Width in the bend

[rudybob]

I have cut spiled planks from a flat sheet. It seems to me that as I bend them around the bow I MUST keep their width in the bend the same as the width of any planks I have not cut out ie the straight planks that came with the kit. I did so using dividers. I am working with the second garboard plank ie the one above the garboard. I know that all planks don't have to be the same width I am concerned with the bend. If this is unclear I am out of luck because I can't explain it better. Please don't suggest I look at someone's video :-) 

I really only need a yes or no.

Thanks

 

[Bob Cleek]

I don't know about anybody else, but I'm not sure what you mean by "as I bend them around the bow I MUST keep their width in the bend the same as the width of any planks I have not cut out ie the straight planks that came with the kit." Pictures would help.

 

The "straight planks that came with the kit" only are useful for slab-sided areas where you'd may as well be laying hardwood floor or clapboard siding. On the other hand, if you are spiling your planks from a flat sheet, you should get a plank that fits perfectly, bend or not, since you've spiled the exact shape required. Are you sure you are spiling correctly? Have you evenly divided every frame shape by the number of planks that should be required to plank the hull? If so, your plank shapes should be fine. If you are spiling from an elevation plan, the plank seams may all look parallell to the baseline of the drawing. There is no way you can accurately derive a plank shape from that because the elevation will only show the height between the plank seams as viewed orthographically. In the bows, the planks tend to be hung at a greater angle from plumb, farther away at the bottom and closer to the viewer at the top. The greater width in three dimensions rather than apparent height in two dimensions has to be taken into account. 

 

When spiling plank, the entire hull has to be "lined off." This can be done with thread or tape. The limitation as to width is only the scale width of available plank. When lining off, you have to judge the fairness of the plank seams by eye. There isn't any rule that every seam is going to be the same width, except perhaps amidships on a large vessel. When you have "lined off" all your plank seams, you can then measure the width of the plank at each seam intersection on a frame or bulkhead. This is how you account for the actual shape of a plank on a curved surface that has been drawn flat in two dimensions on the plans.

 

Hope this helps. If not... never mind. I had to guess at what the problem was. 

Edited February 23, 2023 by Bob Cleek

[Jim Lad]

What sort of ship arr wtalking about, Bob. in most ships, the bow and stern are just the areas where we see the most alteration in plank width on the hull.

 

John

[Jaager]

That you are having a problem -  it suggests that you are doing edge bending.  If you are doing the spilling correctly, there should be no edge bending.  The stock that is being spilled probably needs to be twice as wide as the plank that is derived from it, for some of them.

Wood resists edge bending.  It will twist rather than do it.

 

The garboard is key.  The top edge is straight.  Along the touch of the keel, the bottom edge is straight.  When the rabbet arcs up with the stem and cants up with the sternpost - all of the shaping comes off of the bottom edge.  

Also, I am thinking that it might be a good idea to leave the width of the garboard out of any width reduction.  Use the planking fan on the planks between the bottom of the wale and the top of the garboard?

[Bob Cleek]

45 minutes ago, Jim Lad said:

What sort of ship arr wtalking about, Bob. in most ships, the bow and stern are just the areas where we see the most alteration in plank width on the hull.

 

John

Absolutely. As I mentoned, I really don't understand what the problem is.  He needs to explain it more understandably.

[allanyed]

11 hours ago, Bob Cleek said:

He needs to explain it more understandably.

I agree.

 

14 hours ago, rudybob said:

Please don't suggest I look at someone's video 🙂

Would you consider reading the article on spiling by David Antscherl in the Articles database here at MSW?  It very clearly explains lining off the hull and spiling the planks. 

 

Allan

 

 

[rudybob]

 It seems to me that as I bend them around the bow I MUST keep their width in the bend the same as the width of any planks I have not cut out ie the straight planks that came with the kit. Is that true?

[Paul Le Wol]

Hi rudybob, as you approach the stem, the planks will become narrower. How much narrower depends on the vessel you are modeling. It doesn’t matter whether you have spiled the plank or whether you have tapered and edge bent the plank, its width will still have to change. So my answer to your question is no, that is not true.