lehmann

Wood has a low thermal expansion coefficient - meaning the size does not change much with temperature.   However, the temperature of the air affects the amount of water vapor in the air (relative humidity), which will, over time, change the moisture content of wood.   As a result, you may see changes in the size of the wood if you leave it in the garage at different temperatures.  
 
Cabinet makers have long know to store wood at the same moisture content as it will eventually be used.  In most houses, that's about 6% - 8% moisture content.  Since, it takes time for the moisture content of wood to change, the first thing  to do is keep your wood supply in the house, not the garage.  Second, if you can, keep the model in the house when you're not working on it.  
 
There may be another trick - over-dry the planks before putting them on the hull.   As the planks come back to equilibrium moisture content, they will swell slightly, closing up the seams, just as planks on a real ship swell when the hull is put in the water.  There was a comment earlier that this may cause the planking to buckle, but I doubt it.  
 
FYI, a version of this trick is used by chair-makers to securely hold the bent backs into the seat.  The ends of the back are shaped slightly over-sized to the holes in the seat.  The backs are then dried in a small oven, just heated by light bulbs, to perhaps 2% moisture content.  With the slight shrinkage that occurs the ends now fit (snugly) into the holes, but when the moisture content comes back to 6%, the end is solidly locked in place.  
 
So, if you're too impatient to wait for the planks to dry, make a small oven above a light bulb (or perhaps a heat lamp or a halogen).  The drying time would be pretty fast for pieces as thin as planking and you may get the added benefit of over-dried planks.  

Wood has a low thermal expansion coefficient - meaning the size does not change much with temperature.   However, the temperature of the air affects the amount of water vapor in the air (relative humidity), which will, over time, change the moisture content of wood.   As a result, you may see changes in the size of the wood if you leave it in the garage at different temperatures.  
 
Cabinet makers have long know to store wood at the same moisture content as it will eventually be used.  In most houses, that's about 6% - 8% moisture content.  Since, it takes time for the moisture content of wood to change, the first thing  to do is keep your wood supply in the house, not the garage.  Second, if you can, keep the model in the house when you're not working on it.  
 
There may be another trick - over-dry the planks before putting them on the hull.   As the planks come back to equilibrium moisture content, they will swell slightly, closing up the seams, just as planks on a real ship swell when the hull is put in the water.  There was a comment earlier that this may cause the planking to buckle, but I doubt it.  
 
FYI, a version of this trick is used by chair-makers to securely hold the bent backs into the seat.  The ends of the back are shaped slightly over-sized to the holes in the seat.  The backs are then dried in a small oven, just heated by light bulbs, to perhaps 2% moisture content.  With the slight shrinkage that occurs the ends now fit (snugly) into the holes, but when the moisture content comes back to 6%, the end is solidly locked in place.  
 
So, if you're too impatient to wait for the planks to dry, make a small oven above a light bulb (or perhaps a heat lamp or a halogen).  The drying time would be pretty fast for pieces as thin as planking and you may get the added benefit of over-dried planks.  

One observation that has been missed is that the width of the strips is equal to the vertical distance between the ratlines.  Or, more precisely stated, the distance between the knots.  As long as you can set the strips level, there is no need to use a paper grid.

Also, commercial drawing machines flood the die with oil, which lubricates the hole and takes away heat.   Even for hand drawing of metals, some oil, wax or grease is recommended to reduce wear of the holes and to reduce the required pulling force.  This is, of course, messy if done by hand, so I can see how a drawing bench would be desirable.  

Also, commercial drawing machines flood the die with oil, which lubricates the hole and takes away heat.   Even for hand drawing of metals, some oil, wax or grease is recommended to reduce wear of the holes and to reduce the required pulling force.  This is, of course, messy if done by hand, so I can see how a drawing bench would be desirable.  

Also, commercial drawing machines flood the die with oil, which lubricates the hole and takes away heat.   Even for hand drawing of metals, some oil, wax or grease is recommended to reduce wear of the holes and to reduce the required pulling force.  This is, of course, messy if done by hand, so I can see how a drawing bench would be desirable.  

Roger,
They are available from Lee Valley.... http://www.leevalley.com/en/wood/page.aspx?p=32681&cat=1,50230.  Now,  $36 CDN, though.  I have the set and they're very nice.  I bought these instead of LV's miniature spoke shave.

Roger,
They are available from Lee Valley.... http://www.leevalley.com/en/wood/page.aspx?p=32681&cat=1,50230.  Now,  $36 CDN, though.  I have the set and they're very nice.  I bought these instead of LV's miniature spoke shave.

Roger,
They are available from Lee Valley.... http://www.leevalley.com/en/wood/page.aspx?p=32681&cat=1,50230.  Now,  $36 CDN, though.  I have the set and they're very nice.  I bought these instead of LV's miniature spoke shave.

Yellow cedar is actually a cypress (Chamaecyparis nootkatensis).  However, while cypress is usually associated with shrubs, yellow cedar trees can be huge.  
 
http://vancouverislandbigtrees.blogspot.ca/2013/05/worlds-largest-yellow-cedars.html
 
You could probably build a model out of one branch.  (There's a few growing down the street and I keep my eye open after wind storms)
 
These trees can produce large clear timbers and boards.  It's also hard and rot resistant.  As a result it is a very good material for ship building, especially planking.    
 
I've done carving in yellow cedar and it is hard and fine grained, so it holds details very well, and has no pores, as hardwoods have.   Fairly uniform in color, but may get mineral streaks. It is dense, similar to black walnut, so expect your finger tips to get sore when carving.  The grain is generally straight, but can get some swirling.  Can have a quite pungent smell, as are most cypresses and junipers  (Tennessee red cedar is actually a juniper).  
 
Overall, a yellow cedar should be a very good wood for model shipbuilding.  Actually, it's the only wood I've seen that can be used on full size and well as model ships.  Many years ago I stored away a large box of yellow cedar cuttings, and some 2x4's that showed up in a load of Douglas fir boards, with the intention of using it for a plank on frame model.  If I need more, a few local sawmills cut it and it is stocked locally.  Prices for good grade boards are similar to hardwoods, such as red oak.

One observation that has been missed is that the width of the strips is equal to the vertical distance between the ratlines.  Or, more precisely stated, the distance between the knots.  As long as you can set the strips level, there is no need to use a paper grid.

One observation that has been missed is that the width of the strips is equal to the vertical distance between the ratlines.  Or, more precisely stated, the distance between the knots.  As long as you can set the strips level, there is no need to use a paper grid.

One observation that has been missed is that the width of the strips is equal to the vertical distance between the ratlines.  Or, more precisely stated, the distance between the knots.  As long as you can set the strips level, there is no need to use a paper grid.

Yellow cedar is actually a cypress (Chamaecyparis nootkatensis).  However, while cypress is usually associated with shrubs, yellow cedar trees can be huge.  
 
http://vancouverislandbigtrees.blogspot.ca/2013/05/worlds-largest-yellow-cedars.html
 
You could probably build a model out of one branch.  (There's a few growing down the street and I keep my eye open after wind storms)
 
These trees can produce large clear timbers and boards.  It's also hard and rot resistant.  As a result it is a very good material for ship building, especially planking.    
 
I've done carving in yellow cedar and it is hard and fine grained, so it holds details very well, and has no pores, as hardwoods have.   Fairly uniform in color, but may get mineral streaks. It is dense, similar to black walnut, so expect your finger tips to get sore when carving.  The grain is generally straight, but can get some swirling.  Can have a quite pungent smell, as are most cypresses and junipers  (Tennessee red cedar is actually a juniper).  
 
Overall, a yellow cedar should be a very good wood for model shipbuilding.  Actually, it's the only wood I've seen that can be used on full size and well as model ships.  Many years ago I stored away a large box of yellow cedar cuttings, and some 2x4's that showed up in a load of Douglas fir boards, with the intention of using it for a plank on frame model.  If I need more, a few local sawmills cut it and it is stocked locally.  Prices for good grade boards are similar to hardwoods, such as red oak.

Yellow cedar is actually a cypress (Chamaecyparis nootkatensis).  However, while cypress is usually associated with shrubs, yellow cedar trees can be huge.  
 
http://vancouverislandbigtrees.blogspot.ca/2013/05/worlds-largest-yellow-cedars.html
 
You could probably build a model out of one branch.  (There's a few growing down the street and I keep my eye open after wind storms)
 
These trees can produce large clear timbers and boards.  It's also hard and rot resistant.  As a result it is a very good material for ship building, especially planking.    
 
I've done carving in yellow cedar and it is hard and fine grained, so it holds details very well, and has no pores, as hardwoods have.   Fairly uniform in color, but may get mineral streaks. It is dense, similar to black walnut, so expect your finger tips to get sore when carving.  The grain is generally straight, but can get some swirling.  Can have a quite pungent smell, as are most cypresses and junipers  (Tennessee red cedar is actually a juniper).  
 
Overall, a yellow cedar should be a very good wood for model shipbuilding.  Actually, it's the only wood I've seen that can be used on full size and well as model ships.  Many years ago I stored away a large box of yellow cedar cuttings, and some 2x4's that showed up in a load of Douglas fir boards, with the intention of using it for a plank on frame model.  If I need more, a few local sawmills cut it and it is stocked locally.  Prices for good grade boards are similar to hardwoods, such as red oak.

Yellow cedar is actually a cypress (Chamaecyparis nootkatensis).  However, while cypress is usually associated with shrubs, yellow cedar trees can be huge.  
 
http://vancouverislandbigtrees.blogspot.ca/2013/05/worlds-largest-yellow-cedars.html
 
You could probably build a model out of one branch.  (There's a few growing down the street and I keep my eye open after wind storms)
 
These trees can produce large clear timbers and boards.  It's also hard and rot resistant.  As a result it is a very good material for ship building, especially planking.    
 
I've done carving in yellow cedar and it is hard and fine grained, so it holds details very well, and has no pores, as hardwoods have.   Fairly uniform in color, but may get mineral streaks. It is dense, similar to black walnut, so expect your finger tips to get sore when carving.  The grain is generally straight, but can get some swirling.  Can have a quite pungent smell, as are most cypresses and junipers  (Tennessee red cedar is actually a juniper).  
 
Overall, a yellow cedar should be a very good wood for model shipbuilding.  Actually, it's the only wood I've seen that can be used on full size and well as model ships.  Many years ago I stored away a large box of yellow cedar cuttings, and some 2x4's that showed up in a load of Douglas fir boards, with the intention of using it for a plank on frame model.  If I need more, a few local sawmills cut it and it is stocked locally.  Prices for good grade boards are similar to hardwoods, such as red oak.

Yellow cedar is actually a cypress (Chamaecyparis nootkatensis).  However, while cypress is usually associated with shrubs, yellow cedar trees can be huge.  
 
http://vancouverislandbigtrees.blogspot.ca/2013/05/worlds-largest-yellow-cedars.html
 
You could probably build a model out of one branch.  (There's a few growing down the street and I keep my eye open after wind storms)
 
These trees can produce large clear timbers and boards.  It's also hard and rot resistant.  As a result it is a very good material for ship building, especially planking.    
 
I've done carving in yellow cedar and it is hard and fine grained, so it holds details very well, and has no pores, as hardwoods have.   Fairly uniform in color, but may get mineral streaks. It is dense, similar to black walnut, so expect your finger tips to get sore when carving.  The grain is generally straight, but can get some swirling.  Can have a quite pungent smell, as are most cypresses and junipers  (Tennessee red cedar is actually a juniper).  
 
Overall, a yellow cedar should be a very good wood for model shipbuilding.  Actually, it's the only wood I've seen that can be used on full size and well as model ships.  Many years ago I stored away a large box of yellow cedar cuttings, and some 2x4's that showed up in a load of Douglas fir boards, with the intention of using it for a plank on frame model.  If I need more, a few local sawmills cut it and it is stocked locally.  Prices for good grade boards are similar to hardwoods, such as red oak.

Yellow cedar is actually a cypress (Chamaecyparis nootkatensis).  However, while cypress is usually associated with shrubs, yellow cedar trees can be huge.  
 
http://vancouverislandbigtrees.blogspot.ca/2013/05/worlds-largest-yellow-cedars.html
 
You could probably build a model out of one branch.  (There's a few growing down the street and I keep my eye open after wind storms)
 
These trees can produce large clear timbers and boards.  It's also hard and rot resistant.  As a result it is a very good material for ship building, especially planking.    
 
I've done carving in yellow cedar and it is hard and fine grained, so it holds details very well, and has no pores, as hardwoods have.   Fairly uniform in color, but may get mineral streaks. It is dense, similar to black walnut, so expect your finger tips to get sore when carving.  The grain is generally straight, but can get some swirling.  Can have a quite pungent smell, as are most cypresses and junipers  (Tennessee red cedar is actually a juniper).  
 
Overall, a yellow cedar should be a very good wood for model shipbuilding.  Actually, it's the only wood I've seen that can be used on full size and well as model ships.  Many years ago I stored away a large box of yellow cedar cuttings, and some 2x4's that showed up in a load of Douglas fir boards, with the intention of using it for a plank on frame model.  If I need more, a few local sawmills cut it and it is stocked locally.  Prices for good grade boards are similar to hardwoods, such as red oak.

Yellow cedar is actually a cypress (Chamaecyparis nootkatensis).  However, while cypress is usually associated with shrubs, yellow cedar trees can be huge.  
 
http://vancouverislandbigtrees.blogspot.ca/2013/05/worlds-largest-yellow-cedars.html
 
You could probably build a model out of one branch.  (There's a few growing down the street and I keep my eye open after wind storms)
 
These trees can produce large clear timbers and boards.  It's also hard and rot resistant.  As a result it is a very good material for ship building, especially planking.    
 
I've done carving in yellow cedar and it is hard and fine grained, so it holds details very well, and has no pores, as hardwoods have.   Fairly uniform in color, but may get mineral streaks. It is dense, similar to black walnut, so expect your finger tips to get sore when carving.  The grain is generally straight, but can get some swirling.  Can have a quite pungent smell, as are most cypresses and junipers  (Tennessee red cedar is actually a juniper).  
 
Overall, a yellow cedar should be a very good wood for model shipbuilding.  Actually, it's the only wood I've seen that can be used on full size and well as model ships.  Many years ago I stored away a large box of yellow cedar cuttings, and some 2x4's that showed up in a load of Douglas fir boards, with the intention of using it for a plank on frame model.  If I need more, a few local sawmills cut it and it is stocked locally.  Prices for good grade boards are similar to hardwoods, such as red oak.

Yellow cedar is actually a cypress (Chamaecyparis nootkatensis).  However, while cypress is usually associated with shrubs, yellow cedar trees can be huge.  
 
http://vancouverislandbigtrees.blogspot.ca/2013/05/worlds-largest-yellow-cedars.html
 
You could probably build a model out of one branch.  (There's a few growing down the street and I keep my eye open after wind storms)
 
These trees can produce large clear timbers and boards.  It's also hard and rot resistant.  As a result it is a very good material for ship building, especially planking.    
 
I've done carving in yellow cedar and it is hard and fine grained, so it holds details very well, and has no pores, as hardwoods have.   Fairly uniform in color, but may get mineral streaks. It is dense, similar to black walnut, so expect your finger tips to get sore when carving.  The grain is generally straight, but can get some swirling.  Can have a quite pungent smell, as are most cypresses and junipers  (Tennessee red cedar is actually a juniper).  
 
Overall, a yellow cedar should be a very good wood for model shipbuilding.  Actually, it's the only wood I've seen that can be used on full size and well as model ships.  Many years ago I stored away a large box of yellow cedar cuttings, and some 2x4's that showed up in a load of Douglas fir boards, with the intention of using it for a plank on frame model.  If I need more, a few local sawmills cut it and it is stocked locally.  Prices for good grade boards are similar to hardwoods, such as red oak.

Yellow cedar is actually a cypress (Chamaecyparis nootkatensis).  However, while cypress is usually associated with shrubs, yellow cedar trees can be huge.  
 
http://vancouverislandbigtrees.blogspot.ca/2013/05/worlds-largest-yellow-cedars.html
 
You could probably build a model out of one branch.  (There's a few growing down the street and I keep my eye open after wind storms)
 
These trees can produce large clear timbers and boards.  It's also hard and rot resistant.  As a result it is a very good material for ship building, especially planking.    
 
I've done carving in yellow cedar and it is hard and fine grained, so it holds details very well, and has no pores, as hardwoods have.   Fairly uniform in color, but may get mineral streaks. It is dense, similar to black walnut, so expect your finger tips to get sore when carving.  The grain is generally straight, but can get some swirling.  Can have a quite pungent smell, as are most cypresses and junipers  (Tennessee red cedar is actually a juniper).  
 
Overall, a yellow cedar should be a very good wood for model shipbuilding.  Actually, it's the only wood I've seen that can be used on full size and well as model ships.  Many years ago I stored away a large box of yellow cedar cuttings, and some 2x4's that showed up in a load of Douglas fir boards, with the intention of using it for a plank on frame model.  If I need more, a few local sawmills cut it and it is stocked locally.  Prices for good grade boards are similar to hardwoods, such as red oak.

However, a recessed edge on a carrot has been rabbited. (old cabinet maker joke).

However, a recessed edge on a carrot has been rabbited. (old cabinet maker joke).

However, a recessed edge on a carrot has been rabbited. (old cabinet maker joke).

The estimation of load water line and tonnage (displacement or cargo capacity) is just that - an estimation to as a check on the designer's intention that the vessel could fulfill its role.  Nowadays, we understand the physics, the mathematics have been simplified (even without the aid of computers to do the repetitive number crunching), and we have accurate measurements to prove everything.   At the time there were many unknowns and uncertainties, but the the designer still needs some assurance he can be proud of the design, or at the least, not be sued.   These various formulas are nothing more than first approximations that included some basic factors that were easy to measure mixed with a few fudge factors that make the numbers fit with "experience" or a consensus of opinion.  The ease of measurement is important in that different people would get the same results and those who didn't have access to more sophisticated measurement tools were not left at a disadvantage.  
 
As an engineer, I still do a "back of the envelope" calculation like this as a reality check of a computer model analysis.   You may not realize that some rules in standards, such as the National Building Code, are still based on a consensus of experts when the theoretical and experimental data does not provide sufficient information.  
 
The fudge factors would, I assume, vary depending on region, or predominant ship design.  Factors that "work" for shallow draft coastal boats don't work for deep water clipper ships.  However, customs and insurance officials like to have a common formula that can be easily and uniformly applied by their inspectors.  The question arises, who chooses which rule to use?  Ship owners pick the lowest when charged for customs and insurance, and the highest when impressing a customer.  The same is done now in all aspects of business, even if standards organizations are tasked with choosing an evaluation method: there are always factions trying to influence the choice.   It also reminds me of the rating formulas for racing yachts, which resulted in some strange looking boats.   I recall reading somewhere that tonnage rules also produced some un-seaworthy distortions as owners found hull shapes that maximized actual cargo capacity relative to the rated tonnage.  As with all business performance measures, there will always be someone who "games" the formula, resulting in an unintended consequence.
 
My conclusion is that tonnage rules are a different animal than displacement calculations for load waterline or trim.  The tonnage rules have a strong connection to politics and influence.   On the performance side, it may be possible with computational fluid dynamics programs to choose the best displacement and trim for best sailing qualities, but I doubt anyone has figured out the hull design that is the best compromise for all sea conditions, cargoes and sail trim: maybe the designers of the America's Cup boats get the closest to this ideal. Even with computer models, there are still several model ship testing basins used for experimental validation.  There is still a lot of evolution in ship design and that the key to evolution is survival - physical and economic.   The main difference between 2016 and 1816 is that designers have the tools to avoid the failures.  I'm not sure a modern designer, forced to work with wood and hemp, could design a better ship than their predecessors developed by trial and (lots of) error.