Half-Hull Models

[PeterGR]

Another lockdown project looming!

I am going to try knock-up a representation half-hull model of a former boat I had.
Any one tried before?
I have a mix of limited line plans + photos to get started.

Not looking for 100% accuracy!
I found a book online I am waiting to arrive for a guide.

I don't have any indication of lifts or sections so I was going to mark out as much as I can on a scaled block of wood then hack and carve away at it.

 

[Neeves]

Make up a set of accurate profiles from thin plastic sheet, robust paper file dividers, or made from very thin ply. These will give you the template to work to.

Good luck

Jonathan

 

[Laminar Flow]

If you have the line drawings you might trace the waterlines onto boards scaled to the correct thickness, i.e. to the vertical distance between the waterlines.

Make a photo copy for each waterline, cut it out and glue it to its board and cut it out.

Stack them and carve, sand, grind off the overstand back to the line.

Band saw works best.

Easy and 100% accurate.

 

[Babylon]

What was your former boat?

 

[Buck Turgidson]

I made a CAD model rather than a wooden one.
Would have been faster building a new full size boat!!

link

 

[TernVI]

One old-school method of making models was to draw sets of lines, then simply stack a set of of thin planks cut to the lines. Then sand the corners off.
At least a half model avoids the problem of getting it symmetrical!

A CNC router? Some sort of pantograph copying device?

 

[Hacker]

If you have lines drawings then there are 2 approaches. One is to build half moulds and fill in the gaps. The other is to work out how far the planking is from the centreline and then use this to put drill holes into a block of wood to give a carving depth. The trick is that you need to drill from the outside of the block so that the end of the drill hole represents the outside of the plank. You need to be able to do a calculation of the outside of the block minus the centreline to plank to give you the correct depth.

 

[Sandro]

Someone can remember the origin of half models.
In old times, to design the lines of a new shipbuilding project, the shipwright stacked a few small planks fastened with trenails, then, following his idea, carved/filed the shape of one half (usually the starbord) of the hull with the planks parallel to the waterline, until he was satisfied.
After disassembling the stack, the waterlines were traced from each plank on paper or cardboard or ply and then scaled to full size for building.
No 3D rendering then.