Nibbing Strake

[mikiek]

My Niagara build plans call for a nibbing strake between the edge of the deck and the waterway. I realize there are a number of ways to do this.  I actually built the deck outside the hull and will drop it in and glue it at the appropriate time. I did leave nibs on a lot of the strake ends, with the intention of making the nibbing strake fit into the nibs, rather than just glue something on top of the deck edge.

 

The plans give no indication of what the nibbing strake should be made of or even what color it should be.  I have some 1/16" boxwood sheet that I will probably use. However, rather than 1 piece from bow to stern I want to break it up into what would have been more accurate sized pieces for the time.

 

I would appreciate some feedback from you guys.....

Edited February 23, 2016 by mikiek

[mikiek]

Still thinking on this one. The space between the waterway, at it's widest, is maybe 3/16" wide. Trying to cut the nibs on one side of a strip would be most challenging. Also trying to do that with one piece of wood - even from sheet - is another obstacle.

 

I've seen some pix where the builder used several shorter planks and joined those at the ends with scarf joints. Maybe a possibility. Although trying to add a scarf joint to a 3/16" wide plank with nibs cut in it is not an appealing thought.

 

I'm also thinking maybe styrene. I lose my woodgrain but I gain some durability.

[mtaylor]

I think, that if you go with the wood, use several pieces and scarf them together. Whatever you feel good about doing, test on some scrap first.  You might even find that the 3/16" wide wood will work for you. 

[allanyed]

Mike,

 

I am really curious to see how it goes from this point to laying the prefab deck into place.   Can't say that I have ever seen a complete planked deck fit in place this way. With the round up and sheer, are you concerned about these two bends being problematic?

 

Allan

[mikiek]

Mark - I agree completely. It would not be accurate to end up with a single piece. Recommendations from research are as you say. The gotcha is carving out the nibs on one side of the plank(s) and then having enough room for a decent scarf joint. The part of the joint that I would carve on the outside of the plank would probably be doable. But the part of the joint on the inside of the plank - I would have to cut that in addition to the nibs.  The scarf joint would need to be placed strategically.

 

Allen - the deck was built on a frame with crosspieces running parallel to the bulkheads and placed about 1/4" behind where the BH would contact the deck.So there is no issue there except that I ended up cutting those crosspieces at the deck centerline so that the deck will flex slightly and take on the crown caused by the BH pieces. The tougher part was the frame added around the edge of the deck. That will lay across the BH pieces and would raise the entire deck up by the width of the frame. To get around that, I cut grooves in the BH pieces where that frame would have come into contact. So when I lay the deck in, the frame really doesn't touch anywhere. This allows the deck to take on the normal shape that the tops of the BH provide.  Even with a light coating of white glue on the deck underside, the entire structure has remained surprisingly flexible.  I do wonder what a stain and a few coats of lacquer will do to the flexibility.

[mikiek]

For posterity I will finish off my solution. There are more details in my build log along with pix.

 

The bow of the deck had a nib on every plank. I finally decided it would be problematic to try to carve this many nibs into a plank or sheet, so I sanded down every other nib. This made things more manageable but still leaves the nibbed look.

 

Then I traced out the deck outline on some styrene. I also drew an arc about 1/4" beyond the tracing. I cut this out so I ended up with a strip the length of the deck with the nibs on one edge and the straight edge about 1/4" further out. This would be my template for cutting the wood pieces.

 

As the deck edge is curved at the bow area, I had to decide how wide a wood plank to use and how those would lay on the template. Then I decided where I would have room for scarph joints and marked that on the styrene strip.

 

After that it was just a matter of cutting the wood strips. I used 1/4"x1/16" strips at the bow where all the nibs are. As the deck profile becomes straight towards the aft end I switched to 1/8"x1/16" . 

 

There was a fair amount of filing to do to get a nice flush fit with the deck. I plan to glue the nib strakes to the deck and then sand the outer edge so that the deck + strakes fit between the waterways.