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HMS Elephant, 74 (1786) News

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JosephH

Sun Feb 25 2018, 02:04am

Registered Member #4876

Joined: Fri Dec 23 2016, 03:37am
Posts: 996

Hey guys I thought I would share some news with you on a project I been messing with this week while on vacation.

I been trying to learn to draw up ships the way they did back when. Most of it is simple for laying out the Sheer Plan, the hard part comes when trying to loft out the Stations.
Several of us played around with all the tables in Steel's books and other than a frame here or there most of his tables are off.

This brings us to present day:

A while back Don Howe generously shared his drawings and ship's contract for the HMS Elephant a 74 gunner and at the Battle of Copenhagen she was Admiral Nelson's Flagship.

So I decided to try something this week and see if I could reverse engineer the station lofting. As the drawings are fairly clean and sharp when I bring them into cad for some reason the always lose quality, however since the drawings were fairly decent I can make out everything good enough.

First I started by adjusting the drawings for Skew and warpage. I brought them into corel draw as that is more of a photo program, though it is very good for cad work, but it does not degrade the drawings very much and I could use this to check dimensions and adjust the size of the sheet.

after much trial and error I got them to where they are almost perfect, but cant get perfect as various areas can adjust seperate of the entire thing but it is within 1/4" at full scale.

Then I drew the Sheer Plan and the Half-Breadth plan using steels dimensions for reference and adjusting them for the Elephant where there was significant deviation IE the bow area and transom area.

JosephH

Sun Feb 25 2018, 02:20am

Registered Member #4876

Joined: Fri Dec 23 2016, 03:37am
Posts: 996

So why you ask did i bother with the Sheer and Half-Breadth drawings if I wanted to do the stations?

The reason is you need certain information from each of the 3 drawings in order to verify and fair in the stations.

So that brings me to the next step I needed to do and that was to get basic information assembled to help me draw the stations.

Since we know steel's tables are off I couldn't use those. However, what I could do is after I draw up the stations, is to enter the data into a table that could be shared with others who may want to use them to draw up some frames.

Being one that is totally anal when I do models I figured if I am going to do it I will do it right and make an Excel Template that I can save and use for each ship I may want to do. Since I was going to do that I figured why not make a ship specific scantlings template that I can share with others so that we could open the template and enter the data for the ship we are working on so that it is all there without sifting through pages and pages of text in books looking for the proper dimensions every time we need one.

This needed to be in a logical order so that it covers the area one would be working on, again so that people don't have to search around. For this I decided to Use the templates Ed Tosti has for the Naiad as a reference. I had bought both his books and been using them to learn how to draw up ships and his templates are in a logical order.

I did not totally go exactly as his because I added stuff his didn't have to make them more useful for total ship layout. I asked Arthur over at MSW to put it up on the NBM site for download so anyone that wants it can grab it there.

[ Edited Sun Feb 25 2018, 04:35am ]

JosephH

Sun Feb 25 2018, 02:33am

Registered Member #4876

Joined: Fri Dec 23 2016, 03:37am
Posts: 996

as you can see they are quite detailed. in a couple of the sheets I added data as a placeholder to give an example of how it is entered and is easy to delete once you understand and add your own data.

in the 3rd header line the 48 represents the scale of the model though all dimensions are full scale, a person could add another column next to it for model dimensions which will save converting later. I would just set up a formula for the extra column so as you fill in the full scale it automatically converts it. I have more to do on the template but i figured it is easier to leave the scale conversion out because not everyone may know how to edit the formula for the scale they are building. I may make several templates for the most common scales 1/96, 1/60, 1/48. 1/32, 1/24 that way you can just download the zipped file and use the one you need.

the sheets are labelled for the job you would be working on at the time to make things easier. I didn't rename the sheet tabs at the bottom of the spreadsheet but you could do it to make it easier to find the sheet tab you want.

[ Edited Sun Feb 25 2018, 02:33am ]

JosephH

Sun Feb 25 2018, 02:35am

Registered Member #4876

Joined: Fri Dec 23 2016, 03:37am
Posts: 996

oops forgot the screenshots

JosephH

Sun Feb 25 2018, 02:44am

Registered Member #4876

Joined: Fri Dec 23 2016, 03:37am
Posts: 996

So now that I had all my data I set up the body plan for lofting the stations. Using the data from the other 2 plan sheets, and the markings on the plans themselves I was able with minimum head banging get my stations to draw up and pretty accurately match the body plan. Since I am actually drawing the body parts and not tracing I have all the reference info for each station that when complete I can add to my template and also to put out a body plan table for a 74 gun ship with accurate dimensions so anyone can loft up the stations. I may use this same technique and do it for several types of ships as I come across some high quality admiralty drawings that I can reverse engineer. Now steels is for a ship of 176' however the Elephant is only 168' so the dimensions and half breadth will be for whichever ship plan I am working from and you can alter to suit your needs just like you have to with steels data

JosephH

Sun Feb 25 2018, 02:48am

Registered Member #4876

Joined: Fri Dec 23 2016, 03:37am
Posts: 996

So that is what I did on my vacation and once I finish the body plan and create the tables I will share both probably up on NBM as we are trying to set that up as a one place for everything data center. Right now there are some guys working on putting all Harold Hahn's info up there for people to have access too.

JosephH

Sun Feb 25 2018, 06:51am

Registered Member #4876

Joined: Fri Dec 23 2016, 03:37am
Posts: 996

Everything is going good. I will have to do a 3D Loft to get good outlines for the ones super close to the DF as those are too degraded to see well. once I get those I will bring them back over to the body plan and reverse engineer it like I doing with the others, however its going really good on the reversing it just remains to be seen how fair they are

JosephH

Sun Feb 25 2018, 08:53am

Registered Member #4876

Joined: Fri Dec 23 2016, 03:37am
Posts: 996

ok got all the aft side done just need to set up the loft to get the last 5 stations finished

JosephH

Mon Feb 26 2018, 08:36pm

Registered Member #4876

Joined: Fri Dec 23 2016, 03:37am
Posts: 996

so it is my last day of vacation and today I got the aft waterlines and frames all drawn and fared in. I just need to set the keel section of the stations to be sure they correct for proper taper.

Everything looking great and didnt take hardly any adjusting to fare them in so the aft lofting dimensions should be pretty good to go. Now onto the front section after I Loft the back just to get a visual