A question on drop planks

[apprentice]

In the article "Planking a bluff bow" by Colin Lloyd, there are pictures showing full drop planks in a full size ship. In the last photo of the article the drop planks were highlighted in blue. Two drop planks start from the same point. At the tip where the two planks join up with the half drop plank there are four 'outlets'.

 

Is this not a violation of not more than three 'outlets' rule for planking? Or is it that the rule need not be straightly observed?

 

Thank you for clearing up this point for me.

[russ]

I think by "outlets" you mean strakes of planking. That is what I saw in that photograph. There were four strakes of planking between the dropped planks.

 

The only rule of which I am aware was the Lloyd's rule that said no butts in the planking to be on the same frame unless there were three strakes in between the butts. I think they wanted at least three strakes between plank butts that ocurred on the same frame. Is that what you are after?

 

Russ

[apprentice]

Hi Russ

 

Yes that is what I meant. As I understand it, a butt joint should be form with not more than three strakes, and that a joint should not line up with the one below or above it unless there are three strakes between them. I thought these rules are meant to minimise water sippage into the hull, the same as the half strake width rule.

[russ]

I am pretty sure this is a hull strength issue. The three strakes rule was probably meant to be a minimum so as not to have too many planks butting on the same frame too close together. If it is meant to be interpreted as a minimum, then you could have more than three strakes between planking butts, but not less than. In any event, I would think that fewer plank butts on a hull would be desirable for that seepage issue. Let us see if someone with first hand knowledge might know better.

 

Also, keep in mind that the ship in the photograph is a modern replica and it has to conform to whatever are the current rules in order to get certification.

 

Russ

[apprentice]

Hi Russ

 

Come to think of it, three strikes are the minimum. number to form a butt joint. Four is possible, but above four it is difficult to imagine

[russ]

In that photo, they used four strakes between the drop planks and the butt joints as I recall, so that would fit. I think they had to work within the rules as best they could. So long as they did not violate the rules, they were okay.

 

Russ