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[JerryTodd]

Took all three models to a Model Expo at the Chesapeake Bay Maritime Museum on the 18thPride actually free-sailed for the first time!

[JerryTodd]

  My friend Mark sailed his 46 inch schooner Cliodhna (Clee-na) for the first time in the pool at National Maritime Day (May 2022).

He controls the sails with a sort of clothes-line system driven by a winch.  A common system in RC sailing models, especially schooners, and what I originally intended to use in Pride.
The winch drives a closed loop and the sails' sheets are attached at points so the loop's travel pulls the sheets the requisite length for each sail.  Mark used one loop to control the over-lapping jibs, and the other loop controls all the rest of the sails (the ones with booms basically).
 Watching this work so well in the pool, especially with the over-lapping jib, I started rethinking Pride's set-up - again.
  
 I could finish this model if I could work out the controls, and what I was working on I don't think was going to work.  Sometimes the first idea winds up being the best idea, with some adjustment,
 First off; I already plan to remove the motor.  There's no way that that 1 inch prop is going to move all that sail in even against the slightest breeze.  The motor will go to the upgrade of my rope-walk.
 With the motor gone, the Rudder servo can be moved aft to where the motor was, closer to the rudder and the receiver, so I won't need an extension cable.
 Two winch servos with be re-mounted just forward of the rudder servo, and the other end of their loops with be at the forward end of the main hatch, just behind the foremast. This should get me enough length to control everything, even, I hope, the square tops'l.
 
 Another step towards getting this girl in the water is the arrival of 50 pounds of lead shot.  Now to gather the materials and courage to cast a lead bulb.
 

[JerryTodd]

Everything but the prop shaft's been pulled out, and some changes were made in the plan...
The rudder servo gets moved a little further aft so I can access the screw that hold the arm through the cabin hatch, and putting it in or out, if the need arises, will be easier.
The winches will be mounted opposing each other; one aft where the motor used to be accessible via the Engine Room hatch with it's loop running to the foremast.  The other winch just aft of the foremast, accessible via the main hatch with it's loop running around the aft winch.  The makes the system narrower and easier to deal with though the hatches.
I printed a test gun for Macedonian a little while back, and sat it on Pride, just to see.  It looks perfect, or darn close.
I thought I had a pair of winch servos around here somewhere, but I haven't turned them up yet.  I have to mount the rudder servo and work up fairleads for the steering lines.  Then make up servo trays for the winches that include a pair of sheaves for turning the opposing loop, which means 3D modeling and printing some sheaves for all that.  I also need to determine the size and shape of the lead bulb.

I'm starting to think Pride may actually sail this summer.

[JerryTodd]

I pulled out the prop shaft and cut back the stuffing box tube, plugging it with epoxy.
I fit two beams for where the rudder servo would be put, and assembled them into a frame that was epoxied in as a single piece.
Next come the turning blocks for the steering lines, and making mounts for the winches.

[PICKETBOAT]

Looks very good and you seem to have all the potential problems covered.


If the control loop for the rudder will be running though eye rings (and there is nothing wrong with this) I found with my models that using light weight fishing line worked better than cord. It creates less friction, its less visible (therefore smaller eye rings can be used) and does not wear and fray. Running the line through very small lengths of copper tube where it ends at the servo arm meant that when adjusted to length the copper tube could be crimped flat with pliers securing the nylon without having to tie knots in it.


I have assorted sailing models that have been working for years with this method and all have been maintenance free.


Keep up the good work

[JerryTodd]

(FYI: I can't get the attached images into the body of the post, and they don't open full-size when you click on them.  In Firefox, I right-click the image and "open in a new tab" to see them full size without leaving the post)Constellation's steering lines run through screw eyes and have given me no problems at all.  Pride, on the other hand, is a bit more complicated.  The lines run to the sides, turn to s-shaped tube fairleads that direct them 90° and up through the deck so they come out on either side of the lazarette hatch.  On deck they will run through functional blocks in the waterways.  I'll be using Dacron line I walked from 3 strands of sail-tread (I used off-the-shelf Nylon line in Constellation).   That bit of tubing at the lazarette is the big friction machine, so to reduce it as much as possible I'll be putting functional blocks in the hull where the line makes it's first turn from the arm to the lazarette.
When testing the braces on Constellation, I hadn't walked any of the aforementioned Dacron line I was going to use, and used some cotton cord I had on hand instead.  There's a few eyes under Constellation's deck to guide the braces from the winches to where they come through the deck.  There was so much friction the system wouldn't function, the winches wouldn't budge at all!  In a panic, I hurriedly walked out some 12 foot lengths of Dacron and rigged it up.  It ran flawlessly and has since.
Mean-while, back at the ranch...

I pulled out the old servo-tray that was on the trunk for the fin, and reseated the main-mast step.  Made a pair of trays for the winches from 3/16" luan plywood and painted them yellow, because I had a can of red and a can of yellow spray paint, and I can't paint everything red. 
The old motor bulkhead was extended up to carry the aft winch tray, the blocks I put in when the rudder servo was forward were repurposed to carry the forward winch.
I 3D printed four copies of a pulley wheel I found on Thingiverse and re-scaled to 1 inch (25mm) to be the idlers for the loops.  They're mounted on the little blocks you see on the trays with #8x1" wood screws with a brass washer under each.

I rigged up the loops for testing, but I need to sort out the radio gear I haven't touched in a while, and charge everything up.  I measured that I have roughly 20 inches (50+cm) of travel on the loop which is much better than I was getting the first try (see: http://todd.mainecav.org/model/pride/model09.html )

The picture looking down at the model shows what access will look like with the deck on and the hatches open.

[AndyBiggs]

This is looking very impressive
Also had a look through your website, very interesting


Thanks

[JerryTodd]

Thanks Andy.
I 3D modeled Pride's guns over the last few days while I was distracted by other projects like a foot-bridge from over a drainage ditch so the spectators at an upcoming American Civil War reenactment can get from the parking area to the event.
I started by modifying my 18 pounder 3D model, but the number of bands are different, in a different place, and I'd need to remove that Bomefield cascable ring and the ER cartouche on the barrel.  I opted to make a new barrel from scratch.  The carriage was easy enough to rework into the right size and shape as Pride's.
I set the guns at 45⌡ with the muzzle down so it would drain resin from the barrel as it printed.  I printed four guns at once, and each of the four was a single piece.  I modeled the vent, and the breaching rings to be loose, but the resin hardened at these spots so the vent is clogged and the rings won't move, other wise the printed were perfect.  I'll replace the rings with brass so I can pass the breaching line through it.

The 6 pounders done, I hunted down everything I had, and looked for more, on the swivels.  Examining pictures the 1 pounder swivels were simply scaled down versions of the 6 pounders; so I re-scaled my 3D model and added that odd stock and the yoke, and printed two of them.I found out recently a stock was replaced on one gun and a friend of mine has the old one.  I'm going to look it over in August and if it's different enough, remake the swivels with the new data.

[JerryTodd]

Been working on another boat, a friend just acquired a Mariner 32 which needs some work and a lot of cleaning.  Tomorrow (12th) we're towing her to a marina to be hauled.
I ran a test of Pride's controls, and decided I need a tensioning system with some give to it, so I'm thinking of mounting some blocks on springs on the fin trunk and route the loops as shown in the picture.  Looking at some other peoples set-ups, this looked like it ought to do what I need.

[JerryTodd]

Rather than spring the blocks to each other, I'll put them on separate springs and mount them on a post.  This seems a better idea than springing them together.
I printed two more of the pulleys I used for the idlers, and some slab sides to make proper blocks of them.  I also printed a barrel and a prop.
Pride had three barrels forward of the cabin trunk while I was aboard.  This model has wood bands and needs iron bands, and a few other details added particular to Pride's barrels.
Since I remove the motor, the prop is only for show.  I stuffed epoxy into the shaft tube, and screwed the prop into that so it will freely spin as the boat sails.

[JerryTodd]

In 1981, Pride had three water casks set in front of the cabin trunk, that's what I'm trying to model...
That barrel mentioned before was too big, and modeled with wood bands.  In the 3D editor I resized the model, subdued the bands, and covered them with "iron" bands; placed chocks so it would sit on it's side, and in the slicer software, put a drain-hole in it's underside.
They printed great, except that making them smaller made the end walls to thin and they didn't print.  I'm thinking of using them as napkin holders.
Trying to fix the 3D model was more effort than starting from scratch, so I did that.  I modeled it solid and hollowed it in the slicer, as well as adding a drain hole.  I finally got three usable barrels.

On the sail control loops, I installed a block of wood on the fin trunk with a screw eye to mount the tension blocks for the loops.  I got 1.5mm braided polyester line which runs through those little brass blocks just fine, so I didn't use the 3D printed ones from the last post.  The springs and brass blocks are visible in the hatch to the right of the mast.  The blue tape tabs on the loops mark the ends of travel of the loops.  The aft winch is perfect, but I have to program the transmitter for the forward winch to do it's full 3.5 revs.

[PICKETBOAT]

The barrels came out very well and will weigh nothing so thus reducing weight on deck. Not an issue so much with a larger model like this but it all adds up and spoils performance and handling on the water.


I cast some small resin barrels for use on my own models and experimented with paint techniques to achieve a reasonably good wood effect. I primed them, then painted them a flat medium brown (oil based paint). When dry this was over painted with brown ink which ran between the staves highlighting them. The ink could also be manipulated a bit as it dried to create a pretty good grain effect. A second diluted layer can be added when dry to create knots in timber or repairs (some staves can be slightly darker). A coat of matt varnish with a very small amount of flat white paint seals the surface and gives a somewhat bleached effect (salt water and sun shine). Paint the hoops charcoal or gun metal not jet black.


   

[JerryTodd]

The lower masts are made using the "bird's mouth" method and almost float out of your hand    they're very strong though, and almost don't need shrouds.

The guns will be the heaviest things on deck; the servos, the battery, and of course the fin with it's lead bulb are all below the waterline.

The real boat was a wet sailor, with her deck barely 3 feet above the waterline.  I'm considering my hatch sealing options since all but the cabin trunk will be flush-deck hatches.  I'm probably gonna put in an automatic pump to keep her bilges clear, as water weight could be a problem.
Putting her deck together is a puzzle.  I need to at least paint the underside of the sub-deck.  The inside of the hull is fully coated in resin.  The bare wood beams are all painted with automotive antifreeze (glycol) which permeates the wood and crystalized, displacing water and keeping it from soaking in without shrinkage.  Pure glycol is used to conserve wood from shipwrecks.  You have to be careful with it, it can get through your skin and crystalize in your brain which will make figuring out these model boat problems even more difficult.  The other issue is some sub-deck needs to be permanently attached where the through-deck fairleads are, and I always get nervous permanently putting down a deck, worried that I'll lose access to something I forgot.  This sub-deck's been chopped almost to bits so I can fasten down the parts with through-decks with out loosing access.

Once the whole sub-deck and the hatches are in place, the seams puttied and sealed, it'll get a layer of light cloth and resin.  Then I'll glue down the 1mm thick bass strips that'll be the finished deck.  These will be stained, dipped in glycol and glued down, then coated with polyurethane for floors.

[JerryTodd]

Still working out where control lines will go through the deck, and putting blocking among the deck beams to hold the tubing.
When the heat gets to be too much, I retreat inside and work on 3D models.
One such item is Pride's Roll Bar.  I guess there was some concern over the weight of the mains'l and it's spars when lowered and hanging in it's lifts, pulling at the head of that highly raked mast; or maybe it slopped about too much when lowered and the boat under power, probably both?  At any rate, sometime late in 1977 she got a steel tube frame work to act as a boom crutch mounted on her taffrail, which because of it's appearance and construction, was always referred to as the "Roll Bar."The little collage picture shows a couple of views of the real one, snips from my plan of the boat showing it, and a rendering of the 3D model I built.  I printed one just to check I had the fit right, but it's basically getting tossed and replaced with a more detailed set.  I've added more detailed to the 3D model, such as turksheads.  If it turns out these resin ones aren't up to the job, ie, I break them too often, I'll make a set from brass rod.

The bitts at the base of the main mast sport a windlass used to cinch up the main stays, hauls the fores'l sheets, and a few other things.  I made a set of winch drums for my friend's schooner model a few posts back, but they were a different style, so using photos, I eyeballed a 3D model of Pride's drums with the handles attached, and printed them.

[ScottW]

Quite the engineering going on here. That 3D printing has added so much to model making. I've seen various people on hobby forums create everything from 1/144 scale airplane pilots to 1:20 scale 1800s Nevada silver mine buildings for their garden railway trains, & all kinds of functional mechanical parts for operating models.

[JerryTodd]

I just used it to print a gizmo to repair the IR light mount for the head-tracking device I use in gaming (light gray thing, center-right in pic).  Broke and repaired all in the same day - 3D printing is great! 

[JerryTodd]

I threw the model into the tub and loaded her up with weight down to a centimeter of her waterline.  Deducting the weight of her battery, my brute-force calculations say she needs 11kg (25pds) of weight in the bulb on her fin.
I don't have the tools to melt and cast lead, or want to get them for a one-off job, so I was leaning toward either epoxy casting the lead in a mold, or a container.  I put 40ish pounds of lead shot into a PVC pipe for Constellation which was safe, clean, cheap, and didn't require any tools I didn't already have.  As noted, one tool I do have is a 3D printer, and here it comes to the rescue again...
I made a ball in my Anim8or 3D software, to be the inside surface of my bulb.  Stretching and squeezing it turned it into an ellipsoid.  Now, how do you calculate the volume of an ellipsoid?  You go to a handy-dandy Ellipsoid Calculator and play with the numbers until you get the volume you want.  Once I had the dimensions to get 60.62 cubic inches of volume, which times .41 (the weight of a cubic inch of lead), gives me 24.9 pounds.
With the inside dimensions settled, I made a copy of the inner surface to make an outer surface, covered the gaps between them making the bulb's walls about 4mm thick.  I then added some structure to seat the fin inside and divided the model into quarters so it would fit in the printer, where it'll take 6 hours to print the half of it that'll fit.
When it's printed, I'll bond the quarters to each to left and right halves; each of which I'll fill with lead shot; pour in epoxy to solidify it, then bond the two halves onto the fin.  I'll drill a hole through the bulb and the fin for a pin to make sure I don't unexpectedly drop a depth-charge.  I'll give the outside a coat of epoxy to toughen it, and it'll all get painted moss green to match the model's bottom.

[JimG]

You don't need any casting equipment to make a lead bulb, just laminate it from lead sheet like a bread and butter hull. Look for lead roof flashing  to get suitable sheet, this can be epoxied together before shaping. Lead can be shaped with a plane, I think kerosine is recommended as a lubricant while doing this. Many years ago I made a bulb for a Marblehead yacht and the final shaping was done with a razor plane.
Jim

[JerryTodd]

Lead sheathing is hard to come by here anymore.  Besides, I already have 70 pounds of 7.5 shot, and a gallon of epoxy.
Not to mention I'm half way through printing my dodo egg

[JerryTodd]

All four quarters printed, and a pair of each bonded to make two halves, it's time to load 'em up with lead.

[nemesis]

I hope, when all is cut and dried that you do not find it too heavy and you have to remove some lead. nemesis

[JerryTodd]

I doubt "too much" will be an issue, I left some leeway to put weight in the hull to trim her about 1/2" below the waterline at the bow, and 1/4" at the stern, since sailing will tend to push her head down.
I sifted the dirt out of my "reclaimed" lead shot and filled the two bulb halves, but it was too cold to pour epoxy.  It was supposed to be in the low 60's (f) today, but the resin was too thick to pour into the mixing cup, so I brought it into the house to warm up for another try.
After a day inside, the resin seemed more amenable to pouring, so out in the shop while is was still 60°f (11°c?) out there, and attempt the pour.I mixed a full yogurt cup's full and poured it into each half.  I was left with about 1/3 of the cup, so that I poured into the bilge and propped the model up so it would fill in the deadwood area.

[JerryTodd]

I've gotten a few question on how the bulb will be attached to the fin.  There's a hole in the fin near it's bottom, and I've drilled matching holes in each half of the bulb, not all the way through.  A metal pin will be trapped in these holes when the bulb is epoxied together, so epoxy and this pin will keep the bulb on the fin.
Pride had four boats when I was on her: a lapstrake pulling boat that sat on top of the stern davits the whole time;  A double-ended boat that was half whaler and half life-boat and referred to as the "Bequia boat;" and two inflatables, one new gray one, and one scruffy old orange one.
I sort-of 3D modeled the orange one and printed it.  It's a very simple model of an inflatable, but I think it gets the point across.  I am looking forward to getting asked why my War of 1812 Baltimore Clipper has an inflatable boat on it.

[JerryTodd]

Finally the temperatures and my time have coincided enough that I may finally get closer to getting this ostrich egg finished.
 
 It seems the plastic egg deformed a little from the weight, so the two halves don't lay flat to each other. If I do this again, and for you folks thinking of using this method, I will put ribs inside the bulb to stiffen it, and fashion some sort of cradle to sit it on that supports it so the bulb doesn't try to flatten out as the lead and epoxy set-up.
 
 There were also dry pockets in the bulb that resin hadn't gotten to and I could hear the shot rattling around inside.  If there's a next time, I'll place shot and pour resin in layers to ensure the resin gets everywhere it needs to be. What sounded like the biggest of these pockets was behind the flange? I had modeled in for the plate to slide into. I opened the holes here to pour more resin in and hopefully fill this void.
 
 I re-drilled the holes for the pin that will keep the bulb from sliding off the plate, and cut about a 3 inch length of 3/16" brass rod for the pin.
 I mixed very fine sawdust from my band-saw with the epoxy to make a paste of it, buttered both sides of the bulb, placed the pin, and plate, and put the other half on.
 
 I used a sliver of wood as a wedge to hold the seam on top, where the plate enters, as close as I could, making something of a gap at the bottom. The epoxy butter filled this in fairly well, but the seam's open almost all the way around, which I'll fill with more epoxy butter.
 
 The bulb also needs some clean-up from epoxy runs and cardboard that stuck to it; and I intend to wrap it in glass cloth as that'll be stronger than the resin alone if the boat should hit a rock or something.