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Mast assembly

The supplied mast is of white metal and although OK it has a number of minus points for me. 1- The mast does not lend its self to being hinged. 2- It really needs navigation light on top and the supplied casting is not suitable for this. 3- wiring needs to be hidden, not easy with the casting 4- it’s quite heavy Having said all that it’s ok if you don’t want my wish list. So on with the manufacture of a replica, I chose brass as the preferred material because it’s easy to silver and soft solder. The main legs are made from 6mm round tube, which I squeezed in my machine vice to an oval shape to look like the castings, each of the ends were then squeezed again at 90 degrees to allow then to join to the cross mid-section. I made some brass inserts for the hinged end from 2mm brass sheet, which are bent by 25 degrees to allow the hinge mechanism to sit at 90 degrees to the cabin roof, these are drilled and tapped 8BA. These pieces actually block the end of the oval tube and need to have a 2mm slot milled in them to allow the wires to exit the tube; these are soft soldered in place later. Two feet were made from two pieces of 2mm brass plate the base plate being slotted to accept the upright and finally silver soldered together. (A point here for silver soldering is to use as little solder as possible and allow it to flow with the heat around the joint this means that no filing is needed. I find it’s also good practice to quench the part when nearly cool to break the glass like residue of the flux then just steel wool is required to clean the parts). The feet upstands were then drilled 8BA clearance and the base fixing holes drilled the same size. The cross mid-section is made from 1mm brass sheet and is bent through 360 degrees whilst placing a 6mm round bar in the centre to create a hole for the top mast. A small wooden former was used as the piece was pressed together in the machine vice, this was then silver soldered to give and then filed to shape. This piece has to accommodate the wires passing through, so again a 2mm slot is milled from each leg location to the centre to create passage up to the top mast. The top mast is just stock tubing which then has a turned top with four 5mm holes machined at 90 degrees to accommodate the LED. This is a 5mm Flat top wide angle LED this will direct the light out of the four holes. Finally the cross piece, again stock tube with small ball finials at each end soft soldered in place and tapped 10 BA for the pulley blocks. All pieces now made, it’s time to assemble the parts using a combination of soft soldering and epoxy resin. The wire that I used was silicon sheaved, and when I soldered the legs to the mid-section and lower hinge piece I made sure there was enough wire to pull through to check if the process had damaged the wire, but it hadn’t. So having soldered the LED, the top was epoxied to the upper tube and the tube epoxied to the mid-section. Finally the mid-section was filled using Milliput but first putting some Vaseline on the wires to avoid them being stuck should I ever have to rewire the unit. Next the cross beam was added and epoxied in place. The bottom of the legs looked plain compared with the cast version so I have made some thin gauge brass covers with mock bolts as per the original. The whole assembly was cleaned up ready for a first coat of etch primer, and white primer, followed later with a final coat of appliance white

5 years ago by mturpin013

Directory

(Yacht) DMI 'Pirat''

Classic modell, in the 70's sold under the name DMI pirat. a full wooden sailboat without RC controls. the keel was extended to improve . In the 90's the wooden strips from the hull were so dried out, that I had to fill it complete with epoxy and sprayed the uniform 'baby blue'color. After a long period in the attic , it saw daylight again and the sails needed to be replaced. Now it is a static model with sailing capacities. (7/10)

5 years ago by Smaragd

Response

coastguard

So far so good Northumbrian,👍 although I might have placed the batteries lower in the hull to lower the CoG and thus improve (roll-rate reduction) 😉 Look forward to the superstructure updates, looking for some tips for my fish cutter superstructure rebuild 😁😉 Cheers, Doug

6 years ago by RNinMunich

Forum

Your ideas on how to stabilize a flat-bottomed freighter.

After adding the needed weights to bring this freighter down to a loaded ship water line, the model rocks n rolls. It needs either a keel or exterior fins. What is your experience? Please share with us.

6 years ago by Ronald

Forum

Your ideas on how to stabilize a flat-bottomed freighter.

https://www.marineinsight.com/naval-architecture/roll-stabilization-systems/amp/ I chose to add a bilge keel to begin with in the search of .

6 years ago by Ronald

Blog

HMS BRAVE BORDERER

Adjusted the transom flaps and reprogrammed the ESCs to the softest start settings, retested. Until now, the test runs did not have the duration or to really examine what was happening. Using 3 S batteries acceleration is rapid and a is plane quickly achieved. However, as the acceleration continues and speed increases, the bow digs in. A cloud of spray then surrounds the model as the plane is lost. Brushless motors do not modulate as smoothly as brushed and adjusting power tends to be erratic or exaggerated. This is a scale model and the propeller shaft angles are per the plans. The thrust from the propeller has two components, horizontal and vertical. The horizontal propels the vessel forward. However, the vertical component forces the stern upwards and, correspondingly, the bow down. Have moved as much weight as possible towards the stern to counteract this, limited by maintaining the correct displacement and waterline. The easiest solution is to reduce motor power, decreasing both speed and the lifting component. Decided to retry the 2S batteries as they give reduced power. A plane is again achieved, but as the motor response is more docile, it can be controlled. if the speed gets too high the bow lowers, as before, but the motor output can be more easily adjusted. Spent a pleasant half hour or so with the vessel accelerating onto and off a nice, controllable plane. Much less spray and drama than with 3S and much more controllable. Have now decided to revise plans and use 2S rather than 3 batteries. A further advantage is the motor noise is muted and now sounds more like a gas turbine than a dental drill! Finally feeling comfortable with the model. Will thus shelve further building until the late fall when sailing in Canada concludes. Want to enjoy the rest of my fleet in the meantime! Will summarize my experiences with brushless motors in another blog shortly for the benefits of others contemplating their use. After restarting the model will resurrect periodic build blogs to advise progress.

6 years ago by Rowen

Response

Vickers Vedette 1/96 scale

Many thanks for your kind words, I've not sailed her yet, only test tank and had to up the water line a little bit for more , I also scaled up the plans to true 1/96 as the plan is around 1/100, the 1/96 fittings I bought from fleetscale were out of scale to the plan, and using the 1.1 water line length noted in the magazine article.

6 years ago by f4u7

Forum

Windows, stoopid question.

Doug, sorry, I should have answered you last time on that. A good impression of a dummy screw can be made in aluminium with a piece of tube sharpened on the end so it looks like a miniature leather punch. Obviously better if you can do it with something you've done in the lathe, in steel, but you don't have one. SO....PM me your postal and I will send you something I will knock up for you tomorrow in steel. That will last you into your dotage, when you will be found dribbling into the geraniums with this little tool in your mitts making impressions on the window cills of Frau Schmutterputz's Home for Englische Modelbauen. You will be able to "sharpen" it buy running it round on a stone lightly, rolling it as you draw it backwards. Can't add to Squire Turpin's words at all. I have a slide tailstock on my wee Taig lathe which makes screw forming easy as the thread takes the tap/die as it wants it, square and true. The piercing saw has clamps for much finer blades rather than the relatively big fret saw blades which generally have a pin at the ends. Sometimes you'll break a blade at one end. Then the adju makes sense as you just re work the length and re-use the broken blade. Tight wads like me appreciate such things. Car booked in tomorrow for repairs. About £300, so not as bad as I thought it might be. it's passed for the last two years. Busy boy today as I sprayed the Crash Tender grey on its upper works and by the looks of it it just needs a few areas of fine filler and a rub down on the toe rails and one more coat then it'll be ready for the gloss sides and the hull proper. Then I even used my brand new saw to mitre the corners of the topping to Chris's new garden pond casing. it's a stand up one to save our backs. So now, I am gonna sit and watch shite telly, even shiter than normal as it is all infested by ball kickers playing grown ups and failing miserably . G'night. Martin

6 years ago by Westquay

Forum

Marblehead Sailboat

All done and ready to sail. I took it to an outdoor swimming pool at a neighbours and did a Sytems check; ; All was fine and I suspect this is going Go like a greyhound on the lake! Put in a new sail winch robbe #8336; rudder servo is HiTec HS-322HD

6 years ago by Ronald

Response

Sea Scout 'Jessica' Sea Trial - at last!

Interesting Canabus! Not quite what you recommended last year 😲 if you now think the Propdrive 1000kV has "no guts" why did you recommend it to me?? Thanks for spoiling my mood 🤔 As far as I'm concerned you just devalued your currency! I'm happy with her as she is, balance and is OK and performance, endurance vs current drain is much more lively than she ever was in 55 years.😊 After all, she's supposed to be a Broads Cruiser and not an Offshore Power Boat.😉 I'm not into racing either. From time to time I'll fiddle with fittings detail and cockpit on Jessica. Time to get on with other projects now. Doug 😎

6 years ago by RNinMunich

Blog

H.M.S BRAVE BORDERER

Looks like everything is set for the first open water test. Sun is shining, ice has gone and water smooth. Intention is to start the open water test program with a repeat of the pool test, except this time with everything wired correctly; the load cell positioned so the “pull” is more horizontal and ballast available to hold the propellers underwater if necessary. Hope these improvements help reading . To modify the “pull” arrangements, wrapped a light cord around the propeller shaft struts and fed the loose end above the transom shelf and out over the stern. The load cell was hooked into this and then tied to a fixed grating on the pond side. Started by measuring the electrical requirements for each of the three motors and the propeller bollard pull, using the 2 S battery. Found the bollard pull was up slightly at almost 3 lbs per propeller. Probably because they were now held at a greater depth in the water. Also blew several 20A fuses, so fitted 30, which seem to work. A series of runs showed adequate performance with plenty of spray, although the bow did not lift much onto the plane. The forefoot did raise almost above the water surface. Then tried a 3S battery. Although this was much heavier, the performance improved dramatically. The bollard pull was up to almost 18 lbs per shaft. The bow still did not lift much to a plane, although the forefoot was almost clear of the water at full speed. The battery was located just back from the bow, so it is suspected that it held the bow down. The impact of the transom flap down angle could also hold the bow down, but have decided to leave as is for the time being and avoid the temptation of making too many adjustment at once. Whilst it is still too early to draw definite conclusions, it seems as if a 3S battery will be required. The model sustained some slight damage due to the test arrangements, so will repair that and also fit the 2 bladed Hi Speed propellers. Will then repeat the program and report. Should be able to draw some definite conclusions then on the best power train. Neither of the batteries used, neither the 2 S nor the 3S are ones I would choose for this model. As a result the capacities and weights are not ideal. That must also be remembered in future deliberations.

6 years ago by Rowen

Response

Genesis 9000

Hi Peter very unusual problem with the switch😲 You could temporarily replace it with a bullet connector to continue trials. Glue one end down so that you can quickly unplug the battery one handed. OR: simply short circuit the switch and use the fuse as the 'switch'!? Boat looks a little heavy / tail heavy? Maybe shift some weight a little forward to give more ? Happy trialling, cheers Doug 😎

6 years ago by RNinMunich

Blog

H.M.S. BRAVE BORDERER

An unexpected opportunity arose to try the unfinished hull in a small pool. Whilst the performance envelope could not be explored, was able to try and measure operating parameters and get a “feel” for the model. Used an electronic scale and a combination voltmeter/ammeter/wattmeter to measure propeller thrust /bollard pull and motor power requirements. if it is necessary to fit different drivetrain components, or a 3S cell this will serve as the baseline. The model floated levelly and well above the waterline. At about 8 volts the motors drew around 20 amps each at full speed; so only about 35% of the potential output capacity was being used. Tested each motor individually and measured the bollard pull at just over 2 lbs. A considerable amount of spray and wash was created making stable readings difficult. For further testing, will add ballast at the stern to hold the propellers further underwater. Should help reading . Currently using 20 A fuses; which as one failed seem marginal. For sustained use think 25 or 30 Amp better. With these high-speed, low torque motors establishing the “dry” propeller rotation is deceptive. Found one motor to be reversed! Nevertheless, the model accelerates quickly and is sensitive to engine speed movements. Left the pool with a list of modifications to make before assessing the installation properly on an adequate body of water. Some conclusions can be made though. if it is necessary to add a second cell this needs to be located around midships, not in the bow or stern. Still hoping a 3S cell will not be necessary and that 2S may be adequate. The suggestion to do testing using the bare hull with a minimum of detail was a good one. For a models with a sophisticated power train think this is a good approach. Nothing worse that finishing a boat just to find the performance disappointing, then have to to rip it apart to make major modifications or adjustments!

6 years ago by Rowen

Response

Devil in the detail!

I'm with you there Skydive 👍What Boatshed means is the part of the rudder in front of the stock. Thinks: are you building an Offshore Power Boat or a scale Lifeboat? If the former then follow Boatshed's recommendation. If the latter and the rudder is 'scale' then leave it alone. Any braking effect, which usually is only significant in a fast racing boat model or other fast planing types, can be diminished by reducing the rudder servo throw at the TX. One should also consider how the original behaved, maybe they did 'dig in' maybe not. There has to be a reason why such rudders were developed, and surely not just to annoy modellers 😁 One more minor point that struck me - Ouch 😭 Your prop struts! "not that it provides a huge amount of support but adds to the scale appearance." Even in a model they can be important. To help reduce potential whipping of the propshaft, especially if the model is overpowered. Actually in the originals they were vital, especially in larger vessels. The purpose of these struts, in larger vessels 'A' frames, is to provide support to the end of the shaft which carries the prop weighing several tons and, more important, to carry the bearing for the outer end of the shaft! Actually in the originals the shaft tube, or 'Stuffing Box' would not extend significantly beyond the hull. Thus the strut or A frame was vital for the shaft end bearing, fitted immediately in front of the prop for maximum . Attached pics of my HMS Belfast (sorry don't 'ave nutt'n smaller with this feature🤔) show the arrangement. Have witnessed such construction in various shipyards around the world. Last one in UK was the first T45, quite an experience! 😲 In the end she's your boat, if it feels good do it! 😉 I would leave the rudder alone if it is 'as fitted'. 👍 I make my struts and A frames from brass sheet and tube. Cheers Doug 😎 PS Stick with the brass Donnie! 👍

6 years ago by RNinMunich

Forum

Sea Queen Spray Rails

Yes some more recent models, predominantly made for racing do have moulded rails along the bottom. Two reasons, one to add strength, especially if of thin material and secondly to provide lateral at the high speeds encountered. When the Aerokits were designed in around 1960s plastic was not commonly available to hobbyists and models were designed using wood/plywood and the originals did not even have spray rails fitted. The running gear was also heavy and bulky resulting in much heavier models than are possible today so the hulls did not plane so easily and the rails were not needed for most models. Technology can now turn out hulls in bulk using extruded and formed plastic and the rails add to the strength to help keep the shape. You can see this on most plastic packaging used for consumer items

6 years ago by Dave M

Forum

Sea Queen Spray Rails

My Sea Commander "Jaydee" has spray rails about 3/16th inch square. Have a look at the Aerokits photo gallery. There is a picture of it out of the water and some in action. I believe rails are a must for in the turns when going at speed as well as helping lift the boat onto plane. Ian

6 years ago by IanD

Response

M.V. TEAKWOOD

Sure looks like it Mark! I'm beginning to wonder if this is to be a display model only, and the bolts are for the pedestals!? Or maybe to bolt on a ' keel' when sailing? Doug 😎

7 years ago by RNinMunich

Forum

propshafts

Hi Dave, Yep, agree, to a certain extent. I have also had surprising results with 385 / 400 sizes; for instance with my 110cm heavy and cramped submarine. On the surface it outruns most boy racers 😁 Not exactly scale but all good fun. A little down angle on the forward planes and it throws up a beautiful handlebar moustache of water 😊 Not too much angle at speed or it sticks it's tail in the air 😲 No, the main question was that Fred already has the 700s so I simply suggested a decent match, 5mm shaft and so on. If he wants to spend on more motors fine. the the 3mm shaft would surely save weight, mostly through the smaller tube. Don't know the rest of the detail of the boat; beam, draft, safe waterline etc, but I would have thought a 3 footer would have a reasonable carrying capacity, like my 3 and 4 foot warships. Most of those run on multiple Speed 600s. And there I have the usual warship high length to beam ratio and associated problems! Like I said; he pays his money and takes his choice. Personally I would give it a whirl with the 700s since they are in the box! Maybe though with a 3 or 4mm shaft and appropriate coupling so he can adapt later if he wants to. Would still think a pair of 35 props would do the trick. Whatever, have fun Fred. Look forward to the Sea trials Report! (Wrote, read and commented enough of 'em in my old job!) Cheers Doug 😎 Oh no! Yet another thunderstorm just started, my terrace is already swamped 🤔

7 years ago by RNinMunich

Forum

ESC POWER

Hi All, Diodes: - Trillium is correct of course, although some ESCs have a 6V BEC. Some RXs work off 3 - 3.7V for 1S LiPo operation in small boats. Not the case here. 😉 As for I would guess that you get what you pay for! Cheap unstable, expensive stable!? Higher current versions with a switched supply? But the diodes are the only way to achieve the situation posed in the original question. Personally I wouldn't do it for all the reasons listed above. In RHs case seems to me the port ESC fault shot the BEC and robbed the RX of it's power supply resulting in total loss of control.😡 That's what shut down the stbd motor (ESC went Fail Safe) and why I asked if the rudder still responded; "No answer came the stern reply" 🤔 Why it may have failed Dave-M knows better than I, more practice! 👍 Cheers Doug 😎

7 years ago by RNinMunich

Response

Dirty Deeds

Thank you, AllenA! Well, no science behind the running time. As long as I run at low speeds it just happens everything seems fine. But when I put the throttle down... then all is over within 15 minutes or so. I pretty much stick to the same power layout. 540 motors with 30A controllers, 2000 or higher mAh capacity and 35mm or 40mm props and 4mm shafts. Dirty Deeds is a bit special. I was on my learning curve (I'm still there!) so due to a novice error I used a 2mm shaft so I had to get a special propeller and a big mean battery (kind of a Viagra approach). So, I had a 4-bladed 35mm propeller bored for the 2mm shaft and a 10.8v 4000 mah battery pack. A bit in the heavy side but it gave the boat nice . I can achieve better running time with Lipos, but I'm an old-fashioned guy still concerned with the maintenance Lipos involve and do appreciate a bit more of the weight offered by NIHMs, not to mention I'm a cheap guy (LOL). Something that really worked for me is the choice of propellers. I noticed a remarkable run-time difference between plastic and metal (yes, more expensive) propellers, but it is well-spent money. Other boats I have run with 9.8v 2000 mAH batteries achieving almost 50 min at low speeds, which is OK with some of my models for realistic ride purposes. Here I have my two "inspirational" pics.

7 years ago by Krampus

Response

Aeronaut Pilot

Thanks guys! And yes AllenA I was surprised too! Funnily enough when both props were working there wasn’t too much difference in top speed, probably around 2 or 3 mph however the acceleration was much faster with two as was the ! (And yes my minor spelling typo!😂 missed that one!) and thanks John, I’m really looking forward to putting the deck on! The rubbing strake and some fenders have just arrived so time to make some progress, however I’m am going away tomorrow on an army cadet camp (don’t worry I’m in the Navy section!! 😂) so will not be able to do anything for a week. Anyway I’ll try and make some more progress and look forward to reporting back again! Hopefully some running in the next video! Yours T

7 years ago by Skipper44

Blog

Shelduck

Installing the Radio gear. Planking the Deck in 6mm x 2mm and .5mm Mahogany vertically used as "Caulking". A lot of brass pins.. !... Lead Keel, about 10lb; in weight. it was supposed to be "Let into" the keel, but a lot of extra work, decided to screw it to the bottom, hoping this would give it more having a deeper keel. Regards Muddy ....

7 years ago by muddy

Forum

What battery do you choose?

Strangely no one has answered an important part of your original question !? 🤔 How to calculate running time! Simply put; divide the capacity of the battery in amp-hours (AH) by the current in amps (A) drawn by the load. AH/A = H !! Step 1; measure the max current drawn A(max) by the motor under load; i.e. full speed ahead in water - hang on tight!. if not possible then use the max current data of the motor at the voltage you intend to use. Step 2; check the capacity of your battery; usually given in mAH for some peculiar reason! Divide by 1000 to get AH. Divide the capacity in AH by the max current in A =A(max). Result is the theoretical time that the fully charged battery can deliver the current required; i.e. runtime at full speed. Theoretical because in practise the usable capacity will be a bit less than nominal depending on the age and condition of the battery, ambient temperature etc. Also you won't want to completely discharge the battery; it won't like it 😡 Step 3; measure current at a mid-range throttle setting 'cruising' - A(cruise). Again divide capacity AH by A(cruise). result is 'cruising time in hours. if measuring not possible use the motor current data given at maximum efficiency. Should give a reasonable approximation. Example: motor current at full speed = 10A. Battery capacity 7000mAH = 7AH. Max theoretical runtime at full speed = 7/10Hr. Approx 42 minutes. Cruising current; 5A. Cruising time = 7/5Hr = 1.4Hr. Approx. 84 minutes. Use the highest capacity batt. you can get in without upsetting etc.! If you need ballast use a bigger battery; then you have 'payload ballast' instead of JUST ballast. Minimise current drain by; ensuring drive train is perfectly inline, well lubricated, prop is as small as possible for the desired performance (trial and error!). Hope this lot helps, not space science but a few basic rules! 😉 Happy sailing and lots o' fun. Cheers Doug 😎

7 years ago by RNinMunich

Response

WPB 110

Very nice vessel, well done. From the turning radius and , suspect the stabilizer fins operate. Would appreciate details; particularly dimensions and weight. Rather hoping my Damen Stan 4207 which is a similar craft will perform as well. That model is untried as yet.

7 years ago by Rowen

Forum

from the Philippines

@figtree7nts - I'm planning to build a USV type of boat with general specs; *catamaran type hull (not yet sure of the dimensions but based on my own research maybe L- 58", beam - 20" for each hull) *long range (20-30kms) *cruise speed (3-4 km/h) on board components *FPV cameras (at least 2) *motors (not sure what type but I'm leaning more on electric than gas) *GPS and antennas for long range capability. i want to start with the basics first and probably will include add-ons in navigation in the future. i just want to have a reliable running platform at first. it will be used in salt water environment. I'm thinking of a twin hull to make it more stable out in the waters. it will not be deployed in rough weather but i think it would be better to have a twin hull for . I already have a Taranis Tx and Rx which i used for simulators before. thanks for link on the website. indeed they have lots of stuffs. my only concern is they are based in England so i will pay for multiple export fees until it reaches the Philippines(sad reality) From England they will have it delivered in the US(virtual address) then from the US to my country through a local courier. I cannot let the store deliver it directly to the Philippines because the Customs here will surely rain me with custom's taxes and it will require me to personally pick up the items. but i'll give it a try first and see the difference. it will be my first time to order on UK based websites.

7 years ago by analyst

Response

Finished Sections and Top Stringer

Looking good. 👍 Same construction method I used for my H Class destroyer. Appreciate the size problem, typical length to beam ratio of destroyers ca 9to1. Gives speed but affects . Where did I read quotes like "she rolls on wet grass"! I chose 1:72 for Hotspur giving 136x12cm to play with. Don't despair; I squeezed in 2x500 brushed plus switching for lights, 2 sound boards, loud speaker, smoke generator and rotation for radar and main guns. Sure you can get 2x385 motors, or small brushless in 😉 Keep the top weight down though, or with the Buckley's 8.4 to 1 length to beam ratio you might have a near heart attack on the first fast turn, like I did with Hotspur 🤔 Keep up the good work, look forward to the video .... Cheers Doug 😎

7 years ago by RNinMunich

Forum

Richards 48'' Swordsman

Hi good news, I have just checked the area of damage around the shaft exit, on further investigation there is no delamination👍 i think I will re stick the ply sheet down then stregthen the area with modeling tissue and resin. i am fotunate that the wood strips that run from the bow to the stern (i think they give the model grip and straight line ,help i do not know the correct term), give a natural line to patch upto.i will stengthen the interior with wood strips again resind in.

7 years ago by rmwall107

Blog

DAMEN STAN 4207

Finished the structural work and painted the partially assembled model. Environment Canada has advised winter is now officially half over, so have decided to suspend further efforts on the detail components and focus on repairs and upgrades to my fleet in anticipation of the forthcoming sailing season. Readers may recall concerns over the weight of this model and . The final trial test showed the performance at 7.2 volts was satisfactory and that using two 5,000 mA NiMh stick cell sets in parallel gave a running duration in excess of a hour. After trawling E Bay found a source of 10,000mA NiMH C size cells. Unfortunately the seller would not advise the weigh of these cells, eventually decided to purchase some for a trial. After the usual delivery period the cells arrived, so made up a 7.2 volt set using plastic 2 x 4 C cell battery holders. The total weight of the assembly was 8 oz less that the two stick cells! if the duration works out this will contribute significantly to efforts to minimize weight. Think the effect on will be little as it was good during the earlier tests.

7 years ago by Rowen

Forum

Skeg on King Fisher

I plan to add this Skeg to the KingFisher to protect and add to the shaft. Does anyone see a problem with the design?

7 years ago by Ronald

Media

Northlight Clyde Puffer

I have just completed my Puffer and am quite pleased with the outcome. The components are quite good but do need a bit of fettling but this is what our hobby is about. This is my third Caldercraft build so I am used to their quality and sparse instructions.   As usual for Caldercraft you need to have your thinking cap on as the A0 plan and the 'instruction book' do not match up but of course they do expect you to have a little bit of experience in model building. it has taken me about 6 months to build working on and off over this time. it has a large hull which is easy to house the motor, ESC, RC and batteries, etc. (I installed 2 lead acid 6 volt batteries, one on each side amidships) which gives and ballast. Being a large deep hull it needs a lot of ballast, even in its short length.I have only tested her in the big white nautical test facility at home so do not know how it will perform on our lake but hope to try it out on Sunday if the weather is set fair. Tried her out Wednesday and she sailed really well - maybe a little more ballast in the bow but not too concerned.

8 years ago by ads90

Blog

DAMEN STAN 4207

After examining the Damen drawings, decided build to a scale of 1:42, giving an overall length of just above 40'. Discussing the project with local enthusiasts established that a model of the Hero class had been built recently, but by working from photographs and that a similar style patrol boat had also been constructed. Experience from these projects showed that both weight and were critical. The actual vessel does not draw much water and has considerable top hamper. These features have an effect on . Did not want to increase the hull depth, although this is a well proven technique to help address these issues. Concluded it would be necessary to build lightly and to keep the weight low. To help control , plan to make the complex mast structure as light as possible using aluminum and styrene sections and then make the hull stabilizers operable, as in the real vessel. These should help offset any tendency for extreme heeling in manoevers. Have considered slinging the ballast/batteries under the hull to increase righting moment and will make provision for this during construction. This feature will not be activated unless trials show it necessary as it adds a non-standard feature, even if it is below the water-line. Efforts to minimize weight will also determine the battery type, construction techniques and materials.

8 years ago by Rowen

Forum

Smoke Generator

As for my next build I am looking at HMS Devonshire, the first Royal Navy Guided Missile Destroyer. My last Build HMS Blake (See Post) has rotating Radar that was my limit. I would like to push the boat as to say and add some smoke from both funnels. I have seen some smoke generators on offer and was wondering about as the water evaporates up the funnel. I will be looking to rotate the two main Aerial on the ship and was wondering about moving turrets - Or would that be step to far this will be my four build.http://model-boats.com/sys_files/graphics/smileys/S09.gif

8 years ago by martinsperring070558

Forum

Smoke Generator

Okay, issue resolved I presume I could have one unit to service the two funnels?

8 years ago by martinsperring070558

Forum

Smoke Generator

I have seen reports that the units using oil (or "distillate") leaves deposits, although I have not experienced that problem. They also smell. Glycol is used in the fog units you see in theatrical shows, so I don't think they will leave a deposit. I have not experienced a problem. The SMU unit will hold about 350ml of water, but can only use about half of it (the top half :-). So the weight reduces but the centre of gravity also lowers.

8 years ago by Trillium

Forum

Smoke Generator

Many thanks for both replies, I was looking at the water version - I have been told the Glycol version leaves deposits on the superstructure. The real question was , if you have a full take of water - Possible irrelevant as the tank is small would it affect the of the ship?

8 years ago by martinsperring070558

Forum

Sailing a straight line

Thanks for all the thoughts and ideas. The shafts are parallel, but the angle of the photo may suggest otherwise. The rudders are not exactly parallel, but I find it hard to believe that the amount of mismatch can be the cause of the problem. I have been careful to do any tests when the water is calm and there is no wind, and run them in both directions ( as would be done on a measured mile), to try and eliminate extraneous influences. (Doesn't mean that's been entirely succesful, but enough to convince me they are minor effects.) I had previously contacted Max (4clubs) and knew that his model did not have this problem, so he couldn't help me at the time. I now learn that the Hoylake club has 3 models of this vessel and none have this problem. These models all have the rudders inline with the props, (so not true to the prototype, but each to his own.) This points to the offset rudders being a major contributor. I still plan to increase the size of the rudders, to see if that improves the directional .

8 years ago by Trillium

Forum

new steamer

Filled a length of copper tube with lead, tied it on Amazing! Sits at the right height and all problems solved. incredible how moving the weight under the hull transforms the . All I have to do now is work out how to fix it preferably so it is removeable, come on guys any bright ideas? Roger

8 years ago by shavings

Response

PT 301 (Snuffy Smith)

Motor has been left insitu, Prop shaft found to be vibrating and has now been fixed. Hull stripped back to bare wood and repainted in camoflage. Spray rails fixed to the hull have made a big difference to . Not on the original Aerokits drawings. Can now concentrate on Deans Cossack. Plenty of sheet lead for but looks good.

8 years ago by Gabby

Forum

About the Waterline on Serenity

OOOHH your sailing close to the wind, if she sees this your dead!!!! Had a close look at the hull, being long and narrow you will get it rolling, if you can alter the ballast, making it long and thin right into the keel line this will reduce the roll IE fitted between the bulkheads and along side the keel, possibly with lead shot the finer the better so it will compact down as low as possible. An alternative would be a detachable keel, screwed to the hull on the outside, so lowering the moment of roll below the hull. My Amsterdam suffers the same problem, this was helped by adding bilge keels to the hull, the real Amsterdam was a real pig reports say she could roll on a mill pond, caused by the round bilge hull having no grip or once the roll starts Mark

8 years ago by jarvo

Blog

H.M.S BULLDOG / BEAGLE

Had the opportunity to do a trail ballast run. As a result, made some modifications and added weight. To get almost down to the lower boot topping line, a total ballast weight of 5 lbs is needed. This is made up of about 2 lbs of lead dispersed from the bow to the first bulkhead, (approx 7" sternwards) and then two 6v SLA batteries (1 3/4" lbs ea), the first located just forward of the superstructure and the second just to the rear. This gives a fairly good trim, further trim ballast will be required when all the deck fittings are added. Both batteries are now laid flat to reduce the C of G and improve . The vessel is wired with both 6 volt batteries in series to give 12 v. Had been warned that at 12 volts the model is overpowered, which can now confirm. Unfortunately 12 volts is needed for the radar scanner and lights. Have thus ordered a voltage reducer so the motor voltage can be adjusted to something in the 6 volt range. Back now to building deck furniture and making the many finishing touches

8 years ago by Rowen

Response

PT109

HI Seaman Blucher - shouldn't that be Admiral? Are you named after Gebhard Leberecht von Blücher of WW1 warship fame? Anyway, thanks for your comments, although my intention was never to put anyone off building these boats. I have looked at other peoples PT109s and seem to recognised the same problems that mine exhibits. Mine can look quite alarming when turning to starboard - I can't help thinking it's going to 'dig in' and submarine, even after the turn signal is cancelled. I have to admit that I probably installed the rudder a few degees off vertical - not much really, about 3-4 degrees - and wondered if it was that. I should get around to straightening it up one day. I have tried multiples of lower batteries and more ballast up front or at the stern but nothing has improved it. The boat isn't plastic, it's plywood and you can see its very robust construction on the build blog I did for it on this site. Your idea of a false keel or keels might work but seems very drastic when you think how many of these kits have been made, and presumably they don't suffer from the same problems that mine does. At least I haven't heard of it if they do. I have also thought about fitting trim tabs which I expect will fight any tendency to roll the boat at speed. Obviously more work is needed but my Perkasa works so well the PT109 is on the shelf for the moment!

8 years ago by Lauriem

Response

PT109

Your comments regarding are very helpful. Given that free-board is low, there is obviously not much can be done with ballast to create better , you have put me off this particular type of model. Just as a wild idea though, do you think maybe a couple of false keels below the waterline running the underside length of the hull to just before where it curves upwards for the bows would help in stopping the skid and roll with every twitch of the rudder? I have seen these used on model speedboats to give slightly better lateral without interfering with speed. Obviously, with being plastic and fairly lightweight, the boat would want to flip if pushed too hard in a turn, as would its full size counterpart, but hopefully these would reduce the amount of roll in slower turns.

8 years ago by blucher

Directory

(Tug Boat) St Canutte

This model is a Billings plank on frame kit, usually as a static model, as this was originally. I fibre glass coated the inside to seal it. There are full working lights and a smoke generator. Bilge keels were added to help and the rudder made slightly oversize to improve steering. Normally only sailed on calm waters. (Motor: MFA 380) (ESC: Electronise) (8/10)

8 years ago by Derek

Forum

straight running

Haverlock is accurate when he says that 'remote' control is forbidden - which implies that controls integrated into the boat's structure ARE allowed. I believe, for instance, that pendulum controls were experimented with in the early years, for both boats and aircraft, to provide some . However, I suspect that he will run up against some aggressive interpretation if he wants to use modern electronics. For a start, the GPS system certainly relies on satellite communications, and these are 'remote', so I guess that would be banned. Modern electronics could easily identify the target poles, by optical, sound or radar beams, and then direct the boat accordingly, but the echos from these signals would be 'remote', and hence could be banned under the current rule. I suspect that a fully autonomous internal gyro-based system which maintained a selected heading would be OK under the rules, but that would not offer the improved target accuracy that GPS could offer, and might be no better than a well-designed hull. The skill in straight running is to predict the amount of offset drift which occurs, and if the rules are aggressively interpreted to ban any external/remote 'communication' (including the boat taking external sightings of some kind) then it is hard to see a big benefit from currently available technology....

9 years ago by DodgyGeezer

Media

Lulonga , river quarterwheeler

Today Lulonga River steamer passed further navigation tests after replacing the ESC.(the new ESC are from HK...), working well, The electronics work reliably, problems with again, but this time with a transverse . Since the superstructures that I built are quite heavy, and the model also has a flat bottom, so setting up a balanced position is very sensitive, and somehow I can not. I try to stick around under the bottom of the line model, additional load. Perhaps it will also help the exchange wheel https://youtu.be/tr59Ipalx9g http://youtu.be/T-GNZ3Qzq1A some more Lulonga photos (also other than the model) can be found atl) can be found at > http://tomarack.rajce.idnes.cz/RC_model_Lulonga

9 years ago by tomarack

Forum

Paddle wheeler lists

Hi, I recomend repeatedly to put your question to paddleducks.There you could certainly find modelers, who have experience with models paddlesteamers and can help with your problem. My model Lulonga has two independently driven wheel, each has its own ESC. Driving is a double ... classic rudder control but especially ESC ..drive back and forth is controlled via Throttle position on transmitter, using a Y cable. This allows the trimmer to adjust the speed .. optimally 90-150 rpm. Adjusting the speed of motors to the same value terms set by a trimmer on the transmitter. Own control direction is a mix throttle with "ailerons" channel (1 and 3). This allows you to change the speed of each wheel independently on Throttle position and thereby control the direction of navigation. . it is even possible to change the sense of rotation, so that the wheel rotates against each other. This ship turns almost on the spot. A wheel diameter of my Lulonga is 150 mm. A similar problem like yours, I did not met personally. next ..and perhaps your main problem may be that you can not mechanically practically ensuring that each wheel had the same number of turns .. Each motor has the same input voltage slightly different speeds .. and without trim it is Impossible to adjust. Additionally .. the question is the size of the model. As regard to speed of paddle wheels (rpm) I think it is practically negligible, if any blade touches the water before the blade wheel on the opposite side of the model.... maybe you need a proper trim then. Paddle wheel drive model has its own specific problems. The main problem is, that the model has a closed paddlebox . it happens that the water, instead of being driven backward, is suctioned into paddlebox ,rotates similarly as in the pump , and model practically do not move. Help .. proper area of holes in the paddlebox side panels (at least). Lulonga has louvers fixed at the back of paddlebox . My first paddleboat was australian type steamer Ned Kelly(live steam propulsion 115 cm long hull, hull breadth about 20 cm without paddleboxes). Her superstructure was too high and and a relatively small breadth of the hull caused great in while sailing - the breadth recommended at least 25 cm. When I removed the superstructure, Improved , then model sailed with straight keel very exemplary. had the wheel of simple construction made of plywood, very effective .. though not as nice as yours at your model. I have model ,at present , quarterwheeler Lulonga(see gallery, the long article about model building you can find at Paddleducks) . She has also the paddlewheels of my homemade construction, nevertheless very heavy. Her stern sits very deep in the water The model is about 75 cm long, but due to the structure and shape of the hull would be good if and its length was at least 85 cm. I have a problem lengthwise balancing model. Tom

9 years ago by tomarack

Directory

(Naval Ship) PT109

Recently completed, this DUMAS kit is a bit of a disappointment in that its - or lack of it - looks quite frightening sometimes. it can take on an alarming list even in a straight line although it takes up a quite satisfactory 'lean into the corner ' when making a turn. Adding and moving weight around has yet to solve this awkward looking performance and I have yet to buy two batteries so the battery weight can be moved lower and possible more to the rear. Speed is not a problem but there is no way that anything like full throttle can be attempted. There is little freeboard and a list looks very alarming at speed! Any ideas? (Motor: Turnigy Aquastar 3660-1460kV) (ESC: Birdie) (4/10)

9 years ago by Lauriem

Forum

Newbie advice

Starting to build the boat, as static model. Chicken out. My base of operations lol is lough key Ireland. Boat would not be really suitable for the lake. light hull small motor. Adding wieght would help but cancel out any performance. Might just float away, having me do bay watch rescue style, again. No thanks. |_| sank my 2L milk bottle boat 14/16mm hieght boat.

10 years ago by joergn

Forum

Superstructure

HI Mate As its for the superstructure get some Liteply, its about half the weight of normal ply, Just remember keep the weight off, or you will need extra lead in the hull for Mark

10 years ago by jarvo

Forum

Superstructure

HI Squirtgun Is this for sheeting the hull or superstructure? outdoor or marine plywood is much heavier than balsa wood, used on the cabin could cause the boat problems. Mark

10 years ago by jarvo