Blog

Fitting sub decks and Sea Trials

The fore sub-deck is glued onto the bulkhead assembly, prior to fixing it into the hull. This is a straightforward operation, but some sanding of the sub deck is needed, particularly around the bow. With short strips of square balsa glued onto the hull sides between the deck beams, to support the edges of the foredeck, the whole unit was again dry fitted. Happy with the dry fit and armed with various clamps and clothes pegs, I glued the assembly into place. (Once again, apologies for the lack of photos as I did this before deciding on doing the blog). Before fitting the aft sub-deck, I cut out an opening to get to the tiller if necessary. The opening will be disguised later in the build. Sea Trials. I decided on batteries, as the weight would go a long way towards ballasting - she sits very low in the water. Jotika advised 60mm 4 bladed props, which were duly fitted. As I have already said, I use a Taranis radio and this has the advantage of being able to set up a differential drive between the motors and rudder in the transmitter. As you can see on the video, she turns in her own length. You will also see from the video the 'deck cargo', or cardboard box full of the white metal fittings. This gave me a better idea of how much more ballast I would require for the finished model. I did have a scary moment when the 'deck cargo' shifted and she took on an alarming list to port! I thought I would be a contender for the 'Titanic Award', presented annually by our club for the best sinking. However, with nerves of steel, I navigated her safely back to the slipway. I was most pleased with the way she handled and moved through the water. The motors and props supply more than enough power and she will require very little more ballasting.

5 years ago by cormorant

Blog

New drive Train and Oiler

Most of this actually took place last August / July! Regular readers may have seen that when Dad built this boat in the 60s he put a Taycol Target field motor in it. About 25 years ago I put a Decaperm and 'modern' transistor ESC in her to provide forward and reverse. Performance was sedate to say the least. I have since modified the Taycol (see below) so it can be run forward and reverse and decided to put it in an ancient Billings Boats Danish fish cutter (Gina) that I inherited from an Aunt. The cutter is badly in need of renovation (see pic 1) and the Taycol will be more suited to her performance requirement! On advice from Canabus in Hobart I obtained a Propdrive 2830 1000kV brushless motor, appropriate ESC and a 35mm 3 blade prop from Raboesch. Pic 2 shows the old and new motors. Next step was to trial fit new motor mount, coupling and prop. Pics 3 &4. While doing this it became obvious that a new shaft was in order, as mentioned in last update. Soooo, - appropriate stainless steel rod, thrust washers and set ring were acquired and back to the workshop. After cutting to length to accommodate the new coupling type a 3mm thread was cut a the prop end. At the inboard end I milled recesses for the grub screws in the set ring and the coupling, pics 5 - 7. I don't like to just file(or even mill) flats for the screws cos they have a tendency to slip and work loose😡 Trial fitted the new shaft and found I'd boobed a bit with the measurements and need extra thrust washers to make up the difference. 😲 Pic 8. No sweat, they came in a pack of 50 anyway😊 You can also see in this pic that I decided to fit an oiler pipe while everything was in bits anyway.😉 To solder it on in a cramped space without setting the boat on fire 😡 I packed a wet rag underneath and used a gas Kitchen Torch! Known as a 'Gas Gourmet Burner'. Yep, those handy little gas torches like your Missus uses to melt the brown sugar on her Crème Brûlée!! So do I, delicious 😜😉 The torches are not expensive, small, very handy, refillable with lighter gas and can be adjusted to a very small hot flame. ideal for this job. See pics 9 & 10. Pic 11 shows the new motor & mount, shaft and coupling all trial fitted after using a brass alignment tool I quickly made up on the lathe. Pic also shows the trial electrical installation after cleaning up the 'machinery compartment' a little and painting with silver Hammerite. A Quickrun BL ESC is sitting in the bottom in one of the trays my Dad originally fitted for the 2 wet cell (very wet!) 6V batteries. The home made board on the left carries the battery and ESC connectors, main ON/OFF switch with LED, blade fuse holder with a 20A fuse and a green LED which tells me if the fuse is blown! Stuck on the walls (OK Bulkheads!) with so called Servo Tape are a 6 ch Turnigy iA6 2.4Gig RX and the arming switch for the ESC. Battery compartment is sized to fit 2S and 3S hard case LiPos. For trials I can fit my Wattmeter forward of the switchboard and splice it into the battery supply using Tamiya connectors. Might change these to XT60s later if current drain is more than 12 to 15A. All for now, all this was pulled out again preparatory to cosmetics on the hull, decks, cabin roof and walls inside and out. But that's another chapter so, 'Tune in next week, same time same channel when once again it's time for 'WHAT DO YOU MEAN BUCK RODGERS IS APPROACHING!? 😁 Or 'The Saga of the Cabin Roof' 😉 Cheers Doug 😎 BTW: After drilling the shaft tube for the oiler pipe I flushed it out with light machine oil (pumped in from a big syringe) and shoved a few pipe cleaners through (rotating them on the way) to remove any remaining drill swarf!!

6 years ago by RNinMunich

Wiki

Battery Charging

NOT from me (RNinMunich)! I just edited it to delete a previous comment of mine! batteries should not be discharged and kept charged up as much as possible. Discharging these batteries will reduce their capacity. if they are kept for any length of time without a charge, they will not charge up again. To charge up these batteries use the same formula. However batteries can cope with heavy currents and it is sometimes a good idea to charge them up with a higher current. Now and then charge them up with double the current as usual and for half the time. So for example, a 5000mA/h battery, should be charged on 1 Amp for 5 hours. Winter Storage To ensure they will be fine when next used make sure they have a top-up charge every couple of weeks. Half the length of time of a normal charge. DO NOT HAVE THE BATTERY ON A CONSTANT TRICKLE CHARGE! Large 12 v batteries (e.g. old home security batteries) have a time constant of approx 4 hrs so need to be charged 5 x 4 hrs = 20 hrs. I leave mine on overnight which usually does the job, offload charged battery volts are approx 13.8 v.

5 years ago by Tall Paul

Wiki

Battery Charging

NOT from me (RNinMunich)! I just edited it to delete a previous comment of mine! batteries should not be discharged and kept charged up as much as possible. Discharging these batteries will reduce their capacity. if they are kept for any length of time without a charge, they will not charge up again. To charge up these batteries use the same formula. However batteries can cope with heavy currents and it is sometimes a good idea to charge them up with a higher current. Now and then charge them up with double the current as usual and for half the time. So for example, a 5000mA/h battery, should be charged on 1 Amp for 5 hours. Winter Storage To ensure they will be fine when next used make sure they have a top-up charge every couple of weeks. Half the length of time of a normal charge. DO NOT HAVE THE BATTERY ON A CONSTANT TRICKLE CHARGE! Large 12 v batteries (e.g. old home security batteries) have a time constant of approx 4 hrs so need to be charged 5 x 4 hrs = 20 hrs. I leave mine on overnight which usually does the job, offload battery volts are approx 13.8 v.

5 years ago by RNinMunich

Wiki

Battery Charging

DRAFT: TO BE REVISED AND UPDATED SHORTLY!! (RN) batteries should not be discharged and kept charged up as much as possible. Discharging these batteries will reduce their capacity. if they are kept for any length of time without a charge, they will not charge up again. To charge up these batteries use the same formula. However batteries can cope with heavy currents and it is sometimes a good idea to charge them up with a higher current. Now and then charge them up with double the current as usual and for half the time. So for example, a 5000mA/h battery, should be charged on 1 Amp for 5 hours. Winter Storage To ensure they will be fine when next used make sure they have a top-up charge every couple of weeks. Half the length of time of a normal charge. DO NOT HAVE THE BATTERY ON A CONSTANT TRICKLE CHARGE! Large 12 v batteries (e.g. old home security batteries) have a time constant of approx 4 hrs so need to be charged 5 x 4 hrs = 20 hrs. I leave mine on overnight which usually does the job, offload battery volts are approx 13.8 v.

5 years ago by Tall Paul

Forum

Anteo 2 Tug

You can power a brushless from batteries electric is electric. Lipo batteries are often used because of their ability to provide power with a relatively low weight and can dump LOTS of amps. As Colin pointed out 2 6volt batteries in parallel will provide 6 volts and cannot be tapped for 12v to obtain 12v the batteries need to be in series and 6 volts can be tapped off but will only provide the energy from one of the two batteries.

5 years ago by Haverlock

Forum

Anteo 2 Tug

Hi Havelock, this is my first boat build,been doing rc model aircraft for 60 years,I know all there is about brushless motors and lipos.The kit specified batteries and I am using a 2_1 mfa motor and gearbox not quite sure what esc I have got. Lot of this was guesswork.The batteries will complement whatever ballast I need.2x6v in parallel and I can tap of 12 v for lights smoke etc I think.

5 years ago by Dick

Forum

Fairmile D 1/24 Scale Build

Don't quite understand why you would want to run four props & motors. One of my fleet is a old Precident Perkasa, in all wood including the hull. Powered by a 12v 7ah battery a single 550 motor and a three blade prop. As you can probably imagine she is heavy but still gets on the plane to mimic the real thing, will admit the motor did get a bit hot untill I fitted a heat sink with fan cooling. I also have a Hooben Perkasa in injection moulded plastic, yet to be built but intend to use the same set up. Cheers for now John👍

5 years ago by bikerjohn57

Forum

Ship rudders

Couple of other plates. When I have finished the rudder and housed it to the rudder post and sorted the rc control linkage for it I will take out too the pond for ballasting and a swim. Once I know how much and where ballasting is needed I shall insert aluminium angle in to the hull to house batteries and lead blocks.

5 years ago by Toby

Forum

A return to the hobby!

I would appreciate some input as to the type of battery. My inclination is to go for a lead-acid, as I would like the additional weight. I feel that most models look too light on the water. The motor is a mtroniks 660 with a Viper Marine 25A ESC. Any advice would be appreciated!

6 years ago by J Barry

Blog

Vintage Model Works 46'' RAF Crash Tender

Here's the history bit so pay attention... Many years ago as a boy in the fifth year of my north London secondary school, circa 1971, our woodwork class was given the option to make something of our own choice. Having mastered the majority of joints, wood turning, finishing techniques and the making of table lamps, stools and bookshelves etc. this seemed a good idea, so myself and a fellow classmate and model making chum asked if we could construct a model boat. The teacher, on hearing that it was to be from a kit and not from scratch was a little surprised but agreed. So my friend and I jointly invested about 20 quid in an Aerokits 34.5 inch RAF Crash Tender from Blunts' model shop in Mill Hill (long since gone like many others) and we set about construction during lesson time and sometimes at break times. I recall we used "Cascamite" to glue it all together on the advice of the woodwork teacher because neither 'Scotch' glue nor PVA was suited to marine construction. Good progress was made over the course of our last year at school but it was never fully completed, only requiring painting, running gear and detailing. My friend decided that he needed to withdraw from the project as he was enrolling in a college away from home to study for a career in the merchant navy and I agreed to buy out his share and continue with the project. And so it was that I carried on with the painting and installing the running gear which consisted of a 1.5 cc marine diesel engine, water pickup, prop shaft and rudder and a MacGregor radio system with a stick for steering and a single button for speed control. The engine and radio came from Michael's Models in Finchley (also long gone) for £20 as my elder brother, who had started a Saturday job there, was able to get a staff discount for me. The diesel engine was noisy and smelly and a pig to start with a leather thong around the flywheel and I decided to abandon this means of propulsion (I foolishly ran it for slightly too long 'dry' and melted the soldering around the brass water jacket!). By now I had graduated from my part time job in Woolies to an engineering apprentice with Post Office Telephones and my new income of 20 quid per week could support my modelling and electronics hobbies after my contribution to the household for my keep. So off to the model shop to buy a Taycol Supermarine electric motor, two 12v volt batteries and a suitable charger. The diesel came out and was sold on Exchange & Mart and the mount and coupling re-made to accommodate the new Taycol motor. What an improvement that was! I can't remember now what speed controller or servo I used but whatever it was did the job, and it went like the clappers on Friary Park boating lake (also long since gone) even though the radio control system was a bit crude with the non-proportional steering and 'blip' throttle control. The boating took a back seat when I acquired my driving licence and my first car (a rusty old Cortina Mk 1) and I also got involved in sound recording for radio. I decided to sell the boat and bits for £60 through Exchange & Mart and bought an Akai 4000DS tape recorder and a 'Chilton' audio mixer, built a home studio and along with a good mate of mine started making radio commercials for the new commercial radio stations including London's Capital Radio. We even won a 'Campaign' advertising award for one of our efforts! And so after several years as a 'phone engineer I moved into professional recording for A/V and broadcast and then into TV production. Fast forward to today. Semi-retired with grand kids and with more free time on my hands I still had an interest in model making so in Jan 2016 went to the Model Engineer exhibition at nearby 'Ally Pally'. It was there that I saw an RAF crash tender just like the one I built all those years ago and got into conversation with the chap on the stand. This re-ignited my model making interests and I researched the hobby and that model in particular.

8 years ago by robbob

Forum

Tarpon hardware help

Thanks Steve, my choice would have been , but the boat is to be a present for my son. He works abroad for long periods and I recon a would go flat beyond recovery. So my choice now is a NiMh Pack SubC of 9.8 or12V, minimum 5000mah in case he blows hiself up using LiPo's. I want the boat to have a speed around a brisk walking pace. Thank you again for your reply.

6 years ago by Gordon-B

Forum

Tarpon hardware help

Pretty boat that. Probably know as much about motors as you do but, What may make a difference is what battery you intend to use, Style of boat does not make for rushing about the pond so a 12v battery would probably be in order in which case the 12v nominal motor would suit. if you plan to use Nicad 7.2v battery then the other motor is more suited. waits to be shot down or should that be scuttled. Steve

6 years ago by steve-d

Forum

54'' long Cervia tug.

My Cervia was ready built. I have replaced the Electric motor with a large servo motor (Brushed) .Direct drive and being heavy helps with ballasting. gel cells are power source. Motor rated voltage24 v but run it on 12v . low rev high torque no load current 1 amp. Shaft diameter 0.5 in. Gives some idea of power out. Being servo motor (ex computer drive 30 years old) well balanced no vibration. Photo near shore shows power of motor.

6 years ago by tysonyoung

Blog

Dumas 1203 Coast Guard Lifeboat (RNLI Waveney conversion)

So here we go again! I have decided to give other projects a rest for a time in favour of this little gem. Pick up off eBay for less than £100 NIB posted, couldnt resist! Its the Dumas (kit no:1203) 44' Coast Guard Lifeboat. I dont know if this kit is still produced by Dumas and having looked at the Die cutting of the parts, certainly seems like an old kit? However, I love my building and the challenges, so I am sure it will turn out nice at the end. Finished length 33". I shall be converting this to a RNLI Waveney Class Lifeboat and will possibly go with 44-003 named "Khami" which was based in Great Yarmouth and Gorleston, which is local to me here in Suffolk. Sadly very little turns up on this boat via Google, but at some stage may pop out to the Great Yarmouth Lifeboat station and see if I can hunt anymore info on her. I shall not be using the recommended Dumas running gear for 2 reasons, 1st its a geared set-up (I am going with MFA540 brushed direct drive) and the cost of over £150! Photos show the box artwork, plans and the included wood. Last photo shows my electrics less propshafts and props that are on order. Note the Star Wars 3.75" figures that with poetic licence could be painted to represent crew. However, at this point the model is approx 1;16 scale and the figures would be 1:18 scale so maybe too small. There are 1:16 scale lifeboat figures available but pricey? My one issue at this point is going to battery choice? do I go with a small 6v or perhaps 2 Tamiya type 7.2v NIMH in series. anyone who has built anything like this may want to advise. LIPO not an option as the Mtroniks ESC do not support LIPO. Space inside the hull may also be an issue? Another issue is going to be fabricating some propshaft struts for the rear next to the props. There is quite a bit of prop shaft exposed outside the hull, so these would be integral to support and strength of the propshafts. is there anything available off the shelf (they are included in the running gear set, but dont seem to be available on there own) of do I need to fabricate from brass tube and sheet/strip brass?

6 years ago by Skydive130

Forum

Graupner Jumbo 540 motors

I think it would be worth the risk of running the DC Motors at 7.2v (NiMh) or second choise 7.4v (Lipo) and get rid of the 6v battery. The chance of damaging the motor is limited, the battery packs will be lighter than an equivalent , but will need to by a charger as well. Always put a fuse in line rated 5 amps below that of the ESC. Or buy two higher voltage motor? only £6.99 each plus P&P link copy and paste into browser address:- https://howesmodels.co.uk/product/graupner-speed-600-8-4v-motor/

6 years ago by CB90

Response

Range Safety Launch?

Some Pictures for reference a RAF 43ft Range Safety Launch pennant '1640' and '1651' were built by 'Thornycroft' at Hampton in 1955. The Model Looks good, adding some detail and fittings will make it look great, bear in mind its a heavy boat, so you may wish to think about brushless motors and Lipo batteries, they will be a lot lighter and smaller than the 800 brushed, and batteries but you need to get advice before going down that road.

6 years ago by CB90

Forum

Which battery?

Thank you for that, it has helped a lot. I have liPo in another fast boat and do worry about the safety, I keep and charge it in a fire proof bag. I will need weight at the front of the boat so will probably assist. The build is good fun. Thanks again

6 years ago by Brianaro

Forum

Which battery?

I have a 1:16 Taymar lifeboat with twin Graupner 600 motors. Which batteries, or NiMH. Can anyone help please, what is the benefit of one over the other?

6 years ago by Brianaro

Forum

Which battery?

I tend to use LiPo's but they can be temperamental and need the correct charger. They are smaller and lighter than NiMH and give you a much greater output. NiMH are similar in size to LiPo but are heavier and will not have the same sort of power available. are the easiest to use in terms of charging but are much heavier and larger then the other 2 types but tend to be cheaper. are a good option if you need the ballast or are not limited on physical size. Cost is also a consideration a good quality charger can be an hefty investment but will serve you well and if you buy the correct type will charge/discharge any battery type that you have. I have heard horror stories about LiPo's bursting into flames, which my son did with his RC car. this was down to him not understanding this type of battery. I have not had good results in terms of endurance with NiMh but Lipo's if correctly selected will last much longer, a word of warning here though, they will stop working suddenly with no indication like running slow etc so if using LiPo's you will, need an alarm on each battery. is much easier to in terms of Voltage either 6 or 12v with real problems when connecting them in series or parallel for use or charging, a little harder with the other two types but not impossible. This has probably confused you even more but I am sure you will come the correct battery. I have to confess I have an interest in this build as I intend it to be my next project👍

6 years ago by marlina2

Forum

Which motor

Could someone advise on which motor to use in a smit amsterdam tug of approx 40 ins long with a 4 blade 3 ins dia. Prop and 4 mm. shaft, I want to run on 12v sealed battery. I am not going to tow anything but would still like a bit of power. Cheers. Neil.

6 years ago by Helineil

Forum

Longer run time

Your question does not have simple answers have you used a watt meter to see the current your motor is drawing at full throttle? With any installation its a good idea to do that test since its a good way to match motor and prop. LiPo batteries have a better current delivery than BUT you do need to be careful about end voltages so as not to damage the battery. Many ESC have a voltage cut off built in to protect LiPo batteries it may be your hitting that limit with your battery. The simplest solution to your problem is to look at the Amp/hour rating of your existing battery and get something with a higher rating. Going LiPo can give a much higher rating with a LOT less weight. The downside being the need for a special charger and the need to be careful about storage and end point voltages. As to putting 2 batteries in series to get a higher voltage yes you can BUT increasing the voltage to a brushless motor requires you match the prop to the new voltage running on the existing prop will probably cook the motor. How hot is your brushless running now? Outrunners generally can swing a bigger prop than inrunners.

6 years ago by Haverlock

Forum

Longer run time

I am using 1 12v battery in my sea queen with a brushless motor. It’s only giving me about 15 minutes on the water. The boat will get up and go for a few minutes but after that I can have the throttle wide open but the speed has gone. Can I link more than 1 battery together to give me a greater voltage which I believe a brushless motor can cope with. If so which batteries should I use and should I wire in series or parallel? I await your thoughts Thanks

6 years ago by randhbarker

Forum

Longer run time

Hi, doesn't like delivering the high currents brushless motors want. They are more suited to long term low currents. Go for a LiPo, 3 or 4S, something 7AH plus should keep you going for a while. Don't put batteries in parallel as one will inevitably try to charge the other, unless you have a hi power diode board in between them to prevent that. Cheers, Doug 😎

6 years ago by RNinMunich

Forum

Charging NiMhs, one for Doug?...

Right, gentlemen who know fings, here are shots of the wires I have. OK, I must have put the banana plugged wires in a box marked R/C Gear, I'm assuming, but the charger's wires mainly have brick red flat contact -containing plugs. However, none of my battery packs have those, they have the white things with two small round pins in 'em, one socket square, one round. The newest pack for binding duties has a little black jobby that fits the Rxs. Pictures included of all relevance. I tried to charge an old(ish) after making up a lead, but the charger put up a "Connection Break" legend on its screen. I assume that means, That one's f****d, mate. Fair enough, I thought it might be. But i still haven't worked out a lead to charge those green wrapped old NiMhs. I HAVE charged them before, because I have had two attempts at flying the aircraft. it went round in circles and then took a slate off my daughter's roof, proving that aircraft models really DO need insurance! Anyway, enclosed are three pics. The shot of a Lipo is to show that I do have such things, but that dates way back and although not damaged or bulged hasn't been charged while I've had it. it was sent to me with 2 small outrunner brushless jobbies and a couple of brushed ESCs as a thankyou for sending plywood to a part of Britain that the PO won't go to with biggish parcels. Finally....I have today received my FlySky RC set and guess what? it all works, perfectly, out of the box. it's PRE-BOUND! Whoopee do! it musdt be an upgrade as it came with a small Li-Po battery pack for the Tx. and a charge lead from USB to Tx. body. That's all great, but how do I know how long to charge it for? it currently has what looks like a full charge on it, judging by the brightness of the LEDs. Getting used to a passable impression of my son's old Subaru front wheel and tyre (complete with vented disc and caliper behind!) will take a while. I am guessing that pushing the throttle trigger forward is like a brake on a car. I assume on a boat it would be reverse? The instructions are not in any way exhaustive! But hey...on a tatty old Futaba servo it all worked a treat. Here's the pics of wires. Cheers, Martin

6 years ago by Westquay

Response

54 year old Crash Tender

Hi Boaty, right on MOST counts👍 But some of us have 'The knowledge' 😉 Check out my 'Sea Scout Jessica - Renovation' build Blog. There's a section in it where I renovate the Taycol Target Dad put in the Sea Scout in the early sixties, with two wet cell lead-acid accumulators! I also converted it to run forwards and backwards with a normal brushed ESC. How is described in the Blog. A few pics attached, from dismantled to reassembled with new brushes. Pic 3 it the test set up with Servo tester to simulate RX, standard Graupner brushed ESC and my conversion board connected between ESC and motor. Then two pics of the input waveform to the motor; forward and then reverse. Last pic shows the 'unconverted' waveform, complete with whopping great sparks 😲 I've now upgraded the Sea Scout with a brushless and the Taycol will go into a Danish Fish Cutter I am currently renovating and converting from static to RC. The Taycol's sedate performance will be more suited to the cutter which only plodded along a 8 knots or so 😉 Complete process is described in the Blog. Otherwise you are right, with few exceptions the current young 'boaters' mostly belong to the 'instant fun chuck it when it stops working throw away' generation 🤔 Cheers, Doug 😎 Martin; for yonks I did my warships in RAF light camouflage grey which mysteriously used to turn up in Dad's office in the Electronics Bay, of which Dad was the CO. 😉 A bright yellow for my scooter also appeared one time!

6 years ago by RNinMunich

Response

H.M.S. BRAVE BORDERER

If its of any help I run a all wood Perkasa with one motor (came from a old battery power tool) powered with a 12 volt, so as you can imagine its heavy. But she will plane as per any photo you can find on the NET. 😊 You state that you are waiting for parts from HK, is your BB a Hooben model ?. I purchased one of these and found the moulding of the transom to be atrocious and the company's customer service to be non existent.

6 years ago by bikerjohn57

Response

17-28 Torbay Severn Lifeboat

Hi Pugwash1 Thanks for your comments. I am no expert in motors but I think its a given that brushless motors out perform brushed motors and lipo batteries out perform and nimh batteries. Therefore if you want a model that can pick its skirts up ang go you put brushless motors with lipo batteries. If your model is not meant to rip around the pond then I dont know how to look at the pros and cons of brushed versus brushless or the merits of the different battery types. Les

6 years ago by lesfac

Response

Superstructure

Hi Doug, just big batteries in this boat, I only use li po's in my fast electric boats. Two of our club members have had fires with these so I am very careful with them. Cheers Alan

6 years ago by AlanP

Response

Amsterdam

Hi Jarvo and all guys , Thanks for all your response i have a 12 v Graupner 700 bb turbo and 2 12 v battery and a 70 mm brass prop 4 blade

6 years ago by jugge

Directory

(Tug Boat) Amsterdam

Very strong tug , can tow 2 persons in a rowboat . Runs very long time with 2 12 v 7 amp (Motor: graupner) (ESC: Artesania Latina) (8/10)

6 years ago by jugge

Forum

Huntsman 31 motor &prop advice please

Hi - I've got one of those and once I've progressed with some of my other builds I'm planning on replacing the old MFA 850 with a brushless. Being quite a heavy beast and wanting decent speed but not manic I'm looking at one of the Overlander 50 dia. brushless outrunners which will provide the torque required and use a 45 or 50mm 3 blade prop. Definitely LiPos for me. The 7.3v was fine in the boat weightwise on the water but too heavy and unwieldy for moving around and launching and with LiPos you can easily up the volts without much increase in weight. Chris

6 years ago by ChrisF

Forum

46'' Firefloat What Motor/Battery

Hi John, you might now be scratching your head, and wishing you have not asked the original question! This seems to be a common issue, as the boating community is light years behind the other disciplines, rc cars, planes helis and so on, its probably due to the facts general boating doesnt really need the later generation technology, the average boater age is probably higher than the other disciplines so budgeting might be an issue, and there is less younger blood in the clubs to explain the lipo/brushless etc. We see posts with a load of numbers, specs, warnings etc, its enough to put people off. Im a big fan of brushless/lipo/ 2.4 etc, been doing it for years, its cheaper and more efficient (once you have the basics) but for the average guy, who just wants to spend an easy afternoon at the local lake gently cruising around, brushed motors, nimhs batteries, even , will do the job👍 Your 4 foot ply boat, once painted, with fittings, will be heavy, I know, I own one. Those 600 motors are not big enough, they are better suited to the smaller 3 foot boat, then, pushing them with a 6v , just cant do it. The battery will be screaming HELP!! I started 15 years back exactly the same, 600 motor, 6v battery, massive 50mm prop, I knew no better and took advise from people who didnt know what they were talking about😡, remember those gold hi tech speed controllers!! I had one, it melted, literally melted on the first use😭 Get 700 size motors, they will need to be water cooled, as mentioned by jarvo, the nominal voltage or below isnt good enough, power them at the max voltage. Brushed means you can use one apropriate esc, look out for electronize (are they still in existance?) or mtroniks, preferably use nimhs batteries over with a high mah. If after all this you want to venture into lipos and brushless motors, go to a club, spot a boat that is similar in size to yours, if you like the performance talk to the owner and gain experience and knowledge that way, it will save money, lost time and a lot of disappointment, I have been there so feel your pain. I say I would never go back to brushed motors and none lipo batteries, but I always want silly speed, not runtime, after 15 minutes Ive had enough and am bored. Rambling over! My 4 foot boat is twin brushless and uses 4 lipo 5000mah cells per motor, it will do 25mph for 15 mins, then I go home😁 Message is, you can get a "reasonable" performance from brushed motors, with the correct batteries, right props, but weight is the enemy. Looks lie you are at Biddulph, get onto Dave M a moderator on here, and arrange to go over to see the crewe and district boys on one of their sailing days, take your boat with you, they will help👍

6 years ago by pmdevlin

Forum

46'' Firefloat What Motor/Battery

Hello chaps. I'm very new to this but have just finished scratch building a 46" Vosper Firefloat in the old Aerokits fashion (ie all wood) to the point where I've primered it, fitted a radio and couple of motors (Graupner 600 chosen at random cos they looked adequate!) and a 6v 12Ahr battery. Tried it on the local canal today and two problems. 1: its underpowered...nearly gets on the plane with a fresh battery but not quite. 2: The battery only lasts about five minutes. I'm an old git and don't understand "Lipids" or the benefits of "Brushless Motors" etc and would appreciate any help or advice any of you experienced guys could offer me please on motor/battery choices to get the thing planing and running for more than five minutes. Many thanks in anticipation Cheers John

7 years ago by moormedic

Forum

what shall we make with this!

so following a plea for a cast off boat for a friend, Dave generously donated this hull, its very nice. We discussed a gun boat, in a stand off sort of scale, as he likes military, with perhaps a superstructure that can be removed, and a different one made to fit, so two boats In one. But the more I look at it, the more I think it would make a minesweeper etc sort of thing. I'm not that well up with this sort of craft, its 43 inches long, so quite narrow, It has to be pretty much "none fussy" as the owner and builder is relatively new to this, Ill help, but its his boat, and he has clumsy hands, 😊 so it wont be super detailed. Easy to use, so single screw, more than likely brushed motor running nimhs or even (ouch🤓 that goes against everything I do!)_ Ideas please!

6 years ago by pmdevlin

Forum

Motor problem

further to my previous post, I have now fitted the two NiMH Batteries (not nicad as I kept saying)in the rear compartment, held in with Velcro, and tidied the wires up and fitted an inline fuse, yet to be wired, the boat is much lighter, however all the other Velcro is still in place so I can move them forward if needed and fit the lead or battery, so one visit to a pond and hopefully I can get it sailing correctly, my problem is I would not know what is correct and what is not, at least I have Pauls video as a reference.

7 years ago by RichardSReade

Forum

Motor problem

very interesting Paul, I watched the video, I have weighed the boat as best I can, using the kitchen scales, the boat without any batteries or lead is 6Ib 3 oz (2815 gms)the lead ballast is 2 Lb (915 gms)the battery is 5Ib 9oz (grams) and the two NiMH batteries are 1Ib 10oz (747 gms) the boat now has an 850 motor with a 55mm 3 bladed prop, I do not have the experience to know whether the boat is sitting correctly without the ballast but do know that if I have the 12volt battery fitted in the only place it will fit then I need the ballast in the forward compartment making the boat weigh 13 Ib (6252 gms). if you are saying that I should keep it light then I could move theNiMH batteries to the compartment rear of the motor thus moving the weight towards the back and ditch the LA battery and lead ballast, I have no idea which part of the country you reside in, is it too far for me to drive to? as your sailing pond looks a lot better than the postage stamp we have to use in Swindon.

7 years ago by RichardSReade

Forum

Motor problem

Hi Richard, that is way too big and heavy. I Remember going on hols as a kid, car was loaded up, all family, roofrack, deck chairs, tent and so on, and Dads old Moggie Traveller would barely climb the Welsh hills! Same here, its just dead weight, ideal for a tug etc, no speed required, and ballast needed. This boat wasn't any slouch in its day, As Havelock says, it was originally built as a ic powered model so could stand being heavy. To achieve balance, its a matter of moving things around, not adding, so just move things forward, you will be surprised how the weight increases once you start adding Deck clutter, fittings and so on. Lightweight, is good. Your comment, stood up in the water at half throttle isn't going fast, its just bad weight displacement causing the bow tyo be too high. That setup would never have been that fast, the motor/battery combo will never cause a heavy ply boat to be going that fast its standing on end Couple of things to consider. Your nimhs, how many times have these been cycled, and what sort of charger are you using? A reasonable charger will give the information, if I know what you are using, Ill advise accordingly as you might not be getting the best from these batteries what prop are you on Think of an rc plane (if you fly them its easier) if the cog is too far back, the nose is pitching up, and its almost impossible to control, it almost porpoises in the air, and is very bad. COG is vital on a rc plane, nose heavy is better, only because its more controllable. COG is equally important with a boat, but harder to see the implications, the hull will give us false info, such as if the bow is up its on the plane, no, not necessarily, its not planing due to speed, its just out of balance. Shifting the weight radically will let you see this, sorry for the ramble, Wish you where closer to me I would love to help hands on👍 Ive tried to find a suitable video of my Huntman to display what I'm rambling on about. This video is poor quality, but it displays that boat moving very fast (25mph with on board data logger) but look how flat it is, its planning, as the forward 1/3 of the hull is out of the water, but its not standing on its tail, this is because its balanced. You boat is pretty similar in design to this so whilst you wont want to go this fast, the picture should look the same. This Huntsman weighs 6kg with batteries (lipos, you will NEVER get a nimh or to do this) and is 4 foot long, so quite a heavy old girl first constructed as an IC model in the early 70's. https://www.youtube.com/watch?v=e5-YmmElIfk&t=34s and here is a picture of my 3 foot aerokits fireboat, bow up, is it planing, no, its way out of balance, it wasnt actaully going that fast Hope that helps Paul

7 years ago by pmdevlin

Forum

Motor problem

the first time I sailed the boat with the old motor she was fast and literally stood up in the water on half throttle with just the battery and no ballast, it was sitting with the back end about half an inch above the underside skins and the bow was well out of the water, I was advised by one of the club members that I needed to trim the boat so it was down at the front but keeping the stern approximately where it was, therfore the lead in the compartment forward of the motor and the battery in the compartment behind. However the 5000mAh and the 3300mAh batteries are not connect and are only held in place with a bit of velcro, also the lead in the front is just shaped to the hull and cannot move, but I can lift it out, so I will see how it runs next week

7 years ago by RichardSReade

Forum

Motor problem

using a is ok BUT a LIPO can deliver more current. See how things go and consider a LIPO in the future to increase performance.

7 years ago by Haverlock

Forum

Motor problem

Motor fitted to platform and luckily there was enough depth to screw the motor platform to the stringers, I have moved the reciever forward to where it was and resecured the powerbox in a better position, just the leads with the bullet connectors from the motor to fit, although I have fitted the sealed 12 volt battery instead of the lead ballast (same weight) I have left the7.2v in situ as I trimmed the boat with them in and will see how it goes, it may have too much power on 12 volt and at least if my finger on the stick lacks control on the speed, I can slow things down by swapping over to the 7.2v batteries. If and when the sailing side is sorted, after seeing the pictures of members boats and ships, I think I will give it a good rub down and respray and smarten the inside up as well. Eventually I will get on with the Lloydsman

7 years ago by RichardSReade

Forum

Motor problem

I looked at the Cornwall model site and saw that, what i have decided to do is to leave the two Ni cad batteries in situ and I have weighed the rear/mid section lead weight and it is just 56 grams heavier than the 12 volt 7 amp/h alarm battery so I will use the 12 volt battery and ditch the lead, the weight of the boat will be the same, I also trimmed the lead at the front end so the bow will come up a fraction more. I have taken the prop of and measured it to be a 55mm, so I am going to fit the water intake, hopefully with some advice from the forum "techys"as to the position, in the photos this is where I can fit it so it is out of the way of the rudder and prop.what do you reckon, I can then get a suitable motor with a water jacket which will be happy to run on 12 volt with enough power not to get hot turning a 45 to 50 mm two blade "x" prop, as suggested by pmdevlin, I may get the Lloydsman up and running as all that needs is dusting of and batteries charging up, (two 12 volt 7amp/h in parallel) and the receiver from the commander fitted although I have not floated it I bought it as a complete working model in 2015, so it is about time it came out of dry dock, also I can look to repairing the rigging and finishing the Odessy Yacht I bought at the same time as the Llyodsman also in dry dock.

7 years ago by RichardSReade

Forum

Motor problem

Thank you gents, I will get a bigger motor and reduce the prop size as I do not want it any faster than it is, also a smaller prop as everyone has said will reduce the power drained from the battery, I have a water scoop and tubing so will be fitting that today and will fit a water jacket around the motor, also I am thinking weighing the lead weight fitted in the compartment behind the motor and replace some or all of it and fit a 12 volt 7 amph sealed battery, presumably this will last longer than the present batteries fitted, or will it?

7 years ago by RichardSReade

Response

Sea Queen

Hi Ned, Welcome aboard 👍 On my Sea Scout (little brother of the Sea Queen) I used silicon sealant (a la bathroom!) and a small brass screw in each corner. it had to be good cos I had the RX, RX battery and rudder servo tucked in there! My boat was also started by Dad in the sixties. He had it free running with a Taycol Target and wet (very!) 6V cells. I upgraded to RC and Decaperm motor about 25 years ago and am currently restoring and converting to brushless 😲 Happy boating, Cheers Doug 😎

7 years ago by RNinMunich

Forum

General sailing

Hi Baggie, What type are they? NiCad, NiMh or LiPo? If they are LiPos and they are getting very hot disconnect them IMMEDIATELY and take them to a recycling centre! If they are Nixx and getting hot (warm is allowed) reduce the charge current to the minimum! Take account of the 'Fast charge rate (Amps) specified by the manufacturer. Personally I would not use 3.5 or 5 Amps for anything except . Note how long the battery lasts in use. if it seems to be getting shorter than it used to be then probably at least one cell has a high internal resistance and it's days are numbered. it will only get worse. Use an appropriate charger for each type, and that 'knows' when to stop charging! Most modern units can be switched to appropriate programmes. Cheers Doug 😎

7 years ago by RNinMunich

Forum

Dauntless

Hi Doug...it's this one: and no that little issue is still ongoing...have changed my Tx/Rx/ESC to Turnigy....the Mtroniks ESC's I was using were 'compromised' regarding the set-up...I now have a programmable card to set up my ESC's - The Dauntless has been converted to a Police launch, it's a twin screw using two Electronize ESC's.....just needs a Tx/Rx and batteries, possibly looking at x2

7 years ago by NickW

Forum

battery charging

Hi Doug I use a charger that measures the internal resistance of my batteries. Damaged cells exhibit high internal resistance and cannot be recovered to their full capacity. I agree you can flash the cells and they will recover the voltage but will not take or deliver the current. As a result they will quickly discharge under load and prevent the whole pack from delivering its full capacity. I sail model boats on a large lake and recovering a model due to battery failure is difficult, so I don't risk using sub standard batteries. I have not used wet batteries for many years but I agree the Epsom salts trick did work on such batteries. I agree flashing is highly dangerous with any battery as there is a high risk of explosion. Great care should be taken and, unless you are competent, should not be attempted. Take care Dave

7 years ago by Dave M

Forum

battery charging

Good one Onetenor 👍 I've also used the 'flash' technique successfully for years, BUT ONLY ON Ni-cad, NiMh or LA. it's the basis of the battery 'rejuvenators'. in that case it shocks the sulphate off the plates. DO NOT USE THIS TECHNIQUE FOR LIPOs OR ANY LI*** TYPE ACCU. The results would be unpredictable and downright bl...y dangerous. 😡 I would not want to be in the same room 😲 Have fun but don't blow yourselves up! 😆 Cheers Doug 😎 PS Roy - there's nowt much wrong with your battery if it charges to 7V. One cell is a little weaker OK, but if it doesn't show a tendency to collapse under load the accu will be OK if you don't demand too much current from it. Dave M's accus also only charged to 6.8V, an average of 1.36V / cell! Happy sailing all😊

7 years ago by RNinMunich

Forum

BATTERY CHARGING

Hi Joe I would not have the ESC and charger attached at the same time. You could use a heavy duty double pole two way switch or just unplug the ESC and plug in the charger, best option in my opinion. Mains chargers for SLA batteries will limit the voltage and current but they are susceptible to transient surges from the mains which could produce a similar surge to the ESC if connected. You should also be aware that batteries (includuing SLAs) can in certain circumstances give off highly explosive gas and in an enclosed space any spark could result in a big bang that would not be good for the model or anyone in close proximity. If you really have to charge in the boat make sure there is plenty of air space and take care when attaching and removing the leads. This applies to the charger and the ESC leads... Take care Dave

7 years ago by Dave M

Forum

Battery problems

G/Day I have not got any idea about electronics. I have got a 47 inch Perkasa Patrol Boat running with a single Brush less Turnigy 3974-2200kv water cooled motor and a water cooled Turnigy 160A ESC running directly from a rechargeable sealed lead-acid battery RL1270(12v7.0Ah/20hr). My problem is when the motor is running at high reves it cuts out after a few minuets. Is this from low battery or wrong setup? All the help i can get to get my boat running smoothly would be much appreciated . thank you. Allan

7 years ago by Patto