Added a 60A ESC of Chinese origin, improved waterproofing, and modified the rudder water pickup. Repainted trim tab extension as while it sat in the test tank (AKA the bath) the water got into the wood and split the paint work car spray paint not as water proof as I had hoped. On the test I found it was pulling over 40Amps which is not what I want as this is a race boat with limited battery capacity so cut down propeller by filling of the lagging edge of the prop via a drimmel and a file, so now pulls under 30A at full throttle. At the pond I will check current and prop-sizes.
Well Martin, its their loss. I try to make everything except the electrics. I suppose I'm lucky in being a retired prototype engineer, with my own machines and space to work. These days I am restoring more than building, I find it more challenging. Spotted a vintage boat in antique shop today, it had diesel marine power and valve and relay control system with a strange adjustable korts nozzle arrangement. I am trying to get the wife to let me buy it. Cheers Colin.
😲 Another one for the 'Woodies'? "A former city employee in the Fukushima prefecture town of Koriyama has built a 4-meter (13-ft) long canoe from thousands of used disposable chopsticks recovered from the city hall cafeteria. Bothered that perfectly good wood was going to waste after a single use, Shuhei Ogawara -- whose job at city hall involved working with the local forestry industry -- spent the last two years of his career collecting used chopsticks from the cafeteria. An experienced canoe builder, Ogawara spent over 3 months gluing 7,382 chopsticks together into strips to form the canoe shell, to which he added a polyester resin coat. The canoe weighs about 30 kilograms (66 lbs), which is a bit heavier than an ordinary cedar canoe, but Ogawara is confident it will float. A launching ceremony is planned for May at nearby Lake Inawashiro." Three thousand six hundred and ninety-one number 29s with special flied lice please waiter! 😁😁 Oh yes, and a thousand gallons of Tsingtao to wash it down please 😋 http://pinktentacle.com/2008/04/canoe-made-from-disposable-c...
Hi Neville, Some intriguing suggestions here 😉 Good luck with the bicycle pump 😁 To be brutally frank! There are no short cuts to leak proofing an old wooden hull properly🤔 1 Internal deck / xyz mounting notwithstanding, if there's something wrong with the hull I want to know it so I can fix it - for good! If the probable source of the leak is hidden by some internal deck or mounting for xyz it has to come out! 2 To be honest, looking closely at your pics of the hull underside it's obvious she has had a few knocks. I would want to sand back, seal and repaint at least the red underside. Having so cleaned the hull off I would closely inspect all joints around the keel and chines and look for signs of previous water intrusion and soaking into to keel especially - potential delamination / capillary action through the keel or joints. When the hull is fully dried out and sanded back I would seal it with a couple of coats of Ezekote; the first coat you can thin with a little warm water so that it soaks into the wood better. Don't overdo it, about 10-20% water is enough. Second coat pure resin. If it looks 'patchy' give it another coat of pure resin. Dries so fast all this doesn't take long. Had to do all this on my fish cutter hull, Gina2 - see Blog! Was a sieve to begin with, afterwards she passed her ballast test with flying colours😊 See also my Sea Scout Jessica Blog. After that repeat your bath test, with ballasting to waterline, and KEEP AN EYE ON IT so you can see where any watter creeps in from!😉 If you take a short cut now you may well have to do it again (properly) some time😁 cheers, Doug 😎
New info I've never seen before. I wonder where robbob got that drawing! The 2 photos are fascinating as they show the angle metal screwed top the corners and chines all round. I can understand someone getting so into the details, but I have to stop myself. My natural inclination is to put everything in, but I want the model to look like it might have been given to me for my 11th Christmas, 55 years ago, so must stop short at what might have been a conscientious building effort by a proud Dad. I would, if I were a much younger chap and free to indulge, buy one of the 46" kits and do a real "number" on it, detail-wise, but I ain't. So a half decent finish is what I aim for. My main concern is finding the damned Taycol motor I rebuilt for it! I went to the drawer of early motors and it wasn't there! Panic!! Thanks for these new items of reference, robbob. Martin
OK, In chronological order😉 No! The Wattmeter has to be spliced into the cable between source (i.e. battery) and the load, ESC and motor. As shown in example 1 in the instruction extract above. BTW 1: if your Wattmeter comes with instructions in Chinese Unwinese (Misstoodifold in the under number 29s😁) then use the above. Despite it's name it's primary use to us is to tell us the current the motor draws so we can select appropriate fuses. It will also tell you the mAh you've taken out of the battery, or put in when on charge. As far as I'm concerned the actual Watt measurement is relatively useless, except perhaps for 'Bragging Rights' 😁 Speccing the ESC should be done by checking the motor current specs and adding a good margin for safety. If no specs available use the Wattmeter to tell you the current drawn at full voltage from a DC source. If possible under load in the bath. Hang on tight😲 That only works for BRUSHED motors of course! Then use an ESC capable of twice the measured current. BTW 2; if you want to use your 27 / 40Mhz TXs you will definitely need the suppression capacitors on the motors, despite the partial damping effect of the rectifier, to reduce interference to your own radio. Fuses; I'll put 15s in to be on the safe side. If the Wattmeter / Ammeter measurements indicate less than 10A max then change fuses to10A and use a 20A ESC so it has some reserve. Or is operating within it's true capacity😉 Cheers, Doug 😎
I found that Chinese 5 spice powder worked fairly well, but getting an even coating is difficult, especially where it's always windy like here. I shall be making the davit and hook mechanisms in brass and getting them cast. There are none available as far as I know. Martin
yes Doug, and when the computer and printer wont do what you want and your tax return or companies house documents are due urgently but refuse to go through and you tear your hair out and swear violently , you wish life was much simpler ! I thought these machines were supposed to help us. When i was a trainee engineer they told us that in the future we would all have so much leisure time because machines would be doing all the work !!! Got that wrong didnt they !!!
My Albion was scratch built by my friend - Brian. He also built the Chinese Junk some of you will have seen posted on this site before. A very talented and lovely man. Picture again postedfor you to see. Enjoy.
OK John, just warn me when you start turning blue 😁 Got a bit bogged down with other snags! At least we managed to clear up Martin's little mystery 😉 More velly soon (must be using too much Chinese stuff😊)
Evenin' Hammer, For smaller milling bits have a look at the Proxxon range. From them I have bits down to 1mm 😊 Those are what I use for milling depressions and slots into shafts for securing keys or grub screws. Not cheap but they do the job time and time again. That's what I used on the new shaft for my Sea Scout, and will use on the prop shaft that Martin made for me for Gina 2👍 Quality has it's price, especially in mini machine tools 😉 I don't have a rotary table either, so the 'banana' slots I make with a diamond file like you do👍 Simple machining ... OK, but conceiving, designing and creating such magnificent machines as you do ...... way beyond the capabilities of a simple electronic engineer, Hat Off Sir 👍👍👍 looking forward to your next steps with great anticipation. Cheers, Doug 😎 Amazing coincidence with the name Gina! 😊 Greetings to her as well😉
We should live so long Ed 😉 I may have the machines necessary to make a steam engine, but I sure don't have the expertise necessary🤔, like Hammer 👍 for instance does have! Anyone out there making mini marine diesels???? Cheers, Doug 😎
As promised (or threatened?😁) stage two of the hull work and thoughts on motorisation. The hull was sprayed with two coats of grey primer/filler. Pic1. As usual this showed up the remaining imperfections (pics 2 & 3), but I'm not going to worry about them until I've got prop shaft tube and rudder stock sorted out and permanently fitted 😉 After my attempts to make and thread a 3mm prop shaft went awry Martin (Westway the Mechanicals Master👍) stepped in and made me a decent one complete with a bushed stuffing tube 👍 Vielen Dank Meister😊 I did however manage to make a 4mm to 3mm reducer so that I could fit a Rabeosch 35mm prop as seen in pics 2 & 3. The tube and shaft from Martin, arrived Saturday an' he only made it on Monday😊, have been dry fitted so that I can start setting up the gears, necessary to bring the drive down to the prop shaft fitted very low down in the hull, and motor mount. Pic 4. Motorisation: (Remember folks - this kit was designed and built as a static model!) I want to use the old 1950s Taycol Target motor which my Dad originally fitted in the Sea Scout which I have renovated and upgraded to brushless. See Build blog 'Sea Scout - Jessica' Many of you will know that the Taycol motors were field coil motors, meaning that they have no permanent magnet around the rotor coil, and thus reversing the battery connections to the brushes had no effect on the direction of rotation, as this simply reversed the magnetic fields of both stator and rotor coils🤔 To counteract this so that the motor could be used in both forward and reverse with a conventional brushed ESC I modified the motor slightly (separated the two coils) and built a simple converter board to connect it to the ESC. Again see the Sea Scout blog for the details of the conversion. Basically; once the field coil and brush-gear (rotor coil) have been separated a simple diode bridge can be used to apply the output of the ESC to the motor. This enables the reversal of EITHER field OR rotor coil polarity, depending on how you connect the converter to the motor. Thus reversing the direction of rotation of the motor. Beneficial side effect is that the diodes also suppress the commutator sparking😊 In my case, with the Taycol Target, I also cleaned, flattened and polished the commutator. Thus significantly reducing the potential for spark generation in the first place! A peculiarity of the Taycol motors is that they all use metal brushes, pressed phosphor bronze strip, so they need oiling! DO NOT oil conventional brushed motors with carbon brushes unless the brushes are exchangeable or you want to have to buy a new motor!!!!! Pics 5 & 6 show the proposed position of the Taycol in Gina 2 and pic 7 the prototype converter board I knocked up to test the motor, together with a Graupner Navy V30R Marine Brushed ESC. Details and results in the Sea Scout blog, including video of the sparks and oscilloscope pics of the drive waveforms before and after conversion! The latter showing the spark suppression effect of the converter😊 Some samples attached - last 3 pics. Pic 8 pic shows a more compact version of the converter, one of a few types I'm doing for Martin's various Taycols as a trade for the prop shaft he made for me and some useful material he sent. Thanks mate👍 Next steps will be 1) mounting the gears correctly on the shafts, requiring the manufacture of a 3/32" to 4mm adaptor and a 1/8" to 4mm adaptor, and keying them to the shafts - Hooray for mini milling machines 😉 2) manufacturing bushed end plates to hold the gears in place, 3) fitting the motor mounting platform. I'll probably borrow from my experiences of real shipbuilding and do this as a suspended 'false floor', i.e. mounted on stiff springs to enable adjustments to optimise the gearing mesh! On real naval ships this is done to improve shock resistance and to minimise engine noise / vibration conduction to the hull, thus significantly reducing the acoustic signature of the ship. Not that I'm tooo worried about being torpedoed 😁 Worth a try😉 Pic 9 shows the cleaned up and renovated Taycol Target motor. Pic 10 shows the drive waveform complete with sparks before modification.🤔 Pic 11 the cleaned 'forward' waveform with the converter board. Pic 12 the cleaned 'reverse' waveform, no suppression capacitors needed 😉 More soon folks, Cheers, Doug 😎 PS Along the way a new keel was fitted as can be seen in pics 1 to 3. The original builder had 'buried' the keel in the hull planking! 😲