Thukydides, I think I agree with David. It's the curvature, not the point at which the wales meet the stem. I think this is more or less how it should look and what David means:

As the wales are created in the two dimensional sheer plan, they don't gain a lot of height for their run close to the stem, if that makes sense.

Measure against the plans though, that's a better standart than what looks right.

You are good if the height of the curve from abreast the foremast to the stem at various points matches the draught exactly.

So after a bunch more looking and comparing to the plans I better understand what @druxey and @Arthur Goulart were saying. I might be able to fix it with small adjustments, but I think the better path is just to rip all of the planks off and restart from marking the wales once again. So it may be a bit of time before and update as I need to break out the isopropyl and remeasure everything.

I will update once I have some progress to show.

It's always lovely to see that kind of commitment to getting things just right!

It’s going to be a lovely design.

12 hours ago, Arthur Goulart said:

It's always lovely to see that kind of commitment to getting things just right!

I almost didn't go back, but then I knew I would regret it. I suspect as always the redo will go faster than the first version.

Thanks for your feedback I really do appreciate that you take the time to help me improve the model.

And just like that all the planks are off again. One advantage of using wood glue is isopropyl takes it all off relatively painlessly.

Back to measuring...

Painful, but you'll be glad!

I have a lot or respect for modelers who pull things apart and start over with something that isn't quite right. When I started planking my Cheerful it was taking several hours to shape and attach each plank. I realized my plank run was going off course, but didn't want to pull the few planks off since I had just spent so much time shaping them. It nagged at me, so the next day's project was pulling them off. It set a standard for myself on knowing when that nagging little voice is telling me something isn't quite right, to suck it up and make the corrections necessary.

Erik

Log #9 - Re-Doing the Wales Part I

Following the my decision to remove the wales and start over, I began the process with redrawing the waterline. There was no issue with the previous waterline as it turned out, but just to be sure I decided to redo it. However, when it came to the question of how to proceed with the wales, things were a bit more difficult.

I discovered two problems that made simply measuring the height off of the plans problematic.

1. There is a minor bend in my build board. This doesn’t really throw things off much, but it makes getting a consistent measurement relative to it difficult.

2. Somewhere along the line I introduced a few mm of error into the height of my model relative to the plans. We are only talking about a few mm, but the error is not consistent accross the whole model.

These two problems combined introduce a few mm of error, which in general is not a huge deal, but will make a difference if I am looking to get a smooth run of the wales.

So to solve this problem I decided to use the vertical distance between the waterline and the wales as my reference. This however introduced a further issue. The waterline on the Sphinx class is not parallell to the keel. There is a slight keel drag. So I had to improvise using the following method:

1. I measured the vertical distance on a bulkhead between the waterline and the bottom of the wales from the plans.

2. I measured the vertical distance from the build board to the waterline at the same point using my callipers held upright against a mini square (see the below picture). Note this is not really measuring the height as I am technically measuring from the bottom of the callipers, but as I will use the same method in step 3 it doesn’t matter.

3. I added the measured height of the waterline to the measured vertical distance from the plans obtained in step 1 together and then set the callipers to that height. I used this to mark the location of the wales on that bulkhead.

4. The same measurement in step 3 was transferred to the opposite side of the vessel.

I thought I would share the results before I start placing planks again in case anyone sees any issues. The run appears to look smooth and as you can see it is much flatter with a slight downward bend at the bow.

And just for comparison here is what the line looks like at the bow compared with what I had previously planked.

See my comments on the 'other' site!

Looking proper to me! The difference to the previous version is noticeable.

Log #10 - More Structural Problems

So now we embark on part 2 of the saga of how lack of care in the early stages can lead to problems later. Anyone wanting to make a first attempt at scratch building, make sure you take an unreasonable amount of care to make sure everything is straight and square when you are building the structure.

If you remember in log 9 I mentioned how there was a maybe 2mm measurement error near the middle of the build board. Well following @druxey’s advice I decided to try and fix the build board only to discover that the problem was with the model.

You can clearly see the problem at point A (I put the model in front of the window to help it to be clearly seen). There is an upward bend in the keel and the size of that gap roughly accounts for the measurement error I have been having at that point of the model (2mm).

The bend appears to have two main components to it. The area around A is bent upward, and the area around B is bent downward. The problem is not really visible if you are not looking carefully at the gap in the build board, but if you hold a ruler to the keel it can be clearly seen. There is also a slight issue at the bow, but I don’t really see an option for fixing it and it is relatively minor compared to the other two.

The bigger problem is that this creates an issue for the waterline and the wales. The error is not huge, but in the context of the placement of the wales it is significant. I am at somewhat of a loss as to what to do about this and am looking for suggestions for either how I can fix it or how I can work around the problem. Two main ideas come to mind, but they are both a bit risky in different ways:

1. Leave the problem alone and just adjust the curve of the wales at the stern to help compensate for this. This has the advantage of not having to remake structural issues, but I am not sure how many future problems I am making for myself. I should be able to adjust the run of the wales to get them to look right at the stern (the biggest problem caused by this issue), but the positioning will be slightly off and so the spacing say between the gun ports and the wales will still be impacted.

2. Make a risky structural change. Remove all the supports from C and try to maybe cut a small slit in the center bulkhead to try and cause it to bend together to correct the center issue. I could also try to cut a small slit along the bulkhead at B to try and bend it up at that end as well. I am not sure how well these will work and they are certainly risky as I could easily damage the keel and ruin the model. In addition modifications at point C run the risk of ruining the run of the ports as essentially I will be correcting a gradual problem at a single point.

I am interested in how viable any of you think either these options are and/or any other suggestions you have for what I might do.

Wich kind of plywood did you use? It looks that the problem comes from joint of longitudinal bulkhead. If there if some space int the glueing joint you could get this result.

But hogging on a normal ship is quite normal ...

8 minutes ago, AnobiumPunctatum said:

Wich kind of plywood did you use? It looks that the problem comes from joint of longitudinal bulkhead. If there if some space int the glueing joint you could get this result.

But hogging on a normal ship is quite normal ...

Yes there is somewhat of an irony that I have a hogging problem :).

I used birch plywood from my local hardware store. You may be right, but I am not sure how I didn’t notice this when I was putting it together. I am wondering if it was a combination of that and also too much pressure on the upper parts of the bulkheads as I assembled the structure that slowly exacerbated the problem. The issue is there also appears to be an issue in area B so it is hard to say exactly what happened.

One approach might be to add a bolt through the board and keel at the point of maximum deflection to pull the keel down level, but only if you can easily push things into alignment. I suspect this may be too optimistic!

If it will not go down using reasonable hand pressure, then a bolt will not work. You will need to take more extreme measures. You will have to saw through the longitudinals in at least two places to relieve stresses, insert thin wedges and glue them in. However, don't overdo this, or you will have a problem in the opposite direction!

Good luck with making the correction, but you will be glad later that you took care of it now.

As a footnote; I always drill and bolt my models down on the board as soon as the keel is made, through the points where the mounting pedestals will eventually go.

1 hour ago, Thukydides said:

am looking for suggestions for either how I can fix it

You might try using two hot air guns, one on each side of the keelson, and a cargo tie down strap. Measure the widest point of the airgap and jot that down. Run the strap over the top of your keelson, at the center of the hog, and hook the ends to the edges of your table. Turn on the hot air guns and tighten the strap until your keel is flat on the table and let it stay under tension and heat for as long as you can stand it, then turn off the air guns but leave the strap tight until the keelson has thoroughly cooled. Release the strap and measure the airgap again. If it is smaller, this 'should' work. The new measurement will equal the approximate amount of 'spring back' to expect. Using 1/8" / 3mm thick spacers, placed at the beginning and the end of the hogging, continue to heat/cool the keelson, adding another 1/8" spacer and moving your strap to a new location, within the hog, after each hot/cool cycle until your hog finally goes away. Once straight, thoroughly seal the bottom half of the keelson sides 'ONLY' with thin shellac! Seal it until the plywood has absorbed all the shellac it can and has become glossy. This, in theory, should swell the wood grain, at the bottom half of the keelson, making it want to expand/smile. In addition... while heating and tightening the strap, you will also need more vertical supports to hold the keelson at 90 degrees to your build board and prevent it from twisting. This might appear to be a lot of work, but it really isn't. Once you have your keel vertically supported and all of your tools ready, it shouldn't take more than a couple of hours' time or so to straighten things out. You'll know if it's going to work, or not, after the first hot/cool cycle.

To be honest, with all the described problems, I would live with the hogging or redo the work. I don't think that you can solve the problem without destroying much of your work.

Birch plywood should not the problem. I use it quite often. I know that beech plywood can make such problems. It react really sensitive on different humidity.

If you redo the construction, I would change the design:

• Use of a vertical construction joint on the hull

• Use of a horizontal plate for stabilization

Have a look at a paper model from shipyard for example. The construction method is really good and gives a stable hull. You can use it also with wood.

How will you finish her? One solution might be adding a strip of wood and sanding the keel flat. It wouldn't be very elegant, but, if you're planning on having copper over it, it would be hidden.

On 8/23/2026 at 9:54 AM, Arthur Goulart said:

How will you finish her? One solution might be adding a strip of wood and sanding the keel flat. It wouldn't be very elegant, but, if you're planning on having copper over it, it would be hidden.

I am actually planning to leave the bottom uncovered so this unfortunately is not really an option.

Just by way of an update I have started work on the fix using a method similar to what David suggested. It does seem to be working and I will post more details when I have something to show.

Thanks again to everyone for all your suggestions.