All donations are securely managed through PayPal. Amounts donated are not published online.
Many thanks for your kind support.
Model Boats Website Team
January 2019: 14 people December 2018: 6 people November 2018: 11 people October 2018: 9 people September 2018: 13 people August 2018: 5 people July 2018: 8 people June 2018: 8 people May 2018: 7 people April 2018: 19 people
First time in the water and under power. to get the correct trim (ect) I built a test tank from ply and lined it with polythene. To stat with There were two 12V lead acid batteries and the weight of the two motors, she just simply sat there, even the props were above water. After approx 30lbs more weight the correct water line was reached, the white line on the hull follows the sheer line of the main deck and isn't the true water line. So with the two batteries hooked up in parallel, the 12V Proboat Speed controller and the two Duma 12V motors as can be seen quite a good performance.
49 Inch Perkasa fixed after burnout - Posted: 4 years ago by lesfac
Following burning out the motor by fouling the prop on a polythene bread wrapper I fitted a new 160 amp speed controller and got a bargain motor from Giant Shark. It Is an Emax GT4020 which cost about £14. I realised what a bargain It was and went back only to find Giant Shark have ceased trading. The video shows the boat running on a 4 cell Lipo, It goes a bit quicker on a 5 cell that I have. I am really sold on Lipo power as Dave said I would be. I have just ordered a 3 cell Lipo for my crash tender
This Is my M.F.A Tracker . When originally purchased It had the large and heavy 850 motors In It and old electronics , after a close call with a fire on board I decided to refit her out with modern Brushless motors and over rated Escs powered by Lipo's . Works out a 1/3 rd the weight 3 times the speed and run time over an hour . So a great result
Cheers Father , hope to get a film of Nam boat on soon 😀
VOSPER PERKASA 49 INCH KIT PART 2 - Posted: 4 years ago by lesfac
This video follows on from my earlier post. I changed to running on a 5 cell lipo (18.5 volts) and I am very pleased with the Improvement over 14.4 volts Nicads. (Edit sorry Nimh`s) I put this link Into my reply on my previous post but It didnt work as a hotlink so I am posting this. The boat Isnt quite flat out here due to the difficulty videoing and steering. Les
I don't know If this Is what may appeal to you In regards to a more detailed laser cut kit, but you might look Into It for a future build. Dumas [ U.S.] makes a nice 30 Inch laser cut Higgins boat that they describe In the Instructions as being a toy but It's well crafted and with a bit of creativity can be built Into a decent scale model suitable for radio control. I think your Vosper Is awesome. When you pour on the throttle It actually sports a rooster tail. Job well done mate.
Really motoring. The battery can be mounted anyway just make sure the leads are clear of the motor and remote from your radio wires. I suspect you will not be happy with the NiMh batteries. I am assuming they are NiMh as NiCads have not been available for some time. If they are NiCad then they must be nearing the end of their useful Life so another excuse to switch to LiPo. Glad to see you project successfully on the pond. If you Invest In a Wattmeter you will be able to tune your motor to the prop and achieve max speed and time on the water. Happy sailing Dave
Well Sods Law Rules. Took It to Cwmbran boating lake for Its 3rd sail on Sunday and It picked up a polythene bread wrapper around the prop which had the effect of causing the prop nut to tighten on the prop tube clamping the prop shaft and I fried the esc. I have ordered another esc and I am hoping the motor Is ok. A big thankyou to Cwmbrans duck feeders
HI Les What a bummer. Bread Is not good for wildlife and certainly not for props. Hopefully your motor should be OK as long as the wires are not burnt. If you have a multimeter you could check the Insulation between the shaft and each winding using the highest ohms reading. It should be high, If low chances are there Is an Internal short. A quick check (on a lower ohm reading) between windings should give similar results between every pair, again any variance may Indicate an Internal short. Dave
I am just building one of these on a wood hull, I notice you are running a single motor. Could you advise what motor you are using plus what prop please? Thanks Andy
VOSPER PERKASA 49 INCH KIT - Posted: 4 years ago by lesfac
This was a precedent 49 Inch kit that I made during last year. I wasn't at all Impressed with the kit. The precut plywood parts were cut with knife blade tools and the tools were obviously past their sell by date. The shapes were very poor. If I make another kit I will make a point of looking for a laser cut hit. Having said that I am pleased with the outcome.
lesfac, it Is looking great I am building the same boat powered by two 1400kv brushless motors & 90a esc powered by two 4c 5000 mah lipos It Is fast, I agree with you about the kit I find the balsa a pain to make up & paint, I have modified It a lot & bought Battlecraft fitting & armoury regards Bob
As Its a big boat I replaced some balsa with bits of pine as the balsa was very open grained and fury. I suppose It could have been treated In some way but the pine worked OK. The lockers were supposed to be made from balsa but same problem and I made them out of some bits of foamex that I happened to have. Sounds like yours will be a rocket ship. I have one brush less motor and power It with two 7.2 volt nimh In series to give 14.4 volts. The end bit of my video shows It flat out. Regards Les
You have made a good job and your skill and knowledge will have Improved. You may find that even a more recent Laser cut kit can be Improved! Looking and listening to the video the motor sounds slow for a brushless, what prop size have you used? Unlike brushed motors brushless can run better on smaller props. The kits from the 1960's era were as you say not cut to the tolerance of modern kits, but needed lots of fitting by the builder. We still had a large manual skilled trade In that period and schools and Tech Colleges taught the skillsets. Modern kits are made so precise that very little fetteleing Is required to put the pieces together. Looking forward to your next build. Dave
Dave I have been building models for over 50 years I learnt from my uncle who was a shipwright I served my time as a marine engineer and retired 5 years ago & took up the hobby In earnest, The props are 45mm brass 3 bladed I have tried X props but still prefer brass, I have started a new Perkasa build but still have Issues with balsa It just does not finish to a good standard I have a Coble & a R6M yacht that are nearly finished after that I have the plans for a WW2 landing craft regards Bob
HI Bob I should have realised you were not a novice from the finish on your model. Balsa Is quick and simple to work but yes the grain can be a real problem when painting. Sanding sealer Is a firm favourite to seal the grain and several coats with fine sanding between produces very good results. Problem Is It Is fragile and easily dents so a good paint finish can be easily spoilt. I use liteply or plasticard as both are resilient and take a good paint finish. Some use balsa with a very thin plasticard covering and the results give both a good finish and a very resilient surface. Regarding the prop I also use 3 blade brass and find they give a much more realistic wake. 45mm Is possibly a bit on the large size and you may find a 35 - 40mm allows the motor(s) to develop Its (their) max performance. The Coble sounds Interesting and the R6M must be quite a beast, sizewize. I looked at some landing craft for 1:32 scale tanks a the E Port show and was very Impressed with the detail modelled. Kind regards Dave
HI Dave, I make my own sealer & shellac and have tried every material you can Imagine, I have run the Perkasa on this set up for two years and It Is far too fast as It Is I have to keep It at half throttle any faster It would do an Anthea Turner ( If anyone remembers her )
if you ever want any plans a friend of mine does just about everything going he will even size them up for you (Email Removed - PM Only)
1400 x 11.1v lipo = 15.540 rpm x two 1400kv x 14.8v lipos = 20.720 rpm x two
I remember her. I have a part completed hull at this size and will complete at some time. They are fast we have several at both sizes In our club. Good to hear about the plans, used to use a local service but they were taken over and now have a minimum charge of £20 so unless I need several plans copying/enlarging Its a tad dear. I have the same problem with my Aerokits 34"crash tender. I eventually had to use my 6Ex Futaba set to reduce the stick throw. Even then I had to use a switch to reduce the rate even further before making a turn. Take care Dave
Dave this guy does not charge much I got the Coble plans sized up to 1.5 times & posted for £8 he Is a great bloke I have a spectrum 7 It hold 20 models It does half for my boats & half aircraft happy sailing Bob
I have just ordered a 5 cell lipo battery of 5000 mah and a lipo charger. This will boost the running voltage to 18.5 volts. I have a Maytech 80 amp speed controller and an EnerG C50-20 brushless motor running a Graupner 55mm 3 blade propeller. There have been no heat Issues at all with the current set up and I am reasonably happy with the top speed using the existing NiMh 14.4 volt set up but I am Interested to see how Lipos go and what the additional voltage will give me. Les
On lipos I have read something about programming the speed controller not to discharge the batteries below a certain point. The question that occurs to me Is can you prevent the boat shutting down In the middle of the lake? Les
HI Les You should not discharge LiPos below 3.3volts per cell. at best you will Irrepearably damage the battery If you allow this to happen and at worst the battery will become unstable and be at risk of explosion. The charger should have a small plug In addition to the main connector. This Is to allow for balanced charging, again to protect the cells from overcharge. Your ESC should allow you to set a cut off voltage (16.5v In your case) and reducing this may result In one or more cells dropping below 3.3 volts. Some ESCs allow you to set a reduced output when the battery voltage Is too low, giving you time to bring the model to the bank. I use a two way system that advises me of the Individual cell voltages whilst on the water so I can avoid stopping In the middle of the lake. There are also some cheap add on devices that flash lights and sound a siren to advise low voltage. A damaged LiPo often shows bulging of the soft plastic covering. Dave
Thanks Dave I understand the Importance of not discharging lipo's too much. However Ideally I would like to be able to run my boat on either the 14.4 volt nimh set up or the 5 Cell lipo battery that I have ordered. As you Indicated, I have ordered a warning device to attach to the lipo battery that will sound a buzzer at the low voltage point.
If I dont put a battery cut off voltage In the esc and rely on the warning buzzer, will this be ok? I am thinking It will allow me to run either set of batteries.
If I put the cut off voltage Into the esc at 16.5 volts for the lipo I Imagine the 14.4 nimh wont run at all. This would leave the only option of reprogramming the esc at every battery type change.
While hoping for a good Improvement on lipo I dont want to waste perfectly good nimh batteries
HI Les You are taking the correct steps for the LiPo. The buzzer will sound when the set voltage Is reached so will warn you to return to the bank. If you don't notice this and your ESC Is not programmed to cut/reduce the power you run the risk of over-discharge. The ESC will take whatever action you have programmed when the set voltage Is reached so this will not allow the use of batteries with different cut-off requirements. I can appreciate your problem and can't see a solution, other than your suggestion. Once you have experienced the benefits of LiPos I suspect you may find the NiMhs lack the performance and decide to upgrade by selling the NiMhs to a good home. If any other members are aware of a workable solution, please share your thoughts with Les.
Well I fitted the Lipo and tried It out and I am very happy with the performance. Its quite a step up from the nicads. The video link below shows how I fitted the battery and how the boat went. It Is plenty fast enough for my liking. In the video Its not flat out as I found It difficult to video It and steer at the same time. There was a funny situation with the esc though. I left everything the same as with the nicads and relied on the sensor to sound a buzzer. When I plugged the battery In the rudder worked Immediately but the motor would not run so I thought I had a problem but after a short while the motor started to work. I took the boat to the lake and had the same situation for a while. After the motor started working It ran faultlessly. I was listening for the buzzer to signal low voltage but the boat shut down. It responded enough to get It back to the bank and the buzzer was sounding now. I dont understand the delay In the motor waking up or how the esc shut the power down when I havnt programmed It to. It did shut down at 3.3 volts per cell. Anyway very happy performance wise and In view of the big Improvement I will probably go through the set up for lipo running now Heres the video link https://www.youtube.com/watch?v=dh0zhbRQQT8
HI Les Good to hear you have the LiPo working. You need to set your ESC to recognise the LiPo. When correctly set you should hear a series of beeps Including a sequence that Indicates the number of cells In your LiPo pack. I am assuming you have a fwd only ESC so the throttle stick needs to be pulled right down and the trimmer set to neutral when you switch on. Some ESCs require the Tx throttle setting set to nor or rev and refuse to set up correctly with the wrong setting. Unlike brushed you cannot always use the Tx to correct a wrong running prop. Its easy to correct by just swapping any two of the three wires to the motor. As the ESC shut down at 3.3v I suspect you have It configured for LiPo use as this Is the common default setting. The buzzer may not be loud enough to hear from a distance or was slower to recognize the low volt, you could try setting to a higher volt to give advance warning. At least your Esc allowed you to return to shore. Not looked at the video yet but am sure you will want to continue with LiPos. Cheers Dave
The bit I can't understand Is that I was running the boat on 14.4 volts. I did nothing yet It cut out on the lipo at 3.3 volts per cell which would equate to 16.5 volts. If It had been programmed to do this It wouldn't have worked at 14.4 volts. Its as If It had auto programmed Itself.
HI Les There are default settings In most ESCs and they change when you select a different type of battery. If you selected LiPo It recognised 5 cells and auto set a 3.3 v cut off. My latest LiPo 5000 suggests a cut of voltage of 3.4 volts so I suggest you look on the battery cover to see the recommendation. The higher power batteries are very low Internal resistance and I believe this Is why they suggest a higher cut off. So yes your observation Is correct