Once the rudder, propeller and shafts were installed, the position of the motors could be established. A light aluminium bracket to hold all three was fabricated and bonded to the hull. Due to the high speed capability of the brushless motors, particular attention was paid to alignment. Also kept to the shortest prop. shafts that could be fitted to avoid whipping. Although the motor type might change, whatever is best will require a sound electrical installation as the current requirements for each brushless motor could reach 50 Amps. Wired each motor and ESC separately with its own dedicated fuse to give the maximum system protection. There is an extra fuse section allocated for auxiliary circuits, such as a cooling water pump and lights. Will try the original planned layout of 3 x 2835 motors with 30mm propellers and a 2S Li-Po battery first. Am hoping the reduced voltage will also make these motors more tractable. For the test program the three ESCs will be each controlled from an individual Rx channel. Once the final layout is determined, a more sophisticated and flexible control system can be installed. To minimize ballast, particularly around the stern, the battery will be housed as far into the bow as possible. After the test runs the final battery type, size and location can be established. To assess performance, hope to try both 2 and 3S Li-Po batteries. Planning to reduce heat build up by fitting cooling water jackets to the motors, these are easiest to instal at this stage so the wiring or mounts are not disturbed in the future. Have not decided the layout for the water circuit yet, but this easily can be added later. All that is needed now is the ice to melt off our local lakes so tests can commence.
Slow progress recently, partly due to snow(!) but also because I have had some engineering to catch up on. Anyway, I have cut and fitted but not completed shaping the bow and stern blocks, fitted the prop shaft and fabricated the rudder assembly. This was silver soldered using a little piece of 3mm silver steel and sheet and channel brass. Yes, the keel looks a bit of a mess in this area but I am going to cover the ply with mahogany veneer to match the planking when I have completed that, and of course it will all be painted below the water-line. I also made a rough cradle to keep the boat steady while working on it - to be replaced with a posh one when everything is done!
So here we go again! I have decided to give other projects a rest for a time in favour of this little gem. Pick up off eBay for less than £100 NIB posted, couldnt resist! Its the Dumas (kit no:1203) 44' Coast Guard Lifeboat. I dont know if this kit is still produced by Dumas and having looked at the Die cutting of the parts, certainly seems like an old kit? However, I love my building and the challenges, so I am sure it will turn out nice at the end. Finished length 33". I shall be converting this to a RNLI Waveney Class Lifeboat and will possibly go with 44-003 named "Khami" which was based in Great Yarmouth and Gorleston, which is local to me here in Suffolk. Sadly very little turns up on this boat via Google, but at some stage may pop out to the Great Yarmouth Lifeboat station and see if I can hunt anymore info on her. I shall not be using the recommended Dumas running gear for 2 reasons, 1st its a geared set-up (I am going with MFA540 brushed direct drive) and the cost of over £150! Photos show the box artwork, plans and the included wood. Last photo shows my electrics less propshafts and props that are on order. Note the Star Wars 3.75" figures that with poetic licence could be painted to represent crew. However, at this point the model is approx 1;16 scale and the figures would be 1:18 scale so maybe too small. There are 1:16 scale lifeboat figures available but pricey? My one issue at this point is going to battery choice? do I go with a small 6v lead acid or perhaps 2 Tamiya type 7.2v NIMH in series. anyone who has built anything like this may want to advise. LIPO not an option as the Mtroniks ESC do not support LIPO. Space inside the hull may also be an issue? Another issue is going to be fabricating some propshaft struts for the rear next to the props. There is quite a bit of prop shaft exposed outside the hull, so these would be integral to support and strength of the propshafts. Is there anything available off the shelf (they are included in the running gear set, but dont seem to be available on there own) of do I need to fabricate from brass tube and sheet/strip brass?
Very nice but I think our friend's prop tube comes through the keelson .The wedge shaped keel extension piece to which the tube is secured so that support would not suit. However a "U" tube or two could be fabricated and wrapped round tube and secured to keelson with a couple of small screws and a good glue.Ali .copper or brass would do. Brass best to avoid electrolytic corrosion with the brass prop tube. Also brass screws. BTW just looking at shaft is not enough to check if straight. Hold to a known straight edge or rolled on flat surface. This will show up even the slightest curvature by allowing light under the ends when rolling with the fingers in the middle. Or slide a piece of paper (cigarette paper best ) against ends .If it goes under there is a bend in the test piece 👍
Hi Roy I agree well made prop shafts such as supplied by Raboesch are excellent. Personally I make my own to scale and length as I have the materials and lathes with which to fabricate them. My experience over many years is that over time the bearings and shafts wear and will require replacing at some time. I have used oiling tubes and stuffing boxes for best results, the latter make small leak repairs simple, but if the prop end bearing has worn it needs replacing. Our last club sailing waters were saline and I had to replace the bearings in all the models I sailed there. I used to wash the model hulls after every sail but it didn't help. I use a thick oil in the tubes.
Hi Novagsio Do tread carefully if you intend to use Westbourne as there has been posts on this and other sites regarding their poor service level and lack of advertised stock. Canabus has a build blog mdlbt.com/31424 Not sure exactly what fittings you require but Reade Models may be able to help as they supported fittings for many of the kits produced alongside the Precedent range. http://reademodels.com If you are looking for the window frames then you may need to fabricate from liteply, or if you have a 3D printer source have some fabricated.
OK! I admit (temporary😉) defeat 🤔 Yep, it's the weight and size of the frames of conventional speakers that are the problem. That's what attracted me to 'Paul's' mini transducers in the first place. Southampton goes back on the back-burner, will settle for RX, ESC and battery upgrade for now. But possibilities noted in my Log Book. Must do a Payload Test sometime. Re Build Blogs; I think I'd better finish the Sea Scout first before this all gets out of hand! 😲 next step; fabricate new propshaft and mount the brushless. In between perhaps something on the PT 109. Have all the ingredients assembled now except stern gun; Decision: 20mm Oerlikon or 40mm? Pics on the net show both at various times. Cheers Doug 😎
Hi Steve Your FPB is coming along nicely. Mine is still untouched but seeing your progress make me think I should start the refurb. Looking at the gun and other fittings I do believe the casings could best be fabricated on a 3D printer if you have some drawings and dimensions. I will be a Haydock and our stand is very near to Mike's gun stand so hope to see you when you visit. Dave
That's a fair comment but you could say the same about buying a pre-moulded hull or a kit. But, take it to its logical conclusion, do you fabricate your own plywood? Cultivate, and harvest your own balsa wood/bass wood/mahogany? Be a purist if that's what you want but is it right to sneer at others who find their own path to tread?
this will be the motor to be used. Honda GP200 4HP 4 stroke gasoline motor. i opted to detach the gas tank so that i can lay it somewhere on the boat. i just modified the fuel line. i also remove the integrated kill switch(red latch) from the motor so that i can lay it somewhere on the boat. i will just find a way to attach a servo into it. maybe some modification on the switch will do the work. hopefully. i also removed the stock muffler, i need to fabricate a new muffler so that it blows on the stern(back) portion of the main hull.
After a successful first attempt at planking the tow-hook deck I then did the same to the mid deck. I placed a 5mm border of maple with mitred corners, but I stepped it out around the forward cabin access door so that the completed deck panel can be dropped and slid into place beneath the door threshold. The planking was placed working out from the centre line to keep the spacing even, and when the CA had fully set the black plasticard ‘caulking’ was trimmed flush with a sharp chisel and the whole surface sanded smooth. There is a small detail on this deck which is identified on the Vosper drawing as a ‘fuel tank sounding’, a sort of dipstick access point I suppose. This part is not supplied in the metal fittings kit so and I fabricated this from a piece of 10mm brass tube with a plasticard insert to replicate the detail. This was then painted metallic silver and let into the deck after cutting a 10mm diameter hole through the planking. To cut this hole I used a short piece of 10mm thin wall brass tube with a sharp edge filed on its internal bore so that it acted as a sort of ‘cookie cutter’ and it produced a neat and accurately sized hole in the deck planking. The ‘step’ formed by the door and frame was painted to match the door and then the complete deck panel sprayed with several coats of satin lacquer for the final finish. I'm getting the hang of this planking lark so confidence is high as I move on to tackle the far more challenging cockpit deck 🤔