Building an Instant Boat

[marshmat]

I've decided that I'm going to build this boat: https://www.boatdesigns.com/products.asp?dept=183 without fiberglassing the entire exterior.

Hang on a sec, before you say that. You could build that, yes. And your budget sounds about right, if you don't go too fancy on it.
But DO NOT skip the fibreglass! Stitch-n-glue as a method of construction is dependent on the combination of curved plywood panels, taped seams and the continuous exterior sheathing for its success. The glass sheathing is not just there for abrasion resistance- it is a structural component of what is essentially a nearly frameless, semi-monocoque structure. The boat will still float without it, but will be substantially weaker than designed and will not come close to the designer's intended lifespan.

My advice- Go for it, it'll be a fun, relatively simple and quick build that you'll be pleased with in the end. But do follow the designer's plans and directions when it comes to structural matters.

[ironmetal250]

You're probably right... so the fiberglass will add about 100-150$ to my bill?

[kengrome]

I thought you wanted to learn how to sail???

[ironmetal250]

Originally Posted by kengrome

I thought you wanted to learn how to sail???

I do... as I said in an earlier post, if I build a small boat first, my parents will give me all the money I need to build a Minuet (15' pocket cruising sailboat)... I decided to build the RowMe because it seems like it will be built the fastest and still have some use to me, allowing me to get started on the Minuet before winter kicks in (hopefully)

[ancient kayaker]

You mentioned a canoe or kayak as a first boat earlier. That would teach you most of what you will need to know about building in ply without burning your budget. It will also take less time to build, less space to store and doesn't need a trailer. I have built several from scratch for around $100 each in about 40 hours per, plus plans.

I don't find it necessary to use 'glass, I keep the weight down so I can carry the boat easily and not bang it about. You can get by without it on a canoe as enough stiffness is provided by the gunnels and chines. also an unglassed canoe is easier to cut up and toss when it comes time ...

[ironmetal250]

Been a while...


This is my boat as of right now.


Boat with the seat panels placed inside


Did I do the epoxy fillets right?


Transom knee, breasthook, and oarlock uprights


Close up of the inside of the bow


Transom connected a bit unevenly (this is on both sides)... hopefully this won't be a problem when I put the knee in


Bow seat doesn't really fit on all that well...


...on one side it doesn't even overlap the seat cleat... maybe I could put a block of scrap plywood there?


Finally, the sheers... I haven't even started working with these yet and I dread doing so... I've had nightmares about it.

[ancient kayaker]

You're getting there. The first one a learning, and maturing experience. Gret feeling huh? I see you managed to work inside after all. As far as the seat is concerned, if I have uderstood the photos correctly, the best thing to do at this stage would be to cut a new one that'll fit properly, since the seaat looks to be part of the hull structure; not a place where you'd want a weak joint.

[ironmetal250]

OK, thanks for the advice. Hopefully I have a piece of ply big enough to cut a new piece.

[ancient kayaker]

A piece of cheap ply that fits well is better than a top grade piece that doesn't.

[Tug]

http://www.boatdesign.net/gallery/sh...g/ppuser/22042

One of the instant boats..
Cheers
Tug

[Stumble]

I would really recommend removing the bow piece and makeing a new one. The bow takes a lot of shock loading while going upwind, and the fact that the fit is that far off would worry me. But instead of doing one from plans, place a piece of plywood cut to the rough dimmensions plus about 1 inch over the sides, and trace the outline onto it. This will give a much better fit that exacally followes the lines of the hull as opposed to the plans.

You also seem to be using a thicker layer of epoxy than you really need. I normally use a large radius smoother for this type of work, say a 1" or something like that. If you are using the epoxy to fill gaps, I would recommend you do it in two steps. The first to fill the gap and the second for the bonding. By filling the gap first it makes it a lot easier to get a clean finish and ensure there aren't any voids (think trying to fill the transom gaps), then you do the bonding step which is now easier since you can concentrate on getting that part right.

Otherwise it looks like you are doing a nice job! Congrats on your first boat build.

[PAR]

The problem with this hull is it's warped. This is why your bow piece doesn't fit and there are huge gaps at other locations.

The hardest thing about building without a jig, is keeping the darn thing reasonably square as it get it's pieces goo'd in.

Constantly measure the distance from the corners of the transom to the bow, insuring they are the same and also that the lower corners of the transom are the same height off the floor. This can be made easier if you screw the boat down to a "strong back" once you get the panels twisted back to where they belong.

You're going to have hell to pay come time to smooth out those fillets. Had you worked "clean" and removed all but just the actual fillet, you'd have seams that required very little sanding and smoothing. As it is, all those drips and puddle of cured goo will be painful to say the least to remove and smooth out.

Everyone has to learn this and if you're like most of us, then it'll be the hard way. Once you start cleaning up those fillets, you'll see what I mean and you'll be much neater then next time you make some.

As for the bow piece and other elements, don't pre cut them. Cut them to fit, because the boat has some twist and distortion in her, so pieces cut to the dimensions on the plans aren't going to fit. Always "build to the work". After you gain some experience, you can build much closer to the shapes found on the plans.

As a matter of fact, I would stop gluing in pieces at this point and start cleaning up those fillets. It's a lesson you need to learn if you're to make the job go easier further on in the build. Buy lots of sand paper.

I would also think you need to tape some of those seams. If you install parts over previously filleted seams, you may have access issues when it comes time to tape up stuff.

So, stop there, square up the boat as best as you can. Screw in some braces to help keep it square. Clean up the fillets that get taped, apply the tape, then start "fitting" the next pieces, knowing what you're about to learn about fillets.

What you'll learn is once the fillets dry, they're a bear to sand smooth, so you'll try to make them much smoother next time. Also apply the tape as you do you fillets. It saves time and makes smoothing things out easier and is a fair amount stronger too.

Keep stroking it, you're getting there. It's looking more like a boat now.

[ironmetal250]

Thanks for the advice.

What do you mean by a "strong back" and braces? What should I use for braces and where should I put them?

[Manie B]

hi Ironmetal250

congratulations on your build

it is absolutely fantastic how far you have progressed

what PAR has said is 100% correct

from what i can see is that your putty mix was too watery - it should have been much thicker. it is important that you take great care with your filleting of seams -it saves a huge amount of time and hard work later.

hang in there for a couple of days - i am going to do my next lot of fillets and TAPE this coming weekend and i will take a comprehensive lot of photos on the mixing and bagging of the putty and spreading

all this will be posted on my miniCAT5 build

MiniCAT-5

as you can see from this pic it is easy and saves a lot of work later

but once again

GO MAN GO

i am proud of you even if i am on the other side of the planet

[Manie B]

i have looked at your pics now very carefully

your boat is already very solid - it is unlikely that you would be able to twist or bend the boat. Dont worry it is all good DO NOT cut out or remove ANY parts

everything can be fixed and cleaned up

the boat will be a lot of fun

are you working with epoxy ???

please post pics of ALL your mixing and fillers