building vs buying...

Thanks Jeff...im guessing the labour is the monsy saver here. but sadly im actually seeking a specific vessel. I am hoping I don't have to compromise. I might have to. but ill keep trying until I know its a lost cause. its why im asking about building- but read my post to Brian on here- if moving costs get expensive too..it add thousands to the price of a used boat ...the way I see it is this:

the truth is I am getting some money form the sale of my home.
but the sale might take 1 month or it might be 5 years before it sells.

in the meantime- I can build a boat and start investing the money into it.
if I wait and the place sells -then I have already invested a good portion of my money in a new and sound hull. however either way -whether I buy or build- its could end up being 5 years.(hopefully not!) but if it does -at least I know the LONGEST ill be waiting to be on the water is max- 5 years.
so if I build- I am seeing progress. I am getting the exact boat I want...and I am investing as I go. but that's just what I think. The vessel in question- my 45 st tug- I wont have the fund till the place sells. so it may be gone and trust me- I have looked for this vessel everywhere. and none are to be had for what I can afford. due to the machinery included which I do not need.

the boat could be made out of other materials- such as frp,sheathed strip, FAL FC core or even cold-molded- since its not a full work tug but I like the stiffness of steel..

 

That 21 percent was for a "compound" or double-expansion set-up ? The old steamships were triple expansion, at least some were. But 2.44 tons of coal per hour is chewing through the $ at today's coal price.

 

stiffness

I did have a question regarding materials -- if a vessel is designed in steel, and has a given displacement to the waterline- it must then weigh the same to the waterline regardless of material correct?
so does it matter what material is to be used? I get confused on this issue since it is generally understood that steel is a stiffer vessel in a seaway. but why would it be so? im guessing because the rest of the vessel is heavier? I.e. the topside and wheelhouse would be heavier and resist rolling ? But then I think how can this be since - the entire vessel must equal the displacement. ie. 17 000 lbs. is 17000 lbs.
so why would steel make it any more stiffer than say a ballasted sheathed strip hull which is quite light as a material? I have even heard the opposite argument that the lighter a boat is the better it handles due to the fact it can be ballasted better*
clarity on this would be wonderful...
*(see T. McNaughton's scantling rules for sheathed strip)

 

I don't know the exact figures - hut there's no question that its many times less expensive to feed a coal train than a diesel one...

...unless I missed something somewhere... coal is still cheap regardless, and less than diesel.

and a train probably uses a hefty portion of that in fuel weight per hour.

I still maintain it would be less expensive and better to run steam - the downside being - you don't push a button and go... so some fuel gets used up while building steam. steam is still viable with todays modern technology.

 

Stiffer, as in resistant to pitch or roll, or more rigid structurally ? Certainly the latter would be true compared to a creaky old timber vessel that "works" in a sea.

 

I think you need to keep one other thing in mind here. The boat you build should have a reasonable market place down the road, as likely you or your heirs will need to sell it for various unforseen reasons.

So while you are thinking of what you want specifically, what might have a good potential for resale in the market??

A steam powered tug boat is not going to be that marketable in my opinion. That canal-trawler concept will, in my opinion,....even in a partially completed state.

 

sorry I meant to be clear- stiff as in a seaway resistant to roll. i.e. not tender. (form stability)Thanks!

 

Yea your probably right about that- the only disclaimer being I live on the great lakes so it would need to be pretty seaworthy, not sure if a canaller would be a good choice for someone on the GL's.

also wouldn't it be fairly easy to repower-(yea not cheap!)? they could add the diesel? of course I have no kids and don't plan on having any. so I wont have any real heirs. Resale is of relative importance to me only because I will get my monies worth out of it.
But- isn't steel pretty good resale? I know fc isn't but epoxy sheathed strip? or frp? aren't they sound investments? The other material I thought of was a really thick laminate of frp. its an easier build than steel and faster too- even with a male plug. would be kind on my back. and frp seems to hold its value ?
I have seriously toyed with an frp hull in this shape- it also eliminates the round bilge issues- I know you are advocate of chined hulls. I love George Beuhlers thoughts...- he loves Chined hulls too...and someone here- and I apologize if I forgot the persons name on this thread- mentioned chined hulls may even be more smooth through the water, but I really just wanted to keep the 45 st tug to its original design parameters...

 

The same hull form, of the same displacement, and the same center of gravity, will have the same transverse stability no matter what it's made of. In reality an all steel (unballasted) boat will have a higher VCG and less transverse stability than a strip-planked ballasted version of the same hull (both floating at the same waterline). Longitudinal stability and pitch damping is another more complex discussion involving radius of gyration.

 

Thaaaank you Tad!!

 

That should read "build a boat and start pouring endless money down a rathole"......

PDW

 

Important if you are unable to complete it (sudden new health issue, etc), and/or if your wife tries to get some money from it should you not out last her. I'm 70 and this has entered my mind should I start one of these new builds I have in mind for her and I to live on. I don't want her stuck with a problem sale as much as I can avoid it.

I don't think a partially completed frp vessel is as easy to sale off as is a reasonably well built steel one. Factories build frp boats, individuals build steel.

Not true, steel is easier and quicker.

Actually I'm not a fan of chine hulls necessarily, as I've had very little experience with them,....dealing primarily with multihull vessels in my past.

But I do think the hard chine hull is the way to go for a more stable hull, and particularly in a slow displacement speed boat. Here is a real simple explanation:
http://www.trawlersmidwest.com/pdf/article%2019%20buying%20a%20trawler.pdf
...I'm sure you could find much more discussion on this by googling "hard chine boat"

And the hard chine or dbl chine vessel would certainly be easier and quicker to build in steel, in fact there could be a lot of relative flat plate surfaces that would go together rather quickly. And this hull form would displace more than the soft chine vessel (in identical size vessels), so a slightly higher plate thickness could be utilized, and that would require a little less inside framing.

 

Wrong. Sorry but you simply are wrong.

When was the last commercial steam locomotive built and if steam is better than diesel-electric, why don't trains have steam plants?

Here in Australia we have some of the biggest coal deposits on the planet, we export billions of dollars worth hauled over custom-built railways owned by the mining companies. They can use whatever they like, coal to power the trains is effectively free and they have 100% control over what rolling stock they buy & run.

Guess what, there isn't a single steam powered locomotive running on any mine railway anywhere in the country. That tells me someone has done the figures and diesel-electric is more efficient.

I spent a lot of time on oceanographic research vessels. Some of our voyages were constrained by range and we could carry 2 megalitres of fuel oil. Nobody is building big steam driven shipping because it's more efficient, because it's not.

You want to run a steam plant because you want to run a steam plant, fine. I have friends who build live steam locos and others who want to build steam powered launches. I don't try to talk them out of it, might build one myself one of these days. However it seems that you have no plant on hand, you don't have the tooling or skills to build one of any practical size and I expect the purchase price, with boiler etc etc is going to considerably exceed the price of a decent diesel engine.

Look, I'm not going to spend a lot of my time doing research on the net etc to disabuse you, this is shaping up the same way as did the ferrocement arguments. You make blanket statements based on how you wish things to be and eventually the reality of engineering materials sinks in and you come to realise you're wrong.

So basically do what you like but I can't be bothered reading & commenting on fanciful claims about the efficiency or otherwise of steam plants and engaging in endless argument while reality dawns slowly on you.

As for that tug, if you can get the price down a bit and the hull isn't a metal sieve held together by paint, buy it and get on with the refit. You'll never build cheaper.

PDW

 

1. I never said I was running steam because it was more efficient- 2. never said that steam WAS- what I said was-- and go back and read it- that steam was viable as an alternative and that it was cheaper- I also stated it had drawbacks...
oil companies dictate everything- so this is my OPINION on why steam is not looked at more closely. as the technology is there- the infrastructure is not..


so far I think I've not heard one positive comment from you other than trying to, as you say, "disabuse" my statements. you must spend a lot of time trying to resolve my "blanket statements"...

my suggestion: try supporting someone's goals for once. not try to contradict and disprove everything they say...

Whatever- perhaps -I am like you and don't have the time to argue as in the ferro cement debate-I never thought I was "wrong" as you suggest-nor was I. ever "wrong"-

truth is - for your kind- I just placate you to stop you from once again trying to disprove me that so can keep believing you have everything figured out more than I do. and that no one could be right other than you..that's fine- its your trip not mine..
as for the boat- your probably right about it being the cheapest option but if cheapest was the best- why then did you build yours? I like the idea of building one. In fact try to find an army st tug- in steel- that is sound and is selling for under 70k.

You can take this blanket statement to the bank- it will by far be cheaper to build a new hull for 40k than to buy a used one with all machinery and such for 70k. so what if it costs the same in the end? who cares? building a boat is rewarding...as you know.

 

(7) Single cylinder double acting steam engine 20 hp, cylinder dia 140mm x stroke 116mm, US$ 2400/

Boiler- 90 sq ft yarrow style... 400 psi working pressure- 4200.00