Ideally the centre of the weight needs to be near the middle of the boat. The original plan looked OK, maybe it required the batteries a little further back. The whole propulsion system did look a bit heavy for the boat.
"But, Mousie, thou art no thy-lane, In proving foresight may be vain; The best-laid schemes o' mice an' men Gang aft agley, An' lea'e us nought but grief an' pain, For promis'd joy!" Poor little homeless mouse 😭 squeak squeak! Your pump sounds like one intended for a small fountain. Look for one which is specced as 'Self priming'. Car windscreen washer pumps from the scrap yard do the job, most need 12V though. Graupner & Co do some small 6V jobs. Next time plasti-card for the superstructure!? Cheers, Doug 😎 Oh, and for the rest of us Sassenachs amongst us, the modern English version- "But Mouse, you are not alone, In proving foresight may be vain: The best laid schemes of mice and men Go often askew, And leave us nothing but grief and pain, For promised joy!"
Hi Pete, welcome er Home?😉 I'm not too surprised at your results with the new LiPos. That's exactly why it is recommended to put new LiPos through about min 6 max 10 charge / discharge cycles to 'condition' them, i.e. get 'em used to their working life😉 I'm not surprised at the short run times either. I seem to recall you have two hefty motors in your boat! Let's say (for simplicity) the motors draw 1.8A each. Therefore one motor would (theoretically!) run max 1 hour on a fully charged 1800mAh (1.8Ah) battery. Two such motors only half an hour etc etc. If (more realistically) they draw 10A together (probably more!) then they can theoretically run at that current for 0.18h or 10.8 minutes on a fully charged battery. QED. Theoretically cos you don't want to empty the battery and run it into 'Deep Discharge', i.e. less than MINIMUM 2.7V per cell. They don't like that and get stroppy; don't charge properly or worse 😲 You get the drift! 😉 If there's a danger of the river freezing over - you've got 4 months to build an Ice Breaker😁😁So get cracking😉 Cheers, Doug 😎
Well, best laid plans and all that. Things have not gone too well. I managed to transport the boat in pieces to Hungary as planned. That is where the plans changed slightly. The plan was to have a trial on the river by the end of my holiday. I was rudely interupted by beautiful weather so I spent a lot of time in the river myself instead. I have started to assemble the superstructure and completed the radar, which turns rather realistically when under power. I have added coloured LED`s to the navigation lights. I have mostly completed the painting and laquering. I assembled the hand rails but still have to paint them. I started to look into the electrics but had to stop when I found that the pump I purchased was not suitable for purpose. I put the pump under test and it only appears to work if fully submerged. Not really useful for a boat. I will search for a replacement.🤔 Just a small note, I have now found that the superstructure has warped slightly during painting. I fitted it really closely before painting but now it has twisted slightly. Very disappointed but never mind.😤 As I am now home until Christmas, there will be no further progress until then. I may not be able to trial until April as our river is often frozen at Christmas. Well I could not help myself and bought another kit. This next one is different and should be easier. It will be a Pilots boat. At the same time, I will now continue with the PTB refurbishment.🤓
Hi Doug and all. Delay in answering your post as for some reason, my phone was useless on the internet. I did not see your post about checking the capacity percentage until I returned home, so that is why in April my checks were not complete. On my return to Hungary a couple of weeks ago, I checked the batteries and they were both at 3.85 volts per cell and at 51% capacity. When they were new, they were at 31% capacity. My new smaller batteries were also at 30% capacity and when I left on a storage charge, they are also at around 50%. The new, lighter 4S batteries are 1800mAh. On the first full charge they only gave me 89% capacity. I used them both, unfortunately they lasted about 6 minutes each, and recharged. This time they charged to 99% and lasted 10 minutes. Hopefully they get a little better after a few uses. I am now back in England and when I left, all of the batteries were at around 3.86 volts per cell an 50% capacity. I will check again at Christmas but I will have to see if the Danube freezes to see if I can use the boats then or not.😉
[Score: 8/10] 46" Huntsman Single Propellor (2 Blade S Type 55mm) Direct Drive to a Gartt 1200KV (2 Blade S Type) Powered by LiPoly (14.8v) 5Amp/h Batteries - Comments: Great fun boat, really fast on 3 x 4s batteries in parallel
[Score: 5/10] 6"/1000g Huntsman Capable of 6mph and a runtime of 10mins Twin Propellors (4 Blade 20mm) Direct Drive Powered by LiPoly (7.4v) Batteries - Comments: This really is a build project, it is hardly out of the box. It will eventually grace the starboard side davits on Bulldog. However she shall be a fully working boat in her own right, a spin off from the Diana Challenge in a boat mag years ago. More when I get a whole lot more done
[Score: 8/10] 48"/12000g HMS Bulldog Capable of 4mph and a runtime of 120mins Twin Propellors (3 Blade 40mm) Direct Drive Powered by Lead Acid (6v) 12Amp/h Batteries Controlled Through Action Electronics P94 ESC - Comments: Metcalfe Kit at 1/48 She is has fine lines and looks well on the water. She handles reasonably well with independent control on each shaft given her length and the amount of superstructure too. She has direct drive on each shaft and need a load of ballast in the stern to keep the props well in the water otherwise she will capitate quite dramatically Running 2 x 12 Amp Hour lead acids she has a great run time, helped by her hull lines, she will carry her way for quite a distance, so yo need to keep your wits about you on a busy pond! She is an ongoing project / refit with new davits and ships boats to be added.
[Score: 8/10] 35"/11000g Yorkshireman Capable of 4mph and a runtime of 120mins Twin Propellors (4 Blade 50mm) Belt Powered by Lead Acid (6v) 14Amp/h Batteries Controlled Through Action Electronics P94 ESC - Comments: Model Slipway kit, with the incorrect wheelhouse windows, may change them one day when I have time on my hands, i do wish!! Been refitted with a Bow Thruster and up rated batteries from 2 x 12 Amp Hour to 2 x 14 Amp to give a better run time. Fan cooling added t the main motors. She runs well and I am slowly mastering the slow speed tight manoeuvring that twin screws on independent control and a bow thruster can give. A proper "Little" Big Ship that looks the part.
[Score: 6/10] 34"/10000g Maggie M Capable of 3mph and a runtime of 120mins Single Propellor (4 Blade 50mm) Direct Drive Powered by Lead Acid (6v) 12Amp/h Batteries - Comments: A Model Slipway Kit Built by my late father in law, Frank Ballard Runs well, handles Ok with its Becker Rudder and Kort Nozzle. Maybe time for a refit
I took my Emma out for a second "real" water voyage, tethered of course. Overall I am pleased with my progress. I need a more powerful servo to manage the sails and my rudder mechanism needs to be reworked so that it doesn't bind-up short when tacking starboard. https://youtu.be/_IXdwBZyCqE