting, the transmitter => Throttle and Ail only(right stick). I tried to connect Rudder servo to this design, but I could not adjust it, the servo behaved "non-standardly". That's why I have it connected to the usual rudder channel nr 4 (left stick). One more important thing ... check the settings of the transmitter, especially the mixes that are sometimes pre-programmed from the factory. It is recommended to clear the transmitter memory first, and then set your own values. it usually helps ... I use the
    power supply
    of the receiver from a single source via an external BEC, powering motors using Y cables to ESC,from the same source as BEC ( gel Aku 12V).I had setup problems too - I finally found that one ESC was defective. after replacing both ESC no problems.
    7 years ago by tomarack
    Forum
    Tank Steering
    Hi Doug Twitchy servos suggest a bad connection, either bad crimp or dirty contacts. This can also apply to the small feedback servo wiper inside the case. Can be fiddlesome to clean but if you can't source a replacement you may have no option. if I have a duf servo I usually strip and keep all the bits for spares. Your non worker could be from one of the early offerings that required negative as against positive pulses. if its that old it is likely to be very slow. The motor and gears should be ideal for a radar scanner. Sounds like a Bonner offering, possibly used a split
    power supply
    . There is no mention of short range in the specs and as its possibly aimed at aero and drone markets I doubt if it has restricted range. Like you my scale boats are very precious and I like to keep them close to shore so range is never really a problem, just make sure the aerial(s) are above the waterline, especially if sailing a yacht!. Dave
    7 years ago by Dave M
    Forum
    ESC POWER
    Glad to hear you have solved your problem. Overrunning any system will result in some interesting issues and you are fortunate that yours shut down or failed open circuit otherwise all the electronics could have cooked. If you are getting a separate on-board power source the best option is to go for a switched mode supply, most will give you lots of amps without the heat problems of an ESC and are designed to work with higher battery voltages. You must disconnect any +ve power lead from any ESC to your rx. if your ESC has an on/off switch do make sure it is switched on, preferable before you power up the switched mode unit. Be good to see some pics or on water video Dave
    7 years ago by Dave M
    Forum
    ESC POWER
    Hi All, Diodes: - Trillium is correct of course, although some ESCs have a 6V BEC. Some RXs work off 3 - 3.7V for 1S LiPo operation in small boats. Not the case here. ๐Ÿ˜‰ As for stability I would guess that you get what you pay for! Cheap unstable, expensive stable!? Higher current versions with a switched supply? But the diodes are the only way to achieve the situation posed in the original question. Personally I wouldn't do it for all the reasons listed above. In RHs case seems to me the port ESC fault shot the BEC and robbed the RX of it's
    power supply
    resulting in total loss of control.๐Ÿ˜ก That's what shut down the stbd motor (ESC went Fail Safe) and why I asked if the rudder still responded; "No answer came the stern reply" ๐Ÿค” Why it may have failed Dave-M knows better than I, more practice! ๐Ÿ‘ Cheers Doug ๐Ÿ˜Ž
    7 years ago by RNinMunich
    Forum
    ESC POWER
    Hi rolfman Your quadcopters use forward only escs. I suspect the problem with model boat escs is the reverse. I don't have the circuit diagrams for ESCs so its difficult to be certain what causes the problem. I do know some escs with bec and switches work without being switched on if connected to a signal and
    power supply
    but subsequently fail usually with the full forward either on or off. Not all escs exhibit this which is why I asked what esc was being used. Trillium You are correct and is another reason I advised against this suggestion. dave
    7 years ago by Dave M
    Forum
    ESC POWER
    Hi Dave, I heartily agree. Why tempt fate? I have just bought a dual ESC form Hobby King to test with my destroyer. Otherwise the only advantage I can see in having 2 ESCs is if you want to use tank type control (2 sticks) to give power assisted steering! (Or mix with the rudder control?) If redundancy is the objective then a separate RX supply with NO BECs connected is the best bet. Happy sailing all, cheers Doug ๐Ÿ˜Ž
    7 years ago by RNinMunich
    Forum
    ESC POWER
    Hi RHBaker What kind of ESCs are you using? Doug I would not use both BEC units even with your diode in place. Most manufacturers advise disconnecting one positive lead completely. Also if the ESC has a switch both ESCs must be switched on as I have damaged one of mine because it was switched off but still appeared to work. Result was similar to RH Bakers problem. I suspect the Mosfet gate voltage was exceeded without the internal power to the ESC, causing it to go permanently on. I also believe this may have been developed over time as I am sure this instance was not the first. The ESC still worked OK in reverse but went full on as soon as the stick on the tx was put forward. Further checking also revealed the internal BEC was dead. Sealed unit so no chance to repair. Both As Doug says a separate
    power supply
    is a better option if you have room, and modern switched mode supplies are freely available and will deliver much greater power for all your servos, lights etc Dave
    7 years ago by Dave M
    Forum
    Smoke Generator (Water Vapour type)
    I recently required a smoke generator (ultrasonic Type) it is not in working order but I have rigged it up to test and bypassed the circuit board powered by 2 X 12 volt batteries and managed to get the vapourising unit to function, and the 12 volt fan motor with a separate supply to also work. With some work to replace the 12v to 24v converter CN6009 it should satisfactory. This unit appears to be a DIY job but very similar to MMB Foggy Smoke Generator which is available. Note the component required CN6009 I have sourced on ebay. Soon as it arrives I will set it up and test its suitability for a 1/24 scale TID tug boat model I am building. Problem might be size of smoke generator and other components required to fit in the hull in addition to a 12 volt 9ah battery scooter battery, there aint much space. There are smaller smoke generators available which burn oil (fan powered) which I have in one of my other models (Blazer Tug Boat) which is OK with no wind and close up but at any distance hard to detect if any smoke is being produced. The Oil recommend for this unit is Baby Oil which smells OK but I have wondered if I could use another oil based fluid which would produce more smoke (Any suggestions)?
    7 years ago by andyhynes
    Forum
    No power
    Hi Nick, we're working into this on a sort of Archimedian Spiral! But we'll get there ๐Ÿ˜‰ You forgot to mention if you had the rudder servo plugged in and if it responded! if it did I assume it responded to the left stick as your ESC responded to the right stick! in that case .. Switch off the RX (boat
    power supply
    /ESC), switch off the TX. Always use this sequence to prevent ESC / motors going wild! ๐Ÿ˜ก Then ... plug the rudder servo into the channel that responds to the right stick - I assume Channel 1? Plug the ESC into Channel 2. Switch on the TX, switch on the RX (boat supply / ESC-BEC). Again, always use this switch-on sequence to prevent uncontrolled servo / motor movement! All SHOULD now work as required ๐Ÿ˜‰๐Ÿ‘ Cheers Doug ๐Ÿ˜Ž @ Dave - Patience is a virtue ๐Ÿ˜‰
    7 years ago by RNinMunich
    Forum
    RAF rttl D2763
    A brief history After the second world war and as part of the occupational forces the Second tactical air force the RAF took over Sylt airport in 1945 and later in 1946 the RAF decided to use the airport and the airspace west of Sylt and Amrum as a firing range, and was known as RAF Sylt Armament Practice Station. From February 1948 to February 1949 the airfield was closed and prepared for the operation of jet aircraft. For target practice a target towing Squadron was stationed continuously on the station. The aircraft used were Miles M. 25 Martinet, hawker Tempest TT, DE Havilland mosquito TT. 35, Gloster Meteor F. 8, Meteor T 7. For instruction and training flights the flight also had some DE Havilland vampire T. 9s, hawker Hunter F. 4s, Hunter T. 7s. The aircraft of the target towing squadron were housed in the hangar of 402 near the South West of the Station. Therefore, the unofficial designation of weapon training squadron 402 was used at the time. For patrolling and securing the range area, as well as for rescue and training operations Marine Craft Section boats were stationed at List and Hรถrnum, Bristol Sycamore HR 14 rescue helicopters were Also station at RAF Sylt. Air traffic control boats and HSLs were stationed in the port of List at the beginning of the fifties (see pictures) D Boats In 1954, the decision was taken to replace the air traffic control boats and the HSLs with RttLs mk2s Rescue Target Towing Launch. As part of the rebuilding program to help the German economy the boats were designed and built by Krogerwerft Yard at Rendsburg. (Later taken over by Lursson ship builders) and were numbered D2762- D2766 these boats came in service mid 1955 which explains why my Father severed on both HSL and D-boats (preferring the D-boat) D2762 and D2765 Based Hรถrnum, D2763 and D2764 from List, with D2766 as a reserve boat in the event of maintenance or breakdown, Their design was very different to any other boats in the Marine Craft Section/unit more like the German Schenllboot or S Boot (allied code name 'E' Boat which my father always used), with flared bows and rounded bilges and powered by high speed diesels. The D boats were fitted with winches for Target Towing, these were removed as the boats duties were change to Range Safety and ASR These boats only served with the RAF, until 1961. Two were sold to the south African Air force D2762 and D2764 in1961, and the other three handed over to the Federal German Navy in 1961. All were subsequently used as ASR craft. D- Boats in German service The German Navy, the โ€œBundesmarine commissioned them on 1.9.1961 as FL 9 to FL11 and were used by Marinefliegergeschwader 5"naval aviation Squadron 5โ€ Until end of September 1975. the three were termed as air traffic control The fate of these three boats is a bit uncertain, one of these boats was in the process of being sold as NVG S1 as a North Sea supply boat, this deal fell through and the boat was sold to private owner in italy (no further record for this boat found) the other two boats are said to been scraped or de-commissioned , however these boats are quit properly the two that ended up in the service of the Spanish customs service as cutters, after they were confiscated when smuggling, I have tried to contact the Spanish about these boats but have not heard from them and presume they were scraped or sold in to private hands ( there is the suggestion that they were driven on rocks and sunk, no evidence found) D-boats of the South African air force/navy The two boats that were obtained by the south African air force in 1961 were originally known as R30 and R31 and they served under SAAF until 1969 when the unit was taken over by the south African navy and R30 became P1552 and R31 became P1551 these were changed again when holiday makers referred to the boats as PISS1 and PISS1 too R30 to P30 and R31 to P31. Both these boats were diffidently sunk R30 Lost off Saldanah Bay on 7 October 1988 after striking a reef off Danger Point. R31, near Cape Point, after she grounded through contaminated fuel issues There are somethings about these boats that strike me as odd, The originations that took over these boats, they donโ€™t like to mention the fact that these were ex-RAF or British boats, There is no record of the Spanish boats, it is said that they were sunk but no details are available except what is said on one form. I think I have done as much looking for information as I can, most of the bare facts are stated so thanks to all those web sites and forms that I have used and the pictures I have used I would like to thank to Dave M for the drawing And thanks to the marine craft branch museum for their help and for putting me in touch with Mr Rick Mortby who built the museums model of the D boat And a big thank you to Rick Mortby for the scale drawing and for his trust. And to Dr Christian Ostersehlte historian for Lurssen shipbuilders for the pictures of my Fathers boat D2763 and now I can start the building of the model D boat
    7 years ago by teejay
    Place
    days to sail
    HI and welcome to MMBG. You will need public liability and permission from East Lindsey Council before you can sail with us. it is very easy to obtain PL ins. by joining The Model Power Boat Assn. Send your membership card with covering letter to the council, bring your membership card and council letter to us for confirmation of your membership. Very easy and I can supply you with forms if you wish. . Suggest you phone me for a chat 01507 475946. Regards Victor๐Ÿ‘
    7 years ago by HoweGY177
    Forum
    What type of wire?
    Hi Nick, Servos & signal leads For these I use the twisted cable, pic 1. Especially if I need to extend a servo cable. Twisting the wires together helps to reduce interference. The interference current induced in one wire is suppressed by the wire next to it ๐Ÿ˜Š This is the principle used in high quality phone and LAN cables. Of course you can twist wires together yourself if you want. Clamp one end in the vice, the other ends in your hand-drill and away you go. Drive batter - ESC - motor- Rules of thumb For these I use cable from the motor trade. Make sure it is rated to handle the motor current you expect under normal running AND NOT LESS THAN THE STALL CURRENT OR THE BATTERY MAX CURRENT RATING! I don't do hi speed racers so the hefty 300A stuff doesn't interest me. if you do then use the car battery cable size. Cross section of the copper wires ca 25 to 35square mm. Pic 2. For medium power, < 15 to 20A like most of my scale ships the 'standard' car cable with about 2.5 to 4mm square is enough. Pic 3. Above all: don't forget to fit a fuse (quick blow) in each motor supply lead, Rating less than the max stall current that you expect and/or just under the max current rating of the cable. in the drive battery lead put a fuse (not quick blow!) rating to match the total max load you expect under 'normal' running; i.e.just above your total load but always less than the max discharge rate of the battery (esp. for LiPos!) or the wire mac rating. The quick blow fuses on the motors will blow first if a motor stalls, still leaving you with some power & control. Esp in twin shaft boats, you can limp home on one engine ๐Ÿ‘ On singles, time to take your socks off and join the ducks! ๐Ÿ˜‰ Odds and ends - low power So called signal cable or test-lead cable from hobby electronic shops with conductor cross section area of 0.75 mm square is enough. it copes with an Amp or 2 with no problem. General, make sure all connections are clean and tight, use gold plated connectors for all hi current wires, batt, ESC, motors. Hope this helps a bit. Cheers Doug ๐Ÿ˜Ž
    7 years ago by RNinMunich
    Response
    Bluebird K7
    I see that's a battery charger. I was thinking about a 12v
    power supply
    box I have. Can this be done from any lipo battery charger. I don't want to kill my one by doing something that it wouldn't like. it's an Elysium LX60B.
    7 years ago by BOATSHED
    Blog
    Bluebird K7
    Hot wire foam cutter: I started off by watching just about every video on YouTube on the subject. I then bought a few meters of 0.25mm NiChrome wire. At first I thought I'd just need a vertical bench top cutter. An unwanted shelf was liberated from a kitchen unit to use as the base, a couple of 2x1's were screwed underneath to give clearance for the wire connection. A piece of MDF was used for the upper arm. To give some adjustment underneath a block of wood with a screw in one end for the wire to wrap around was screwed to the base in just one position so the block could pivot. I drilled a clearance hole in the end of the upper arm for a long bolt & put a small slot in the end of the bolt to wrap the wire around, a washer and spring were used to give the wire some tension. When the wire heats up it expands so you need something to maintain the tension. Wrap the NiChrome wire on the screw underneath, put it through a hole cunningly placed in line in the base & up to the slot in the bolt in the upper arm, compressing the spring at the same time. Now that's all sorted get 2 pieces of normal wire, attach one to the screw underneath & one to the bolt on top. This is the bit where I found conflicting information on YouTube, people used all sorts of different things to power their cutters, batteries, pc power supplies & resistors, model railway power supplies, laptop chargers etc etc, everyone recommend different voltages & amperages. Luckily my Lipo charger can be sued as a
    power supply
    so I started messing with volt/amp settings, I didn't want the wire to glow red as that's too hot, I ended up using 10 volts & 2 amps, it works a treat. Unfortunately this cutter does have its limitations, throat depth etc. I decided I needed a hand held cutter, going off what I'd learned from the bench cutter this was a doddle. 2 pieces of 7mm steel bar 300mm long, 2mm hole in each end. 1 piece of 30mm square pine for the handle, 8mm hole through each end. Smack bars through holes in handle, get 2 pieces of normal wire, attach one to each hole at handle end, I just twisted them on & taped everything over. Now here's the trick with the other end, when you attach the NiChrome wire make sure you squeeze the bars together a little to give the tension, attach the other ends of the wires to the
    power supply
    & away you go. Like any tool I guess you get better with practice, lol Cheers Wayne
    7 years ago by Midlife306
    Forum
    Battery problems
    Hi Patto, forget the 'watt meter' and consequent P=IV -> I=p/V conversions! What you need to measure is the actual current drawn, especially the stall current, if you can manage that without getting any fingers chopped off ๐Ÿ˜ก On the lake anything can choke the prop so just testing 'free running' is not the whole answer. Sounds to me simply that your setup is drawing so much current that any battery or accu will go flat in a few minutes. Your example of a 5300mAH (i.e. 5.3AH) means that in perfect (!) condition, fully charged and almost zero internal resistance (int. cell resistance wastes power so buy the best quality you can possibly afford) it can theoretically supply 5.3 Amps for 1 hour. or 53 Amps for ~ 6 minutes (1/10 hour). and so no. LiPos with C values of 130 sound great BUT the discharge C value is related to the AH rating. So taking your example of 5300mAH = 5.3 Ah 130C = 130x5.3 = 689Amps! The Accu would supply that for ~ 27 seconds before departing to the great recycling centre in the sky! if you ever decide to try such an experiment PLEASE let me know in advance and I'll fly over the record the event for posterity ๐Ÿ˜‰ Seriously though folks: I can't comment on the prop/motor setup, one of my weaknesses - I always check my stalled motor current draw with an ammeter before selecting the ESC - but as an electronics engineer I do have some idea about power supplies and circuit requirements etc. Can't imagine that your setup exceeded the 160A (short term remember!) rating of the ESC so that seems to be faulty, but you still need to find out what current your setup will draw under severe load i.e. stall. If just holding the boat cause blow ups then something else is fundamentally wrong ๐Ÿค” Bit long-winded perhaps, much of the above makes sense but not the whole story, time to cut to the chase I thought. MEASURE THE CURRENT! Good luck. Doug ๐Ÿ˜Ž By the way the above comments about lead acid & hi current are OK. They are more useful for long term supply of low to medium currents. I still use them in some larger scale models (~ 1.5metre naval ships) as they provide useful ballast (i.e. payload) instead of JUST ballast! The 20HR of your lead acids refers to the Hourly charge Rate, i.e 1/20 of the capacity in AH, in your case 7/20 = 0.35A or 350mA.
    7 years ago by RNinMunich
    Forum
    brushless motor for a aerokits sea commander
    Hi Adijohn Welcome to the site. You can search the site for Sea Commander and will find how others have progressed with their builds. Regarding brushless I would expect a 35mm outrunner to be a suitable size with a prop of the same diameter and direct drive. The entry level
    power supply
    would be a NiMh battery of about 5000mAhr at 9.6 to 12v. if you really want the speed and endurance then LiPo is the best but does cost more and needs correct handling both when sailing and especially when charging. Brushless motors have kv ratings which indicate the free load speed per volt, so for an 800Kv motor at 10v = 8000revs (it will be less under load). They also have a wattage limit which is the product of the voltage times the amps, so for 10v at 20 amps this is 200 watts. if you exceed this the motor will overheat and fail. The ESC also has a max amp rating and best practice suggests this is twice the expected running current. You can buy a wattmeter to measure current and watts. There are many suppliers but have a look at http://stores.ebay.co.uk/Component-Shop?_trksid=p2047675.l2563. Hope this helps and if you like my response please tick the like box to help others find the post. Good luck and please post details of your build. Dave
    7 years ago by Dave M
    Blog
    Navigation lights and circuitry
    The white metal fittings for the port and starboard navigation lights were hollowed out with a burr in a Dremel tool and a small hole made for the LED lens to go through. After the wiring was soldered onto the LEDโ€™s and tested they were set into the fittings with some epoxy. I have pre-drilled the cabin roof and sides for all the fittings and thereโ€™s enough wire on each to go to the supply and switching circuit board that will be in the cabin. All of the lighting, including the searchlight, is switched by R/C so I made a power distribution and switching circuit from โ€˜Veroboardโ€™, my favourite prototyping tool for circuit development. Following my initial drawing of the lighting circuits I laid out the component positions and cut the Veroboard tracks to suit. Each LED is fed through a separate correctly rated current limiting resistor. One switched circuit controls the three navigation lights and the mast light and a separate switched circuit activates the searchlight. I included a spare position on the first circuit just in case I found justification to fit the mysterious stern navigation light that appears in photographs of the 93 boat, research into this has led to a bit of a dead end but nevertheless itโ€™s good to have the capacity to add another light elsewhere if necessary, perhaps the cabin interior, without too much re-wiring. The large ceramic resistor is for the searchlight LED, it only needs to be a 2watt type but I couldnโ€™t find a 3R9 resistor rated at less than 3watts in my bits box, itโ€™ll do the job OK but it looks disproportionally large compared to itโ€™s ยผ watt neighbours. Both lighting circuits are switched separately by R/C switches from Hobbyking, these Turnigy receiver controlled switches are rated at 30v 10A max so they are capable of some heavy switching if required so my little lighting circuits present no problems for them. One important consideration is that the negative supply to the lighting and the negative supply to the receiver have to be bridged for the switches to operate correctly, and this clearly explained in the instruction that come with the switches. The Veroboard has pins soldered into it for the wiring connections, all will be soldered and insulated and the board installed in the forward cabin, Iโ€™ll also include a separate charge/operate switch for the battery supply close by. Everything has been tested on the bench and all works as intended, as another will attest, itโ€™s advisable not to do this on the lounge table in case of misplaced confidence in electrical design ๐Ÿ˜œ
    7 years ago by robbob
    Blog
    The wheelhouse navigation light.
    While the paint is drying on the hull thereโ€™s time to continue working on more of the white metal fittings. The body of the small navigation light on the wheelhouse roof is just big enough to set a small 3mm blue LED into so I started hollowing it out with a fine drill bit in a pin drill. The technique is to start with a small bit and by drilling one or two turns at a time and the backing the drill out to remove the swarf, this ensures that the bit does not jam in the very soft white metal, and then gradually increasing the bit size to the required diameter for the 3mm LED. The wire for the LED was taken from a miniature transformer from a defunct
    power supply
    , this tinned copper wire is very fine and is insulated with enamel. The legs of the LED were trimmed as short as possible and the wire soldered to each and insulated with some fine heat shrink, then the pair of wires were passed through some more heat shrink to form the connection cable and shrunk down. The base of the LED was also filed down slightly to reduce itโ€™s diameter for a snug fit in the body of the fitting. After a quick test with a battery and dropper resistor the LED was epoxied into the body. Before painting the LED was โ€˜frostedโ€™ with a fine abrasive and the body cleaned up ready for paint. I used some Humbrol โ€˜Maskolโ€™ on the LED before spraying with some white gloss.
    7 years ago by robbob
    Response
    power supply
    (temporary) for the charger.
    Hi Frank. Like you, I'm just getting back into it after long absence and I am having great fun and enjoying the build immensely ๐Ÿ˜ Plenty more posting to come. Robbob
    8 years ago by robbob
    Response
    power supply
    (temporary) for the charger.
    Just wanted to thank you for posting all the valuable information on your build. I'm just getting back into the hobby after too many years away and appreciate the construction details that you include. it certainly appears that suppliers and craftsman in the UK are much more plentiful and involved in the hobby than I have found here in the US to date. I just started a Blue Jacket lobster boat to get my feet wet again but have my eye on a Speedline or Model Slipway Tamar Class Life Boat. Looking forward to more posts! Frank
    8 years ago by ffkjr


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