John Longford ‘Barbara’

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John Longford ‘Barbara’

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  • #3022
    Stewart Weller
    Participant
      @stewartweller41907
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      #96969
      Stewart Weller
      Participant
        @stewartweller41907

        I have an unfished example of what I Believe from the plans for I that I have not seen for a very very long time 'Barbara' and a bit of googleing comes up with photos of a Bassett Lowke model designed by John Langford that look very much like it. My example was started by my grandfather in the 1950's The Hull is largely completed, it is painted and the deck planks looks to have been inked in? (I will get photos, working from memory) the super structure was built and painted but no windows fitted or mast/rigging, there is a hole for a funnel but this was either never made or lost at some time before the 1970s (when I first remember it gathering dust) It was originally intended to have a 4 cylinder side valve petrol engine which my father was building (we still have that as well) but the engine never really managed to make any more power than it needed to idle and was never fitted although the engine mountings are present in the hull. My plan is to go electric with it. I have a lot of spare radio gear from years of RC cars and aircraft but as I recall a prop shaft tube is present in the hull but no prop shaft or rudders so I am going to need help on what motor/prop combinations to use, I also have a collection of speed controllers, mechanical and electronic. Given the chances of finding the original set of plans I have bought a new set.

        So the first questions is what motor and prop should I be looking for with enough power to get it up on the planes? Battery type may also be a consideration at it would need to sit nicely at rest

        #97025
        ashley needham
        Participant
          @ashleyneedham69188

          Hi Stewart and welcome to the forum.

          As with all these sorts of questions, pictures and measurements/type of construction are needed.

          Is this a miniature side valve engine? ?

          it may be easiest to change them propshaft tube for something new as it will be imperial and tricky to find a shaft to suit especially in stainless steel which is what you want.

          Ashley

          #97032
          Richard Simpson
          Participant
            @richardsimpson88330

            Welcome to the forum Stewart. As Ashley says you are much better with a matching shaft and tube if at all possible, especially when you are dealing with an old tube. If it is too difficult to remove then you might have to consider making and fitting new bushes to suit a modern shaft. Have a chat with "Prop Shop" for options or have a look at the shaft and tubes available from "Cornwall Model Boats."

            Pictures would definately be a huge help in identifying motor requirements. You need to look at creating an album, into which you can load your own pictures, then you can use those pictures in any post you make on the forum.

            #97036
            Ray Wood 3
            Participant
              @raywood3

              Hi Stuart,

              The engine you have there sounds like a Seal 15cc side valve four stroke designed by Edgar T Westbury in the 50's quite popular for straight running boat competitions in the 50's & 60's, could be be quite collectable/valuable

              Regards Ray

              #97039
              Dave Cooper 6
              Participant
                @davecooper6

                Hi

                You mention that you have loads of old radio gear from cars and aircraft. Just as a note, you can use 27MHz in boats but not 35 MHz (this is reserved for aircraft). However, you may still have to change crystals if someone else is on your frequency…

                A better bet these days would be to plump for the new 2.4 GHz technology where there is virtually no risk of interference from other modellers. Prices for these sets have come tumbling down in recent years and are now very affordable.

                I still use my 'old' gear for bench testing and prototyping new ideas, so, there's no need to throw it away.

                Why not give us a list of what you've got, including ESC's, Motors, Batteries etc and we can go from there ?

                Regards,

                Dave

                #97152
                Stewart Weller
                Participant
                  @stewartweller41907

                  barbara2.jpgWell I have recovered the Boat from the back of Dad's garage.. and so have now got some photos.. it is of what I would describe as of traditional construction, that is made of wood, with a keel and formers with mostly planks on the side, it is over a metre long.. The prop shaft will not present any problems the Myford 7 in the corner will see to that! It did turn out to have a prop on it as well.

                  Radios are mostly Futaba, a LOT of M-Series stuff along with some later 35MHz challengers and Gold 7ch and a Feild Force 7barbara1.jpg. Disliked the newer 2.4 stuff so much (it seems the build quality on things like the sticks is now dreadful) that I converted one of my old M-6 TXs to 2.4 the multi model memory was not really something I was ever likely to use. I have more Glow plug motors than I would care to list! there is also a 'Taplin Twin' marine version in a aerokits crash tender (silimar size to this) originally a diesel it was converted to Glow Fuel with home made heads. But I would like to keep that where it is.. I have an assortment of '540' sized brushed motors. Ideally I would like this one to go brusheless having just replaced my OS FS40 in my Super Sixty with a 870KV turnigy motor.

                  The Hull appears to have a lot of weight in the bow, I am guessing my grandfather weighted it down to make it sit level?

                  #97156
                  Stewart Weller
                  Participant
                    @stewartweller41907

                    Oh having looked up the 15cc Seal engine, that is it! although Dad's one has magneto ignition.. (don't ask how I know!)

                    #97169
                    Dave Cooper 6
                    Participant
                      @davecooper6

                      Hi Stewart – looks like you have a good selection of kit and skills there – Have Myford will travel….! (I think Ray's got one of those).

                      Looking at the hull, it seems to be more of a 'planer' than displacement ? That being so, brushless with a good ESC and LiPo pack is probably the way to go. The experts on here will advise on motor size /Kv rating etc. as my experience is limited to small service craft with brushed motors and, electric gliders with brushless.

                      As you're into 'modding' radios, have you tried Hall-effect sticks – they are much smoother than the normal fare ?

                      On a final note – will it fit in the bath ? A floatation test should tell if any serious internal hull work is necessary before you fit it out with new equipment. Also, you can check out the trim fore-and-aft and any listing that may be present.

                      Have fun,

                      Dave

                      #97171
                      Stewart Weller
                      Participant
                        @stewartweller41907

                        I have already checked for leaks by putting it in the bath!, and found none. As it is it does sit level (well level enough for my eye!). I think the first plan of action is to sort out the rudders, It has two tubes for them fitted but they were either never installed or have been lost in the intervening 6 decades. This may require the deployment of the lathe to make the rudder shafts fit (Given the two rudders is there anything else to look at? is there an ackerman angle for boats?). Then work on fitting the radio gear, do I keep the servo rods short or fit all the electrics in a box aft of where the funnel will be (When that is fitted are there smoke generators?)

                        The idea is to get all the internal hardware worked out and test fitted at least before sorting out the paintwork, The hull was very nicely painted, and in most places still is, but the action of the seasons on the wood over the decades has taken its toll and there is some cracking which is to be expected I guess and some of the joints have become visible as a result, I am tempted to rub it down and fill. Later questions will involve reinstating the deck planking that was drawn on but will be lost when it is rubbed down

                        Stewart

                        #97176
                        Dave Cooper 6
                        Participant
                          @davecooper6

                          I'm not aware of any Ackermann effect on boats – after all, we're dealing with fluids not contact with solid surfaces like roads…. (I do, however, run some anti-Ackermann on my Le Mans-style sportscar but that's another story !).

                          For the rudder bushings I would use Sif bronze as it's self-lubricating, or, a good quality nylon bush (just a personal preference). The bronze should turn nicely on the lathe…

                          Geometry-wise, I'd go for a parallel linkage, about 30 deg's deflection either side of mid-ships. Fit control horns having a row of holes so you can fine-tune the throw. I think most people drive one rudder from the steering servo and 'slave' the other off it via an adjustable linkage rod. Use a little Vaseline (or, similar) top and bottom of the rudder posts to help with water-intrusion and lubrication.

                          Let the experts advise you on paint-cracking /hull preparation as I've no real experience here. (A few close-up photos would help here I expect).

                          Dave

                          #97344
                          Dave Cooper 6
                          Participant
                            @davecooper6

                            Just a quick note :

                            By 'Ackerman effect' ( /geometry), I think Stewart is referring to the rudder on the inside of the turn moving through a greater angle than the rudder on the outside of the turn. This is usually used on road vehicles to reduce tyre scrub when cornering.

                            Stewart – this would be possible via a different type of adjustable linkage. I doubt there would be much benefit though. If you have a RC buggy in your stock of old models you could use this for inspiration if you wanted to experiment….

                            Regards,

                            Dave

                            #97346
                            Richard Simpson
                            Participant
                              @richardsimpson88330

                              This is a really good explanation:

                              Ackermann

                              I remember it being a big selling point on my Airfix slot racing system when I was around 10 years old!

                              I suspect that with twin rudders the advantages are negligible and probably not worth the amount of effort and complicated linkages required to achieve it.

                              #97419
                              Dave Cooper 6
                              Participant
                                @davecooper6

                                A very interesting and informative article Richard.

                                I note that quite a few of the texts referred to were written before Aerodynamics and Downforce became the 'main /dominant' variable.

                                Also, many racing boats are now using aerofoils (in one form or another) to good effect…..I suppose if they were also using widely-spaced rudders / z-drives, or whatever, then Ackerman may have a role to play ?

                                #97431
                                Stewart Weller
                                Participant
                                  @stewartweller41907

                                  Hi, My thoughts were that while tyre scrub is not an issue was that without some sort of 'ackerman' geometry with twin rudders the 'scrub' would manifest as unwanted drag in the turn. There is no extra linkage above and beyond that which a twin rudder setup would normally have, but the levers would not be parralel but at an angle toward (or away) from each other (this being refered to as the ackermann angle. Probably not an issue with a boat of this type

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