Model Boat Mayhem
Mess Deck: General Section => Model Boating => Topic started by: Edmund on January 28, 2009, 11:11:37 am
-
Hello, Anyone please tell me how to do hull plating ? would the plates lap over at the edges , like in - out - in - out? (like Titanic for eg), or would they butt up edge to edge? Looks like they have something between them horizontally on the pics . Hmm {:-{
thanks , Ed. :-))
-
Ed,
"It all depends" is the answer. There are several systems of plating depending on ship type with 'all flush' being the most expensive. I will dig out my old books and put up a few pics.
Barry M
-
Here are just a few links to some builds and some questions regarding hull plating.
http://www.modelboatmayhem.co.uk/forum/index.php?topic=14370.0
http://www.modelboatmayhem.co.uk/forum/index.php?topic=13888.0
http://www.modelboatmayhem.co.uk/forum/index.php?topic=2165.0
http://www.modelboatmayhem.co.uk/forum/index.php?topic=4715.0
If you go to the main page and do a search you will find more.
I hope this gives you a start.
-
diagrams taken from Nicholsons seamanship and nautical knowledge 1554 vintage. hope they help.
-
Eh? - 1554 vintage? You must have been an apprentice to Noah! O0
Mine are only 1942 vintage.
-
Next
-
and last
-
slip o' the finger, barrie.
must take more tonic with it, and the sun wasn't even over the yard arm either,lol {-) {-) {-) {-) :embarrassed: :embarrassed: :embarrassed: :embarrassed:
-
:-)) Thanks for the links and all the diagrams, just the job, the one re applying to plug esp , as this is what I will be doing. Right ah's off to peruse some diagrams :}
Oh trying to build something like this, so @ 1/48th probly don't matter much anyway {:-{
ta,
Ed. :-))
{-) butt straps
-
Hello again :-)
So on ere where the armour plates join , it looks like there are squares covering the butt joints? does that sound right ? They wouldn't be joggled or owt fancy like that ?
thanks, Ed.
-
Looks like an external butt strap.
Barry M
-
Oh aye it does, almost exactly like the first diagram , must ave missed that :embarrassed:
So it just claggs on top over the joint then. :}
good, thanks.
Ed.
-
Looks like an external butt strap.
Barry M
Is that some of sex toy?? {-) {-)
-
Just out of interest , how big is the head of a rivet , I suppose that is like asking how big is a screw? %%
Ed.
-
When flattened while hot, the head of a rivet is required to be 2.5 x the shank diameter without cracking at the edges.
Cheers,
Barry M
-
Heres a run at it by Pat Matthews
post #147
http://www.rcgroups.com/forums/showthread.php?t=775147&page=10
:-)
-
What I really meant was what is the actual physical dimension of the rivet head ? so if it is a 1" diam rhe head will be 2.5". Is that like a Titanic sized rivet ? Would big uns like these be used fer an Insect ? I'm trying to figure out how big they would need to be on a 1/48th scale model. :-)) Pretty small I'm guessing. {:-{
ta.
Ed.
-
Hi Ed,
As an educated guess at 1/48th scale i would suggest a dome head rivet would be about 0.50mm diam, maybe as large as 0.75mm.
Ian
-
:-)) Thanks Ian, um I better find that jeweller's eyepiece then {-) Ed.
Hmm well I make that um 1.5mm x 48 comes to 72mm <:( which is way too big. damn >:-o
-
A little more on plating,
http://www.rcgroups.com/forums/showpost.php?p=8805900&postcount=169
and rivets.
http://www.rcgroups.com/forums/showpost.php?p=8805900&postcount=169
http://www.starwoodmodels.com/products/ssm/rivetkit.php
I did rivets on a friends armor model using super thick CA glue.
It is very difficult to stay consistent.
-
Hi Ed,
I meant that the finished rivet head would be 0.50-0.75mm diam at 1/48th, i think you may have mistakenly multiplied this by 2.5 and that is why it may seem too large.
A 0.50mm dia head x 48 would give a domed rivet head of 24mm dia, this is quite small so i would suggest 0.75mm dia for heads which scaled would give you a 36mm dia rivet head. :-))
I always look at photographs with crew about the decks this is for a comparison between all fittings/fixtures to gauge, height, width and perspective this is a must when spotting sizes for such things as bolt heads and rivets, which are not allways high lighted on builders drawings.
Good luck and i hope this has cleared up the confusion?
Ian
-
Thanks fer the links there Umi :-))
Oh sorry Ian I was referring to a sewing pin which is about 1.5mm / 1/16th head size which makes it about 2 1/2" fer a 1" rivet in the real world which is way too big that would be nearer 1/24th scale ?
I will have to have a ponder whether they will be really noticeable anyway at 1/48th {:-{
thanks ,
Ed.
-
Just say it's a flush-riveted hull. %)
-
Hi Ed,
The rivets would be as prominent as the butt strap image you posted, so it is really your choice if it were me then i would show them.
Two methods of doing this are,
1, when making the plates out of litho plate emboss the back edges of them with the rivet patterns and glue into place.
2, using a fine needle syringe filled with a slow setting adhesive, either PVA or a very slow cure epoxy dab the needle tip along the pre marked lines on your plating and leave to set overnight. If you mess up these, just wipe off and have another go.
Cheers
Ian
-
Hi all
Have a look at the picture - If we look at the size of the holes that have bean drilled in the deck beam this will give us some indication of the size of rivets
this may help
John
bluebird
-
Perhaps these 2 pics will help you. 2 different sorts of plating, one on a small ship and the other on a large one. Both with revetted hulls and not a rivet head to be seen!
-
oops. try again.
-
Heres an iron hull from 1864. All riveted, longitudinal joints lapped-in and out, transverse joints butt and plate on inside
Not a rivet to be seen on outside. except at the bow piece
kiwi
-
hi there
the link below was added to the Spashett build of mine, by Dave Tait - and it shows the rear end of the fishing vessel - if you look closely you can see that there seem to be proud round-headed rivets - and this has led me to believe a new chain of thought;
were a large number of smaller vessels say, from Coasters down to say, fishing vessels - that were built from steel used round-headed rivets on the outside, for cheapness, where larger vessels may have used counter-sunk rivets dueto the fact that the owners could afford it. Think of it this way, for every hole drilled in a plate - that is flush fitted with a rivet - has to be countersunk - so this in turn will incur more expense for the labour involved. Just a thought
http://www.senseofplacesuffolk.co.uk/calm/images/Suffolk/LRO_1300_72_42_47.jpg
aye
john
-
:-))Thanks fer the pics and links folks. Very interesting.
I managed to get a copy of "Merchant Ship Construction" bt H J Pursey from 1950 which is very interesting indeed and vol 1 and 2 of "The Design & Construction of Ships" by Professor J H Biles, from 1911 and 1919 which is giving me a headache. {:-{
So I will probably use 1/64th ply for the plating %) not really a plasticard fan. :((
Ed :-))
-
edmund.
i think you might find it far easier to plate with 120 - 140 gram card from an art shop.
when moist with pva glue you would find it moulds far easier around the stern than none pliable 1/64 th ply. you can then seal it all with cellulose sanding sealer before painting.
mind you it's preference at the end of the day. :-))
-
Two schools of thought on this. I sailed on many ships with rivetted hulls (and all the upper deck structure). I really cannot recall being in any ship that had flush rivetting. All the ones I remember had (on the visual side... the outside) just slightly domed tops...the "inside" was different, there you had the "big-head" (no comments please). But that is the main reason that I make my "rivetting" almost imperceptable. Very small (and dare I say it) cheaply built thingies could well have prominent heads showing. But it all comes down to "scale" again. Cheers. BY.
-
You would find that riveted steel or iron construction armoured warships from the period that ED is asking about would have countersunk head rivets on the hull and decks
This was intended to reduce fuel consumption and fouling of the hull, except for the stiffening plates like the close up image on the external butt strap and other external fixtures added after the main hull structure had been built.
And as a general rule most superstructure plate parts were fixed with either dome head or a flattened cone head pattern rivets depending on the weight/gauge of plate.
I think using merchant ship images as a comparison to methods of Admiralty hull construction is OK, but most warships were built to different specifications and standards so they aren't really a good accurate example.
Ian
-
You would find that riveted steel or iron construction armoured warships from the period that ED is asking about would have countersunk head rivets on the hull and decks
This was intended to reduce fuel consumption and fouling of the hull, except for the stiffening plates like the close up image on the external butt strap and other external fixtures added after the main hull structure had been built.
And as a general rule most superstructure plate parts were fixed with either dome head or a flattened cone head pattern rivets depending on the weight/gauge of plate.
I think using merchant ship images as a comparison to methods of Admiralty hull construction is OK, but most warships were built to different specifications and standards so they aren't really a good accurate example.
Ian
Point taken (no pun intended) BY
-
So um the plates are joggled on the vertical joints and overlap the adjacent plate :(( summet like this :(( Do the edges always face backwards?
Ed.
-
YES :-))
-
:} good good.
Any idea what these things are please {:-{ or is it just where the plates lap :((
thanks,
Ed.
-
sorry edmund but I can't make out what I'm looking at. {:-{
-
:(( Think they mebbe rubbing strakes? Think it the same ship as in post 1 :(( They seem to coincide with the plate edges?
Ed.
-
looks like joggled plating to me...the expensive way of building a (real) ship. BY.
-
Hi Ed,
The highlighted strips are horizontal butt straps, which also double as rubbing strakes to help protect the hull plating from carless :embarrassed: driving !!
Ian
-
Thanks Ian :-))
:o So this would mean that the the plates are flush and butt jointed , rather than in out then {:-{
Ed.
-
No, they are made in a sort of "Z" shape at the edges so the seam of the upper plate fits snugly over the seam of the one under it.
-
Brian has described it spot on
These horizontal strakes you highlighted are riveted along the joint lines of two plates as external stiffeners, connecting the top of the lower plate to the bottom edges of the top plate.
If you take three sheets of A4 paper and lay two of them flat on a table spaced 6 1/2" apart, then lay the third sheet over them with an equal overlap at each side on the bottom two sheets this will give you a basic understanding of plate joggle. The vertical end strake should be positioned as if you were laying bricks with a half joint or bond, ie; staggered --------------I---------------I---------------I
-------I--------------I---------------I--------
--------------I---------------I---------------I
Cheers
Ian
-
Edmund hi there;
http://www.dockmuseum.org.uk/archive/index.asp
Have a look at this link - it is for the Dock Museum - its a good website - and there are literally thousands of photographs of ships of all ages, under construction. I did begin looking on this website for close-up photographs of warship plating for you (I know they are there) cos I have used them myself before, for my builds. Like everything else...I was side-tracked :-) so, if you have a spare couple of hours - enjoy the website cos I think its great - and happy hunting. It may answer a lot of your questions.
aye
john e
bluebird
-
:-)) Thanks fer the link and hel[ folks.
I got me 2 photos of Mantis today (finally) from the IWM, so have been looking very closely at them %%
So on the pic below A goes on top of B which in turn goes atop of C by the look of it? {:-{ and the trailing edges lap over the plate behind.
The things on the bow pic are butt straps and rubbing strakes ?
I thought joggling was the dogleg that allowed the faces to finish flush not the in out arrangement?
Right ahs off ti read about landing edges {:-{
Ed.
-
Hi Ed,
The photo showing the plating with the A,B,C legends and you understanding is spot on, the plate above the portholes is a sheer plate to reinforce the deck to hull plate edge.
If you were to continue your a,b,c down to d then d would overlap c then e would be under d etc;
What drawings are you using for the Insect class gunboat? if they are from the NMM then they will have the full shell expansion drawings aswell, a good friend of mine built Scarrab many years ago using those drawings.
Ian
-
Hello Ian,
I am using the 1/48th HMS Gnat plans from Marine Modelling/Traplet? apart from cross sections they are just drawings of profile and plan views with no plating detail apart from the line of the reinforcing sides.
Apart from that I got a couple of photos from IWM of her on launch day and then just pics off the net really, nothing very detailed but I can make out most of the side plating i think, not back or underneath though {-)
I didn't know there were any plans of any of the real vessels available.
<:( and I just took out a bank loan to pay for these two photos.
Ed.
-
Hello, quick question, {:-{ the ends of the hull plates look to be at 900 to the edges as opposed to plumb , does this sound right please?
ta, Ed. :-))
-
Hi Ed,
It was normal practice to cut them at 90 degrees, although this changed depending on the hull form and certain other areas where plates had to be bent and worked for example around the running gear, these would be cut and shaped into and around the shaft exit fairing plates.
It was far easier to work a good square 90 deg edged plate in the midship porition of the hull, and in theory this would continue as far forward and aft as possible.
Cheers
Ian
-
:-)) Thanks Ian, looking at the pics again I think they are plumb.
Ed :D
-
{:-{ Hello (again)
On a model is it done the same way as below on the real thing then? Where the little tapered liner is does that just fill with glue I spose? {:-{ It will be very tiny.
Oh and would the lap joint be between frames please , not fastened to the frame ?
thanks, Ed. :-))
-
:-) Hello, just received details from NMM about plans for these boats, can someone please tell me if a shell expansion plan would show the bottom of the hull too ? or just the sides :((
thanks ,
Ed :-))
-
The shell expansion should show the plates from keel to gunwale. There's a photo of a chunk of the one I had, here (http://personal.strath.ac.uk/andrew.goddard/dreadnought/plating1.html).
Andy
-
:-)) Thanks, I will send fer it then.
Ed.
-
Well me plating expansion plan came this week, very interesting stuff, just need to figure it out now {-) In particular the propellor tunnels look very confusing.
Does anyone please know how to convert plate gauge in Lb's per square foot into a thickness in inches etc? they are all given as 8lbs , 10lbs etc on the plan {:-{
:-)) ta, Nick.
-
Edmund, dear soul. You have been given more advice on plating a ships hull than the average real ship builder needs. And you still want more! It's all well and good asking about plate density and so on, but do you not think that a University "think tank" may be more suited to your needs, as opposed to a forum that builds "model" boats with scant regard to the actual density of the steel plating. I could well be very wrong here, and if I am then I apologize, but I think you are "milking" this, and just doing a "wind-up". There are many books on the subject of plating. I suggest you go out and buy one. BY.
-
Hi Nick,
A plate thickness is listed in pounds-per-square-foot. So an 8lb plate masses 8 lbs per square foot. How thick's that?
Thickness in inches = 0.0245 * number of lbs
... About a fifth of an inch.
Andy, not being Bryan Youngish ok2
-
Thanks Andy, :-)) that's all I wanted to know a formula, I read somewhere that 10lb was ¼" thick so this tallies. :-)) Ed.
-
Nick,
The Imperial figure a Naval Architect would use for mild steel is 490lb/cub. ft. Knowing that, you can calculate the thickness for any given steel weight. 8lbs/sq.ft. is indeed for all practical purposes 0.2" and 10lb/sq.ft is 0.25".
Having said that, the only people for whom this is relevant are shipbuilders/repairers who want to quote on a job or for naval architects performing stability calculations. At our scales, I would argue that differences in plate thicknesses are marginal and, I would suggest, that in most cases 'if looks right, then it is right'. Trust your instincts and your eyeballs.
Hope this helps,
Barry M (Definitely not Victor Meldrew)