Build own shell

[Lifeforliving]

Hi all thinking about build my own boat. For weekend and leisure cruising. Thinking about a 21 foot nb. Experienced in the construction industry. (Heavy plant) capable welder. qualified chippy. However haven't got a clue where to start. Anybody else built there own shell.  & Could Give me an insight on your experience. Cheers Dave ?

[dmr]

A few have done it, some from a kit of precut steel, others from scratch, some very good, some not. Its not just about the welding, have you got a good eye for a pleasing shape of boat? there are a few pig ugly DIY shells on the cut. You will need to form some pleasing compound curves to make a good boat.

 

.............Dave

[TheBiscuits]

21 minutes ago, dmr said:

some from a kit of precut steel,

That's the way to do a one off.  Tab A into slot B and weld it watertight.  The kits obviously cost quite a bit more than uncut plate, but the results are much better than some of the make-it-up as you go along builds.

 

 

[howardang]

45 minutes ago, Lifeforliving said:

Hi all thinking about build my own boat. For weekend and leisure cruising. Thinking about a 21 foot nb. Experienced in the construction industry. (Heavy plant) capable welder. qualified chippy. However haven't got a clue where to start. Anybody else built there own shell.  & Could Give me an insight on your experience. Cheers Dave ?

Welcome to the forum and I am sure you will get lots of advice. My initial thought is that a 21ft steel narrow boat is really, really small. It may help to clarify your plans tohave a look at a few boats for sale at brokers, and also on some  of the brokers web sites. You don't mention how many people will be cruising with you but even with two on board such a small craft I think the enthusiasm may fade quite quickly.  Have you thought about buying a shell and fitting it out yourself. You say you have the skills, but please give some thoughts to levels - nothing is square in a narrow boat and you need to allow for some awkward shapes.

 

Good luck with your project.

 

Howard

 

 

   

[MtB]

17 minutes ago, TheBiscuits said:

That's the way to do a one off.  Tab A into slot B and weld it watertight.  The kits obviously cost quite a bit more than uncut plate, but the results are much better than some of the make-it-up as you go along builds.

 

 

 

I agree. Designing the shapes and cutting them out of sheet steel is the hardest part. If you can find a kit of pre-cut sheets, this is the way to go.

 

Sam Springer used to sell kits of pre-cut shapes to build your own NB with a Halfords welder. Always regret never buying a kit and building my own back in the day. Too many other things going on tho!

 

 

 

 

 

[RMK]

Hi Dave

 

25ft https://www.gumtree.com/p/boats-kayaks-jet-skis/25ft-steel-narrowboat-lady-jane-bss-good-dayboat-or-project-£10000-ono-07388-551593/1319708335

Scroll down page a little.

 

This 25ft is a good example, only thing they have done is extend the cabin, which means folded can only go so far, see below. But it isn't too hard to do the extended cabin.

Probably looking at a 17-18ft cabin so not bad.

 

There is one problem with a narrowboat, I'll come to that soon.

 

Cabin tops can be folded in out of 4x2 cut to whatever cabin size you want (3.34 blah blah, depends on you). Hull sides folded too 2.5x1.2 to incorporate gunnels.

Arse end,, sorry 'stern'.. ;) can be rolled if you want round, could go easy and square it off, but round is easy so don't cut the corner. Bulkheads are common sense as are most things steel narrowboat, inc strengthening etc. Rolling the 1"x1" box section for the roof supports (I'd say 3" rise will do), is not a problem. It certainly isn't rocket science by any means, but if you have fabrication skills, then it should be possible.

Welding wise, dye pen 2' up from the base all welds, 'V' that base and do the best job on it plenty of it (you understand what I mean by that).

Handrails etc, just bog standard will do (cruiser style) round or box either.

 

Now the problem.. it's the Bow, this is not easy and can make or break your boat, bow & returns on a nb can be a nightmare for those not familiar, so beware.

 

Building your own will save you a small fortune and not many shell builders would even bother with a shell build at just 25ft.

 

Just keep asking if you decide to go ahead.. :)

[Lifeforliving]

Cheers guys great tips ?

[blackrose]

7 hours ago, RMK said:

 

Building your own will save you a small fortune 

 

Really? Even after you've factored in a cost for all the time spent building it? The true cost has to include something for the labour even if the person doing it is retired.

[Murflynn]

I have built about a dozen boats, steel, GRP and wooden, from scratch, from 12ft long to 43ft long.   

 

As a crinkly old git my advice is that if you want to do it because the building activity will give you personal satisfaction, then get on with it, and good luck.  However if you would like to stand back and admire your boat for many years to come, or expect to sell it in the future whilst covering your costs, then don't do it.

Edited July 18, 2019 by Murflynn

[blackrose]

If it's about personal satisfaction then fair enough. But if it's about reducing cost, then buying an old Springer water bug, replating it where required and fitting it out might be cheaper than building it from scratch - and you'd still get some satisfaction from doing the work yourself.

Edited July 18, 2019 by blackrose

[NB Esk]

I built my own 55' tug style.  Did it to my own plans and worked mainly at weekends and in fair weather.  I did find it took longer than I originally estimated but then I did start a little late in life.

If I could turn back the clock I'd probably have done things differently, would likely have bought a sound boat that needed restoration and gone that way.  Immensely satisfying but don't underestimate the amount of work.

The only other thing I'd say, as the majority of work is in the bow and stern, do think carefully about the wisdom of building a "short" boat.

 

A mid build photo...

 

 

[NB Esk]

11 hours ago, Lifeforliving said:

Hi all thinking about build my own boat. For weekend and leisure cruising. Thinking about a 21 foot nb. Experienced in the construction industry. (Heavy plant) capable welder. qualified chippy. However haven't got a clue where to start. Anybody else built there own shell.  & Could Give me an insight on your experience. Cheers Dave ?

 

Forgot to mention in my above post, there's also a rule concerning self built boats that you may not be aware of.  In the case of a one off self build, it's illegal (not absolutely certain that's the correct term) to sell the said boat within a period of five years of build date.  May be worth checking and taking into account.

 

 

 

[Murflynn]

1 hour ago, NB Esk said:

 

Forgot to mention in my above post, there's also a rule concerning self built boats that you may not be aware of.  In the case of a one off self build, it's illegal (not absolutely certain that's the correct term) to sell the said boat within a period of five years of build date.  May be worth checking and taking into account.

 

 

 

not quite.   it needs an RCD certificate that can be self-certified provided:

- the boat complies with the relevant BS/ISO/EN standards

- you have the skills to do the structural calculations for the hull scantlings and the stability

- you can produce proper technical documentation 

 

alternatively you can pay a marine surveyor to do the documentation it for you, and to advise you where the boat falls short of the requirements.

[MtB]

And a second point. It may be illegal to sell a self-build with no RCD within five years but it happens, and no-one has ever been prosecuted for it as far as I can determine, so the risks are low.

 

Trading Standards have to mount the prosecution, and they are too busy with more important stuff. Nobody cares about RCD except the type of boat buyer who likes having rules to follow.

[David Mack]

10 minutes ago, Murflynn said:

not quite.   it needs an RCD certificate that can be self-certified provided:

- the boat complies with the relevant BS/ISO/EN standards

- you have the skills to do the structural calculations for the hull scantlings and the stability

- you can produce proper technical documentation 

 

alternatively you can pay a marine surveyor to do the documentation it for you, and to advise you where the boat falls short of the requirements.

And the same applies if you buy a shell and self fitout. The shell builder is responsible for producing the documentation for the shell, but you are responsible for the boat as a whole.

[NB Esk]

31 minutes ago, Mike the Boilerman said:

And a second point. It may be illegal to sell a self-build with no RCD within five years but it happens, and no-one has ever been prosecuted for it as far as I can determine, so the risks are low.

 

Trading Standards have to mount the prosecution, and they are too busy with more important stuff. Nobody cares about RCD except the type of boat buyer who likes having rules to follow.

 

I think that more or less sums it up.  I was more concerned with the forming of my own plate than RCD regs, so mine was built to BSS requirements.

I too have not heard of a prosecution under the five year rule and believe it would probably only come into play if an unscrupulous builder tried to foist sub standard shells on an unsuspecting public.

 

 

[MtB]

13 minutes ago, NB Esk said:

I too have not heard of a prosecution under the five year rule and believe it would probably only come into play if an unscrupulous builder tried to foist sub standard shells on an unsuspecting public.

 

 

Yes I think that is it exactly. Anyone setting up in business flogging lots of non-RCD shells will get stopped by Trading Standards but ordinary Joe who builds one boat a decade has little to fear.

 

[Mike Adams]

A 21ft narrowbat doesn't make much sense to me. You will probably need an outboard to save space. Much better to look for a fibreglass boat or even something like a water rat. You can put it on a trailer and go anywhere. They are as cheep as chips.

[RLWP]

9 minutes ago, Mike Adams said:

A 21ft narrowbat doesn't make much sense to me. 

 

Oh, I don't know. Ten foot of bow, eleven foot of swim and you'd have an amazing boat

 

Nowhere to live mind, but wow she would swim well

 

Richard

[Mike Adams]

30 minutes ago, RLWP said:

Nowhere to live mind, but wow she would swim well

Built like a 'standard' narrowboat with a steel top would probably tip over at the first bend unless it was deep in which case it would be a slug.

[RLWP]

1 minute ago, Mike Adams said:

Built like a 'standard' narrowboat with a steel top would probably tip over at the first bend unless it was deep in which case it would be a slug.

OK, so we can omit the steel top then

[RMK]

9 hours ago, Lifeforliving said:

Cheers guys great tips ?

As you may have deemed from my post, or not perhaps..

 

It is a big saving to make your own (big saving), provided you use your own labour. You seem to be related to the fabrication industry, I imagine you pay reasonable prices for steel.

However, it is fine for a builder to produce sizes and details at the drop of a hat, as I did in my post, plus it would be built in short time, lets face it, it would have to be, there would be no money in it.. ;)

 

It's not to be taken on too lightly.

 

If you do want to go ahead 'pm' me when your ready, but not before.. I'll gladly provide sheet sizes,  fold details, simple plans etc, even the build process that will get you from the stern to bow pretty fast. Bow wise, we can give written/plan instruction, but even with that, it ain't easy.

You'll need a short swim and bow for a boat that size (as in the link I did), a little twin cylinder diesel (inboard) although they're not cheap if your not in the trade, plus bits (I wouldn't help with those), but there are plenty of places about.

 

My advice, just think very carefully first, it would take us day's (literally) to build the one you see in the pic, but on your own without the facilities, then it's very hard work.

 

Oh, and 25ft is the shortest you'll want to go, even that these days is too short to bother with steel wise (imo). The middle bit is easy and cheap (comparatively), so think on. Longer perhaps..

 

Regards.

RMK

[Guest]

I always liked this short narrowboat. Not sure of the length.

 

 

 

[blackrose]

47 minutes ago, catweasel said:

I always liked this short narrowboat. Not sure of the length.

 

 

 

It's built like a 'standard' narrowboat with a steel superstructure but it's not tipping over?

[John Hartley]

Myself and two other guys built our first steel narrowboat. 45 ft from a set of available plans. The local steel stockholder did all the bends for us [gunnels]. It took the three of us 4 years and one week. Easter is a movable feast. We worked every Sunday and 2 evenings a week, it was hard graft but we enjoyed every minute of it. Go for the biggest shell you can fit in the build space, because all the work is in the stem and stern. the bit in the middle is much easier. When completed the insurance value was £42,000 the actual cost to us was £12,659, less our hours worked. We did it for love not profit. We rebuilt an engine for it but had to purchase a new gear box and propeller. We bought the correct stainless steel and turned our own prop-shaft. When the shell was completed we filled it water to check it did not leak. It did, about an egg cup full over four days. Its a huge undertaking, do not underestimate that but when you sail away for the first time its a huge satisfactory feeling that last as long as you own it.

If you need any help I can give only too happy to help.