This week I ordered some lime planks for the hull from Cornwall Model Boats - 6mmx1mm and 6mmx0.5mm.
I decided on lime because I read on another build blog somewhere that lime was very flexible, not too expensive and I didn't really care what the colour was because the hull will be painted anyway.
I decided to go with 1mm and 0.5mm thickness to allow for double planking and still come out with a hull that is roughly the same thickness of the 1/16" ply from the plan.
Initially I thought I could run the 1mm planks longitudinally along the hull, but that idea didn't survive a dry fitting attempt, so I fell back to something at roughly 45 degrees. It also became clear after placing a few planks that just using the bulkheads wouldn't be enough so I started to add an extra vertical rib in between the bulkheads for extra support.
I was also toying with the idea of getting some planking clamps that I'd seen on Amazon. I forgot to order them by the time the planks arrived though, and after a bit of experimentation I found that crocodile clips with a paper clip inserted into the back do the job pretty well.
The last picture is one side of this weekends progress so I could be at this for a while. I think I'll be able to go a bit quicker now I've worked out the clamping, ribs and glue setting time, but I'm in no real rush.
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This week I ordered some lime planks for the hull from Cornwall Model Boats - 6mmx1mm and 6mmx0.5mm.
I decided on lime because I read on another build blog somewhere that lime was very flexible, not too expensive and I didn't really care what the colour was because the hull will be painted anyway.
I decided to go with 1mm and 0.5mm thickness to allow for double planking and still come out with a hull that is roughly the same thickness of the 1/16" ply from the plan.
Initially I thought I could run the 1mm planks longitudinally along the hull, but that idea didn't survive a dry fitting attempt, so I fell back to something at roughly 45 degrees. It also became clear after placing a few planks that just using the bulkheads wouldn't be enough so I started to add an extra vertical rib in between the bulkheads for extra support.
I was also toying with the idea of getting some planking clamps that I'd seen on Amazon. I forgot to order them by the time the planks arrived though, and after a bit of experimentation I found that crocodile clips with a paper clip inserted into the back do the job pretty well.
The last picture is one side of this weekends progress so I could be at this for a while. I think I'll be able to go a bit quicker now I've worked out the clamping, ribs and glue setting time, but I'm in no real rush.
One thing about diagonal planking - you do seem to be going on forevermore putting planks on - getting no where and all of a sudden it is done.
I myself have diagonally planked several hulls; even the one you are building the RTTL hull - and I tend to add stringers from bow to stern - maybe 2 on the side and 2 on the top - of each side of the hull. This serves 3 purposes; 1 it aides a bit more strength to the hull, 2 you can follow the true shape of the hull as in concave of the bottom and on the sides, 3 it gives you an extra place to clamp your planks to.
If you have a look at my photographs in my profile, you will see the RTTL model which I built there.
Are you making it twin prop? or, some of these vessels were triple props if you want a bit more excitement.
Good luck with the planking and the model. It is a lovely model to sail.
Hi John, Yes I'm finding the going slow. 6mm planks don't cover a hell of a lot!
I did think of doing stringers instead of ribs, but in the end went with ribs.
That could be a mistake, but if so it won't be my first and hopefully it won't be terminal.
As John mentioned in his comment on my previous post, planking the hull is a long process.
I've been doing a bit here and a bit there all week and still I'm not quite half way along the hull sides above the chine with the first layer.
I did remove the hull from the jig and reset it so that the keel is clear for planking but that still seems a long way off...
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As John mentioned in his comment on my previous post, planking the hull is a long process.
I've been doing a bit here and a bit there all week and still I'm not quite half way along the hull sides above the chine with the first layer.
I did remove the hull from the jig and reset it so that the keel is clear for planking but that still seems a long way off...
I've just started planking the hull on my Fairey Fisherman, as you say it's not for the impatient and will be slow going. First time using this method for me and enjoying it.
I ordered 1/32" ply and 1.5mm bass to give me options but a test with the bass had it break as I turned it round the bilge. 1mm may have been Ok but the ply is fine, even though I'm having to cut the planks. I'm diagonal planking at around 30 deg so that the planks don't distort too much at the turn. I'd planned on diagonal planking from the start so included additional stringers.
I'm doing the little Faun as well but am longitudinally planking that. Choice is between 3mm balsa or the 1.5mm bass with the latter being the probable choice, which I'm just about to start.
It's been a few weeks since I posted an update, but planking is slow and there just wasn't anything of interest to say.
At last the first layer of planks on the hull sides is complete.
I've also trimmed the planks and shaped the keel to the bulkhead levels to allow the bottom planks to be done next.
The bow area needed some experimentation to keep the planks clamped down, but other than that it was just a question of keeping going until it's done.
I continued with ribs rather than the stringers that other people have used, but overall I'm happy with the result so far.
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It's been a few weeks since I posted an update, but planking is slow and there just wasn't anything of interest to say.
At last the first layer of planks on the hull sides is complete.
I've also trimmed the planks and shaped the keel to the bulkhead levels to allow the bottom planks to be done next.
The bow area needed some experimentation to keep the planks clamped down, but other than that it was just a question of keeping going until it's done.
I continued with ribs rather than the stringers that other people have used, but overall I'm happy with the result so far.
Life has gotten in the way a bit recently and hull planking is a slow process, but I've continued to plug away at the first layer of hull planking and finally finished on Friday night.
Using extra ribs but no stringers made more of a difference on the bottom and from certain angles things do look more lumpy than I'd like, but I'll probably be able to fix it up with some filler since this is just the first of two layers.
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Life has gotten in the way a bit recently and hull planking is a slow process, but I've continued to plug away at the first layer of hull planking and finally finished on Friday night.
Using extra ribs but no stringers made more of a difference on the bottom and from certain angles things do look more lumpy than I'd like, but I'll probably be able to fix it up with some filler since this is just the first of two layers.
The plans call for the lower section of the bow to be carved out of balsa.
I decided to use 1/2" balsa sheet cut roughly to size and laminated on installation.
I also made a conscious decision to add these after the first layer of planking to allow me to cover them over with the second layer so that the whole hull looks planked.
It looks pretty awful to start with when roughly shaped, but planes and sands down quite easily to something that looks much better.
Compared to planking the hull it didn't take very long, so I also added some wood filler to smooth out the lower hull and bits of bow that were looking a bit rough.
A final bit of sanding and the first coat of sanding sealer is also now on.
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The plans call for the lower section of the bow to be carved out of balsa.
I decided to use 1/2" balsa sheet cut roughly to size and laminated on installation.
I also made a conscious decision to add these after the first layer of planking to allow me to cover them over with the second layer so that the whole hull looks planked.
It looks pretty awful to start with when roughly shaped, but planes and sands down quite easily to something that looks much better.
Compared to planking the hull it didn't take very long, so I also added some wood filler to smooth out the lower hull and bits of bow that were looking a bit rough.
A final bit of sanding and the first coat of sanding sealer is also now on.
I've been working steadily on the second layer of planking for a while, but since none of it made much of a visual difference I didn't post an update until it was finished.
Before starting the second layer I added a layer of 20gsm lining silk that I found on amazon and two more coats of sanding sealer. I decided on silk rather than tissue as I thought it would give me a stronger hull in the end.
The second layer of planking went on a lot faster than the first as I could clamp more planks in one go, and was much easier to bend and trim given the 0.5mm thickness.
The chine rubbing strip went on this morning with the help of some sniper tape I found in a drawer, which did a nice job of holding things in place while the glue set.
A load of sanding, and the first coat of sanding sealer is also done.
There are still some lumps and bumps as you can see from the photographs, but the hull looks straight and pretty symmetrical (the photo makes things look warped, but that's my photography skills).
Overall I'm pretty pleased with it for a first attempt at planking.
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I've been working steadily on the second layer of planking for a while, but since none of it made much of a visual difference I didn't post an update until it was finished.
Before starting the second layer I added a layer of 20gsm lining silk that I found on amazon and two more coats of sanding sealer. I decided on silk rather than tissue as I thought it would give me a stronger hull in the end.
The second layer of planking went on a lot faster than the first as I could clamp more planks in one go, and was much easier to bend and trim given the 0.5mm thickness.
The chine rubbing strip went on this morning with the help of some sniper tape I found in a drawer, which did a nice job of holding things in place while the glue set.
A load of sanding, and the first coat of sanding sealer is also done.
There are still some lumps and bumps as you can see from the photographs, but the hull looks straight and pretty symmetrical (the photo makes things look warped, but that's my photography skills).
Overall I'm pretty pleased with it for a first attempt at planking.
Painting the hull before fitting the running gear probably isn't the usual order, but I'm still researching brushless motors, propellers and all that side of things so I decided to just keep going. I'll have to fix up some of the hull paint once I add those things, but I think (hope) that it will work out ok.
I started off using crimson acrylic paint from Windsor and Newton because I had some. I found that it was slightly transparent, so switched to deep cadmium red instead, which worked much better. The upper hull was painted using mars black, also from Windsor and Newton.
Next up I used some 3mm water line vinyl tape (car trim) from Amazon.
The roundel and the number markings took some time. Initially I was looking for things that matched the plan, but noticed that the photos I have for 2757 have a later type roundel and numbering font.
I found a selection different sizes of the later type roundel without the yellow outline on the Castle Signs website.
I got the numbering from Vinyl Lettering Online, who supply custom lettering to your specific size, spacing and font on backing film - this makes it really easy to apply. I found that Open Sans Bold was a pretty good match for the numbering font shown in photos of 2757.
For the stern details I added a couple of 6mm eyelets as exhausts, then used 4mmx11mm staples and m1.2 washers to make the rungs of the ladder (all from Amazon). Gluing the staples and washers in place was really fiddly.
I made the ladder protectors from one of the 1.5mmx6mm mahogany strips that I got to do the deck planking.
Slightly late in the day I found a picture of the stern of 2757 on the RAF Museum website.
This showed that the number and position of the exhausts on the plan was wrong, but I decided to ignore that since they were already glued on.
It also showed details of vertical rollers on the towing hawse fairlead (if that's what it's called) in the hull, which I made up using some old sprue and plasticard that I had lying around. This detail isn't on the plan at all, or at least I can't see it.
I still have some portholes to add and the stern number (another detail shown in my late photo find and not on the plan), but the paint and markings have made a huge difference to how the hull looks.
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Painting the hull before fitting the running gear probably isn't the usual order, but I'm still researching brushless motors, propellers and all that side of things so I decided to just keep going. I'll have to fix up some of the hull paint once I add those things, but I think (hope) that it will work out ok.
I started off using crimson acrylic paint from Windsor and Newton because I had some. I found that it was slightly transparent, so switched to deep cadmium red instead, which worked much better. The upper hull was painted using mars black, also from Windsor and Newton.
Next up I used some 3mm water line vinyl tape (car trim) from Amazon.
The roundel and the number markings took some time. Initially I was looking for things that matched the plan, but noticed that the photos I have for 2757 have a later type roundel and numbering font.
I found a selection different sizes of the later type roundel without the yellow outline on the Castle Signs website.
I got the numbering from Vinyl Lettering Online, who supply custom lettering to your specific size, spacing and font on backing film - this makes it really easy to apply. I found that Open Sans Bold was a pretty good match for the numbering font shown in photos of 2757.
For the stern details I added a couple of 6mm eyelets as exhausts, then used 4mmx11mm staples and m1.2 washers to make the rungs of the ladder (all from Amazon). Gluing the staples and washers in place was really fiddly.
I made the ladder protectors from one of the 1.5mmx6mm mahogany strips that I got to do the deck planking.
Slightly late in the day I found a picture of the stern of 2757 on the RAF Museum website.
This showed that the number and position of the exhausts on the plan was wrong, but I decided to ignore that since they were already glued on.
It also showed details of vertical rollers on the towing hawse fairlead (if that's what it's called) in the hull, which I made up using some old sprue and plasticard that I had lying around. This detail isn't on the plan at all, or at least I can't see it.
I still have some portholes to add and the stern number (another detail shown in my late photo find and not on the plan), but the paint and markings have made a huge difference to how the hull looks.
Some small bits and bobs of progress this week.
I added stern numbers and porthole frames, then some gloss varnish over the entire hull.
Next, I completed the first bit of superstructure - the hatch cover between the main cabin and the raised engine room deckhead. The hatch will be removable on the model to maximise access to the hull space.
The hatch is made from 1.5mm ply with 1/8" x 1/16" edging and 1/2" square balsa underneath to keep the ply flat. The scuttle and inspection hatches are from Mac's mouldings.
I used Humbrol acrylic no 127 as the main grey colour with a Windsor & Newton burnt umber wash to pick out the details and add some dirt.
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I added stern numbers and porthole frames, then some gloss varnish over the entire hull.
Next, I completed the first bit of superstructure - the hatch cover between the main cabin and the raised engine room deckhead. The hatch will be removable on the model to maximise access to the hull space.
The hatch is made from 1.5mm ply with 1/8" x 1/16" edging and 1/2" square balsa underneath to keep the ply flat. The scuttle and inspection hatches are from Mac's mouldings.
I used Humbrol acrylic no 127 as the main grey colour with a Windsor & Newton burnt umber wash to pick out the details and add some dirt.
No actual progress on the boat itself this week, but I made a stand for the hull to enable me to take it off the build jig for the first time.
It turns out that Hobby Craft sell a plywood box which is just the right size to sit between bulkheads 2 and 4 on the plan. All I had to do was remove the lid and trace and cut out the bulkhead shapes from the ends of the box.
I used deep mahogany wood stain to make it look a bit nicer and some red self adhesive felt (also from Hobby Craft) to protect the hull from scratches.
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No actual progress on the boat itself this week, but I made a stand for the hull to enable me to take it off the build jig for the first time.
It turns out that Hobby Craft sell a plywood box which is just the right size to sit between bulkheads 2 and 4 on the plan. All I had to do was remove the lid and trace and cut out the bulkhead shapes from the ends of the box.
I used deep mahogany wood stain to make it look a bit nicer and some red self adhesive felt (also from Hobby Craft) to protect the hull from scratches.
I got a pair of 40mm x 26mm brass rudders from Cornwall Model Boats a couple of weeks ago, but after spending so long planking the hull I didn't want to rush into drilling holes in it.
The threaded tubes for the rudders were 8mm diameter, which was a bit close to the width of the hull bracing planks for my liking. To make sure I didn't destroy the planks when drilling I added some extra bracing along the sides, along with another plank to give enough depth for the threads to tighten.
I also added a couple of spring strut end joints connected by a length of M8 Rod mounted to the keel. The idea is that this will keep the rudders aligned and reduce the stress on the hull when they are pushed and pulled by the servo - probably total overkill, but I'm happy with it.
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I got a pair of 40mm x 26mm brass rudders from Cornwall Model Boats a couple of weeks ago, but after spending so long planking the hull I didn't want to rush into drilling holes in it.
The threaded tubes for the rudders were 8mm diameter, which was a bit close to the width of the hull bracing planks for my liking. To make sure I didn't destroy the planks when drilling I added some extra bracing along the sides, along with another plank to give enough depth for the threads to tighten.
I also added a couple of spring strut end joints connected by a length of M8 Rod mounted to the keel. The idea is that this will keep the rudders aligned and reduce the stress on the hull when they are pushed and pulled by the servo - probably total overkill, but I'm happy with it.
I've got a couple of ideas for how to set things up.
There's plenty room at the sides for the arms that came with the tillers, but not quite enough at the stern. I can trim them a bit if necessary, but I don't think they'll need a full 180 degrees of movement to provide decent steering so it might well be OK as is.
As for the servos, I've got a couple of ideas to try.
My initial plan is to use the arms aligned as they are in the picture and connect each outer tiller arm to the corresponding outer arm on a single servo sitting on the keel.
If that doesn't work, I'll try something that is probably more standard - using an 'L' shaped arm on one of the tillers, connecting the tiller arms aligned with the keel together and connecting the other leg of the 'L' arm to a single servo.
I made my servo horns for my RTTL from an old 3-pin plug and 2 strips of brass. Also, I use what is known as a closed circuit system for the push rods to the rudder servo whereas the 2 rudder horns are joined together.
One thing about diagonal planking - you do seem to be going on forevermore putting planks on - getting no where and all of a sudden it is done.
I myself have diagonally planked several hulls; even the one you are building the RTTL hull - and I tend to add stringers from bow to stern - maybe 2 on the side and 2 on the top - of each side of the hull. This serves 3 purposes; 1 it aides a bit more strength to the hull, 2 you can follow the true shape of the hull as in concave of the bottom and on the sides, 3 it gives you an extra place to clamp your planks to.
If you have a look at my photographs in my profile, you will see the RTTL model which I built there.
Are you making it twin prop? or, some of these vessels were triple props if you want a bit more excitement.
Good luck with the planking and the model. It is a lovely model to sail.
John
I did think of doing stringers instead of ribs, but in the end went with ribs.
That could be a mistake, but if so it won't be my first and hopefully it won't be terminal.