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[derekwarner]

Here it is....from 2105.......well worth re-reading Bob

http://www.modelboatmayhem.co.uk/forum/index.php/topic,50193.0.html


Derek

[Geoff]

I believe it was more a question of the mountings. Victorian Battleships had different mountings "Vasseure" or something like that meant when the gun fires it moved backwards up a slope so it was possible to pull the guns back even further for maintenance. I believe the subsequent pedestal mount became the standard as it was much lighter and more flexible in train. The 6" guns would have been very similar to Iron Duke so would not have been able to be pulled back into the hull.

Rubber may be okay or perhaps metal in a spring so if hit they can bend?

Cheers

Geoff

[Colin Bishop]

Yes, that makes sense Geoff. Am I right in saying that the pedestal mount came in with the QF version of the 6 inch gun?

Colin

[Geoff]

Correct! Also foxed ammunition sped up the rate of fire.

Cheers

Geoff

[Bob K]

You guys are a super mine of information and constructive suggestions.  Many thanks.
I remember that thread, I believe whilst Nick was building HMS Prince George.

HMS Agincourt was fitted with eighteen BL 6-inch Mk XIII 50-calibre guns, which equates to a barrel length of 25 feet -  very long.  Rate of fire was about five to seven rounds per minute, which implies QF and therefore pedestal mounted.  As I can find no photos of her with guns retracted I am going to assume they were fixed, and provide semi-circular barrel apertures in the hatch doors.

Colin:  Now that is a really neat alternative to providing protection to the overhanging detail parts.  Underwater piano wire fenders, easily fitted just before launch, and readily replaced if they get bent.  I like it 

[bfgstew]

My two pennies worth.....


Maybe have the barrels in 2 sections, threaded, mount small stepper motor so outer portion of barrel can retract/extend. As I say just a thought.


This by the way is a really wonderful build and look forward to further installments........


Stewart

[Geoff]

I'm not convinced underwater piano wire fenders would be effective, not least of which the possibility of damage to other models but more likely they could be punched through the side. The guns on ID turn so that in the event of a collision they will rotate thus ameliorating the impact and in a way acting as fenders.

Besides, rather like the Titanic your never going to get the damage you design for!

Cheers

Geoff

[steve pickstock]

By way of suggestion re the secondary guns, I suggest that any form of rubber would be the wrong way to go. They'd take the punishment but after a while they'd start to sag, even with a metal core. Would a white metal barrel not be a better idea, perhaps even with a metal core. White metal will bend, but can be re-shaped, and more importantly won't sag, plus if you make or cast enough they can be replaced easily if the get damaged too much.

[Bob K]

Unfortunately these guns overhang so massively that I am guaranteed to break several each time I move it, let alone sail it.  Eighteen of them.  Nature of the beast.

Casemate Rework

Bit the bullet.  Opened up the top of the casemate openings by 5mm, to match the deck-step gun openings.  Thank goodness for Dremel “diamond dust” cutting disks, slicing through the hull plus rough dressing the top edges.  Now to make up some 5mm tall filler panels from styrene to adjust the bottom edges upwards.  Quite a bit of fiddly work with white filler and filing smooth afterwards.  Made-up some 5mm & 10mm wide sanding blocks with wood, grit paper and impact adhesive, 
That looks better, even if it meant one step back to make two forwards. 

Next the casemate doors.  Unfurling the 8 foot plans, each casemate had three doors, two outer ones folding outwards plus a centre one folding down.  Cut-outs for gun barrel split between the centre and one outer door.  The secondary armament did protrude, with the position of the door cut-outs dictating the “secured” gun positions at sea.  I am doing mine as cleared for action, so with doors folded outwards.  Just to make it interesting most of the gun positions have doors of different lengths.

Cut strips the width of the apertures, same height, then sectioning the doors as per plans with the cut-outs for the gun barrels.  Add the hinge plates and pins, and Ciano onto the hull face. 

Yes, I did take the gun positions into account when determining the hull split point and positions of bulkheads.  Advance planning required at each stage.



Next will be inner sub decks to mount the cylindrical outer faces of the guns, with their angled facing plates.  I will use slot car rubber tyres for mounting the gun barrels in, 18 dia x 10, exact size.  A bit of improvisation.

It was handy that I happened to have 180 brass etched porthole eyebrows in 1/96, and need 176 of them for this ship.  When I have done that I will start on the torpedo net booms.  That should be fun.    Now I am getting to do some detailing I am a happy bunny. 

[Colin Bishop]

I have not tried piano wire fenders but I don't see why they shouldn't work. They would only protrude an inch or two from the side of the boat to clear any above deck protrusions so should not be a danger to other models, in fact they should fend them off. The locating sockets could be brass tube let into the side of the model and blocked off at the inboard end. The tubes would be supported internally to absorb any shock loads. The natural springiness of the piano wire would assist in absorbing any impacts.

Basically you would just take a length of piano wire, bend 90 degrees angle in each end and spring them into the reinforced sockets. The naturalspringiness of the wire would help in  absorbing any collision shocks.

Colin

[Bob K]

I am still considering ways of protecting overhanging side detail, but thin wire "U" side fenders sounds a good option.

A set of seven fibreglass turrets are on their way from Dean’s Marine.  When barrels fitted barrel each one is half the length of my HMS Royal Marine.

More Casemate Work

HMS Agincourt is best known as having the greatest number of main armament guns ever mounted on a warship.  Fourteen BL 12-inch MK XII in seven twin turrets.  I am currently finding that her secondary armament of twenty single BL 6-inch Mk XII, 14 in casemates, was equally impressive. I have been constructing three casemate door sets for each, three doors apiece, with their twin hinge plates and hinges.  That is 84 sets of hinge detail parts.  She also carried ten 3-inch guns.

These fourteen sets of doors kept me amused for several days.  Yes, the centre doors have one hinge angled due to cut-out position.



The soft rubber slot car racing tyres have arrived so I can start work on the gun mountings with their angled casemate facings. 

[raflaunches]

Some nice work going on- I know that you were itching to start the interesting details!


You certainly won’t regret using the turrets- I’ve got some early versions (well in design!) on my Invincible that they look really good on the barbettes.

[Bob K]

Thank you Nick 

The set of seven fibreglass turrets from Dean’s Marine have arrived.  Really nice set of fibreglass castings.  Temporary use of roll of tape to show effect.



Overhanging detail problem

Just to demonstrate the potential problems of vulnerable detail projecting outside the hull, below is a photo of Black Park lakeside showing the navigation hazards when coming alongside with a much larger boat than shown.  Wooden posts, before you even get to the rough concrete edges. 

  Naff mobile phone image, I left my Fujifilm SD card at home!

With the forward facing secondary armament trained as far inboard as they will go it still leaves a vulnerable 30mm protrusion zone along a third of the hull.  Whatever you do, with 29Kg behind it, that is going to break off anything vulnerable.

The following details from the plans shows the extent of the problem





Even with guns at maximum inboard rotation there is extensive overhanging detail for a considerable portion of the hull length.  By the time I add torpedo booms and nets, plus the Admirals walk at the stern I am contemplating various methods of damage limitation.

[1] Casting gun barrels in rubber,  [2] Mounting barrels in neoprene blocks,  [3] Using telescopic sprung sections of brass tubes,  [4]  Piano wire "U" fenders.

I will have to don the Bagpuss Hat.   

[Colin Bishop]

I just rather doubt if rubber would look right, and if the guns do bend then it just leaves the other overhanging stuff vulnerable. If you spring load the gun barrels it won't protect them against anything other than head on impact. It will still be possible to wrench them all off if you 'curb' the model. 

That was my thinking when I suggested piano wire underwater fenders. Get the shape right, maybe a bow curve with right angle ends to fit into the sockets and they should deal with glancing blows as well as 90 degree impacts. Being springy they will absorb a lot of any impact. The sockets in the hull can be brass tube, securely mounted and reinforced within the hull and all that will appear on the outside is an apparent discharge pipe.

Colin

[Geoff]

I think underwater fenders would still be problematical as:

1) Even if "U" shaped they would need to project about 2" from the side to protect the barrels which means they would catch on things.

2) If underwater they would catch every piece of weed, leaf, stick etc which would give considerable drag and be unsightly.

3) With the flare at the bow on most ships they still wouldn't avoid collision damage to any great degree


Cheers

Geoff

[Bob K]

I am sure most of us have encountered damage during transport and sailing, but I believe this ship takes the biscuit in terms of the likelihood of regular damage potential. 

Colin:  The more I think on it the more I believe you right.  The shaped spring wire fenders could be fitted lakeside.  Getting the right balance of protective springiness and bendability for forming could be key.  It only needs to absorb and slow contact, rather than be an almost solid ‘crash barrier’.   The other issue is transport, with three doors to negotiate between workshop and car, plus transport itself.  I am designing a new two-deck platform for my boat trolley which also needs consideration for vulnerable protrusions.

I am assuming that the real ship would mostly have anchored offshore, of if it came alongside the secondary armament would have been above the level of the quayside.

Geoff:  The foremost item of vulnerability is 700mm from the bow, so the fender could start just ahead of this with a 30 degree angle from the hull, and about a cm below waterline.  I had even considered a 30mm thick shaped block of Neoprene each side, but this would be difficult to mount.

Other point of vulnerability most of us have encountered is very tall mast structures.  Luckily Ron K’s prototype has an excellent solution.  The roofs of the fighting tops cleverly hinge back for transport, with a natty system of folding the rigging with it.  That keeps the overall height under 500mm for transporting. 

[C-3PO]

Bob,

Could you deploy stand-off arms (via servo) or telescoping poles?

https://www.youtube.com/watch?v=KK_ebAdOiRw

C-3PO

[JimG]

Take a set of floating dock sides with the tops below the guns. Attach to the side of the pond before sailing, now you can come alongside safely.
Jim

[Colin Bishop]

Geoff, I'm not sure you have understood my suggestion, my fault probably. The idea is to have a single horizontal length of wire on each side that curves smoothly out from the the hull, a bit like the upper edge of an underwater bulge but far enough out from the hull along the midships to protect the guns etc. The ends would be bent over and plug into sockets fore and aft. Some experimentation would be needed with the gauge as it would have to be strong enough to 'bounce' the hull off a glancing alongside contact with pondsides or other models without losing too much flexibility.

Obviously this would only protect the major part of the sides of the ship. Something else would be needed to protect the stem from a head on impact but again a sprung wire shape could perhaps be devised.

Colin

[C-3PO]

Take a set of floating dock sides with the tops below the guns. Attach to the side of the pond before sailing, now you can come alongside safely.
Jim

This would seem a very simple solution - perhaps 22mm pipe insulation with a broom stick in the centre to give it weight and stop it flapping about in the wind, or weighted 22mm plastic pipe in a frame covered in insulation to give it bulk- somehow attached to side of pond - floating in the water below the guns. Perhaps it might need to be doubled using 2 strips with cable ties to make adequate stand-off ...Could even be chopped up into 12-18" lengths attached to each other with a ring at each end to aid transport



C-3PO

[Colin Bishop]

Two separate issues here I think. One is launch and recovery when the model should be under control and the handler has a way of buffering the model from the bankside as per the previoys post. The other is how to deal with situations where the model might not be under control ir where it is sideswiped by another boat, not an uncommon occurrence during free sailing sessions unfortunately. I think the model is more likely to be damaged when out on the pond than when being launched or recovered although that does not mean that care needs to be taken when doing so.

Colin

[C-3PO]

Good point Colin - maybe I should have read the whole post...

A fascinating dilemma. Could the gun mounts or what the mounts are mounted on (assuming accessible to replace) be made sacrificial perhaps from very thin wood (balsa)or a brittle material. Even with the most sophisticated protection system I guess the worst culprit as Bob hinted at will be a human manoeuvring the model from A to B or in/out of the car. Like most modellers I have a box of "bits" that have been knocked off my boats- the most frustrating element is the more careful I try to be I always seem to catch something - indeed it seems sometimes that I only have to look at at model and off pops another part...

C-3PO

[Colin Bishop]

I think you've just described the third situation there C-3PO. An invisible force field is clearly needed to protect the model while in transit. Must be a suitable Arduino circuit out there somewhere. 

Colin

[Bob K]

Incredible ingenuity chaps.  Not sure how much is practical though.  A telescopic fender boom would need directing, and a floating quayside boom would be a lot to transport and rig up lakeside.  As C-3PO said “it seems sometimes that I only have to look at a model and off pops another part...”.  I have that T Shirt !
An Arduino powered force field - Now that's an idea 

Transporting the monster

Speaking of transporting, I am currently working on adapting my Silver Cross push chair trolley to carry both 2.1m hull halves, double-decker style.  Two 900mm x 400mm platforms in 10mm ply.  The bottom one recessed for the trolley handle pivots platform, with wood battens to locate in the frame, as per the original.  I found some nice wardrobe rails with three hole mounting flanges.  Four half metre 20mm diameter tubes locate in these to assemble the top deck on in the car park.  Very little extra stuff to carry, the two flat decks snuggle into my small boot along with the folded trolley. 

The deck tops will be surfaced with thin bathroom carpet, both as cushioning and anti-slip. 
Effectively just a two level version of my existing trolley top, but a bit longer.



I have cut the plywood, just needs fitting the frame guide battens; carpet; tube mounts; and plastic “U” channel edging.  Give me a couple of days and will have photos  of the finished ship carrier.

Even getting it to the lake edge intact would be a major achievement 

[Geoff]

Bob,

Just make sure its not top heavy as a hollow or bump on the ground could cause a disaster!

With ID I made an "A" frame with two wheels at the base and a carry handle at the apex. The concepts being the base gives stability and my arm provides some suspension. Now my "A" frame isn't long enough to support ID so I made some extension arms which go under/over the horizontal bar of the "A" so it locks into place. This then gives me a long trolley to pull and importantly because it breaks into two parts readily fits in the car.


Cheers

Geoff