Blog

Krick Police Launch

I have just started to build the Police Launch that I have had for a while. Work commitments have left me with little time lately but hopefully I can get a good run on this one for a while. I hope to finish it by late July which just leaves me enough time to send it to Hungary so that I can test it. The kit is said to be good for a beginner. This would be good as many years ago I built a Patrol Torpedo Boat which took me five years. I am currently restoring this one as well but I think that will take most of this year to complete.😁 I have started by buying the speed controller. The motor is a 400 brushed. Probably not going to be too difficult to keep up with this one. The kit itself is not too bad considering the price, but I do feel that the ABS vacuum formed hull could be of a slightly better quality. Also I am finding the ply wood to be rather brittle. Does anybody have an idea for a good filler to use to fill the chips which will take to acrylic paint. I have prepared the hull and added the shaft and rudder holes. Care taken here to avoid splits in the plastic. Cellotape on both sides before drilling helps.🤓 I have assembled the internal parts which hold the motor, battery and rudder and also fitted the prop shaft.😲 I will start on the deck and superstructure next. An additional note about the kit. The instructions are reasonable but they are in black and white which is not helpful considering they are photograph based with text. I found a PDF on the web which is in full colour. Why don`t Krick supply this. Surely not that expensive.🤔

6 years ago by MouldBuilder

Blog

Revell Gato Class Submarine Conversion.

I am about to start the most ambitious project to date. This one will be running alongside the three others currently on the go, The Police Boat which is nearly completed, The Dusseldorf Fire Boat which is well underway and the PTB upgrade. My intention is to change this Revell model into a static dive radio controlled Submarine. I am lucky that Martin555 has agreed to help whenever I get stuck which will be invaluable since he has already almost completed the same. I started by purchasing the model from Amazon for less than £50. I have also purchased the water tight tube for the electronics. I will make the end caps and sealed internal plugs from some 80mm diameter nylon I had at work. It will now come in handy that I am a toolmaker and have a considerable array of machines at my disposal. I will turn the plugs next week and find suitable o rings. I have started to prepare the hull. There is an enormous amount of work required to adjust the standard kit. A lot of cutting and drilling. I have prepared the split lines and glued in the alignment pegs. I have ordered suitable shafts and s from the USA. They should be here in a couple of weeks. Next job is to stick the two halves together and start the cutting.

5 years ago by MouldBuilder

Blog

Water Supply

Much head scratching about the plumbing🤣 I mentioned that I may consider a separate water supply for the monitors as there were so many issues with it all being sourced from the pic-up pipe, I tried with solenoid valves etc etc but there are too many issues about switching, water flow and future breakdowns in the system. So a separate water supply, however this has its own issues, firstly another hole in the hull mid-ship and a pick-up that wouldn't force water into the hoses when the boat is going forward, and being able to self prime the pump when stationary. I've come up with this design that fits on the underside of the hull (with some reinforcement) mid ship

4 years ago by mturpin013

Forum

Graupner Closing

Sad that their components will no longer be available - the geared motors sets - the outboard motors - s - shafts etc etc etc . All very useful items to say nothing of the kits they produced. Wonder how much the closure will affect the model aircraft fraternity?????????

4 years ago by redpmg

Response

Re: Forecastle Bulwarks and Hull Fittings

Thanks for the info Steve. I know what you mean about Ron Dean, have got a USS KIDD that I bought from a good friend, upon building it, I noticed a starboard grill missing, I asked Ron who was going to the show at Blackpool, to bring one, when I asked him, he said he had forgotten and to give him a call, but now will have to pay postage, what a Plonker! Cheers, Peter

5 years ago by Rookysailor

Forum

Age of steam

Kitchen rudder but on a Midwest boat you may have to use very small servos.Or you can look for a variable pitch which are expensive. I have one of those boat that I made in the late 80's. The engine was made of white metal/zinc, had to make a new one, I used the sterno to fuel but what I did was to build up steam first put the fire out reload with sterno and I got between 25 to 30 minute runs, These are great boats!

5 years ago by RonH

Response

Re: SEAPLANE TENDER TANK TEST 2

"Just a little idea using a syringe body, small motor and fan ." I can see why it's labelled "Single Use Only" Martin 😉 One trip and the coil has melted through the syringe and set fire to the boat 😭😭 Exit one VERY unhappy camper er sailor! 😎

5 years ago by RNinMunich

Response

Re: SEAPLANE TENDER TANK TEST 2

Hi Jb, Just a little idea using a syringe body, small motor and fan . Martin555.

5 years ago by Martin555

Response

Re: 40'' Seaplane Tender, new build. mods and improvements.

Hi Doug, - rats nest indeed! 😂 Thanks for the nice comment BTW, I do actually have ID tags (masking tape on wires),- you can't see most of them as they are hidden behind the felt lining and under the deck and floor boards. I also use male and female JST plugs reversed when 2 connections are close together. Main power into systems comes from each battery, and splits into a number of JST connectors which supply each particular unit. It's hard to get so many wires neat and tidy in a limited space, as they don't always exit or enter the units in a convenient direction, and some don't bend all that well. Short of cutting all the wires off and substituting my own, I just do the best to fit them as they come. Looks messy but when you are trying to fit 2 ESCs, 2 sound units,(which have to be lifted out while wired, to get at batteries) a water pump, 2 1800 mAh LiPos, 2 remote switches, a battery monitor, 2 shaft oiler reservoirs and a UBEC and associated wiring (including light feed wiring to cabin top) into a space of around 200x200x100mm it's bound to get messy! A problem is finding nice quality flexible silicone wire (especially on JST plugs) which bends nicely round things. Most wire products you get on line are stiff poor quality stuff, and you don't know what type it will be till you get it. Main thing is that it all works and you can't see it with the top on😁😊 Re- the smoke,- I have 3 Heng Long smokers (one of which I've modded (see vid) and am experimenting with ways of making them compact, (been done on You Tube with a smaller fan than I used (in place of original pump) stuck directly to the side of the smoker tank. The smokers work really well, - just have to reduce the size (maybe a small motor in a tube with a to replace the pump) Hard part is finding smoke which is 'waterproof' as it has to come out with the exhaust water. Usual baby oil smoke just disappears and doesn't travel well down tubes, (even without water) so the unit needs to be close to the exit with a non oily smoke. Perhaps an incense stick or cigarette in a tube?😀😊 JB

5 years ago by jbkiwi

Response

Re: She runs!!

Hi Doug..I’m using 3000 mah nimh 6 cell packs. I’m pulling maybe 3.5 to 4 amps under way, she tested about 4.5 at full chat while being held steady. Once under way the should unload a bit lowering my amp draw. We drover around the lake for real close to an hours running time and the packs were showing about 7.5 to 7.6 volts no load.im running a simple y harnes wires in parallel feeding the esc. I’ll look at that circuit, might be something I need. Cash

5 years ago by Cashrc

Forum

46'' RAF Crash Tender

with regard to lights, white at top of mast just use an led that fits in the mast and run the wires inside. I ditched the white metal mast, its weak, and a bit of a mess imo. Its not too difficult to make one from some cheap brass. green and red nav lights (I used the tips from pens to replicate the shapes of the mountings) blue front of wheelhouse under the mast stand (see number 72 on attachment) white search light much talk of the white stern light! but no mention in any of the Vosper paperwork, (but it is on one of the pictures) Then if you want to illuminate inside the cabins etc, I used pygmy bulbs to give the yellow look It now all depends on the level of detail you want. I made my mast to fold as per the original, I read that the unusual shape of the mast legs was due to the fact they used plane blades (RAF boat don't forget) they do resemble this, but its a nice story!

5 years ago by pmdevlin

Forum

Magnetic motors

Hi Martin, "This type of motor would be good if you could control the speed." Since the motor uses permanent magnets on both stator and rotor the speed will also be permanent and unalterable, as both magnetic fields are constant. To alter the speed of the vessel (or go astern!) you would need to alter the pitch of the prop and hence the thrust. 'Variable pitch s!' This is the operating principle of constant speed turbo-prop aero engines for example. VP props are also used on many ships these days. Needs some intricate gearing built into the prop hub, and controlled by !? 🤔 Control shaft running inside a hollow prop shaft? Don't know of any model versions on the market so if you find one, or come up with a way to DIY one I'd be MOST interested.😉 A constant speed version driving a generator might be useful though👍 IF it has enough torque. Might work with a decent gearbox? Cheers, Doug 😎

5 years ago by RNinMunich

Forum

Fishtailing

Hi DG, Reading through one of the articles I noticed the following. Always ground the motor cans by connecting them to your shaft stuffing box. If they are not connected to anything other than the suppression capacitors, they will act as big fat antennas radiating the RFI coupled into them by the capacitors! Exactly the opposite of what you want! Also ground the negative battery supply lead so that you have ONE 0V or ground reference point. Make sure the end of the stuffing box has a small area without paint to make contact with the pond water. Although the pond is not a great electrical conductor, it does act as a weak ground plane, dissipating the motor can RFI signals to ground. I am assuming that you have to connect a negative lead to the motor can and then on to the prop shaft. In all the years that I have been model making I have never done this or know of anyone who has. Maybe it is something that I should do. Martin.

5 years ago by Martin555

Forum

Martin Westquay's Piper Cub ;-)

Hi Martin, most of us played with the Keil Kraft & Veron kits in our youth. The small kits fitted the pocket money slot very well - most succumbed early - have memories of Jetex units climbing away from your new model on their own - never to be found. Others succumbed to the force of a penny Ronden "Flash Bomb" lit on launch - spectacular. Then there were the larger kits - rubber powered built with fathers assistance - home carved s - which flew out of sight - also never to be seen again. One climbed out on a thermal until a dot in the sky - turned up on a farm 20 miles away unscathed - always had name and address/phone no on a small card on the models.....Later the usual ED Bee's , Allan Mercury 1.5's etc . Watched a 40" span Piper of mine trying to take off with a friends clapped out Bee - ran the length of the rugby field and lifted just in time to intercept the posts............ Have 90% of the flying scale model plans - always mean to build one but designing and making commercial kids kits on the Laser intervenes. So far Land Rover series 1 , Defender, Suzuki SJ410 , Generic Jeep, Willys 1946 Jeep, Pitts Special , Tiger Moth and Eurocopter - all made with 3mm MDF - either fully designed or heavily modified by myself.

5 years ago by redpmg

Forum

Magnetic motors

I have been thinking with the idea of magnetic motors and trying to get away from normal s. At the moment I am unable to spend much time in my little workshop (health reason) So I have had these crazy ideas buzzing around in my head. Normal this leads to me making something different. Martin.

5 years ago by Martin555

Forum

Magnetic motors

Hi JB, Perhaps he means very little cavitation or less friction. I have been trying to look for some sort of propulsion that is not water jet or standard . As you know I like to tinker. Maybe it is something that I will have to try and design. Some years ago I seem to remember that China or Japan had a system that was so different to all other normal propulsion systems, but I cannot find it anywhere. Perhaps I dreamt it! Martin.

5 years ago by Martin555

Forum

direction.

Hi Guys, I have found this in my box of bits and was wondering what direction it should be put on the prop shaft. It is 35mm tip to tip. It has SX marked on one blade. Also has the letter L marked on it (assuming left hand) And it also has a slot on the main centre section. Unfortunately that is all I know about it. So I thought there is no better place to ask a question than on this site as the members here are extremely knowledgeable. I am not that good at photography but I think you can see what I am trying to say. Martin.

5 years ago by Martin555

Forum

direction.

Hi DG, Thank you. It goes to prove that you are never to old to learn. I thought that there was a worldwide standard. Looking at the video it reminds me that I had some friends that worked with a cavitation tunnel, and they would never talk about there work there. Obviously we all were doing MOD work at the time. However it is interesting to see the different results that different s have. Thank again. Martin.

5 years ago by Martin555

Blog

Stern Module assembly

This weekend I decided to do more work on the Gato Submarine. Now I am starting to realise how big this job to build the model is, let alone the WTC which I am thinking about and starting to plan in tandem. I have been working on the stern module today trying to get the rudder and aft planes in a working state. I have followed the video made by a kind soul on the internet which I am finding very helpful. To make them fit properly has resulted in a lot of filing and reshaping particularly on the rudder. All of the edges were interfering all over. After a considerable amount of adjusting, they now fit and work perfectly. A hole was carefully drilled right through the height of the rudder to allow for a shaft to be inserted for operation. Small holes were also drilled through some waste material to produce two running bearings for the rudder shaft. There has had to be a considerable amount of material removal inside the stern module halves to allow for the planes and rudder to work. This was done using a burr in the Dremel and files. Great care was taken not to remove too much and go right through the part. I am having a little problem with warpage of one of the stern halves. You can see the gap between the parts in one of the photographs. It might be that they will glue together without incident if I fix them well with bands during curing. Does anybody have a cunning plan to straighten this part before gluing? I have purchased the shafts and tubes so further work on this module will continue when they arrive, probably towards the end of July. I have now purchased my chosen motors. They are MFA 360. I have also ordered the raw materials to make the motor mount and servo trays. I wonder if I have to put the usual three suppressors on the motors if running a 40Mhz transmitter. Next time I am going to work on the bow planes. I will have them working and retracting. I bought the gears for the retracting mechanism today but have found them to be too big on diameter to fit two side by side in the bow module. The gears are perfect in every other way so I think I will reduce them to quadrants which should fit nicely. More cad design work for me I think.

5 years ago by MouldBuilder

Response

Re: Joining the fuselage.

As the submarine does not have to move very fast and has two motors driving 35mm s, does anybody have a suggestion on how many rpm the shafts need to go. I am sure that torque is more important than rpm but a forward speed of around walking pace should be enough. Your thoughts would be appreciated. Peter. BTW jb, the bow planes are in the kit, the actuating mechanism is the item I have to figure out.

5 years ago by MouldBuilder

Response

Re: Revell Gato Class Submarine Conversion.

Hi Bill. You have made a really nice looking model. This project will take a while but I am looking forward to it. The s, shafts and joints can be found on ebay. The item number is 273490619808. The seller is rc-sub-workshop. They are a little expensive but they do come with all of the required parts. I will let you know what they are like when they arrive. They are coming from Hong Kong I think. Peter.😊

5 years ago by MouldBuilder

Forum

Prop size and speed

Hi, If you have a left hand and a right hand then you will need to reverse one of the motors. As for s I think that at the and of the day you will have to experiment to find out what suits your needs as you must remember that you are dealing with scale models and that the water it is on is not at the same scale. A 2-blade produces two pressure pulses per revolution, whereas a 3-blade will produce three smaller pulses per revolution for the same amount of total thrust. As a result, the 3-blade prop will be inherently smoother and therefore quieter. A 4-blade can improve all those characteristics that make for practical, all-around boat performance. Four-blade props usually have a lower pitch to keep the rpms the same as a 3-blade. But are 4-Blades Slow? So, why might a 4-blade generally be slower than its 3-blade counterpart? To be honest, many 3-blade/4-blade speed comparisons are simply not fair. That’s because the respective s in question are simply different styles, designed with different purposes in mind—different diameters, rakes, cupping, and blade shapes. If however, for comparison purposes, we take two s, identical in design (blade shape, diameter, rake, cup, etc.) that are appropriate for a given application, and simply add a blade, we get a truer representation of just where the difference lies. The addition of the extra blade causes increased drag, which, in turn, requires more horsepower, in order to achieve the same rpm. Since the horsepower is limited, the rpms drop, and the speed will tend to drop with it. This is why, when going from a 3-blade to a 4-blade, the pitch is dropped an inch, or more, in order to keep rpm parity. It is this difference in pitch that causes any potential speed differentials between the 3-blade and the 4. I don't know if this will help you but this is a complex subject and you could get your self totally bogged down with all of the theory. Martin.

5 years ago by Martin555

Forum

Prop size and speed

Hi, Regarding motor speed/prop size. There are so many factors to take in to consideration on this subject. Also the fact that most model boats that you see go a lot faster than there proper scale speed. After looking at your last video I would say that you have it about right, if you were to make it go faster firstly do you have the room to fit a larger ? If not then the only course of action you have left is the motor size or blade pitch. If you change the motor you could end up with the motor rotating so fast that the will be next to useless. (If you imagine a wood screw going in to wood the distance per rotation) The pitch of the blades also determin the amount of distance per rotation that the boat will travel but that also has its limitations. This subject can get extremely complex. If your model is sitting at it's proper waterline then removing weight will not be the answer either. Without getting technical I would personally try a different pitch first then assuming I had the room try a combination of prop size and pitch. I don't know if this has helped. Martin.

5 years ago by Martin555

Forum

Hints and Tips.

Hi Guys, This little tip is mainly for the new Guys building there first twin model boats. I have heard this question many times ("what direction dose the s rotate") When you look at them from the back of the boat for forward motion the port (left) rotates anti-clockwise, and the starboard (right) rotates clockwise. Martin.

5 years ago by Martin555

Blog

WTC/Sub Driver.

Hi Guys, Just a little update on the home made WTC. Tested in Bug Blue, I had to add a little weight under the tube and held it there with elastic bands. It floated level so I submerged and surfaced it quite a few times and worked fine.(no leeks) But the battery on charge until fully charged. Unfortunately when I temporarily fitted it in my Gato and connected the universal joints to the prop shafts, then I ran both s forward and reverse slowly at first then at full rev’s, it sounded like a cement mixer full of rocks and extremely loud. So I switched it all off had a cup of Coffee then went back to it , I switched it on but nothing happened. I have had a quick look at it and the battery and fuse is ok. (I suspect the remote switch) I will have to open it up to investigate further but I am doing other things that the moment so as soon as I get the chance I will. One of the photos is the WTC on the surface the other submerged, you can see in the submerged photo the ballast party balloon full of water. Martin.

5 years ago by Martin555

Forum

Tamar Lifeboat s

Hi Want to change to brass s on Model Slipway 1/16 Tamar Lifeboat. Lost one of the original plastic supplied in kit , and looking at Roboesch 40mm brass as replacements . Not sure whether to go for 3 or 4 blades and type A or C Type props. Good speed from the supplied props with kit running with brushless Tornado 3536 1050kv on 3s lipo. Any recommendations of what to go for would be helpful. Thanks

5 years ago by alan50

Response

Re: Brushless Launch

Can I enquire What you are using?

5 years ago by Little-Charlie

Forum

Tug towing

The Decaperm 6v geared is 1:2.75. And very high torque, so it ought to swing a pretty big prop. Measure the prop diameter when you get home as well, also the number of blades. Have you considered experimenting with different s? That can radically change a boat's performance with little effort. Props can be expensive, but you can buy a few cheap ones, or borrow some from a club colleague for experiment. Either increase the diameter or the pitch (or both!) if possible, or go for a 4-bladed one rather than 3-bladed.... I don't know about a Kv/torque relationship - the key distinction is inrunner (high speed/low torque) vs outrunner (high torque/lower speed). Although that is a very general statement, and almost certainly untrue for some motors. KV is a measure of how many revs per volt you can expect. So an 800KV would give you 4800 revs at 6v - not a lot, though that depends on the prop, of course. I normally go for around 1000Kv, and run at 7.2v. Voltage is important for a brushed motor - the brush gear is designed for a particular voltage and will wear badly with increased volts. Brushless do not have this problem, and can run on a wide variety of voltages. Running at 24v is quite possible... The ESC you want for a brushless is simply one that can handle the maximum current your motor will draw - which you can either look up or measure with a Watt Meter. The key concern I usually have with brushless motors is thermal. They are normally designed for aircraft use, where they will get lots of air cooling, and we are putting them in sealed enclosures. Unless you want to water cool, I would suggest running a brushless well down below maximum power, to keep the temperature down. So overspec it, or run with a lower than maximum voltage...

5 years ago by DodgyGeezer

Forum

Motor, speed controller

All got off ebay. The drone boys use this sort of thing extensively. Go there and google the items below. I have added approximate current prices - but I can recall getting some items considerably cheaper.... FPV Mini Digital Video Camera - about £6 Eachine RC832 Boscam 5.8G 48CH FPV Receiver Combo - 5.8Ghz Tx and Rx - about £14.80 7 inch Professional FPV Aerial Photography Monitor For Ground Station - about £17.50 FPV-Pro-DVR-Mini-Video-Audio-Recorder - about £11.30 Plastic-FPV-PT-Pan-Tilt-Camera-Platform - 99p! I also got an extra stick - about £10, a nice plastic box - about £25(!), and various connectors, switches, etc. The box contains a gel battery for the video, which can power the main R/C transmitter down the connector line - that's what the buttons and voltmeter on the panel are for... Note that the video transmitter runs hot - most of them seem to - which is fine on a drone, but thermal control needs some consideration on a boat. You can see a little heat-sink that I added.... P.S. Oh, and you'll need to arrange a 180 deg servo for the panning... P.P.S. You might want to consider a clover-leaf aerial. That enables what they call 'circular polarity' transmission, which is really useful for drones when the transmitting aerial is performing contortions in the air. For boats, a vertical aerial pumping out vertically-polarised waves may suffer from 'bounce' off the water surface, which turns the reflected waves horizontal. But these are very cheap anyway, and can be experimented with - a bit like different s...

5 years ago by DodgyGeezer

Directory

Maersk Master

Maersk Master, scale 1/50. Dimensions, 168x38cm, weight 54kg 1 main pitch controlled (100mm) 2 azimuth thrusters (50mm) and 2 bow thrusters(44mm). Full function, winches, towing pins, lights, fifi, radars,

5 years ago by maersk-topper

Blog

Cooling the motor – update.

I’m grateful to mturpin013 for commenting that he considered using the adaptor supplied with the Turnigy motor as it prompted me to retrieve mine from the box and adapt it to secure the fan on the end of the motor. I cut off the threaded shaft from the prop adaptor and the end was ground flat and then I placed it on the end of the motor stub and used a scriber through the bolt holes to mark the positions on the flange of the fan. The fan was then removed and the holes drilled through and opened up to 3mm and then it was a simple matter to put the fan back on the motor and attach the new piece to the motor using the three 2.5mm cap head screws which are supplied with the prop adaptor. I think this is a far better ‘engineering’ solution to securing the fan to the rotor than a spot of CA. Because the addition of the fan was so straightforward and effective I have decided to implement it on the model anyway so I cut an opening through the end panel of the motor cover and put some stainless steel mesh over that to finish it. The motor is now connected to the ESC and I have done some tests with the motor running and I’m delighted to report that there’s a very healthy airflow through the motor cover 😁👍. It turns out that my modification is not unique at all and credit is due to reilly4 who did something similar to the twin motors on one of his boats long before I came up with the idea. He posted a ‘photo of his boat when replying to mturpin013 on the subject of servo mounts. Take a look at the motors in his picture!

5 years ago by robbob

Forum

Props - dumb question?

I'm just starting to try to "tune" my boat by playing about with s but I've hit a real newbie question: When suppliers talk about a prop being right- or left- handed (presumably that it is designed to spin clockwise/anticlockwise) are they talking about the view of the prop from the front or rear of the boat? Viewed from the rear, I need a prop that spins anti-clockwise - so is that LH? (or is it RH?) Thanks for not laughing (too much)! Ian

5 years ago by IanD

Forum

Props - dumb question?

The down side of prop rotation is that the Europeans use one method of defining it and the Americans use another - and they are contradictory. From the Prop-Shop site "Please note that rotation is based on the British and American standard (viewing the boat from the stern) which is the opposite to that in Germany." See https://www.modelboatmayhem.co.uk/forum/index.php/topic,35415.msg418661.html?PHPSESSID=svi2h5353cc8fjds8h7krcqnh0#msg418661

5 years ago by DodgyGeezer

Forum

S

If you want to use a 4mm shaft, you will need to ream the bearings to fit. Cheers Colin.

5 years ago by Colin H

Forum

S

Thinking of trying to make my own brass s. Has anybody any suggestions on the best construction techniques?

6 years ago by Rowen

Forum

S

looking for a 30mm prop but with 4ba thread anybody help or can i fit a 4mm thread as the 4ba uses a 3.60 rod or can i fit a 4mm prop and shaft 😊

5 years ago by jacko

Forum

s

Looking at the stern of the boat and you have 2 rudders. The port prop should be counter clockwise and the starboard one clockwise.If you have only one rudder then the port is clockwise and the starboard one is counter clockwise.

5 years ago by Donnieboy

Forum

s

Hello ! If you have 2 props on your boat , and one are right and one are left going, on wich side should they be mounted ?? clockwise or counter clockwise .

5 years ago by jugge

Forum

de Mist Naval Tug

Hi Glynn Thanks for your response. I was hoping that the dreaded words "Voith Schneider" would not come up as I have no way to engineer or buy a VSP (even looked in "Graupner" site but no info on buying units and I think it will break the pensioners bank anyway! This is my first contemplated tug build so would be interested if the model tug Guys would perhaps advise what they do when the dreaded 2 words come up...do they cheat a little below the surface and substitute other propulsion sources when a VSP would be "true scale"? Glynn, what Dorbyl built SA tugs do you have knowledge off that are not VSP equipped? I think the other older Simonstown Naval tug is the "de Nuys" but I presume she will also be Voith Schneider driven. Regards and Happy New Year to you and all on MB's.

5 years ago by Joburg-sailor

Media

Electric Barbarella

Ahoy Maties! it's been a long time since my last posting. Happy 2019! I just completed my new scratch-built boat "Electric Barbarella". I tried to recreate (with some liberties) one of my favorite boats of all time, the 30-footer Chris Craft Sportsman built during the 1970s. it measures 24 X 8.5 inches. it is powered with a 9.6 NiMH 4200 mAh battery "nunchuck" pack (like the one used for paintball guns), brushless motor attached to a 30A Mtroniks Hydra controller and a 30mm M4 3-bladed brass . The hull (my own on-the-go design) was made out of Balsa wood which later I fiberglassed. For the superstructure I utilized 2mm ABS plastic sheet material. To my surprise the boat turned to be a very stable and forgiving platform. I really feel a very close connection to this vessel as it is my first own hull design.😁

5 years ago by Krampus

Blog

Plumbing the water-cooling for the ESC

The HobbyKing ESC I’m using has the facility for water cooling and as it will be in an enclosed location without any free ventilation it seems sensible to utilise this feature. To keep the water circuit as short as possible I will put the pickup just behind the and the exhaust on the stern but as the boat has a bulkhead just in front of the stern skin I need to make an access hole through it to allow me to secure the nut on the stern skin. I made a hole through the bulkhead large enough to get a socket on the nut and reinforced the hole with a ply plate, similarly I reinforced the inside of the stern skin where the outlet passes through it. When I was happy that the arrangement worked and I could attach the hoses and securing clips easily I glued and pinned the stern skin to the hull. The water pickup is a standard one that is readily available but it’s supplied with overly large and ugly fixing nuts, the inside one is of no consequence but I thought that the outer one needed smartening up so I put it on a threaded rod and locked it in place with another nut and put that into the chuck of a drill and used a file to re-shape the nut to a pleasing taper….who needs a lathe......😜 I had to reduce the height of the inner keel former as the pickup tube is not long enough to get a good fixing with the internal nut, as the inner keel is balsa I fitted a ply reinforcing plate to spread the load. The last ‘photo shows the location of the ESC, main battery fuse and receiver. The hoses will be secured to the ESC with spring clips throughout. I found that the silicone tube I use tends to kink rather easily if the radius of a bend is too small and I found it necessary to form a tight spring coil around the piece that loops the water back through the ESC to prevent this happening.

5 years ago by robbob

Blog

1-35 Scale Schenllboot By TeeJay

Hi all for the second blog report on the schnellboot I am going to go over the rudder a shaft assembly in more detail. The first stage was to make the rudders which were made of brass ,and having taken note of what has been said about the increase in size needed for the kit by other members I have increased the size of the rudders by 50% so that they have more effect and hopefully the boat will be more agile .I fitted 3mm treaded rod on to the rudder and in a 4mm flanged tube to reinforce the brass rod. The second stage was to make and fit 5mm flanged tube in the location for the rudders in the boat, these were made to be above the water line and will be sealed in place to reduce the possibility of leaks. These were fitted to a rudder platform inside the boat which was fitted to the kit moulding for the rubbing strip that runs the length on the boat and secured by making resin blocks which were fitted with computer extension nuts. which were then superglue in place to secure the rudder platform. The rudders were then fitted in place and held in position with the tiller collars which were made from 8mm rod and fitted the tiller arms and locked in place with 3mm computer screws and ni-lock nuts, a connecting plate was then fitted to connect the three tillers together, I also fitted rubberised washers to seal the rudder tubes. The third stage was to make the supports. The centre support was a direct copy of the kit part made of brass and fitted to the kit with a plate and screws (this plate and the rudder plate were made from galvanised steel) and will sealed with resin after the I test the boat for leaks. The port and starboard supports were made by taking the kit parts and cutting them in have along the joint line or mould seam this gave me a template ,which I used to make cross-section segments but I did alter the template by increasing the boss diameter to 10mm and extending the support legs so that the finished support could be fitted through the hull (the picture of these show the mk1 version where I forgot to allow for the 4mm prop shaft which has a 6mm tube) any way the boss of these segments were drilled out with a 7mm drill and a length of 7mm brass tube fitted through the boss to assemble the segments, all of which were coated in soldering flux at this stage of the assembly which were riveted at both ends to hold it all together during soldering, after soldering the supports were then filed to the size and shape to resemble the kit parts as close as possible and fitted to the hull using a superglue and talcum powder mix and then I cast resin around the extensions to secure the prop supports in place. The fourth stage is the shaft housing for the centre housing I place a brass rod in a plastic straw and place in position in hull and using resin I sealed the hull with the rod in place this gave me a pilot hole for the centre prop shaft after I removed the brass rod. For the port and starboard shafts I used the kit parts which had hole place when assembled, this when I reinforced the housings ,the centre housing I glue 2mm of plasticard on each side and for the port and starboard I made a brass tube shroud which covered the housings which left gaps between the kit part and the brass which was filled by casting resin in the gap this increased the diameter to 10 mm so that there were little chance of breaking throw with the drill and finished these off by fill-in the outside with body filler and sanded to shape and finish . I then drilled through the pilot hole in the housings using very long extended drills and a wheel brace ( if I had use a power drill the heat would have melted the plastic of the kit and may have caused problems) I drill the shaft housings out 6mm them filed them out with 6mm file so that I could insert a length of 6mm brass tube. After all this was done I fitted a flanged bush made from 7mm tube and 2mm brass plate turned to 11mm to the ends or the shaft housings. And now it is time I must ask for some help could anyone advise me on the length of shafts, I know I can use a 300mm shaft for the centre shaft, but port and starboard will have to be longer. and I also need advice on selecting the motors, I want to use 4mm prop shaft with 35mm s. Any opinions welcome.

6 years ago by teejay

Blog

HMS BRAVE BORDERER

Finally the new brass s arrived, delayed about a month in one of Canada's regular postal disruptions. After minor modifications to the boss profile (the brass are more streamlined and thus longer than nylon) to give clearance with the rudder leading edges, they were easily installed. Could now refit the electrical equipment previously removed to get access to the shaft couplings. Inevitably took the opportunity to make “improvements”, so then could not get anything to work! After much frustration determined the problem was not from my improvements, but from the cheap and nasty slide switches provided with ESCs. These must have got damp during the test runs and corroded internally. Suggest when using these switches they be consigned to the garbage and replaced with proper toggle ones. Had decided to use the centre brushed motor/ for manoeuvring and low speed operation and then the outer brushless for high speed. Brushless ESCs do not modulate smoothly and motor operation is erratic. This was particularly evident when going from forward to reverse and vice versa. Using a lever control Tx, it was also easy to inadvertently operate the brushless control along with the brushed making the model response unpredictable. After some thinking, decided to insert a small relay into each of the white signal wires for the brushless motor ESCs. These relays would be controlled by a RC switch operated by another channel on the Rx. Hoping this way the brushless motors could be switched on and off whenever desired. The two relays would retain the ESCs as separate circuits and avoid any interference between them. The idea worked, can now operate the brushed motor confidently knowing the brushless will not be inadvertently triggered. This means low speed manoeuvers can be gently undertaken using the modulation and control ability of the brushless motors and, by selecting the auxiliary control, can add the high speed capability of the brushless. Am also hoping that when the Li-Pos trigger the low voltage cut-outs in the ESCs, this will retain a “get-home” facility on the brushed motor as that ESC operates independently. Much to look forward to when next on the water.

5 years ago by Rowen

Media

Ashes the scratch built Motor Torpedo Boat

I found this hull at thingiverse last year. I printed the hull from a local shop and rest was handmade. Firstly I bought a 2426 4200kv brushless 2-3s which was too powerful and too heavy for the boat size. The length is 38cm. And the 30Amp esc was also too big for it's size. After that I tried small 180 brushed motor with 20A brushed esc w/brake. it was perfect (still it's heavy😂). The bridge and deck is made by 1.75mm pvc,torpedos are made of wooden pencil. Small battery space takes a 2s 500mah lipo. 30mm 3blade . YouTube video link is here: https://youtu.be/KZdmZ8_Z0IE

6 years ago by Sakibian

Response

BRAVE BORDERER - BRUSHLESS SUMMARY

The pump was installed to give positive water flow even when stationary. Felt this would ensure cooling under most conditions. The plumbing is quite torturous and suspected there might be a significant head drop in the circuit. With the wisdom of hindsight, probably overkill; the water scoop between s may prove adequate.

6 years ago by Rowen

Blog

1-35 scale S100 schennllboot

Hi all for the second blog report on the schenllboot I am going to go over the rudder an shaft assembly in more detail. The first stage was to make the rudders which were made of brass ,and having taken note of what has been said about the increase in size needed for the kit by other members I have increased the size of the rudders by 50% so that they have more effect and hopefully the boat will be more agile .I fitted 3mm treaded rod on to the rudder and in a 4mm flanged tube to reinforce the brass rod. The second stage was to make and fit 5mm flanged tube in the location for the rudders in the boat , these were made to be above the water line and will be sealed in place to reduce the possibility of leaks. These were fitted to a rudder platform inside the boat which was fitted to the kit moulding for the rubbing strip that runs the length on the boat and secured by making resin blocks which were fitted with computer extension nuts .which were then superglue in place to secure the rudder platform. The rudders were then fitted in place and held in position with the tiller collars which were made from 8mm rod and fitted the tiller arms and locked in place with 3mm computer screws and ni-lock nuts, a connecting plate was then fitted to connect the three tillers together, I also fitted rubberised washers to seal the rudder tubes. The third stage was to make the supports. The centre support was a direct copy of the kit part made of brass and fitted to the kit with a plate and screws (this plate and the rudder plate were made from galvanised steel)and will sealed with resin after the I test the boat for leaks. The port and starboard supports were made by taking the kit parts and cutting them in have along the joint line or mould seam this gave me a template ,which I used to make cross-section segments but I did alter the template by increasing the boss diameter to 10mm and extending the support legs so that the finished support could be fitted through the hull (the picture of these show the mk1 version where I forgot to allow for the 4mm prop shaft which has a 6mm tube) any way the boss of these segments were drilled out with a 7mm drill and a length of 7mm brass tube fitted through the boss to assemble the segments, all of which were coated in soldering flux at this stage of the assembly which were riveted at both ends to hold it all together during soldering, after soldering the supports were then filed to the size and shape to resemble the kit parts as close as possible and fitted to the hull using a superglue and talcum power mix and then I cast resin around the extensions to secure the prop supports in place. The forth stage is the shaft housing for the centre housing I place a brass rod in a plastic straw and place in position in hull and using resin I sealed the hull with the rod in place this gave me a pilot hole for the centre prop shaft after I removed the brass rod. For the port and starboard shafts I used the kit parts which had hole place when assembled, this when I reinforced the housings ,the centre housing I glue 2mm of plasticard on each side and for the port and starboard I made a brass tube shroud which covered the housings which left gaps between the kit part and the brass which was filled by casting resin in the gap this increased the diameter to 10 mm so that there were little chance of breaking throw with the drill and finished these off by fill-in the outside with body filler and sanded to shape and finish . I then drilled through the pilot hole in the housings using very long extended drills and a wheel brace ( if I had use a power drill the heat would have melted the plastic of the kit and may have caused problems) I drill the shaft housings out 6mm them filed them out with 6mm file so that I could insert a length of 6mm brass tube. After all this was done I fitted a flanged bush made from 7mm tube and 2mm brass plate turned to 11mm to the ends or the shaft housings. And now it is time I have to ask for some help could any one advise me on the length of shafts , I know I can use a 300mm shaft for the centre shaft but port and starboard will have to be longer . and I also need advice on selecting the motors , I want to use 4mm prop shaft with 35mm s. Any opinions welcome.

6 years ago by teejay

Response

Rudders and s

Hello TeeJay, Looks like we are building the same boat, yours looks great and I want to Thank You for asking questions that I had not given thought to , will enjoy following your build and look forward to seeing the first runs .. Bill G.

6 years ago by BW3

Response

Rudders and s

BTW; I copied your above massive text block into a document file and split it up into paragraphs so I could see where you're at! My conclusion: so far so good BUT! You made the one classic mistake of many model boat / ship builders 🤔 You continued the prop shaft tube right back to the and hence you had to make oversize struts to support them. This is fundamental wrong and creates unnecessary work.😉 On real ships, including the Schnellboote, the so called 'stuffing tube' is JUST THAT, it 'stuffs' the shaft through the hull and includes stuffing glands to prevent the ingress of sea water. Outside the hull ONLY the rotating shaft itself continues on through the bearing in the support strut and to the prop. See attached pics of my HMS Belfast as an example. There was actually no reason for you to make oversize strut bearings, simply bushes to match your prop SHAFT not the tube would have been correct. Inside the real ship there is also NO TUBE, only bearings at suitable intervals. They look like gigantic versions of the big ends in your car. Imagine on really big ships, carriers, container ships, bulk tankers etc, with shaft diameters of 1metre or so how big the 'tube' would be, how much weight that would add and how difficult it would be to service and maintain! I've often noticed in posts here that folk confuse shaft and tube, often referring to the whole assembly as 'the shaft'. For convenience we modellers use prop tubes, who wants to fiddle about making a row of internal shaft bearings no one will ever see and will most likely never be really concentric? The downside is that continuing this 'convenience' outside the hull is wrong, adds weight and detracts from the scale appearance of the model. 😭 OK, it's 3am here now so - orf me 'obby 'orse and up (in my case down!) the wooden stairs to Bedfordshire, G'night all, cheers, Doug😎 Re shaft length: What fits fits, what don't don't! Such a question is like asking 'How long is a piece of string?'! If all three motors abreast won't fit you have to decide if the central motor should / will fit fore or aft of the outer motors. Then measure / adjust the shaft length accordingly. Before you start fitting the centre motor check what length shafts are commercially available and adjust your motor fit to suit. Otherwise make your own shafts and tubes to fit as required, as I've started doing cos I got fed up with 'standard sizes' wot don' wanna fit my ship. 🤔 G'night All, cheers, Doug 😎

6 years ago by RNinMunich

Blog

HMS BRAVE BORDERER

The weather has quickly turned colder, giving an excuse to get back to this model. Stripped out much of the interior and the prop. shafts to replace the nylon s with brass. These items all needed removing for painting, so decided to paint the hull before reassembly and then moving onto the superstructure. Fortunately, examining similar naval vessels and several U Tube videos, confirmed the hull as light grey, the deck a darker one of the 50 shades of grey and the lower hull below the waterline black. Used thin Tamiya masking tape to define clean colour separations, followed by regular tape, masked the hull into colour sections and sprayed using “rattle” cans. After the colours applied a light overall Matt coat to subdue any shine. The results are satisfactory. Will now reassemble and move onto building the superstructure and the other fittings. Prior to the season closing decided to experiment with my new Flysky Tx/Rx package, shortly to be fitted to this model. This Tx has a servo limiting function, which was hoping could also be used to restrict ESC output. Would like to make the full speed motor response correspond to full Tx control position. Currently can over power the model; which lifts the stern, causing it to come off the plane and then dig the bow in. Was thinking that if full throttle could be set at around 90% forward control movement and 40% sternwards the model would retain adequate performance, but without being overpowered or very sensitive to control lever movement. As the Brave was not available, tried the idea on my Daman Stan 4207 model. This is brushed motor powered and a good performer. Obviously the settings for the Brave will be different, but at least could try to see if the idea would work – it did! This Tx function is easy to use and adjustments can be made whilst the model is on the water. Once the ideal settings are achieved they can be programmed and then retained in the Tx. Will try this on the Brave when back on the water next Spring.

6 years ago by Rowen

Response

Rudders and s

Agree, Excellent work👍 But do us a favour TJ; hit the return key now and again to break up the text a bit. Such big blocks of continuous sentences are difficult to follow and hard on me old eyeballs 🤓 Where did you get that mini lathe? Looks nice. Cheers, Doug 😎

6 years ago by RNinMunich