All donations are securely managed through PayPal. Amounts donated are not published online.
Many thanks for your kind support.
Model Boats Website Team
October 2018: 5 people September 2018: 13 people August 2018: 5 people July 2018: 8 people June 2018: 8 people May 2018: 7 people April 2018: 24 people March 2018: 13 people February 2018: 8 people January 2018: 9 people
Thanks Doug but can't see a current rating. Just volts in and out. I thought about 10 Ohms but your numbers are right . Is 5 amps a bit high. It's only for up to 4 Nimh AA cells after all or are you playing safe? Sorry I don't know how I missed previous answers. A similar one shows 400 Mah. |But thinking back I think the original was 7.2 v @w250 Mah. I only think though.
Your more than welcome TJ. Re paragraphs etc; was a well meant 'Word to the Wise', just to make your interesting contributions easier to read. 😉 Keep up the good work👍 Which configuration did you decide on in the end? On my single screw boats, like my Sea Scout, I tend to just use the BEC from the ESC and no separate RX battery. On my multi screw ships, the majority actually, from two to four screws (PTB to HMS Belfast cruiser) I always use a separate RX battery. On the basis that I reckon that the drive battery already has enough to do 😉 So I use 4.8 or 6V NiMh batteries of around 1500 to 2000mAh. Always put a switch between the batt and the RX. Also a switch and a fuse, approx 5A lower than the ESC max current rating, between the drive battery and the ESC(s). All the best, Doug 😎
Hi TJ, RE: RX battery. Any 4 or 5 cell (4.8 or 6V) NiMh of 1000mAh up will do. Use the biggest one you can without upsetting the boat's trim or reducing it's performance / planing etc. BUT: don't forget to disconnect the red wires between your ESCs and RX to disconnect the BECs in the mTroniks speed controllers!!! Also check that your RX and mixer module etc can handle 6V+! If not use the 4 cell pack. A fully charged NiMh will be significantly above 6V. Some modules; e.g. Action Electronics / Component Shop don't like that 😡 Alternatives are, esp if you need to save weight, 1 use ONE of the red BEC leads from ESC to RX, e.g. the centre one, and disconnect the other two, 2 Use a separate 5V UBEC module to syphon power off the drive battery for the RX, AND disconnect all three red BEC wires from the ESCs. Cheers, Doug 😎
Revell model at stern you see a small servo with micro switch for the Ram whooper sound module. Pic with upper deck on side shows speaker and electronics with 9volt battery power. Moving forward Harbor Models small 6 volt smoker, 3000 nimh 6 volt battery with 2 connectors powers smoker fan and main motor from ESC.
[Score: 9/10] 39"/3400g Sir Kay (T241) Capable of 3mph and a runtime of 30mins Single Propellor (3 Blade 50mm) Geared to a MFA Geared 2.5:1 (3 Blade) Powered by NiMH (7.2v) 3Amp/h Batteries Controlled Through Mtroniks (5Amps) ESC - Comments: This is my Sir Kay (T241) - Round Table Class Minesweeper. It is from the Caldercraft range and I was fortunate to recently acquire it - I would have much preferred to have built it but couldn't miss the opportunity of it being given to me by an old retiring modeller. It just needed new RC throughout, a good clean, a tidy up and some fresh paint here and there plus a bit of rigging renewal. Not tried it in the water yet but will do tomorrow at our Club meet. Tried it today and it sailed really well, stable and sits perfectly on the water and one 3000mA 7.2 NiMH battery lasted all afternoon - so pleased with it.
Doug a quick one for you I've got a wall wart with a blown / burnt resistor. The rest is working fine and I would like to replace the resistor and put back into use with the model it belongs to. I can't read the res as its burnt black (output leads got shorted.) It's the last one in the circuit ( output lead ) Voltage up to it is 15v. It is to charge 7.4v Ncads/ Nimhs AA/AAA packs. I can't work out what the value should be. Should be simples for you if you'd be so kind as to do the maths for me. I'll luv ya forever if you do. Not literally of course but ye know warrimean. Regards John👍 No comments like ducky etc please. Oh yes remember your remarks re our local pubs? The owner of our nearest the STAR ( ex plough Still got one on roof of main windows) rang our bell. He'd seen Marg go off in an ambulance 2 days on the trot and wanted to know if he could help.( We were customers now and again) He brought a wine for Marg and a nice flask of bitter each for Ant and I. Luvverly. He stayed about 2 hours nattering and when he left he said ring him if we needed help any time. We had the same offer from a young chap who helped Marg up the path too with a mate. Our adjoining neighbour looked after their shopping. Starting to see some signs of neighbourliness again it seems.👍😁.
[Score: 5/10] 20"/600g Elke HF 408 Capable of 2mph Single Propellor (3 Blade) Direct Drive to a 6v (3 Blade) Powered by NiMH (7.2v) Batteries - Comments: This is a restoration project - my first radio control boat 'Elke', is a small fishing boat with plastic hull, a Graupner kit, purchased in Germany when I was serving in the Army there in 1974. I am restoring it for my grandson. It used to be a good runner with a 6v battery, small electric motor, two servos, one wired so it could move boat in reverse as well as forward. A good little sailor, light in weight and a good pond model. Had to be careful of wave height. Anyway, it has been in the garage for 40 years now so much to do. The inside is a bit of a mess and everything has a layer of dust. I will fit a speed controller and NiMH battery. But nothing too difficult so hope to have it finished for Christmas.
I am using the short thread glow plug. It turns out that glow plugs have a very fine thread. I think it is 1/4" x 40, National Extra Fine. Barrel is just K&S brass stacked and soldered up a few layers thick. I light it with two NimH for 2.4V and a micro switch stuck on a servo. You need to let it off quickly or it will burn up the glow plug. One battery seemed a little weak. I know it will work well for depth charge throwers. Depth charges themselves will just be lost. It takes a bit of time to reload. I never tried it, but someone suggested using premade ammo made from paper soda straws. It might work. You have to be careful with this!
Like many people, I originally built a Model Slipway 1:16 Tamar with the recommended brushed motors. Most of us switched to brushless motors for a number of reasons... 1. short battery duration using NiMHs, or an SLA with brushed. 2. These ALBs have an on-Service speed of 25+ knots and for scale speed, only brushless motors and LiPos can sensibly provide the power and duration. Model Slipway converted their demonstrator to brushless.
OK, found some! https://www.ebay.com/itm/8pcs-JUGEE-3000mWh-1-5V-rechargeabl... Interesting that they all quote mWh instead of mAh! I.e. energy instead of capacity! Power being V x I (Amps) divide the mWh rating by the nominal voltage to get an approximation of the capacity in mAh. Saves integrating across the varying voltage during a discharge cycle, i.e.'On Load' 😉 Thus these 3000mWh cells seem to have a capacity of around 1800mAh. Which is considerably less than the typical 2500mAh of an alkaline or NiMh AA cell. Also, to produce the output voltage of 1.5V from 3.7V Lithium chemistry the cells have an internal voltage regulator, which also must consume some power, albeit miniscule. Something else which can go wrong🤔 Summary; yer pays yer money and takes yer choice! Seem rather expensive to me for what they deliver. Depends what you want to use them for. Might be useful in my Sony camera but I wouldn't use them for any high current load in a model. OK perhaps for LED lighting circuits which only need a few tens of mA. Here a list of battery types, sizes and chemistries for reference. https://www.wikiwand.com/en/List_of_battery_sizes#/overview Cheers, Doug 😎
Mornin' Ron, If you put the motor where the batteries are now - where will the batteries go? They weigh far more than the motor so moving them forward will push the CoG even further forward😲 Re shaft angle; as flat as you can get it for the size of prop you want to use. This is to reduce the forward rotation moment of the thrust which tends to push the bow down. The further back you fit the motor the larger the angle will inevitably become due to the space needed for the motor and mount! BTW: Why two NiMh batteries? I would be tempted to change the set up to a brushless and a single LiPo. This will significantly reduce the total weight as well👍 You did say the boat is 'a heavy model'! 😉 Doug 😎
Sorry but when you said 6v I assumed it was a SLA so your NiMh, must be a 5 cell as they come in multiples of 1.2v. So I agree the simplest solution is a Rx battery pack and disconnect the BEC supply. (May need to remove +ve wire from ESC(s) plug?)
Hi Will, Sounds good to me👍 I like the Action Electroncs stuff as well, have their dual ESC with rudder mixer which I want to try in my long thin destroyer to reduce the turning radius. Was misled about the SLA by a previous post🤔 Makes sense re the BEC which I believe is 5V 1.2A. I prefer a separate RX batt anyway😉 BUT: if you run a 6V NiMh down to 5.6V you are close to the Deep Discharge zone which will seriously damage the battery and drastically shorten it's life 😲 Threshold voltage is 1.0V per cell, so take erratic control as a warning that the battery is flat and come home soon! Look forward to your Sea Trials report. Cheers, Doug
Doug, The 6volt battery is currently an NiMh battery not an SLA. The problem was that according to Mtroniks the minimum voltage to the ESC to adequately run the BEC connection is 6volts. That is why I was getting erratic control when the battery voltage was 5.6 volts. The action speed controller will work 2-12 volts and I am going to use a separate receiver battery as suggested by Dave Milbourn just to make sure. Regards Will
hi Will, I agree with replacing the SLA. If you don't want to go LiPo cos of chargers etc etc how about a 5 cell 6V NiMh? much lighter than the SLA For the ESC switch to the Mtroniks Viper Marine Micro 10. That handles motors up to 550 can size, 10A motor limit, and runs off 4.8 to 12V 👍👍 I use these very happily on ships running 2 or 4 540s. A destroyer and a cruiser. Both about 54". http://www.mtroniks.net/prod/Boat-Speed-Controls/Viper-micro... You can get 'em about 5 quid cheaper here https://www.cornwallmodelboats.co.uk/acatalog/Mtroniks-marin... There are also 15 and 20A versions if you want to run both motors off one ESC 😉 Cheers, Doug 😎