new build

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Hi everyone

Well it's been a bit of a tumultuous year, but I'm back on deck and ready to start my new build.

Whilst flicking through my design file a while back, I came across this.

Just a rough sketch of an idea I had at the time. When my father died some years back, I ended up with his Homelite outboard motor. This is an American built 4 stroke, of about 50hp, dating from the '60s. It was a good motor, even though 30 odd years old. I dreamed up this boat, 30' long by 6' beam. The idea was to have a boat that I could take a bunch of my friends out on for the day at a economical 7 or so knots, but would still get up on the plane at 15 or so when not full of people. This was intended to be achieved the odd stern shape in the plan view. The logic was to give plenty of bottom area aft for planning when light but to have a narrow transom to reduce drag when heavily loaded. It was a pipe dream, and never got built. I see no reason why I shouldn't build a rather large scale model of it though….

Aj

[Amy jane SeptemberParticipant @amyjaneseptember49770]

[Kimosubby ShipyardsParticipant @kimosubbyshipyards]

Hello Amy,

looks good to me, and hard chine is is a favourite hull method for me too. I've build yachts with hard chine, and used the 'mirror dinghy' method of holding together whilst the glue took – wire through two holes and twisted up tight everywhere a fixing was required. Once set, cut the wire and pull out, ten fill holes with bamboo dowels.

I must look up the outboard make, most outboards from that era were two strokes.

I'll keep my eye on progress, have fun, Kim

[IAN_IParticipant @ian_i]

Hi AJ…

Looks interesting, good luck with the build.

Is this the winter project?

Ian

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Hi there Ian and Kim.

Thanks for the comments. Yes, a winter project,and hopefully a fairly quick build.

Kim. I feel that the hard chine shape offers a lot on this sort of boat, and the build will be very much as you describe. Preshaped ply sides wrapped around ply frames with no building jig.

The Homelite ( also came out as a Bearcat) outboard was a innovative thing for it's day. If I remember correctly it was a 4 cylinder cast iron block! Rather heavy, but quite reliable. We had it on a 20' cabin cruiser, which gave us about 18 knots flat out.

Aj

[Andy CParticipant @andyc56856]

Hi Amy J.

Nice to see you back, all is well, I hope? Good looking new project you have there. Nice lines. Will watch with great interest.

Andy

[ashley needhamParticipant @ashleyneedham69188]

AmyJ. What are you proposing to use as an outboard for this interesting project?

Design file….cor…I just have a list !

This will also need an action man (or something) to crew it. Difinately. How big/what scale are you thinking?

Ashley

[BanjomanParticipant @banjoman]

Hello Amy jane!

This looks like an exiting project, and I look forward with great interest to following its development!

/Mattias

[Ralph PinchParticipant @ralphpinch41762]

Hi,

have to admit that I had to google what hard chine building method was, I've got a lot to learn.

The design looks great.

I look forward to following the build.

P.S. What size will it be?

Ralph.

[Kimosubby ShipyardsParticipant @kimosubbyshipyards]

I looked up the boat engine, interesting history and certainly well ahead of its time being a 4 stroke outboard. Also interesting to note that it was a small car engine 'turned on its side'. Must have been quite a small car, our Peel cars are single seaters but ran on a 2 stroke engine.. We must have had dirtier fuel this side of the big pond so used oil in the mix. I remember my first outboard, a 1.5Hp Seagull, which actually ran on anything, but the tank filler cap was stamped 10:1 oil mixture, almost paraffin, these days it;s more like 100:1 or higher.

Winter has already started for us North of the Watford Gap, barely had temperatures over 16 this summer and it's been wet and windy too.

Enjoy the build Amy J, I expect to see some unusual and unexpected work from you as always. Hand built model outboard to start I should think.

Aye, Kim

[Amy jane SeptemberParticipant @amyjaneseptember49770]

HI all

Bearcat

Hopefully this will work.

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Thanks so much for the interest, I shall endeavour to answer some questions.

Hi Andy, thanks for looking in. Things are ticking along now thanks

Ashley, well, as for an outboard, I think I shall use an outboard!

Hi Mattias, I'm afraid this will be a simple build, compared to your fine work. Glad to have you along!

Hi Ralph. Hard chine boat design is a fascinating topic in it's self, even the various names they were called is intriguing. V bottoms, file bottoms and corner boats among others.

Kim. Sounds like a nasty summer for you lot up there! 16 degrees is an average winters day here, though we do get a handful of sub zero nights. Lots of wind and rain too though. Those peel cars are hard case! I'd love to have one, though I'd want to take the little 2 stroke out and put in a small Tucumesh side valve! As for a home made outboard, I have made 6 over the years! the smallest is made from a weed eater, with the shaft cut off and an old angle grinder gear box bolted on. Made it a good many years ago, and it is still in regular use. Pushes my 14' skiff along just grand! A couple are lawn mower engines, both 2&4 stroke, on small wrecked out board legs. The biggest is a 13hp ohv out of a ride mower which is currently on the back of a 18' cabin cruiser.

The model will be powered by a small 2 stroke outboard.

Which brings me to the question of scale…

My intention is 2/3 scale

On with the build….

I managed to find the original half model and working drawings. (After sketching out the general form of the hull, I carve a small half model to finalise the design, and take all working drawings from that)

The ply side panels patterns are lifted off the model with a piece of card, which also confirms that the panels will fair smoothly around the hull.The model is then put to the saw to produce the frame shapes.

A few sheets of ply to get things started.

and the stem built up and rough cut ready for final shaping and pre beveling.

The stem is from three pieces to follow the curve. 'The tounge in cheek' joints are a little rough, but will be plenty strong.

Aj

[Ralph PinchParticipant @ralphpinch41762]

Looks good Amy Jane, this should be an interesting build.

Thanks for the info on the hard chine hulls, I have a lot to learn.

Good look with the build.

Ralph.

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Hi all.

Been hard at work, and have cut out the side panels.

I'm kit setting the hull at work, and then I'll take the parts out to my friend Lynn's place, (where I stay at the weekends) to assemble her. (The boat that is). Although I managed to negotiate building model boats in my spare time at work, this one will be very much in the way.

I took the side panel patterns off the half model before cutting it up. I then traced around my card pattern, and dimensioned it.

The vertical lines are the frame spacings, measured from the bow. The lower horizontal line is the sheer, the upper the chine. the sloped line is the transom.

this is transferred to the 7mm radiata pine ply.

The upward sweep in the chine at the transom is the result of carrying the width well aft, then quickly sweeping in to a narrow transom.

Scaling off a half model isn't super accurate, and a few errors showed up, but they were obvious, and the plan was amended to suit.

Due to the length of the sides, two joins were required.

This is my preferred method.

All the three panels are laid out end to end, but over lapping by a few inches and marked. The side pattern is then drawn out. A straight datum line is struck down the middle of the panel. The sheets are then separated, and the panels cut. One side is then used as a pattern for the other. The panels are then laid back together end to end and over lapping. A wiggly line is then cut down the length of the overlap with the jig saw.

The panels are then joined together with a butt strap of the same plywood behind.

(Making sure the datum line is straight of course!)

This method gives a much stronger and fairer butt joint than just a straight joint would.

The first frame made up off 3/4" ply. (used to be my bench top, don't tell the boss!)

All the frames will be made in two halves, for economy and easy transporting. The joins are cross halved, but not yet glued.

These ply web frames are strong and light, just the thing for any boat with pretensions of planing.

Amy j

Edited By Amy jane September on 15/08/2015 09:14:36

[IAN_IParticipant @ian_i]

Hi AJ..

Great start to the build..

Look forward to your progress..

Are you sure you have enough , plywood on the top of the car…lol

Best regards,

Ian

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Hi Ian

Thanks for dropping in

Might have to get some more ply, I keep cutting the stuff that I've got into little pieces!

[BanjomanParticipant @banjoman]

Hello Amy jane,

When you say that you intend to build to 2/3 scale, do you mean in the sense of 1' full size = 8" on the model, i.e. 1:1.5 scale? If so, that'll be one heck of a model if, as you say, the original was intended to be 30' long, as that would make the model 20'!

"Impressive" and "audacious" are words that spring to mind!

/Mattias

[IAN_IParticipant @ian_i]

Hi AJ..

>>Might have to get some more ply, I keep cutting the stuff that I've got into little pieces!<<

Is that to relieve frustration… or making fire wood ?

lol

Ian

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Good evening Mattias.

Well reasoned good sir! I was waiting for some one to bring that up. Yes the model is 20'x5' and will be powered by a 8hp outboard.

Many would say 'audacious'

Hi Ian

A bit of both I'd say! (nothing to do with cutting things the wrong size….)

On with the build.

All the frames are cut, 7 in all.

And the transom frame made. Because the ply edges don't take kindly to glueing and nailing, I've framed the transom in solid timber. I don't know what timber it is, (packing crate stuff) other than being a temperate softwood. Maybe Scandinavian pine or spruce?

Prior to assembly. A fair bit of marking and cutting, but strong construction.

Screwed to the bench until the glue dries. I'm useing my home made glue for all but the most important parts, as I now have confidence in it.

Once dry, I'll run the jig saw around the inside to clean things up. The ply skin will go on once the boat is assembled, as it will make fitting the chine logs much easier.

Aj

[ashley needhamParticipant @ashleyneedham69188]

AmyJ. Is the installed control gear going to wear a skirt? Ashley

[Bob Abell 2Participant @bobabell2]

Amy

I like the basic construction of your formers…….They are really well thought out

Definitely, fit for purpose

Do you live on a desert island…..btw?

Bob

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Good evening all

Hi Ashley. Suffice it to say that no one will have any complaints about the realisim of the crew figures!

I'm not actually building this for my self, it is part payment for a cabin cruiser that I bought off a friend. (I will have to give it extensive sea trials before I hand it over first of course!)

Hi Bob, Thanks for your comments, they mean something.

I Think I'd do well on a desert island! My policy is only to buy what I can't scrounge or make!

Aj

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Hi all

The transom frame is done….

The shelf forms a motor well, in addition to adding much strength and stiffness. (And a good place to bleed out that freshly caught kahawai.) I've designed the hull to take a maximum of 25 hp, even though I'll only be using an 8 hp outboard, so the transom has to be made to suit.

The acid test for how well my joints are made is when I put the jig saw through them , to trim to shape.

will do…

All the frames are pre-beveled, ready to wrap the sides around. The bevels are taken straight off the half model

and transferred directly to the frames…

….which works out to be fairly accurate.

A pile of assembled frames.

The panels of one side joined up.

[Andy CParticipant @andyc56856]

Hi Amy J

That has got to be one of the largest radio controlled boats ever. Bob's Lady J will look tiny against her. Have you thought about how you will transport her?

Andy

[shipwrightParticipant @shipwright]

Andy,

I am guessing from comment made at the start of Amy's posting dated 22/08/2015 23:16:20 that this is a boat that people sit in (ie not a model boat).

Ian

[Author]

Posts