“EeZeBilt 50+” Sea Princess build

[Bob Abell 2Participant @bobabell2]

Hello Diedie

I like your hull shape with it's strakes

The gray covering looks interesting, will you tell me about this "Spray Putty" please

Bob

[Diede van AbsParticipant @diedevanabs87670]

The spray putty is a Motip rattle can, it is essentially a filler but I suspect a bit thicker as Motip also carries a Filler (colored green-ish) but I feel the Spray Putty fills the holes and dents a bit better. It is acrylic based, which is not a problem for me as I will spray paint the boat with Revell Aqua paints. If you use enamels it might be a different story, though – so then first try it out.

[Mark Jarvis 2Participant @markjarvis2]

HI Bob

The paint you are asking about is widely available, Halfords, Ebay etc. Basically it is thick paint used to build up damaged areas, or cover scratches and dings.

PM me for more details

Mark

[Dodgy Geezer 1Participant @dodgygeezer1]

Posted by Diede van Abs on 22/09/2014 08:35:58:

Of course, Amy Jane. There is a nice brushless outrunner in my stock, for this boat. I think power will be the least of my challenges ;-

If it is anything like the prototype (and I guess it must be..?) then it will be incredibly light. I'm not sure how it will behave on a windy day with a bit of power – I thought mine might blow over…

[Diede van AbsParticipant @diedevanabs87670]

Hi DG,

You are right, it is quite light – in spite of me having used 3mm ply for the keel and superstructure sides, as you recommended on your site. The basic hull as it is now, weighs in at a mere 590 gram – excluding main- and aft roofs, but including all the masking tape and newspaper wrappings for painting.

Assuming that the weight will be doubled by the gear and detailing, then still it is a boat of only 1,2kgs which is pretty neat for a boat of this length, I think.

You never posted a picture of your completed prototype on your site, I am quite curious what your end result looks like and how it goes?

[BalsadustParticipant @balsadust]

I have started the Sea Princess at 1.5 times the original plan size! Any idea's on a suitable motor and prop to suit. This is my first model boat build for 55 years and keeping everything crossed, it floats ! Regards

[Diede van AbsParticipant @diedevanabs87670]

Wow, that must be quite a model you are making! Close to 1m I reckon?!? I thought the original size Sea Princess was a decent size already – although, admittedly, compared to Bob A.'s VGC it is just a gnat in the waves…

I don't have a decent advise for a motor and prop size, although I would definately go the brushless outrunner route with a nice and beefy outrunner. But here goes my "not based on anything but gut feel" advise:

Unless someone else comes up with a better advise (and I am sure they will) I'd aim for the 12.000-14.000rpm (unloaded) ballpark and, say, a 45-50mm prop with a good, speed-inclined pitch… say, in the 1.3-1.4 region. Sea Princess is definately a performer type of craft and should not be under-powered, is my humble opinion.

An outrunner matching the prop could be a 36xx (36mm dia) motor, the kV value depending on the batteries you intend to use. Your boat is big enough to not care about a bit overkill on the power-side, so pick one that has plenty oompf. Say, something around 500-700W. With a bit of luck you can then run it without active cooling…

Please, DO post a work log of your build!!! I'd love to see a big Princess coming together!

[BalsadustParticipant @balsadust]

Thank you for the prompt reply and send the first photo of Sea Princess. The motor I intend to install, based on your suggestion, is a Turnigy Aerodrive SK3 3548 – 840 kg with 4000 3s Lipo's. ( leftovers from my grandsons model aircraft days ) These seem close to your advice. Now prop shaft dia?

Please feel free to comment – the last motor I installed in a boat was a " Mighty Midget " powered by 4.5 v battery

[Diede van AbsParticipant @diedevanabs87670]

Your photo doesn't seem to work, alas…

I cannot advise you on a decent prop shaft, as I simply do not have experience with such lengths shafts.

For my Sea Princess I used a simple Robbe or Graupner item (not sure any more which…) but I am not sure if they even have long enough shafts, and if these shafts are capable of these speeds at these lengths (risk of whipping in the tube).

[BalsadustParticipant @balsadust]

[Dodgy Geezer 1Participant @dodgygeezer1]

@Balsadust

….I have started the Sea Princess at 1.5 times the original plan size!…

Hmm… and I thought that 2ft was getting to be the biggest size that was sensible for this kind of structure…

I presume that you are doing this as an A4->A3 enlargement? In which case the boat will be a little over 32"..

The first point to make is that, although these are intended to be simple 'starter' kits, modifying and expanding them probably needs a modeller with some experience. In particular, there are likely to be unsupported balsa runs which are just too long, and which need extra reinforcement.

Material thicknesses may need to change, too. 1/16" sheet is pretty thin, and 1/8" balsa can get floppy in big bits. You may want to go up to 3/16" in some places. The keel, in particular, will benefit from being ply, as would the superstructure sides. Certainly balsa should be hard…

I think a standard 4mm shaft should be fine. 4mm steel is pretty strong and rigid, and there is a good cheap choice of 4mm props. I don't know how fast you are thinking of running it, but remember that the construction is light, you will probably want to beef up the motor mount and battery supports, and if you hit anything at speed this construction will behave like a full size, not a model. In other words, where a fibreglass boat would bounce off the side, light balsa construction will simply cave in! It seems to me that an SK3 3548 might be a bit on the powerful side – these things can be very light and you want it to stay on the water!

Here is a link to a similar sized 'eezebilt' – a 34" Triton. (We would love to have photos of your 'magnum opus' when complete!) Note the extra bulkheads used to support the 16" skin. Remember that the skin may look flat when being built, but after a season or so of use you may start to see ripples down the side if the support is poor…

 

Edited By Dodgy Geezer on 24/03/2015 00:46:05

Edited By Dodgy Geezer on 24/03/2015 01:20:24

[BalsadustParticipant @balsadust]

Thank you for your comments all are duly noted And a 4mm prop shaft will be fitted. I had thought about beefing it up and will attempt to post photos prior to sheeting the hull complete with the strengthening mods for your comments. I have attempted to post photos with no success and I don't know what I am doing wrong. I use this iPad for the camera copy it from the photo gallery onto these messages and it appears, when I return to this web site the text has been transmitted with no photo attached Any ideas ?

I never ever gave hitting something on the water a second thought, is it possible and practical to put a glass skin over the completed hull to overcome this potential hazard Thanks for the advice. Regards

[Colin BishopModerator @colinbishop34627]

Re posting photos, check out the FAQ section on the right hand side of the page. To display photos you need to create an album first or link to an external photo hosting site. Large photo files as taken directly from a camera can result in a timeout when uploading.

Colin

[Dodgy Geezer 1Participant @dodgygeezer1]

My experience is that you need to copy photos to the gallery first, then write your piece and select 'input from gallery' when putting in pictures. I always make mine into 640×480 thumbnails.

I never ever gave hitting something on the water a second thought, is it possible and practical to put a glass skin over the completed hull to overcome this potential hazard…

Quite possible and practical – just not cheap, and the whole point of the 'eezebilt' range was to produce cheap, simple small models for beginners. I had hoped that experienced modellers would cut out the shapes, provide them to their grandchildren with a tube of glue, and introduce another entrant to the hobby. What seems to be happening is that older modellers are reliving their childhood, and newer ones are saying – "Nice boat – shame it isn't bigger.."! The boats are made of balsa because that's easier for children to cut, glue and pin than ply, which would be the obvious other choice.

Mind you, skinning in 1/16" ply would sort the problem equally well…

 

EeZeBilts are actually built, using their egg-box construction, with similar internal divisions to battleships. Ripping the floor out will not sink one, because there's a sub-deck just above the keel. There will always be a watertight bulkhead an inch behind the bow. Depending on the design, there could be several keel-to-deck other transverse bulkheads. But something big in thin balsa will always be delicate compared to carbon fibre…

 

 

 

 

 

 

 

 

 

Edited By Dodgy Geezer on 24/03/2015 20:14:20

Edited By Dodgy Geezer on 24/03/2015 20:15:30

Edited By Dodgy Geezer on 24/03/2015 20:15:51

[Diede van AbsParticipant @diedevanabs87670]

I actually treated my Sea Princess with tissue and epoxy, which – after some layers and a decent curing time – produced a very strong hull. I would not recommend tissue though, I did not like how it followed the hull shapes (or rather: did not follow). Use glass weave instead.

For my scaled-up Beaver I also scaled up the thicknesses of the balsa – for the frames more than for the skins. I ended up using 2 or 2,5mm skins and 6mm for the framework, which produced a decent stiff hull.

Glass fiber and epoxy or polyester is not that expensive – you should be all OK with some 30-ish quid for cloth and resin. Add some cheap throw-away brushes and equally cheap gloves, borrow the letter weighing scale (1-gram accurate) from your wife and you should be set. Oh, and of course an empty cardboard or plastic container to mix it all in – I use an empty box where they sell Bami in.

I think you should leave the thoughts of really REALLY cheap for these boats, they are very decent performers and even when using commercial prop shafts, brushless motors and resin reinforcements they are still pretty competitive priced. My smaller EeZeBilts did not exceed 30 euros a piece, the bigger ones will not go over 100 euro, even with the brushless gear, all the fittings, details and decals added. I did not exactly cut corners, budgetwise… so bottom line of this story: GO for the glass fiber and epoxy!

If you indeed reinforce the hull with epoxy and glass, there are three things that you need to consider:

-Treat both inside and outside with thinned epoxy (you can thin it with rubbing alcohol) so it impregnates the balsa and seals it

-Use a glass weave we here in Holland call "keperweefsel" which is woven in a specific way making it more plyable so it folds better over the compound curves. Not sure how it is called in English, but I am sure there are some specialist companies out there that can advise you on it. Furthermore, consider the number of layers you want to add, and use a very light weave (the lightest I can get here is 30gr/m2) as top layer. This saves you a ton and then some on sanding & filling afterwards. Apply at least one additional layer of resin without glass before even thinking about sanding and filling.

-Also, don't wait too long sanding epoxy; it takes a while to cure but you should be able to sand it some 18-24 hours after applying. Waiting longer will result in more elbow-grease while sanding.

 

@ Dodgy Geezer; the problem with the original-sized EeZeBilts is that they are only JUST suitable for RC and only fit for running them on small ponds with almost no ripple. Scaling them up a bit produces very nicely sized hulls that are both compact enough to take with you on a bike and still have enough room for RC equipment plus extras – AND they handle waves better. Sea Princess does not need any scaling though, as far as I am concerned, she is big enough already as-is and I am sure she can cope with a wave or two without too much ingress…

Edited By Diede van Abs on 24/03/2015 21:16:51

[Dodgy Geezer 1Participant @dodgygeezer1]

You CAN R/C the original small EeZeBilts, but it is an expert job given the amount of space you have to play with. But an EeZeBilt SHOULD be small – for most of its life it will sit proudly on a childs shelf in their bedroom as a display item, and mothers won't put up with something bigger than 18"!

An EeZeBilt also should be cheap, and the basic costs are – even if two cans of spray paint and a half-litre of sanding sealer alone is 15GBP… and motors cost a lot…

I cheat a bit by buying cheapish brass tube in bulk, then making up my own propshafts and connectors on a lathe. But I expect to make most of the boat fittings out of copper wire and tin cut from food cans, both of which can be found in a skip. For example, here are a few shots of the prototype PT-boat (still needs detail painting), which probably counts as big at 20". Running from back to front:

• The smoke generator is balsa turned in a drill with a nut attached.
• The cleats are tinplate soldered to a bit of copper wire
• The twin oerlikon is brass sheet (could have been tin!) with some brass tubes and copper wire on a biro tube
• The torpedoes are turned balsa with brass sheet (could have been tin), held in styrene sheet mounts (the base of an old toy).
• The ventilators are bought – from my bits box…
• The machine guns are brass tube and a bit of brass square section (ok – I needed to buy that…)
• The figure is a 1:48 bought one…but the ship's wheel is soldered copper wire
• The life-raft is silicone tube with copper wire inside
• The 37mm is a bit more of the square section, with some brass tube. The flat magazine sides are beaten copper wire, and the mount is a felt-tip top.
• OK, the numbers are vinyl. But I did use stencils on my Fire Tender… and there's some piano wire in there as well.

Approximate costs in GBP

• wood – 6
• glue – 2
• fittings – 8 (brass cost – lots left!)
• Motor and ESC – 12
• Shaft, prop and connector – 4
• Paint – 12

 

 

 

Edited By Dodgy Geezer on 24/03/2015 23:38:14

Edited By Dodgy Geezer on 24/03/2015 23:45:53

Edited By Dodgy Geezer on 24/03/2015 23:46:21

[BalsadustParticipant @balsadust]

Thanks for the comments and you are correct I posted the photo and then added the script and it looks to have worked !

[Diede van AbsParticipant @diedevanabs87670]

Hi DG,

You are absolutely right in making fittings yourself – I tend to do that too. But please realize that nowadays, most kids won't build an EeZeBilt to sit proud on a shelf. They build it to float it. RC and all. Add to that the increased wealth and fathers with less time to help making up propshafts and all, and you end up with a scaled-up EeZeBilt with commercial rudder and propshaft.

As for the costs of my EeZeBilts: The bulk of the cost for me is the brushless motors and ESC, even when getting them from China it's still the biggest money-drain. I think the combination costs me around 30 quid per boat, give or take.

I just think it is a bloody shame to cut corners on these models, just because 50 years ago we weren't able to utilize these techniques. I think EeZeBilts are great models and a credit to their designer(s) that they are so easily built and adapted for modern techniques while still maintaining a very attractive and "different from others" look. I mean, come on… A completely built EeZeBilt, including resin, glass, a ton of fittings and quality RC equipment is still a LOT cheaper than even the cheapest basic kit (excluding fittings, paint and RC) out there nowadays…

Oh well, so much for my rant on this topic. I think we need to agree to disagree on this…

[Dodgy Geezer 1Participant @dodgygeezer1]

I think we need to agree to disagree on this…

I'm not sure we are disagreeing – I also think that these boats are for sailing, and I am very happy that expert modellers such as yourself find them worth making. There are few boat ranges that lend themselves to modification so easily – your 'double depth' Otter is a classic example. The web site has examples of all kinds, including EeZebilts made in card and Depron. There are even solid models…

**LINK**

They can be made to exhibition standard or slapped together without much care and still perform (I shall forbear from providing illustrations from the net!). I'm not so unhappy about 'cutting corners' – I remember my own feeble attempts at starting to build model boats 50 years ago before I understood anything about painting (I haven't improved much over the years), and note that the key point about your first model boat is that YOU have made it – well or badly, it's still YOUR BOAT sailing across the lake… That said, I stand in awe at some of the superb results that you and others have achieved, and have no difficulty with the use of modern materials and techniques to achieve them. I'd just like to ensure that a decent model can be made at a low cost, suitable for entry-level persons.

The bulk of the cost for me is the brushless motors and ESC, even when getting them from China it's still the biggest money-drain. I think the combination costs me around 30 quid per boat, give or take.

Hmm… motors depend on boat size, of course. For small boats I suggest a small brushed motor and esc on the web site. These are currently advertised at

• Motor 50p (Euro 0.68 )
• Esc – 1.30 GBP (Euro 1.76)

**LINK**

**LINK**

 

For the larger faster Eezebilts, a small brushless and a 40mm prop seem to work fine. I find the EMAX CF2822 is easy to buy at around GBP12-13 INCLUDING an ESC – here is a UK EBay page of them:

 

**LINK**

 

The Sea Princess may need something a bit bigger, but I would not be surprised to find this motor getting it up on the plane with 10-12v. I run at 7.2v myself….

[Diede van AbsParticipant @diedevanabs87670]

Hi DG,

Thanks for calling me "expert modeler", I think that is a bit too much honor for me as I am just starting (only building for 4 years or so now).

I believe (not sure of the exact numbers right now, as it all is in storage now due to a house rebuild project) the motor I have chosen for Sea Princess is calculated based on 2S LiPo or 7.4V, voltage not being a key factor in having a planing boat. A higher kV motor on lower voltage can send a boat soaring across the lake equally well, at the expense of more amps being drawn. I do know though, that the motor I chose is "a tad bit" overkill – it helps keeping the motor cool without water cooling. That might have added to the expense – and the shipping, of course.

For the Beaver I got myself a 890kV outrunner, lovely motor and when run at 7,4V it should produce more than enough oompf to tow or push something around with ease.

Here in NL an ESC of €2,- or less is "a happy dream" – not going to happen, unless you cannibalize a servo and use that as speed controller and ESC. The first decent-performing, micro ESC here is about 20,-.

That solid-hull Terrier is a good looking model!

Balsadust, can you please try again to post pictures of your SeaPrincess++? I still would like to see them…

[Dodgy Geezer 1Participant @dodgygeezer1]

Thanks for calling me "expert modeler", I think that is a bit too much honor for me as I am just starting (only building for 4 years or so now).

Ah, but you are obviously born with it…

 

Here in NL an ESC of €2,- or less is "a happy dream"…

Odd. What happens when you click on that link? I see that it's out of stock at the moment, but here's a similar one from the Hobbyking European warehouse at around Euro 4.86:

**LINK**

..which isn't too bad. I suppose brushed ESCs will slowly become redundant, so get them while you can! I bought a dozen of the GBP 1.30 ones a few years ago…

I do know though, that the motor I chose is "a tad bit" overkill – it helps keeping the motor cool without water cooling.

Here is the motor bay for a PT-Boat – this one is a Tower 2410-12T, which is fairly similar to the EMAX CF2822. They are both around 30mm diameter and 30mm front to back. I have been running this one in the domestic test tank (bath) off a 7.2 hi-output pack with a 32mm prop (cut down 40mm), and it didn't even get warm to the touch, while pushing out enough thrust to skip over the surface like a hydroplane…

Edited By Dodgy Geezer on 25/03/2015 16:04:29

Edited By Dodgy Geezer on 25/03/2015 16:06:13

[Diede van AbsParticipant @diedevanabs87670]

Ah – I clicked the links and that explains a lot.

The ESC's you refer to do not have reverse and are meant primarily for planes and speed boats. I somehow like to have a reverse option on my models, especially the tugs but also on other models (my two speed boats and TAMAR excluded). Reverse seems to make ESC prices go sky high… I did however find some 10A chinese micro ESC's that do reverse without brake (BRAKE is a big NO-NO in boats, is my experience) for about €10 each… when ordered per four or so to save shipping. They are damn hard to find though, most have that stupid BRAKE function and are aimed towards cars.

I really like the characteristics of outrunners, them being extremely powerful and with tons of torque to swing a big prop no problem. I believe you when you say that this little bell-type motor will send the PT boat skipping like mad when at full thrust! A properly chosen outrunner and ESC is a bliss for us boaters.

Again though, me being an expert builder: I certainly know my thing, but I build my models to a standard that is pleasing to the eye, but it's certainly nowhere NEAR expert-class quality. Thanks for the compliment, though.

[Dodgy Geezer 1Participant @dodgygeezer1]

The ESC's you refer to do not have reverse ….. I did however find some 10A chinese micro ESC's that do reverse without brake…0

Yes – I mention this on the web site. You are correct that tugs especially need a reverse, and I had wondered about doing this cheaply by including a mechanical servo cross-over switch between the motor cables – with some kind of interlock device to prevent reverse engagement at full speed…. but there do seem to be a few around now. Here's one at 8 Euros, delivery included:

**LINK**

You will see a small flywheel on the motor above – I find that this helps a reliable slow speed quite a lot, which can be a problem with small brushless motors.

Actually, the big cost for me is batteries. I like to have a set for each boat – and the brushless motors prefer expensive high-drain types. The PT-Boat above has a 7.2v saddle pack which cost the best part of £20 – I should really build my own…

[Diede van AbsParticipant @diedevanabs87670]

Hi DG,

That ESC you are linking to is very similar, if not the same, as what I had here (after one or two attempts that got me ended up with ESC's WITH brake…). For their money, and for small brushed motors, they are pretty nice.

I actually don't have much issues with outrunners at low speeds, although I did have a big mis-buy one time when I bought myself two outrunners that looked great on paper – only to find out they were heli-motors with strong magnets and only a few, thick-wire wound, coils (poles). They only jumped into action at about half throttle or so… I am checking as good as I can how many coils can be counted on the photos advertized, as this number is rarely mentioned in the descriptions. The more coils the better, I now use the gold-colored series from Hobbyking and they tend to be pretty nice at low and high revs alike.

Batteries can be pretty expensive as well indeed, so I try to stick to a couple of standard-size packs for the bigger boats and use them for multiple different models. The smaller boats often get their own batteries, as weight is much more of an issue with them. I completely switched to LiPo batteries by the way, much more power for the money and the weight.

Man, I should totally start building again, mind you… but I still need to move all the stuff out of the garage first back into my room and the attic….

On a totally unrelated note, this might interest you: building a 3D printer mainly from recycled CDRom players and floppy disks. I am very much tempted to build me one.

[Dodgy Geezer 1Participant @dodgygeezer1]

I stayed away from LiPos – they seem to need a fair bit of organisation! You can't just leave them at the bottom of a building box for 6 months, then give them a quick charge, take them off to the pond and expect to run them 'til they're flat …! Though if I want to R/C a standard sized CURLEW, the low weight would come in handy.

Your CD printer was indeed interesting – how did you know that I'd been looking at numerically-controlled routers? I would love to be able to draw a boat, then slap some balsa on a cutter and assemble the result. That would be one way to cut down on my drawing errors!

To do that you need a cutter capable of cutting very soft wood, with a bed of around 36"x4" – the standard balsa size. I had never thought of using floppy drive motors, but they would probably be strong enough…?

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