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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 😡 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 😉 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 🤔 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 😎 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.
So I have been doing some paint priming and still messing about with the outboard.. It now has the rudder dry fitted and it will not be seen above the waterline.. Most of the shaping is done now And I have cut out for access hatches to both to fit and get to the servo. The hatches I have got are semi waterproof and come off of some wet wipes. Now all the shapes are about right I will just carry on with a little more. And start looking about for the foam for the sponsons and some paints. This I am sure is going to be very light so with the electrics as low in the hull as possible and the foam tubes I have no Idea how much little ballast I will get away with...
I now have enough plastic to complete the Shamrock Police boat. thread here https://model-boats.com/forum/ building-related/27236 And Also now have some larger pieces seems these bits are scrap as well due to the fact they fell on the floor and nobody bothered to pick them up and just walked all over them. so they have little dents in them. That is no problem for me to fill as and when I need to. So having just made a small rhib for the Shamrock about 16 inches long I thought it would be nice to make a fully working one. So I started this one is 35 inches long without the sponsons. I have All the electrics for it already ( Hand me downs ) so no nothing to loose. So this could be the model that costs nothing to make and build. No Plans or drawings or templates and now under way. All constructed out of 2mm foam board plastic.. Held together with electrical insulating tape while the glue dried. I will have a bit of filling and sanding to do when it is a single solid piece. Now comes the part of working out some sort of rough scale for the completed hull. In the meanwhile forming the chines out of the same plastic but very thin strips. Not found any bright Orange paint yet but still looking . If all fails it will be a white rhib. I am thinking with the foam collar the weight of the electrics placed as low as I can get them I may need very little ballast As so far it is very light. Still as always another lets see how it turns out..
R.I.B completed, adding about another 1 oz to the vessel weight, also added the 4.5 oz as permanent ballast. Total model weight is now 156 oz. On review of many HMCC “Vigilant” pictures, note the top of the boot-topping can be almost coincident with the waterline. Decided the slight extra weight , beyond the 4.5 oz originally tried, will help raise the bow and have little effect on the stern draft, so left it as is. Sailed again in the portable pool and now consider the trim acceptable. The boot topping is visible for the full length of the hull; she sits very much like the full size vessel. Once the ice to leaves our local pond will see how well she performs in open water and what the run time will be. Have tried several approaches to making a R.I.B launch / recovery mechanism, but with little success. Seem to be able to either launch or recover using a single radio channel, but not both. Now decided to shelve this feature until inspiration strikes!
Hi Sonar. Mine arrived at 1.45 pm, well packed and just what I expected, as you say a bit of tidying up but nothing too involved. Of course, you know it has put the cat amongst the pigeons with "her in doors" !!! She took the delivery and said "Not another model boat" !!! Anyway, thanks very much. I have now got a nice little project to start when I get bored with the others !!! Cheers.😊 Ballast👍
I am pretty sure it uses a 10 inch propshaft but one with an oiler would be far better than the stainless steel ones. I used a small brushed motor and it is quite nippy with a platic two blade prop at 35mm and I think the total weight when ballast is fitted weights approx 3 to 3 1/2 kg
[Score: 5/10] 32" Exuberent DH 142 Single Propellor (3 Blade) Direct Drive to a Graupner 700 (3 Blade) Powered by Lead Acid (6v) Batteries - Comments: She is a model of the original boat which was lost with skipper March 23rd 1983 off Portland. I had been building the static model since she was launched in March 1981 then ceased build when the tragedy took place and took my friend, the skipper. I recently moved to Burnham on Sea and joined Sedgemoor Model Boat Club and I was inspired to proceed with the build as an RC Model. Wish me luck !!!👍😊 The original boat was a Cygnus GM32. The hull and wheelhouse mouldings were supplied by Cygnus Marine Newlyn, Cornwall, as was the hull for the model. The boat was self built in Dartmouth by the owner/skipper as a Crab Potter. On completion she fished the waters off Dartmouth Devon during the summer months and then off Weymouth during the winter where she was subsequently lost en route for Dartmouth loaded with pots to transfer fishing activities back to home waters. She was a marvellous little sea boat and performed well in rough conditions. It is still a mystery until this day why she floundered. I hope her memory and the Skippers will live on through my model.