HMS Victory by dafi - Heller - PLASTIC - To Victory and beyond ...

[trippwj]

Beautiful work, Dr. Dafi! 

 

Looking through several references on naval ordnance, I could not come across any that showed a second preventer breech rope.  Not sure where Goodwin got it from, but what the heck!  A quick look in Goodwin at the section on ringbolts etc for guns references the Shipbuilders Repository of 1789.

 

There is a great contemporary French drawing available via Wikipedia (i know, not the best of authoritative sources) - see http://en.wikipedia.org/wiki/File:Antoine_Morel-Fatio_pl10.jpg%C2'>

 

I also looked through Captain H. Garbett, RN, Naval Gunnery from 1897.  He has some great illustrations of late 19th century and older naval ordnance, but the only one of the carriage was again sans a second breeching rope.

[dafi]

Thank you very much Wayne,

 

was there meant to be a link for the Wikipedia? Would like to see the picture :-)

 

Need to have second look at the SRo1789, too.

 

XXXDAn

[trippwj]

Very strange...I could have sworn I posted a link there!   Durned Captain tentacle got ahold of it?

 

http://en.wikipedia.org/wiki/File:Antoine_Morel-Fatio_pl10.jpg

 

 

[rybakov]

Hello Dafi

 

According to John Masefield's "Sea life in Nelsons time"  the breech ropes were doubled for a general fleet engagement, as the recoil

would get more violent as the guns heated being continuouly fired.

 

I wonder what you'll find next to amaze us

[dafi]

Thank you rybakov,

 

that is a good hint! Need to have a look. 

 

But this leaves me to the other question of mine: Why do hot guns jump and recoil that violently?

 

http://modelshipworld.com/index.php?/topic/3963-whay-do-hot-guns-jump-violently/#entry112437

 

Cheers Daniel

Edited October 17, 2013 by dafi

[rybakov]

Hi Daniel

 

Two possible explanations:

 

Powder burning produces gases and heat. It's that heat that makes the gases expand and increases pressure within

the barrel eventually expeling the ball.

the metal of the barrel absorbs some of that heat. As it gets warmer and warmer less and less heat it absorbs leaving more

to expand the gases leading to increased pressure higher muzzle velocity and higher recoil.

 

That's one

 

Another would be that as the gun heats the outside diameter increases and the inner diameter decreases as the muzzle wall

expands and you have a tighter fit with less pressure loss.

 

 

But sincerely....... I really don't know

 

 

All the best

Zeh

[amateur]

The last one is not correct: when an iron ring increases temperature, both the inside as well as the outside diameter increases.

Is a nice experiment at highschool: copper sfere with a diameter slightly below the inner diameter of an copper ring. Sfere won't go through Heat the ring, and the sfere will fall through.

 

My guess is a more violent explosion as the powder heats.

 

Jan

[Stockholm tar]

Daniel,

 

I also like your 'kebab' stick idea, to get the pricker and then the drill into tight spaces. I'll have to try that.

 

I'm also enjoying the 'drama' of your Victory build.

 

Incidentally, in his 'HMS Victory, Owner's Workshop Manual', Goodwin says that all 24 and 32 pdr guns were rigged with breeching and preventer ropes, due to their heavy recoil. Also that with a standard charge and rope restraints this could be up to 11'.

Edited October 18, 2013 by Stockholm tar

[popeye the sailor]

cool!.......a spinal tap moment     I can see having the extra breech rope......the bigger guns would probably rip the eye bolts right out of the wall!

[rybakov]

Hi Jan

 

I reckon I should have remembered that

 

Zeh

[themadchemist]

Well I just made it through your complete log for the first time finally. Seems I keep getting part way through and losing my place...

I must say... What an Amazing and Facinating idea exchange and I love your trial by fire methodology Dr dafi.

 

On the guns... I have no clue.... but..... the guns would heat from within the barrel, toward the outer surface. Heat energy always transfers from hot to cold. The powder end would also heat faster then the barrel end as it would be more exposed to the reaction and for a longer time. I visualize the barrel bore becoming teardrop shaped as it heated, at least within the expansion rate of the cannons material at a given temp.

 

Thermally conductive substances such as metals usually transfer heat efficiently, unlike ...say... glass. Thats why a quick change in glass temp on one side causes breakage. The barrel overall, to my thinking at least, would expand radially from the center and more at the flint end.

 

In rocket fuel trials early on. there were early problems in uneven burn causing the launch to be throw off its center of mass causing wobble, which usually lead to mishaps (ie big BOOMS). On a cannon, the walls attempt to prevent this wobble, but as clearances expand the wobble would cause the recoil to be less symmetrical or straight back. A small shift of momentum to the left or right could increase the force on a single sides breeching rope, possibly to its breaking strength, hence a second rope picked up the slack. 

Symmetry of burn would also be critical. In an internal combustion engine the spark plug placement is key to maximizing efficency in torque and HP. Thats why Fords Boss 429 had a semi-hemispherical head and Mopars had a full Hemispherical head design. This forced the redesign of the plug placement in the valve cover center, but creates a more centered push on the piston top. In comparison the cannon has two issues... the flint fires on top (center of the back would be optimal) and the compression surface (ball) is not flat. If the burn reaches the top of the ball before the bottom, I can see a cannon recoiling with a downward thrust as the unsymmetrical burn would cause the ball to spin which could cause lift at the back wheels. Combined that with any side to side action and I'd want a preventer rope. To avoid these issues engines are build to be at tolerance when at temp, but this wouldn't work with cannon as the clearance would be to close on cold fightings.

 

Something I did notice, previously you had one of the breeching ropes wrapped araound the lower back of carraige, but not so in the most recent modification (I think the rings make sense, as some slack helps absorb recoil). That carriage wrap, to me, seems important as it would help force a more symetrical recoil

 

Of course this is all hypothesis and I could be completely mad.

 

Oh and in the entranceway doors. You forgot Pocket doors as an option   or possibly DeLorean-esk gull-wing doors.....

[dafi]

Thank you all for your input! Very appreciated :-)

 

Next cleared up the breeching ropes on both sides ...

 

 

... especially the loop ...

 

 

... and also looked at both sides that the ropes won´t be stuck underneath the wheels.

 

 

Then checked the length ...

 

 

... and Jan was right, here comes Captain Hook ...

 

 

... and have him installed in all his glory.

 

 

 

 

XXXDAn

Edited October 20, 2013 by dafi

[Erik Nyren]

The fly looks a bit out of scale but other than that amazing detail and precision.

 

Simply beautiful

 

Erik

[mtaylor]

Is that beast dead or merely sleeping?   Oh... it's flynot a parrot.  Nevermind. 

 

Good to read that you've solved the preventer rope mystery. 

 

At first I thought the "hot guns jumping and recoiling" was a bit of literary license on part of some authors.  But then, I remembered seeing some videos of American Civil War (aka, The Recent Unpleasantness) where the gunners were firing for effect (load as fast as they could).  I believe it was a competition to get 10 rounds off, points for speed and accuracy.  Last several shots made those cannon jump also. 

[dafi]

Mark, Eric and all the others: Thank you tons for your feedback.

 

For the hot guns to jump violently, I copied the answers into a new thread for not getting lost here.

http://modelshipworld.com/index.php?/topic/3963-whey-do-hot-guns-jump-violently/?p=112437

 

Have a great time, Daniel

[popeye the sailor]

it might be the dead parrot........kipp'in on his back,  after a prolonged squawk  :D ............ lovely pumage!

 

sweet detail Daniel

Edited October 21, 2013 by popeye the sailor

[NAZGÛL]

Love the approach! Very realistic and it's hard to tell the small scale. Great weathering!

 

/Matti

[dafi]

Thank you Sirs!

 

And next Dr Tentakels wild cousins went too into the trap :-)

 

 

But then dafi got trapped himself ...

 

... to much flue - too much nice substances - and forgot on the left hand gun to lead the breeching rope through the big guidance rings on the side of the carriage ...

 

... where both red squares are , gun well glued, breeching ropes well fixed on the hull ...

 

... okokokokok, hard way, means taking the guidance ring out, opening it, putting around the breeching rope, refixing in the eyebolt and reclosing the ring ...

 

... everything in there, deep-deep-down inside the bowels of the Vic ...

 

... tight, dark, but luckily not steamy ...

 

... and somehow managed to fix and even the picture looks ok :-)

 

XXXDAn

Edited October 29, 2013 by dafi

[amateur]

When the gun recoils (jumping or not ), do both breachropes have the same amount of slack,

or is the thinner breachrope slightly longer, and just the safe guard if the thick one fails?

 

Jan

[dafi]

I made them both for the same length, respecting some a tad shorter if fixed on the hanging knee :-)

 

The given dimension is three times the length of the barrel, and this really is just about the right length as I could see on the model. Both have the same diameter.

 

The positioning of the ring on the side is very clever, as it keeps the rope clear of the hind wheels. But even with both ropes I managed to find an arrangement, where both ropes can be kept clear of each other and the wheels, as looping around the back of the truck or fouling the wheels would have had very unwanted effects ...

 

XXXDAn

Edited October 29, 2013 by dafi

[popeye the sailor]

still some impressive work Daniel.........I didn't notice it

[dafi]

Hy Popeye and Lawrence, thank you!

 

@canoe21

I just use the template to sign the position with a pen and then remove it. Otherwise the danger of glue getting stuck under the template is too big.

 

http://www.dafinismus.de/bilder/Etch_Victory_en_5_v10.pdf

Page 13

 

Cheers, Daniel

Edited November 1, 2013 by dafi

[dafi]

My pleasure to help !

 

XXXDAn

[popeye the sailor]

tips for the Victory.......but can be applied to other builds as well.   very nice 

[dafi]

Thank you Popeye,

 

it turned out, that the instructions for my parts became some kind of "best-of" of the tips from this building report here :-)

 

Here the collection:

http://www.dafinismus.de/bilder/Etch_Victory_en_1_v10.pdf

http://www.dafinismus.de/bilder/Etch_Victory_en_2_v10.pdf

http://www.dafinismus.de/bilder/Etch_Victory_en_3_v10.pdf

http://www.dafinismus.de/bilder/Etch_Victory_en_4_v10b.pdf

http://www.dafinismus.de/bilder/Etch_Victory_en_5_v10.pdf

http://www.dafinismus.de/bilder/Etch_Victory_en_6_v10.pdf

http://www.dafinismus.de/bilder/Etch_Victory_en_7_v10.pdf

http://www.dafinismus.de/bilder/Etch_Victory_en_8_v10.pdf

 

Cheers, Daniel

Edited November 1, 2013 by dafi

[dafi]

This week was week to remember, because of ...

 

*please fill in your own guesses*

 

XXXDAn

[popeye the sailor]

personal:  anniversary?

 

modeling:  all your cannons are rigged 

[dafi]

modeling: all your cannons are rigged

How do do. you know me that well ?

 

Quite close - all guns finally fixed on the lower deck :-)

 

Dan

Edited November 1, 2013 by dafi

[gil middleton]

Daniel, After a long hiatus, I still marvel at your intricate details. And just when I think I've solved a conundrum, you challenge us with more questions and insights.  Great fun to follow your log. Cheers, Gil 

[dafi]

Thank you Gil :-)

 

And some tinkering was done too ... 

 

First replaced the parcel strings aka side tackles by a better suited rope and reworked the pullies to get them into the right dimensions now.

 

 

Preassembled outside the hull and a small thread around for not getting tangled up and in we go. For the back hooks I use fine electro pliers, they give more control than tweezers ...

 

 

... but for the front hook no other way than the tweezers for space reasons.

 

 

In the end everything ended on the right place aka hook ...

 

 

... and time to pull the strings :-)

 

 

And now usually come the nice coils on the deck, but like the drawing looks already a bit naughty, I wanted to look for a spiritual salvation for those sailors not to get into ideas ...

Often seen too that the rope leads in a straight line from the pulley down to the coil. 

 

 

 

This made me think ...

 

First: How can a rope be pulled straight down to the coil? The coil just lies on the deck and it is not fixed. The only way would be the rope to fall loosely from the pulley to the deck and is lead there to the coil.

Second and more important: Why are the tackles not stopped/belayed? It is possible to show a unsecured tackle in dry dock like the V. in P., but on a real ship, the first wave loosens the tackle and soon one has a lot of stray guns on the deck dancing samba ...

 

First consequences for my build, either one holds the tackle or it should be belayed :-)

 

For the next guns to be worked on, battle stations should be already prepared, but crew occupied on the guns of the opposite side.

 

So the tackles got secured by a half hitch (or a overhand knot with draw-loop) behind the rear blocks.

 

 

 

 

And something surprising but logical: As I used the original lengths of rope, the back tackles do not need a coil or something alike, as there is almost no rope left :-)

 

 

I letted the free end on the deck, even though it could have been arranged nicely otherwise.

 

XXXDAn