Drop planks and tapering

[Captain Al]

Before I embark on cutting and installing drop planks on my Bounty, I wonder if someone can confirm for me that I understand it fully.  Clearly the idea is to reduce the number of planks (strakes) running to a given area when that area to be filled is too narrow to accommodate the number of planks required further back toward midship, and the taper to make it work would be too radical (more than half the width of the planks).  In looking over the pictures in the tutorials, it appears to me that the process is like: (1) two planks are tapered down to where they are half the width of the drop plank where they will join the drop plank. (2) a 45 degree cut is made to the ends of each of these planks, forming a 90 degree rebate where the two come together.  (3) the drop plank is cut to a 90 degree point to fit into the end of the original two planks. (4) the drop plank is itself tapered down to an appropriate width at its end point. 

 

The part that I am unsure of is this.... do the rules of tapering apply still?  Are the original two planks tapered only on their top edge?  And is the drop plank also tapered only on the top?  Is there any rule of thumb that the first two planks should be tapered to half of a full plank so that the drop plank can start by being a full width plank (with of course the 90 degree point cut)?  If the first two taper less than half a plank, then it would be impossible for a full width drop plank to fill up that 90 degree rebate.  But if the taper goes to more than half the plank width, then the drop plank must also be cut to less than its full width where it joins them.  In other words, is it true that the first two planks must taper to exactly half the width of the drop plank and that width cannot exceed (obviously) the width of the planks being used. 

[Captain Al]

No comments on this so far, so I guess I'll just proceed with the assumption I am correct on most parts.  I've found in laying out where the drop planks should go that it is not such a straight forward simple issue.  They can go anywhere.  Besides having to be on a frame, they seem to have to go where there is at least a drop of a full plank in the amount of space to fill.  If you are using 5mm planks and you do a drop plank where the difference is only 4 mm, you will have created a 1 mm gap. 

[russ]

Al:

The top edge of the plank is spiled to match the curve of the plank above it and the bottom edge is tapered so it will fit in the space for it on the frames. Other than that, I think you have it correct. You are making one plank to take the place of two where the space narrows too much to have two planks.

 

In Underhill's Plank on Frame Models volume I, there is a good description with illustrations of both stealers and drop planks.

 

Russ

Edited September 9, 2014 by russ

[Captain Al]

Thanks Russ.  I may need to get myself another piece of reference material.   I made a typo mistake in my last post.....I meant to say "they (the drop planks) can not go anywhere."  But I think you got my point.  Can you tell me what the difference between spiling and tapering is?  I can't seem to get straight what spiling is -- I thought it was the process of taking measurements to see what width and number of planks would fit in a given space.  Then I thought you tapered to that width.  But you seem to be saying that spiling is also a process of cutting the plank -- more or less shaping the top edge and using some method of transferring the curve above it to the plank being "spiled."  Does this contradict the rule of thumb that only the top edge of the plank should be tapered?

[russ]

Spiling is nothing more than matching the curve of the upper edge of the plank to the curve of the lower edge of the plank it will lay against. Once you match that curve, cut the curve into the plank. Now, you need to taper (reduce the width) of the plank on the its lower edge so that it will fit in the space allotted for it on the frames.

 

Spiling is transferring the curve to the upper edge of the plank. Tapering is reducing the width of the plank along its lower edge to fit it on the hull.

 

Russ

[fnick]

Hi Al

 

Spilling is best described (I think) by Chuck on this page: http://modelshipworldforum.com/ship-model-framing-and-planking-articles.php

 

Look at this article: Planking Tutorial - Lining Off a Hull. I am using it on my Le Mirage build. Try it with some card to get the idea. I found once I got my head around it it wasnt too difficult conceptually. Spilling doesnt contradict the rule of thumb that only the top edge of the plank should be tapered.

 

Hope this helps

 

Nick

[Captain Al]

Guys, thank you both for your explanations.  I've been experimenting with Starbucks swizzle sticks and I think I understand.  These sticks are easy to cut with an exacto knife.  I am wondering though how best to cut the curve into a 5mm wide piece of African Walnut.  I've had decent luck with the knife in straight tapers using a clamped on steel rule as a guide,  but cutting a curve is another thing entirely.  What methods or tools work best?  If the planks were wider I might think about using my dremel attached to a router table with a sanding drum.  Maybe a straight bit but that's scary.  But at 5mm, shaping down to even less, its hard to think how I'll control the feed.  I'm finding that while model building uses a lot of the same techniques as cabinetry, the size requires a completely different approach.

 

To add another problem to the mix, I have already laid  6 planks up from the keel without doing any spiling.  And I probably waited a plank or two to start tapering.  But it is what it is.  And what it is is a nice looking hull but with a slightly wavy effect.  Its been recommended that I take off some planks and start over.  Even though I know this is the best way to fix things, I am against this for a lot of reasons which would take too long to explain. So I'm trying to see if I can gradually reduce the wave by tapering and now spilling.  Is that possible or is it in there permanently without removing them?  I've also thought that a way to just stop it in its tracks so to speak is to leave a gap between the last (wavy) plank and the next one, filling it with a shaped plank later.  Its still pretty far under the hull that it wouldn't be too visible.  I'm working on Bounty and its a tough planking job and I don't expect it to end perfectly.  I'm trying to use this build (my first) as a learning experience and it sure has been.  But like I said, I'm aiming to finish it within my lifetime and plank removal doesn't square with that objective.  I am going to try to attach a photo to give you an idea of where I stand.  I want to again thank you for your time.  Each increment of additional knowledge helps me along. Well it seems my files are too big to upload.  I now have to learn how to take pictures that don't use up so much space.

[Captain Al]

Following on with this.  Did my wavy problem start because I was forcing each plank to conform its shape to the previous one?  I have been soaking the planks and they were easy enough to push into place and even twist 90 degrees to lay against the tail end of the false keel.  I think this is called edge bending.  In this case, was I wrong to do it even if it was possible?  Is it ever OK to edge bend instead of spilling (if I am using the term edge bending properly)?

[Captain Al]

I've learned a thing or two about my camera, so I think I can upload these photos.

[russ]

Al:

Edge bending is fine where you can do it. In some cases, edge bending is simply not possible, especially if the hull as a greater than normal amount of sheer (fore and aft curvature).

 

A lot depends on your personal goals and experience. I have planked hulls, spiling and tapering every plank. It was great fun and I received a good deal of personal satisfaction from it. I did not necessarily need to spile every plank, but once I learned how to do it, I never wanted to do it any other way.

 

Russ

[Captain Al]

I can see where it would or could be very satisfying and fun provided you are using the right tools and technique.  Where I'm at as far as possessing tools is that I have to use the exacto knife or the dremel.  There doesn't seem to be an in between.  And the exacto is very tiring (even with brand new blades) and the placement of my steel rule guide is very tricky and time consuming.  That's why I'm desperately seeking advice on the best tool to use. 

[russ]

I used a scalpel blade and an emory board when I planked my schooner model.

 

Russ

[Captain Al]

Russ, thanks so much for paying attention to me.  One more thing and I'll leave you be.  I went on line to get some scalpels and didn't realize there were so many sizes and shapes and brands.  Can you tell me what number scalpel you use mostly?  It looks like the number 11 is the same as a number 1 exacto blade (but probably sharper).  I was wondering if for purposes of cutting a straight line through 2mm wood a curved blade might be stronger and not break as easily.  But for curves, it would seem that the pointed tip #11 might work best.  As for brands, Amazon lists Swan Morton for very reasonable prices -- $25 for 100.  Do you know this brand?  Thanks again.

[russ]

I have some Swann Morton blades and they are very good. I reckon the number 11 blade will do the trick, but I do not use different blades for cutting straights or curves. I just use one blade for all of it. I think it is akin to a number 11. They come in small boxes with enough blades to keep you cutting for years. That is what I would recommend. Be careful though. These blades will hurt you if you do not pay attention.

 

When cutting planks, I begin with a first shallow pass over the line I am cutting and then make successive deeper passes until I cut through. I always leave a little meat on the piece and then sand it down afterwards.

 

Russ

[Captain Al]

Again, thanks Russ.  You've been a great help.  I haven't posted to my build log in months but you might be interested in the trials and tribulations of my Bounty by A.L.  I've been at it for 9 months now and will never give it up. 

[russ]

Just keep at it. I am sure it will look great when you get it completed. I always enjoy the process of building more than the finished model.

 

Russ

[Geek1945]

This video might help to visualize how spiling is done on an actual small boat:

 

Geek1945/Ed

[EdT]

Al,

 

You might find Part 52 of my 1:72 Young America build log useful.  It describes an easy process for dropping planks that results in fair lines and the right number of dropped strakes.  The process my be used on internal and external planking.

 

Also see Part 27 of my build log on the 1:96 POB version of Young America for the same process being applied externally.

 

I have found this method to be very effective at maintaining fair lines when planks are dropped.

 

Good Luck,

 

Ed

[ca.shipwright]

Al,

looking at your pictures, it appears that you are going to need stealers in the area between the last bulkhead and the sternpost. You can see that the planks are starting to curve up and this will produce problems as you progress.

[Cabbie]

Good Morning Capt'n Al

Difficult job planking these sorts of ships and I was lucky that I had a full size replica to copy.

 

https://www.flickr.com/photos/endeavourvoyages/albums/72157634081735926/with/9022926874/

 

Be careful with what I say I am not, by any means an expert on old sailing ships. more like an eggspurt.

 

I think your 1st paragraph is close to the mark, but planks should not be reduced to less than half the original size.

The planking rules did still apply, the joins still needed to run in the right line.

I tended to to whatever I needed to do to make the plank fit, without doing anything too drastic.

Have a look at how my endeavour planking finished.I haven't had any comments about whether it is strictly within rules.

 

http://modelshipworld.com/index.php/topic/11341-hmb-endeavour-1768-by-cabbie-artesania-latina-160-kit-fiddle/page-6

 

I didn't use steelers at the stern. I started out with wider planks at the keel which when tapered gave a natural curve upwards.

Planks were dropped under the wales as per the replica.

I Hope some of this helps

Cheers Chris

Edited January 21, 2017 by Cabbie

[AlfredoCampos]

Hi everyone. As this is an old post, not sure if anyone will notice, but I'll give it a try

 

A doubt on drop planks.

 

In one of the tutorial documents (Simple hull planking techniques for beginners by De Bakker and Brooker) there seem to be two different illustrations for drop planks.

 

On page 21, it seems 3 planks are running along, the middle one finishes in a 90º degree inwards angle and the above and below planks widden from there onwards.

On page 27 the method described by Al applies, two planks are running along, finish forming a 90º degree angle (45º each) where a new plank starts.

 

Thank you!

[druxey]

There are two methods, as you describe, either 3 to 2 or 2 to 1, depending on the degree of reduction (or increase) in width required in the situation.