Model Boat Mayhem
The Shipyard ( Dry Dock ): Builds & Questions => Navy - Military - Battleships: => Topic started by: TurboTyne on July 15, 2014, 03:41:18 pm
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Hello
I am hoping to get some advice regarding my dream of building a model of the WW1 R-class destroyer HMS Rigorous.
I have obtained the plans for this ship from the NMM and am now puzzling over what scale to build it at. My first question concerns the displacement to be expected for a model hull. I gather that theoretically, the displacement of a model equals the displacement of the prototype divided by the scale factor cubed. The prototype had a displacement of 890 – 1222 tons. If the above rule is correct, then, assuming a displacement of 1073 tons, models built to scales of 1:48, 1:60 and 1:72 would have displacements of 21.7, 11.1 and 6.4 lbs respectively. So I am wondering, are the results of this calculation realistic and reliable in practice? i.e. do they form a useful approximate guide to what I should expect in a model?
The M and R-class ships had similar hulls and these were very narrow in proportion to their length. Thus, for the same three scales the lengths and, beams of the hulls would be 69 X 6.7 ins, 55 X 5.4 ins and 46 X 4.4 ins. Of course internal space will be less than this.
I hope to fit steam propulsion so I am inclined to go for the 1:48 scale because of the greater displacement and greater internal space. However, I am a bit worried that with a water-line length of 69 ins, I would end up with something conspicuously big and also awkward to handle. I have little experience with sailing model boats, so any advice will be most welcome.
One further question concerns the propulsion. The original ship had 2 screws driven by separate sets of turbines. However, I will undoubtedly need to drive both from the same engine. Would the fact that both propellers will always turn at equal speeds adversely affect manoeuvrability to any great extent?
Thanks for looking at this.
Regards, Mike
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A further consideration or two (or three!)
1. A length of hull over 53" may be tricky to fit in a typical car (I just measured my backseat!) - make sure what you choose can be transported to the lake!
2. If you run in freshwater your displacement figures may be a bit off - or is it when in saltwater? (I can never remember!)
3. Water doesn't really scale too well. Bearing that in mind, running both shafts at the same speed should be fine, but you may need to increase the size of the rudder arrangement anyway, or have a 'display' rudder - and a larger 'running' rudder - which may just be a sleeve over the display rudder.
A WWI R Class eh? I feel a thumbing through Jane's Fighting Ships coming on!
-Rob
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Hi – my view may differ from others on here – personally, I’d look at the steam plant that you intend to use as this will be the limiting factor for size & weight.
If you have identified your hulls and worked out your approximate displacements, then if you add the weight of the hull, the steam plant, your radio gear & batteries, add some weight for your superstructure & fittings (which will be dependant on your preferred materials and construction methods) then the scale to use may become self-evident.
I would always go bigger if possible because you can use additional lead ballast in the bottom of the hull to deal with any stability and waterline issues.
As mentioned above, the question of size will also be determined by the size of car you have to transport the model around.
In my experience, both props acting as one won’t be too much of a problem unless you want to do tight courses at regattas. The length of the hull will always make a boat that is slightly unresponsive to rudder.
You could cheat a bit and fit a bow-thruster to aid handling, but I get the impression that you’re into accurate scale modelling.
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Thanks for all those 3 points Rob - especially point 2. I had completely forgotten about Plimsoll lines. I just checked this out and it seems that when loaded to the same depth, the weight is about 2.5% less when in fresh water compared to in sea-water at the same temperature.
I must measure my car - although 20 lbs would not be too much for the roof rack maybe?
Thanks, Mike
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hi there Mike
Looking at your profile I noticed that you are a fellow Geordie - I live 9 mile away from your goodself in Sand-dancers country. I am sure you are aware that there are 4 good clubs in the vicinity of the North East - Heaton; Tynemouth; South Shields and Saltwell Park; oh and I forgot about Roker one.... so thats 5.
Heaton and South Shields Clubs are heavily into Steam - as well as yachts; South Shields Club on a Sunday morning have a club - if you ask for either John Neilson or Bob Kirtley - they will be able to guide you through all of your questions regarding stability and building single engine driven twin screws; as they both build steam driven models. Bob will no doubt try and turn you towards flash steam; high speed records or straight running. John has built a very similar model to the one you are building - although it is semi scaled, it looks the part and goes well.
aye
John
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20lbs may be ok with adequate restraints - It would make a heck of a torpedo in an emergency stop otherwise! :-)
Try and make as much of the weight in the hull demountable, so that the actual weight up there on the rack may only be 10 -> 12lbs. When you put the ship in the water, then you can re-add the ballast, and ancillary weight. It makes transport so much easier!
The other factor to consider, is that having weight high up on a car is inefficient and adversely affects handling, much more than when that weight is closer to the C-of-G (both static and dynamic).
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If using a steam plant take into consideration the weight of the water in the boiler which in that hull I would assume is above the waterline.
Bob
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If you have identified your hulls and worked out your approximate displacements, then if you add the weight of the hull, the steam plant, your radio gear & batteries, add some weight for your superstructure & fittings (which will be dependant on your preferred materials and construction methods) then the scale to use may become self-evident.
You could cheat a bit and fit a bow-thruster to aid handling, but I get the impression that you’re into accurate scale modelling.
Thanks for those comments Plastic.
Re: the steam plant, I'm making this myself, so weight is somewhat adjustable within limits of course. But the radio gear is an unknown quantity for me.
Hmm bow thruster is definitely out for me. I'm not too bothered about great performance - main things are that it is reasonably true to scale, floats the right way up and goes at a realsitic looking speed, bearing in mind the R-class ships could do 36 Knots.
Thanks, Mike
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Hi Mike.
commercial fittings are available at 1/72 and 1/48 scales. Could always try and pick up a cheap trailer on Flea bay for the 1/48 model.
frank
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hi there Mike
Looking at your profile I noticed that you are a fellow Geordie - I live 9 mile away from your goodself in Sand-dancers country. I am sure you are aware that there are 4 good clubs in the vicinity of the North East - Heaton; Tynemouth; South Shields and Saltwell Park; oh and I forgot about Roker one.... so thats 5.
Heaton and South Shields Clubs are heavily into Steam - as well as yachts; South Shields Club on a Sunday morning have a club - if you ask for either John Neilson or Bob Kirtley - they will be able to guide you through all of your questions regarding stability and building single engine driven twin screws; as they both build steam driven models. Bob will no doubt try and turn you towards flash steam; high speed records or straight running. John has built a very similar model to the one you are building - although it is semi scaled, it looks the part and goes well.
aye
John
Thanks for that suggestion John. (Sorry to dissappoint but I'm not really a Geordie - but incomer from the South). I am a stones throw from the Heaton club. I was wondering if there are any steam people there. I really should get in touch with them. Actually my steam plant will (hopefully) be flash steam - but electronically controlled rather that flat out racing - along the lines of Flashtwo's Vital Byte. Trouble is my electronics stuff adds to the weight.
Regards, Mike
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If using a steam plant take into consideration the weight of the water in the boiler which in that hull I would assume is above the waterline.
Bob
Thanks Bob. Actually I hope to use my horizontally coiled flash-type boiler, so this should help keep the weight low down - but these ships were not very deep unfortunately. I've read that sometimes people add extra depth to their hulls to help with these issues but I would prefer to keep to scale if possible.
Thanks,, Mike
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Hi Mike.
commercial fittings are available at 1/72 and 1/48 scales. Could always try and pick up a cheap trailer on Flea bay for the 1/48 model.
frank
Have a look at Steve Pickering's website "Chylds Hall Model Shipyard" he does a lot of bits in 1/48th scale for WWI warships.
http://www.chyldshallmodelshipyard.com/ (http://www.chyldshallmodelshipyard.com/)
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HMS Rigorous is a Glasgow boat with three chins will you have smoke coming out them all
frank
http://www.clydesite.co.uk/clydebuilt/viewship.asp?id=2008 (http://www.clydesite.co.uk/clydebuilt/viewship.asp?id=2008)
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HMS Rigorous is a Glasgow boat with three chins will you have smoke coming out them all
frank
http://www.clydesite.co.uk/clydebuilt/viewship.asp?id=2008 (http://www.clydesite.co.uk/clydebuilt/viewship.asp?id=2008)
Hi Frank
Don't know how the internals will pan out yet. Be good to use all three stacks.
But how much smoke actually came from oil-fired boilers? Wasn't it normal to avoid smoke production as much as possible? Trouble is, since a condenser is not going to be feasible, it will probably be white steam that comes out rather than smoke. Still, if I get a boat made at all I'll be pleased.
A trailers a good idea but I only need a trolley since I guess I could push it to the pond from home.
Mike
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Have a look at Steve Pickering's website "Chylds Hall Model Shipyard" he does a lot of bits in 1/48th scale for WWI warships.
http://www.chyldshallmodelshipyard.com/ (http://www.chyldshallmodelshipyard.com/)
They look like a very useful array of fittings. Hmmm, I only hope I eventually get to the stage when I actually need bits like that.
Thanks, Mike
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^ I saw three of these vessels at the weekend in Glasgow. Narrow hulls, but practical. Surely "as big as possible" is the watchword for a steam version?
As for fitting in a car, I can get my 87+" Dreadnought in a Nissan Note, without sweary words and with a whole inch or two left over.
(http://www.noteownersclub.co.uk/forum/uploads/1622/ship1.jpg)
:-))
Andy
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In 1/48 scale it's about 5.5ft give or take
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O.K. the comments so far confirm my inclination to 1:48 scale, (especially the photo of Andy's Dreadnought in a Note).
Thanks very much for all the replies.
But what about my first question - is the estimate of the displacement at 21.7 lbs a reliable, although approximate, guide for planning weight of hull, machinery, superstructure etc?
Regards, Mike
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If you have a copy of the plans at your chosen scale, you can approximate the total expected weight by working out a simplified volume up to the waterline of each compartment created by the bulkheads into a series of separate square boxes and triangular boxes (with a bit of give & take here and there).
If your boat is round under the water, substitute cylinders and cones for boxes.
If you work out the total volume by adding them all together in litres, then that approximates to kilos.
It's not super-accurate but you'll be in the close ball park.
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But what about my first question - is the estimate of the displacement at 21.7 lbs a reliable, although approximate, guide for planning weight of hull, machinery, superstructure etc?
Hi Mike - yes, it is: though to allow a certain "wriggle room" for ballasting I'd be aiming at maybe 75% of that for the all-up build.
Meanwhile, Plastic's suggestion is worth doing, since by estimating the hull volume bulkhead-by-bulkhead you'd be able to roughly calculate out where the centre of bouyancy lies along the keel. That would probably be the ideal point for your boiler: as water is boiled off you'd only get a change in waterline.
Andy
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Mike...........
1. you had previously stated a typical weight of 890 – 1222 tons
2. so let say 1000 tonnes...[assuming displacement tonnes]
3. the answer to understand scale reduction is tonnes divided by the cube root of the scale O0
4. so 1000 divided by 48......divided by 48.... divided by 48 = 9.04 kg
This estimate is based upon the nominal 1000 tonnes.....but clearly confirms your 21.7 lbs is in the ballpark........ :-))
Sorry {-) to mince units of measure...........Derek
PS... the methodology offered by plastic is also the most intelligent estimation/calculation method when the final answer or result was unknown.... :-))
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Thanks a lot for all the further responses.
So for the immediate future, I know I should think about an all in weight of no more than about 17 lbs. but I will, in any case, get the plans out, turn on Excel and follow Plastic's suggestion.
I guess that, at the same time, I could roughly calculate the surface area of the hull and use that to estimate the weight of the empty hull.
Thanks again,
Mike
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Hi Mike, you'll find that the 17lbs goes very quickly when steam is involved!
One thing you'll also need to consider is where the weight is located. Generally, where the boiler is and this is normally controlled where the stack is.
Tony :-))
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Hi Mike, you'll find that the 17lbs goes very quickly when steam is involved!
One thing you'll also need to consider is where the weight is located. Generally, where the boiler is and this is normally controlled where the stack is.
Tony :-))
Hi Tony
Thanks for that comment. Yes, I'm beginning to realise that even at 1:48 scale, I shall have to compromise on the complexity of the steam plant that I install. But I really hope to be able to keep with using an electrically pumped paraffin burner (see thread in Steam R&D) since that gives great control and will allow fuel to be stored anywhere - e.g. low down and in the same location as the war-tanks of the original ship.
Hopefuly the fact that the R-class had three stacks will allow a bit of flexibility in positioning the boiler. It will all be a very slow development process.
Regards Mike
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Ref her displacement, unlike the Merchant Navy, the Royal Navy quoted displacement is her actual weight displacement in water, standard which is no fuel or ordinance and full load which is every item of store. The merchant navy is a measurement of internal cubic capacity and varies according to what type of vessel and classification society.
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I carried out the calculations of hull volume/displacement as suggested by Plastic, although I used a different calculation method. I made a scanned image of the M-class body-plan (i.e. cross-sections) taken from the Admiralty lines drawing. (The NMM does not have lines for the R-class but Admiralty M and R-class ships had basically the same hulls). This image was imported into my CAD software. After checking that the dimensions of the image were accurate I traced over the lines to create line drawings that the CAD programme could analyse. So I ended up with copies of 22 half-sections with each showing a standard water line.
The CAD package is just 2-dimensional (Solid Edge Free 2D) so calculation of volume used an approximation. It was simple to get the programme to calculate the area of each cross-section up to the water line. Next, I calculated the hull volume between each of the 22 sections by multiplying the distance between each pair by the average of the areas of the two sections. Extra estimates were made of the volumes at each end of the hull. Adding up all these volumes and multiplying by the density of water gave a displacement of between 22lbs for freshwater at 20 degC and 22.6 lbs for sea-water at 4 degC .
The admiralty M-class drawings say the displacement is “about 960 tons”. The trial displacements varied from 890 tons (one of the M-class ships) to 1186 tons (the heaviest R-class ship). I do not understand if these values were calculated from weights of everything on board or from measurement of the depth of hulls in the water. Also, I wonder if the differences between ships of the same class were due to differenct loadings or to differences in basic structure.
Using the rule that displacement of a model can be estimated by dividing by the scale factor cubed, a 944 tons displacement at 1:48 scale is 19 lbs and a 1186 ton displacement is 24 lbs. So I was pleased that the value of 22 lb from calculations on the drawings seems to be a reasonably sensible result, falling in just the right range.
Apparently M-class ships were designated as 13 tons per inch, meaning that every 13 tons additional weight caused an alteration in draught of 1 inch. So another way of thinking about this is that between the 890 and 1186 ton trial displacements, the draught would have changed by about 23 ins. At 1:48 scale this is 0.48 ins. However, it seems things were not as simple as this because different yards built hulls with slightly different finished sizes and this would have affected the draught for a given weight.
For me, this was an interesting exercise that has taught me some useful things.
Thanks for all the inputs.
Regards Mike
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I think you're virtually on the money there!
Don't forget that "averaging the areas and multiplying by the distance between those areas" is not (quite) the same as finding the volume of a hull "chunk" - with the hull curving inwards from "wider" to "narrower" areas, the volume enclosed will be somewhat higher than the simple calculation.
...But near enough your 22lbs!
And where (roughly) is the centre of buoyancy along the long axis? (Enquiring minds want to know!)
Andy
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Hi Andy
Thanks for prompting me to do yet more calculations :-) .
This is another aspect I had not thought about. Well, I estimate the centre of buoyancy is about 34.5 ins from the bow (at water line) in a hull with a length of 66 ins to stern post and 67.75 ins overall. i.e. it is about mid-ship.
But what does this mean in practice and is it typical of most ships? e.g. are battleships the same?
I guess I need to arrange for the centre of gravity of the final model to be at the same point?
On the actual ship, this point was just aft of the last (third) boiler and between boilers and the turbines which, I guess, could well coincide with the c of g.
Regards Mike
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Hi does not the meta-centric height come in here?
Very low for battle ships so they have a slow roll for firing the guns and I have read of just 2 feet for a full size battle ship. More for a destroyer to give stability but a some what jerky ride.
regards Roy
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I'm sure metacentric height will be next on the list! O0
Thing is, my Dreadnought's relatively insane beam and little topworks will allow me to model a realistic MH: I'm going to be aiming for a scale 2cm and I'll still get form stability to 66 degrees of list. Meanwhile that skinny destroyer with plenty "up top" (given we tend to build superstructures heavy in order that we can handle them) is always going to be that bit more "delicate". :embarrassed:
Andy
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Hi I have an HMS Dreadnought built from Model Boat plans. I am sure that it is inaccurate but she sails well and is quite manoevreable (not sure I have the spelling right! I checked against a spell checker and nonredeemable was the nearest!) with 2 props and rudders.
It is just 34 inches loa (860 mms). Very stable though!
I used to do the calculations using a computer in the late 1960's more in the form of printed look up tables but most useful. I was more towards prismatic co-efficients useful for yachts etc.
regards Roy
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Prompted by the posts by Roy and Andy concerning metacentric height, I realised that I can quite easily use the CAD software to calculate the centre of buoyancy in the vertical direction - is that what you were thinking of when you first raised the topic Andy? I've attached a picture showing the result of this calculation for section 10 which is approx mid-ship, although I guess I would need to repeat this for all the sections and average them together in some way. It is about 1 inch below the water line, but it seems to me that this would only be really useful if I knew the centre of gravity - which I have no way of predicting.
I do not know the metacentric height of the M or R-class ships, but apparently the stability range of the M-class destroyers was 86 degrees deep loading and 76 degrees light. The period of roll from one extreme to the opposite was just 2-3 seconds! (I guess that is one aspect of why destroyer crew were paid hard lying).
Apparently these were very stable ships because, at that time, the machinery was heavy and armament light. As for superstructure, they basically didn't have much at all. The bridge was the main structure - see photo which shows an R-class bridge. This was larger than the M-class bridge, but still very light - it needed a splinter matress to give some degree of protection. Apparently this all changed by WW2 when machinery was lighter, armaments heavier and superstructure greatly increased, so the range of stability had become smaller (70 - 61 degrees) and roll times were 8-9 seconds.
Regards Mike
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I'd be requesting an immediate transfer to a land job if I was on a destroyer rolling to near-horizontal.
(http://www.thefreckledfish.com/beingsick.gif)
Andy
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Think that this 86° was all inclusive left to right - not all one sided i.e. to port - you would have to now call that the Concordia effect at 86° - what - too soon
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My feeling about this thread are that the OP is over-thinking the problem.
Total finished weight - approximately known
finished dimensions - known
weight of equipment - not known
weight/materials of hull - unknown
weight/materials of superstructure - unknown
weight/material of fittings - unknown
Surely trying to calculate centres of buoyancy, centre of gravity, roll centres and anything else is pointless?
I would have thought that this project is at the stage of 'just build it and see'.
If it's built big enough to have loads of buoyancy, then lead ballast very low in the hull will fix any of the problems of rolling, waterline, stability etc.
If it is built small scale, then the unknowns can become an insurmountable problem!
.
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Hi Plastic
I agree entirely with your general point and accept that it may not be very useful with regard to getting a model built.
But I'd like to explain that I always assumed that Andy had his tongue in cheek when he prompted me about calculating centre of buoyancy. Also, I may be a bit sad O0 but I have enjoyed going through the motions of analysing stability etc. since, for me, it has been a very effective learning exercise about ship stability in general, about features of the R-class destroyers in particular and about what I can achieve in this regard with SolidEdge 2D. Also, it gives a useful feel for the weight and positioning of the machinery etc that I plan to design and make. One other thing, since I enjoy doing this sort of stuff, I will find it interesting to use the CAD software, to estimate the weights of hull and superstructure (from surface area, thickness and density of materials to be used) and I certainly plan to weigh the components of the steam machinery as I build it - to keep it within the total displacement, if nothing else.
Regards Mike
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Think that this 86° was all inclusive left to right - not all one sided i.e. to port - you would have to now call that the Concordia effect at 86° - what - too soon
Yes, Warspite, you are correct. I double checked in the book "British Destroyers" by E.J. March and it definitely says this value is the stabilty range. Also, of course, this does not mean the ships often (ever) rolled that far, but this was the range, that if exceeded would result in a capsize. So, as I understand things, a range of 86 degrees means the ship could tilt so the decks (if flat rather than curved) would tip to 43 degrees from horizontal and still return to an even keel.
Regards MIke
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I always assumed that Andy had his tongue in cheek when he prompted me about calculating centre of buoyancy...
Not at all.
The thing is, I've always heard that destroyer hulls are "difficult": long, narrow, not much righting moment. So I think it is a worthwhile endeavour to do at least some calculations before you cut any wood. After all, what's the point of a beautiful, scale, steam-powered model destroyer if it's unstable once built, and best sat on a shelf?
Better save yourself the effort of building (or realise some tweaking's required) before you even start, I think.
Andy
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I still think you're worrying too much - after all, you're not going to be sailing the North Atlantic in a hurricane - it's probably only going to sail on a mill-pond smooth lake. :-)
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Isn't it all a bit of a compromise anyway, whatever the intentions?
If you're dealing with steam as the main motive power, in model form each of the main items, boiler, gas tank, engine etc. is a 'big lump' rather than a series of smaller items which could be distributed to a greater extent in the full size vessel. Rarely did the real ship have a single boiler, for example. Capital ships could have 20.
Isn't it more a case of the usual rules of keeping the weight down as low as poss and the stuff in the right places that it floats level, especially if you don't have much spare displacement to adjust with ballast?
I reckon you'll have more fun sorting out the speed and the steering :-))
Great project and good luck,
Tony
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Isn't it all a bit of a compromise anyway, whatever the intentions?
If you're dealing with steam as the main motive power, in model form each of the main items, boiler, gas tank, engine etc. is a 'big lump' rather than a series of smaller items which could be distributed to a greater extent in the full size vessel. Rarely did the real ship have a single boiler, for example. Capital ships could have 20.
Isn't it more a case of the usual rules of keeping the weight down as low as poss and the stuff in the right places that it floats level, especially if you don't have much spare displacement to adjust with ballast?
I can't disagree with any of that Tony, but doing the calculations has certainly made me think about these aspects more seriously. With regard to boilers, the R-class destroyers had 3 one behind another. I plan to use one monotube boiler - long and low which will pretty much resemble the overall shape of the three separate units and, like them, will be just forward of midship. Also, regarding fuel, the actual ships had fuel oil in war tanks in the very bottom of the hull beneath the holds. (Also peace tanks higher up on each side). I have always planned to use an electrically-pumped parafin burner (a lighter version of the one I described in another thread: http://www.modelboatmayhem.co.uk/forum/index.php/topic,47453.0.html (http://www.modelboatmayhem.co.uk/forum/index.php/topic,47453.0.html)). Thinking about buoyancy etc makes me realise I should position my fuel tanks in the same places as the war tanks in the prototype - this hopefully being one of the several advantages of using paraffin. The engine will (in theory) be in a similar location as in the prototype - just aft of midship.
I cannot contribute usefully to the debate about how useful buoyancy analysis might be since I have absolutely no experience of building model boats. Also it is clear that one can locate the items I mentioned above without undertaking detailed calculations of centre of gravity etc. But, I find this all interesting stuff and I hope to attempt more of the analyses just out of curiosity - especially since I am further encouraged, knowing that Andy's tongue was not in his cheek after all. ok2
Regards Mike
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You may be interested to know that all the real ships were subjected to a incline stability test when new and after refits when alterations etc are made, so even with real ships there is a belt and braces attitude. By the way the principle of the longitudinal stability and trim is BMl = I to power of 2 over 12d, where Ml is is the longitudinal metacentre of a ship, I = length of ship and d is her draft.
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You may be interested to know that all the real ships were subjected to a incline stability test when new and after refits when alterations etc are made, so even with real ships there is a belt and braces attitude. By the way the principle of the longitudinal stability and trim is BMl = I to power of 2 over 12d, where Ml is is the longitudinal metacentre of a ship, I = length of ship and d is her draft.
Thanks Dodes, I did not know any of that – or about merchant ship displacements that you mentioned previously.
It is certainly interesting and, prompted by your post I Iooked up about incline testing. I was picturing a ship being tipped until it almost capsized, but gather instead that, according to current International Maritime Organsation rules, it involves moving calibrated weights across the ship to create inclinations of just 2 to 4 degrees which are accurately measured to enable calculation of the location of its centre of gravity. Is that right and, if so, do you know if the admiralty requires (or at least did require in 1916) similar tests?
Hmmm, I shall have to make a more determined effort though, if I am going to understand about BM1.
Regards Mike
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I know that all the major vessels between the wars where inclined and most probably the ww1 vessels, ref centre of buoyancy that is where the force of buoyancy acts upwards and depends on the underwater form of the vessel and is the same for transverse and fore and aft metacentric height calculations etc.
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Hi Mike.
I am in the process of building a 1:96th scale model of HMS Ready (qv) and i chose this one beacause her albeit a bit dark and small photo in janes 1919 shows her to have a ram bow. Have you come across any suggestions in your readings that any of the class were initially built with ram bows? Ready was a Thorneycroft boat and assume she was originally built as such before having the bow rebuilt as a clipper bow (Am I using the correct term?)
Regards your concerns over only creating white smoke, could you spray some parafin into the boiler at the top to carbonise and create some black smoke like tanks and real life ships did to create screens??
Good luck with your build.
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Hi Ballastanksian
Thanks for the suggestion about making smoke - that is definitely something I shall keep at back of my mind for when I eventually have a model ship nearing completion.
I've had a look though the books I have and cannot find any mention of a ram bow on HMS Ready or any other M-class boat. I have made copies of parts of the book "British Destroyers" by E. March. He summarises the Emergency war programme M-class boats as follows: "In all, 79 destroyers were built to Admiralty design, 7 to Yarrow and 4 to Thorneycroft designs. In certain boats the length was increased by 3 to 4 inches, and the beam by up to 2 inches, some of the later boats had an L.O.A. of 275 ft 10 in. Many did not have geared cruising turbines ......." I would have thought that if any ship was designed with a ram bow it would have been mentioned here, but I suppose that lack of any mention does not rule it out. In the book on British destroyers by Manning there is again no mention of ram bows but there is a good largish photo of Ready with a clear view of the bow. Also, March's book has a good photo of HMS Patrician - another Thoneycroft special built in the same order as Ready. Please let me know if you'd like a copy of either/both of these and I'll scan them and send it (direct to you rather than posting it on this thread because of copyright).
Sorry not to have any positive info on this, regards
Mike
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Thanks Mike. I would like to see these so I can see if they match the postage stamp sized image I have! Sods law says that there was a dreadnaught or armoured cruiser parked just behind her when the image was taken with the ram bow protruding at just the right point to make it look like it belonged to the Ready!
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In terms of actual model stability for a ship of this type, I have a Deans 1/96 HMS Amazon (1906), 900mm long.
As you can see from this movie clip despite being only 89mm beam she is a good sea boat with little roll even on tight turns.
https://www.youtube.com/watch?v=7Cl_HNu06WY (https://www.youtube.com/watch?v=7Cl_HNu06WY)
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Thanks Mike. I would like to see these so I can see if they match the postage stamp sized image I have! Sods law says that there was a dreadnaught or armoured cruiser parked just behind her when the image was taken with the ram bow protruding at just the right point to make it look like it belonged to the Ready!
I've just sent you a PM
Mike
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In terms of actual model stability for a ship of this type, I have a Deans 1/96 HMS Amazon (1906), 900mm long.
As you can see from this movie clip despite being only 89mm beam she is a good sea boat with little roll even on tight turns.
https://www.youtube.com/watch?v=7Cl_HNu06WY (https://www.youtube.com/watch?v=7Cl_HNu06WY)
Hi Bob K
Thanks for that link. I very much like your boat and it is interesting to see a model of these destroyers in motion. It is certainly reassuring to see that is so stable - I was fearing these pencil shaped and shallow draft boats would be a bit delicate. I'd be very interested to know what motors you used in it. Also, did you need much ballast? If so, where abouts is it placed - I read in other posts that placing the ballast up the sides of a hull has a different effect to placing it in the bottom, so I'm wondering how this might affect these destroyers.
Regards Mike
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Thanks Mike. You said yours was to be a larger scale for a steam engine. I have seen a steam powered early TBD on Mayhem so know it can be done.
My 1/96 is powered by two tiny Raboesch motors of slot car type. An action P94 twin ESC with mixer, and a 3700 mAh NiMh is also the ballast under the second funnel. Always fit ballast as low as possible. These ships were fitted with bilge keels, which helps the models stability.
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I found the Mayhem thread on HMS Velox of 1904. 1/64 scale with Puffin steam engine. This should give you loads of tips.
http://www.modelboatmayhem.co.uk/forum/index.php/topic,42434.msg449137.html#msg449137 (http://www.modelboatmayhem.co.uk/forum/index.php/topic,42434.msg449137.html#msg449137)
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Thanks a lot for that link Bob and for the replies to my questions. Following your previous post I was going to look for the thread on the steam TBD, but now you've saved me the bother. Another very nice model early destroyer.
Regards Mike