Neil

 

The model will be in the Steam Packet office at the Sea Terminal Building, Douglas.

Can you email the photos to me?

 

Paul

Hi Neil

 

PM sent and Ive rung Dr John who lives on on the rock and he will have a look around this week.

 

Paul

Hello NEIL

 

Last year at the Birchwood show, there was a working model of the Duke of Northumberland and it was made by a Mr Jones of Holyhead and I think he can be reached via the Holyhead Maritime museum.

 

If this is of any use?

 

Bob

Hello Neil.

That is what I did using Delftship then Freeship (both have the same origin, but you now have to pay for delftship).

The first decision to be made is chine or non-chine – I did this from studying many photographs, the best being ones where the boats had been pulled up onto the mud, propped up with poles, and workers scraping off the seaweed etc that fouls the hulls, and adding their mixture of hot animal fat mixed with lime to control the Toredo wood ship worm. This is why they look white below the waterline. I chose non-chine.

Then you need to indicate how many stations you will need – I chose 20 so that I could control the overall shape to keep it ‘true’. I forget the technical term (sorry) but the program provides you with a few “major” control lines that you push and squeeze to the shape you want, so that the cross-sections are approximately what you want (as you define from studying the photos). The side view allows you to adjust the sheerlines, deck location, rake of stern and bow etc (again guided by photos). The plan view (top view) allows you to nudge the beam towards the length-width ratio photos tell you it should be, the location of maximum beam, the shapes of the bows and transom or pointed or rounded stern. Moving the major control lines is good because the other lines move in response to the changes you are deliberately making. Be aware that you are working in a 3D environment, so should frequently check the other views to see that what you are doing is what you want to have happen!

Gaining symmetry is not a problem as you are really only working on half of the model, the other portion being produced as a mirror image (this is only a nuisance when you are designing asymmetric catamaran hulls.)

I used the 3D program mainly for creating the complex-curve portions, leaving such aspects as superstructure etc till later on, once I had created full-model size plans.

One difficulty I experienced (and this may have stemmed from lack of understanding of this aspect of the FreeShip program) was that it produced a bitmapped image of the complete plan (side view, forard and aft hull section halves, plan half) to a certain size that was not at the full-size I wanted for my model. The problem with this is that when enlarged each of the linesbecome jagged and blocky and thick. My solution was to import the image into a program that could do vector drawing (such as Photoshop). The big advantage of this is that the lines are mathematical so enlarging considerably still produces thin accurate curved and straight lines.

Cheers, Keith.

 

Hi JC Uknz.

You suggested: “If you have a crude drawing which ‘jags’ when enlarged one solution is to get the editing programme to ‘re-sample’ or ‘interpolate’ using a greater number of ‘dots per inch’ [ oir cm ]    This is possible with any of the better editing programmes, my choice is Paint Shop Pro and any version from v.7 onwards will do it for you, maybe earlier versions too.”

An excellent idea, but I did try that and was amazed at the extent of the change produced by the procedure. What happened was that before enlarging I had created the mirror half of each bulkhead, so that they were then perfectly symmetrical. I then enlarged as you suggest, and it looked fine until I folded the printout for the bulkheads along the centreline to check symmetry, and was dismayed to see how different each half had become. They were now quite asymmetrical. I can’t give you a measurement as I destroyed the results and started again, but it was considerable.

However, by working with vector lines, the positioning of the lines is exact so enlargement did not destroy symmetry (because the dot positions are determined mathematically by the program). For the 3D lines of a hull to prove “true” where the water flow will be as best as possible, I think it is worth worrying.

However, perhaps I am being too fussy, because my building procedure, once the plans have been created, is far from fine and accurate!

Cheers, Keith

Hello Chaps

 

Last year, Les Jones came to our club and gave us a nice  lecture on his models and model boat construction, unfortuneately I was away at the time and couldn`t attend.

 

He brought his model masterpieces with him, for all to examine

 

 

Just thought I`d mention it…….Bob

Hi JC Uknz.

My problem with combining enlargement of a bit image (made of many pixels of colours) with then mirroring the result, is that even though the final bulkheads will be symmetrical, they may not be “correct” when compared with one another along the hull, and so result in bumps and hollows that would result in the hull lines running ‘not true’.

Using vector drawing guarantees accuracy through the enlargement process.

Do you use Photoshop? If so, I would be happy to offer a few pointers for using the vector drawing aspect of the program.

Regards, Keith