21 ft Yawl Longboat for a Sixth Rate by vaddoc - FINISHED - Scale 1:10 - Plans from the National Maritime Museum

[vaddoc]

Gary and Brian, many thanks!

I am not sure if I ve mentioned it but I am actually thinking for this boat not to use tree nails to hold things together, like I did with the Deben. I d like to try brass wire 0,7 or 0.8 mm, threaded. There will be no glue holding the planks, just the threads. The planks will be initially fastened to the temporary frames with 0.6 or 0.65 mm brass pins, then removed. The biggest problem will be lining up the plank overlap (2.5 mm) and the frame inside (4 mm sided) - for all 2000 or so rivets. I ll do a bit of testing when time permits and will post the results.

[vaddoc]

Life went a bit into overdrive but still I managed to do a bit of work.

First, I glued the cant half frames with thickened epoxy using the jig to hold them in place. They came out fine but I forgot to take pictures.

 

Then I made the decision to use the solid wood keel and trimmed it to shape-I think it will be fine.

I then made the sternpost and the knee and I fiddled a bit with it, to make sure it sits flush with both the keel and sternpost.

 

Then I made the stem. Initially I wanted to laminate it but I decided to make it from overlapping 4 mm thick pieces. Not historically accurate but certainly faster and simpler.

Then I worked on the jig. It needs to be completely flat and it seems that the boat will need to be built upside down. We ll see

I also made a brilliant purchase, a 1 m steel ruler. I really don't know how I managed so far without it! Lovely thing

Then I assembled everything together and of course they don't fit. The frames seem ok but the sternpost and stem don't have any reference points so they are not in the right place and need to be further trimmed.

I checked the bevels once more now that most pieces are in place and it really looks ok

Then I hit a snug. In the plans the Transon needs to be 5 mm thick but I do not have 5 mm think pear sheets but I do have 4. Only solution to shim the sternpost-I think it will be fine.

 

There are still many other tasks to be completed. Somehow I need to trim and align everything, secure the frames to a near vertical position and cut the rabet on the sternpost and keel-this last job will be difficult.

Then the sternpost and knee will need to be securely attached to the keel and the whole thing somehow to the frames. I need to make the transom and fit it to the sternpost squarely.

Baby steps...

[Bedford]

In my "Miss Caroline" model build I used small brass nails to secure the keelson to the moulds. I also used them to secure the strakes as I went, the resultant holes are tiny and easily filled with a little wood filler. In my case the floor boards cover most of the holes in the lower hull anyway and I would assume the same would apply in your case but they are so small you have to look for them to see even the ones in plain view up the sides of the hull. My hull is more spartan than yours will be too so they'll disappear easily.

 

[vaddoc]

Thanks Bedford, indeed this is an option. I have several sizes brass or steel pins from 0.5 mm to 1 mm or I could use micro screws. The planks could be glued or tree nailed to the ribs. I just would like to investigate whether threaded brass wire alone (I think 0.8 mm) could be used. There would be 10 threads in each 2 mm plank and frame/rib which should be plenty strong. No holes to fill, just the wire to cut flush. The challenge would be to re use all the holes, this means not a single rogue one. Statistically this is impossible as there would be 2000 holes or so but I ll give it a go.

I am thinking of using initially 0.5 mm pilot holes with 0.5 mm steel pins to go through the lapstrake overlap and into the temporary frame. The pins would later be removed, the hole opened up to 0.6 or 0.7 mm going through the permanent rib at the same time and all secured with the threaded wire. Plenty to go wrong!

 

1mm wire behaves fine but 0.7 mm tends to twist along its axis almost to braking point. I hope 0.8 mm will be safer while still acceptable in scale.

 

Regards

Vaddoc

[Bedford]

Yeah that's an interesting concept, you've set yourself another challenge. It will be interesting to watch it take shape and one to remember I think

[vaddoc]

A bit more work done and time for another update.

The boat is progressing very slowly. I cannot work as often as I would like and It takes me a while to remember where I left things, it is a pretty complex boat. Also building (kind of) the Chapelle's boat at the same time is not helping much...Still, some real progress made today.

First of all, I printed out the patterns for the bow and stern to check how close to the CAD designs the wood pieces actually are. Happily, they are very close.

 

I then finished the transom. I thought of leaving wood on for a safety margin, as I think is standard practice in actual boat building, however it is much easier to sand the transom now.

I then glued and screwed the sternpost to the keel. I first drilled 0.7 mm holes to the keel, then taped the sternpost to the keel and hand drilled the rest of the way in the sternpost. Then I counterdrilled the holes in the keel to accept the head of the screw and screwed the 2 pieces together, with PVA in between. The joint is rock solid, the holes will be filled later on.

The procedure was repeated for the stem but here I hit a snug: The keel will need to be notched for the rabet and might hit the screws if placed laterally. So I drilled new holes, this time at the midline. The stem looks like Swiss cheese but I ll fill the holes later on.

Then, I made again the hog or apron as the previous piece had some dents. Now, I had to figure out a way to make sure the frames are correctly placed/spaced but also that the keel is secured to the frames but in a non-permanent way, so that the frames can be removed later and replaced with ribs. The way to do this will be to screw wood pieces to the apron and glue the frames to these pieces. Then unscrew these when it is time to remove the frames. So here it goes:

 

The previous apron was cut up and wood inserts were made to go in between the rib spaces. The sides that will be epoxied to the frames were marked. Then these were lightly glued to the paper template of the apron

Now, the keel has a slight bend laterally so i used some clamps to bring it in line with the apron..It straightened a lot

Next the filler pieces were removed, the paper template removed from the apron which was then sanded clean. Then the pieces were screwed on again and the assemble glued and screwed on the keel

 

This did not go as well as I would like because the apron, being very wide and only 2 mm thick, cupped from the liberal use of PVA. I do not think this will be a problem as it could uncup when dry but either way, a lot of it will be chiselled away and it will be invisible under the floors.

 

Regards

Vaddoc

[druxey]

Whenever glueing a thin wood piece using a glue with water content, dampen the opposite side first to counteract the tendency to bow or cup.

[vaddoc]

42 minutes ago, druxey said:

dampen the opposite side

Couldn't do this Druxey as it was all covered up by the filler pieces. Maybe it will sort it self out when dry

[vaddoc]

Some more progress, time for another update. Things are getting now a bit complex, I ll try to explain as best I can

I have been able to work on and off on the boat so far but this is now becoming increasingly difficult, for the next few months, I ll be working 6 (and a bit) days a week so I expect things to slow down to snail pace.

 

First of all, I decided to lighten the frames significantly. After the planking is completed, I will need to install steam bend ribs in between the frames and simply there will not be enough space for my hand to fit in. So, I cut large pieces off but left two cross beams, one at the base and one mid-frame that will be easy to cut off later on with the dremel wheel. The frames are still very solid.

Next was the big job of cutting the rabet and shaping the hog. Now, this was properly difficult.

It is impossible to follow the lines in the printed templates due to the large tolerances of my work but I am not too far off either. One interesting thing though is that the boat seems to have corrected my draft error. In my plans I had made the rabet a curved line but now it seems to have flattened.

 

I started cutting the rabet mid ships where the planks meet the keel almost vertically, still however it made a difference in the fit.

First photo is fit without rabet, second with. Difficult to capture but it is better.

I then took a break to clean and sand the transom as it will soon need to be fitted. Lovely solid piece of pear wood.

Then I thought I wood install the sternpost knee. This is screwed and glued.

In the photo above I have also added some wood next to the knee, cutting notches for the two aft frames. Let me explain why:

 

It is very important for the garboard plank to be fully supported along its bottom edge. The rabet is not enough, this is why the hog is needed to add more supporting timber. However, I made two mistakes.

One is that I did not make it long enough. It should extend from the sternpost to the stem so that after bevelling, it will support the plank for all its length. So, I am adding wood to the stern and will do the same for a short distance at the bow.

Second mistake is that I did not make it thick enough. Putting the bevels, it gets very thin. So the pieces that I had screwed on top of the keel, thinking they will be just temporary and used to hold the frames in position will need to be permanent. These will also help with the ribs later on as their position on the keel will be already defined.

I have replaced the pieces that will not be used for gluing the frames, the ones that will be sacrificed are marked with an X, these will be removed with the frames after planking and replaced with nice wood without screw holes.

Then I cut the rabet. Forget about plans! It was done with just eyeballing the angles and using small pieces of wood. 

This is where more wood needs to be added to support the gardboard up to the stem edge.

I tried a piece of 2 mm cardboard to see how the planking would go. It looks ok!

Then with a big push I finished the rabet. A bit more material needs to be removed from the sternpost

Now, another task was actually to reshape and sharpen my 4 mm chisel. So far I have been sharpening it free hand but now the bevel is so curved that it affects its function. Now, a few years ago I had made a simple honing guide with scrap wood, metal and bearings. I dug it out and used it. Perfect results! The next photos show the jig and how curved the chisel was. Since I ve honed it to a mirror finish

There is also another thing that is troubling me, the wood I chose for the planking. I chose 2 mm beech. For the Deben I had used 2 mm maple which was perfect and very pleasant to work with, easy to cut, easy to shape and bend. However, the beech I received is much harder and resists bending plus it is 2,2 mm instead of 2. The planks will be cut with a knife so I expect a big struggle. I hope at least that the wood will respond well to steam bending (it should really being beech).

 

As Brexit is getting much closer I put in another big timber order from Germany. I will have enough lovely wood to last me for years, pear, beech and cherry. I hope it will not rot or cup with the huge variations in temperature and humidity we have hear in Britain.

 

Regards

Vaddoc

 

[G.L.]

Vaddoc, Very nice work, the cutting of te keel rabbet!

[FriedClams]

Very nice progress Vaddoc.  And I like your chisel honing jig - very cool.

 

Gary

[mbp521]

Very tedious work, but she’s looking great. Love the chisel jig as well, perfect way to keep an even edge. Pretty ingenious. 
 

-Brian

[Vladimir_Wairoa]

always pleasure to look here vaddoc. new boat is being raised up to shape. hoorah! thanks fo sharing the process as well, it is really helpful. very nice, happy continuation.  Vlad. i can see familiar chisel name :)) and jig is no 1! 

[vaddoc]

Dear all, many thanks for your comments and likes. Unfortunately It took me a while to come back to my log as life has gone into hyperdrive again.

 

All the frames are now in place and strengthened with pieces of wood. The boat is ready to be planked! However, I will temporarily hold the build and concentrate bringing the Launch to the same point. I think it will be interesting, these two boats are completely different in shape and I am curious how the planking arrangement will compare.

 

A few final photos, the log will continue with the (clinker) planking, provided I will manage to get the 2 mm beech planks to bend.

[Wintergreen]

Just read through this build log of yours.

Quite a bit of thought has gone in to the build already with all the discussion of drafting in CAD and so on. I started a rather hefty project several years back but since I was not up for the task then the project stalled. But I still have all the work saved, so maybe one day.

 

I like your serious approach to the drafting and building. It's a shame though that you can't mill your on lumber. A lot of challenges there I sense. 

Keep it up!

[vaddoc]

Dear all

 

With the hull of the fishing launch completed (but still not finished), I decided to start working on the Yawl.

 

The initial intention was to build two hulls back to back, one carvel and the other lapstrake, as a learning exercise as well as building two boats I like. The two hulls are very different and my initial impression is that planking the Yawl will be much more difficult. 

The first challenge came when I tried to deploy a baten. My usual 2 x 4 mm strip cannot negotiate the curve at the bow, it will break. How do you plank a boat without batens? I tried a slightly wider one-no go.

I used a 2 x 2 mm pear strip that looked bendy and starting playing with the hull. My initial intention was to divide the hull into three areas. To do this, 2 lines are needed. One going through the point where the transom and sternpost join, and another one halfway from that point to the sheer.

 

In lapstrake, the planks should have equal widths but to the eye, only the planks at the sides being vertical will show their true width. The planks bellow the turn of the bilge being at an angle will appear more narrow. So, in reality, only the planks in each zone need to have the same width.

 

I tried to eyeball the run of the strip, to make sure it is fair but that was impossible. A square sectioned baten will happily bend in all directions. Again, the very curved bow made it very difficult to arrange a fair run. I tried many times but afterwards, eyeballing the hull, it was obviously wrong.

I did manage though to define the sheer using my CAD markings-I hope these are accurate.

However, all of the above attempts were wrong. The run of the 2 dividing lines is far from fair-it is all over the place. It is impossible to do this without a baten.

 

So I use two maple strips, 1x8 mm (or something like that) as batens, They are very straight, very bendy and do not permanently deform and of course they will not tolerate any edge bending.

 

After many failed attempts, I think I got my 3 zones kind of close. Now, the following  photos show how difficult this hull is and how the bow messes up the perspective.

In the first photo, the lower baten seems wrong and the one near the sheer appears fair. In the second photo, it is the other way around. In the third photo, both look ok.

I marked the lines and removed the batens

This would be a very difficult boat to plank as carvel. Lapstrake, even more.

I have no idea what kind of spilling will be needed. Judging by the lift of the batens though, I expect the planks will have significant curves. Considering how long they will be, I think all of the planks, except perhaps the garboard, will need scarfing.

I had decided on this boat to hold all planks with threaded brass wire. This would mean drilling 0.5 mm holes, using brass pins to hold the planks to the temporary frames, then re-drill to 0.6 mm when the steam bend frames are installed and screwing everything together.

 

Have I bitten more than I can chew? Quite possibly!

 

[Dowmer]

Vaddoc, 

you have a couple options for planking (spilling or edge bending), and the yawl really isn’t that difficult to plank.  Chuck Passaro’s tutorials are invaluable and I highly recommend you read through his planking of the Longboat Medway, Cheerful and his Winchelsea. His planking is perfection. Although carvel planking, the lining out and edge bending should be the same. 
 

here is a link to some of his videos.  But his build threads are a treasure trove. 
Chucks planking videos

Edited May 30, 2021 by Dowmer

[druxey]

Use threads instead of battens with a  spot of PVA on the frames. To adjust them,  wet your finger and roll the thread up or down the frames as required,

[Bedford]

The following is intended only as food for thought.

 

Should all the planks (strakes) be the same width or should they appear to be the same width?

 

Granted my full size lapstrake boat is epoxied ply construction and the strakes appear to have similar width relevant to where you look along the hull but the strakes themselves are wildly different and some really strange shapes are used to achieve this.

 

This is demonstrated by the second photo in your post above, the midway batten looks "wrong" because of the curves but look at it from a level side view and it looks perfectly fair. The point is, you can look at the batten from any angle to ensure it is fair with the flow of the hull but the only angle you can view from to decide if it's following the correct line is a level side view.

 

I've included a pic of some of the strakes for my boat

Edited May 31, 2021 by Bedford

[vaddoc]

Many thanks for your likes and comments!

 

10 hours ago, Dowmer said:

Chuck Passaro’s tutorials

Dowmer, I ll be using 2 mm thick planks, probably 8 to 12 mm wide. Unfortunately, the only edge bending it will tolerate is a little nudge to fit into place! However, I have many lovely maple strips which I d love to use, I ll give it a try and see whether Chuck's method will work.

 

10 hours ago, druxey said:

wet your finger and roll the thread up or down the frames as required,

Thanks for the tip Druxey. In the past I had used very thick black fishing line. The problem is that due to the shape of the bow, the perspective is easily lost and I cannot eyeball a fair shape. This is why I need a very wide baten, to make sure there is no edge bending and the lines are fair. But even with this, bending the baten around the curve at the bow, pulls the baten up midships. A very stubborn hull.

 

6 hours ago, Bedford said:

I've included a pic of some of the strakes for my boat

 

Bedford, you answered a few queries I had but now I have another for you.

Planking the launch, I had noticed that at the bow some planks had a funny S shape. Initially I tried to simplify it but then I realised that this would be wrong and I had to trust my markings. The bow of the launch is very sharp, so probably this is why this S shape was less pronounced-it is much more visible in your boat and I expect even more on the yawl.

 

Now, the planks in your photo are half planks-or plank thirds. I assume many adjacent planks would need scarfing. Here is the question: Does it matter if the scarfing is done at the same point mid ships or would builders spread the joints at different frames?

 

Wonderful plywood by the way!

 

Regards

Vaddoc

[Bedford]

I would think the almost bluff bow on this boat will definitely have some "S" form going on and much more than my boat so yes, trust the lines.

 

As for the scarf joints, none of them line up exactly. They are fairly close but the scarfs run away in opposite directions to spread them out. In my case there are two pieces per strake. Having said that, mine is a glued lapstrake boat and the epoxy bonds are very strong. I'd imagine on a traditionally planked boat they would be scarfed in a much more staggered manner and cross a frame.

[Wintergreen]

Vaddoc, seems like you're in for a challenge here 😉

About scarfing, on a lapstrake boat of any size I'd assume every strake is always two pieces. It would be really hard to get a watertight fit in stem and stern at the same time with one full length strake. And since the strakes are in two (or more) pieces the scarfs are always staggered. Probably a couple of feet apart. (maybe that was not the question though).

Trust your eyes and not so much the mathematics in the laying out.

 

[vaddoc]

Thanks Hakan, that was indeed the question

 

1 hour ago, Wintergreen said:

It would be really hard to get a watertight fit in stem and stern at the same time with one full length strake.

Now I ve never thought about it but I think you are right, unless the plank is perfectly cut, with time it will warp back and no rivet will hold it. Much more difficult to perfectly cut a very long plank than a short one.

[vaddoc]

Dear friends

 

Due to increasing life commitments it's been almost a month since my last post. Unfortunately, I also did not have any time and more importantly peace of mind to visit the various very interesting logs I 've been following - I will try and catch up. However, I found some scraps of time to visit the shipyard and made a bit of progress.

 

 In the last post, I had divided the hull to three zones. Excluding the very curved bow, this hull seems to be much easier to plan that the Launch. I simply used the planking fan diagram to divide the zones into plank widths at every station. I used a baten to figure out the plan ends at the bow and stern. I have decided to scarf the planks so I do not care how much spilling will be needed and how curved they 'll end up to be. The final fairing of the planks will be done during the actual planking but I hope my lines are not far off.

It is very difficult to capture the run of the planks right side up, due to the size of the boat but they look ok

But now it is clear that this boat will be very difficult to do lapstrake. I am concerned that this curved bow will cost me my sanity. I wonder whether it would be better to do a carvel planking and leave the lapstrake for a future boat with a more friendly bow. Decisions-decisions...

 

For now, I started making the first template, for the garboard plank. Initially I thought to do it in 3 pieces but then realised it makes no sense to have so many scarfs - one is plenty, giving a length of 3 to 3.5 m per plank. The last photo shows the pieces for the aft segment of the garboard-they still need to be connected.

I have the feeling that the garboard should be a bit wider but I am not going back, it will be fine. Also, I need to figure out a way to scarf the planks. It needs to be reproducible and reasonably easy.

Also, for this boat I will sand the planks to shape, and will put more effort to have minimal gaps.

 

Regards

Vaddoc

[mtaylor]

No apologies needed,  Vaddoc.  Real life comes first.   Looking good so far.  

[Bedford]

Hand scarfing is pretty easy. The norm for the length of the joint is 8 or 12 to one. This may be difficult with planks this thin so you may need to come up with a smaller ratio that's easier to cut.

 

The process is simple:-

1. Measure the length of scarf on the first plank and draw a line square to the plank
2. With the next piece, lay it as it will be joined to the first then flip it lengthwise so you get the correct orientation on the cut and mark as per the first
3. Lay the pieces down on a work surface with a hard edge so that the lower piece is exactly on that edge
4. Lay the second piece on top with its edge right on the line on the lower piece and clamp it all down
5. Use a small and very sharp plane to cut the scarf using the table edge and the line on each plank as datum points

[vaddoc]

Many thanks to all for your comments and likes!

Bedford, that was great. Unfortunately I do not own a quality plane that can reliably do the job. However, your suggestions were very helpful and I think I did find a solution.

 

Also, I decided that the planking will be carvel. I will in the future make a large scale lapstrake boat but I will choose an easier boat. It will be lots of fun but needs to wait.

 

I first made the port garboard in two halves. It took very many tries, I kept getting it wrong but finally I got it right. The planks are sanded to shape so the edges are much smoother compared to the Launch, which were cut with a knife.

This is the overlap for the scarf joint

 

The twist in the garboard is significant, almost 90 degrees. Planks will easily take a bend but will resist a lot to be twisted. Note the gap between plank and keel-it disappears with the plank in place.

Another area that needed attention was the stem. The edges have to be trimmed to accept the plank ends. After planking, the excess plank material will be trimmed off so that the false stem will sit flush. Or so is the plan...

Next, I tackled the scarfing. After a bid of thinking and testing, taking on board Bedford's suggestions, I find a solution. Since the planks are 2 mm thick, I went for a 25 mm scarf joint. Basically, I just used the belt sander bellow to create the bevels. This worked fine with no dramas. The edges will stand a bit proud but nothing a bit of sanding will not fix. I ll probably try and thin the edges a bit more.

 

 

Now, much more care has gone into this boat, compared to the Launch. The CAD drawings are much more accurate, the frames were cut with much greater care and generally, it was put together better. With this in mind, I decided to make a set of identical garboard halves for the starboard side. Test fitting: They fit!

 

So now I have both garboards. They need to be steamed and secured into place, this will also make the whole structure much more rigid.

 

Another issue that needs to be dealt with is how to secure the planks to the frames. I was thinking of using threaded brass wire but now I am not so sure. This was the plan for the lapstrake. With carvel planking, sanding of the hull will be needed and the brass will complicate things. Maybe tree nails will be a better choice.

 

Regards

Vaddoc

 

[Mark Pearse]

Hi Vaddoc

 

It's exciting to see the planking commence. I hope you get some more time to build in the near future.

 

Are you planning to set up any battens or thread to sight the planking lines?

 

[vaddoc]

On 7/18/2021 at 11:28 PM, Mark Pearse said:

Are you planning to set up any battens or thread to sight the planking lines

All done Mark! But the lines are on the other side of the boat. The final fairing will be done while cutting the actual planks

 

Today I nipped over to the shipyard, just for a few minutes. I put the planks to the steamer and then straight on the boat. Beech responds great to steaming, the planks immediately twisted to shape.

 

Actually, the garboards look reasonable

The problem with planking without a complete stem is that it is difficult to get the planks to end up at the same level on both sides. The excess wood at the plank edges will be trimmed away when the false stem is installed.

The scarf joint needs a bit of tinkering. Or maybe I just need to push the half a bit forward.

 

Best wishes to all

 

Vaddoc

[Bedford]

With the scarf joints, if anything, the overlap you have on the exterior is the best place to have it. Easy to sand down.

 

As for the strakes all being dead even at the stem, that isn't always the case. The good shipwright will strive to achieve it but there's no structural reason for it and I'd imagine that work boats built quickly and to a cost would be the most likely to have some discrepancy there.