dinghy rigidity

[marc gogarty]

Good Afternoon,
Congratulations on this forum, following advice posted here has already saved me hundreds of pounds
I hope that as a new forum contributor it is ok to dive straight in with a question....

I have a marine ply enterprise dinghy. I want to remove the foredeck and bow tank including bulkhead.
I am certain that I will need to reinforce the hull.
I plan to step the mast on the keel.
This boat is used for light sailing on the thames. no racing

This question will not appeal to dinghy purists, sorry.
My reason for trying this customization is that I would like some
where to sit comfortably or put a passenger.
I have a full compliment of flotation bags including a bow tank bag
I cannot afford a sailing skiff or anything like a self build...i had to build the wooden gunter rig in my living room...
I have searched the web to no avail trying to find someone (living)
who has done this.
is this an insane plan?

[Hwyl]

Yes it's insane, your passenger would be uncomfortable and wet. Your boat would lose strength, the space you gain would be inconsequential because you'd still need support for the mast.

If you need more room get a Wayfarer.

[floatingkiwi]

Post some pics mate.

[frank pedersen]

I agree with Hwyl, but I know a Wayfarer is costly. Along with destroying a good boat, having significant weight forward of the mast is apt to invite more time swimming than you would like.

Frank

[mmd]

<lol> Gareth, you don't mince words, do you? Sage advice, emphatically delivered...

[DGentry]

Insane, well, maybe not. But . . . .

It's a small boat. You can't really put a passenger up in front of the mast, and if you managed to, your boat would be balanced poorly, in addition to all of Hwyl's considerations.

BUT you say you've built a gunter rig - is it for that boat? With no jib? If you have decided on a cat rig, and plan to move the mast way forward, then your plan for opening up the interior might work. Lots of 13' dinghies have cat rigs and open interiors - see the thread on best 12 sailboats: http://www.woodenboat.com/forum/showthread.php?t=106292

However, my suggestion would be to leave it alone and sail it as is . . . that design has been around for a while and is successful. Possibly, if you just had to, you could widen the side decks to make it more comfortable to sit on . . . .

Good luck!
Dave Gentry

[James McMullen]

I would like somewhere to sit comfortably or put a passenger.

Ahead of the mast is not that place. I agree with the rest of these surly, opinionated louts. Don't do it!

[rbgarr]

I used to sail Enterprises and would consider it a punishment to be banished forward.

[Thorne]

Post some pics of the new rig you've built, and tell us how anyone could sit in front of the mast with the Enterprise class jib sweeping that area.

As above the boat isn't balanced to handle much weight forward, and you'd need a mast partner anyway - aka: horizontal brace across the boat at gunwale level.

You could try flying a smaller jib, or one cut higher in the back, and removing the V-shaped splash guard on the foredeck -- that might allow someone to sit or lie on that deck when drifting along in light winds.
http://www.sailingnetworks.com/images/photo/44091.JPG

Some pics of an Enterprise dinghy and interior -
http://www.sailingnetworks.com/design/pictures/d-enterprise

Years ago I also "repurposed" a similar wooden racing daysailer for relaxed trips with the wife, nephews and nieces, dog, etc. But the 14' Blue Jay had a jib cut higher in the back so folks could actually stretch out on the little foredeck (such as it was). I also built a small motor mount to use with my smelly old Seagull.

Other than adding the motor mount and oarlocks with a temp thwart that could go across the boat for occasional rowing, I didn't make any structural changes to the boat. So you might be able to get what you want with just a sail change. Please post pics of your sail rig all up on the boat if possible.

http://farm4.static.flickr.com/3104/2608763189_0f51d4ac87_o.jpg


Here's how to post photos on this forum:

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TROUBLESHOOTING:
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[marc gogarty]

Thanks Mr Thorne for your time and encouragement

the mast is to be stepped on the keel
it will be supported by the shrouds
which will still be attached to the gunwhales/bow plate
the jib rigging will therefore be unaffected
the mast will pass through a new thwart(at same level as two part
thwart which bissects the centreboard casing
the idea of the whole project is to open the boat up.
I always sail single handedly so no-one will be up-front under sail-getting in the way.
I havre already installed gunmetal rowlocks+mounts from classic marine.
The gunter rig is sitka spruce with high peak gunter saddle(classic marine) replacing the aluminium original so that i can get under bridges.

this next part is not for you Thorne.

As for 'ruining' a good boat i think thats a rather unhelpful comment and of course if I could afford a wooden wayfarer then i would not have sent my original question - and i simply will not sit in a plastic bath thanks. Over 30,000 enterprises have been produced and I think that a boat that is being enjoyed regularly is better than yet another old ent rotting away in a dinghy park looking 'correct'.
This is a very high sail number 19777 so it is not a vintage boat.

[P.I. Stazzer-Newt]

Your boat, your dream -but you might want to do the stress calcs and balance calcs - BEFORE you start cutting timber.

Mast foot compression loads?

[marc gogarty]

thats more like it!
thanks

[DGentry]

OK, just curious now . . . how will opening up the interior make any difference, at all, to you as a singlehander? I just can't see any benefit, whatsoever - your position when sailing won't change, regardless of whether you have a foredeck or not.

Really, I'm not denigrating your idea, I'm just dense - why do you think removing the foredeck will be a benefit?

[marc gogarty]

in an ent there is a lot of wasted space, for example between the aft thwart and the transom - in many other dinghies this area is utilized as an aft flotation tank or useful cubby or both (just like the wayfrer yes - "2500 upwards for grp £4000 upwrds for wood.)
I have plans to install something similar.
the actual business of sailing requires use of the area between aft thwart and
mast.
The area from the mast support strut under the aftermost edge of the fordeck to the bowplate is the real estate i have my eye on. Somewhere to be comfortable when not rowing or sailing. Perhaps with a canvas tent bent to cleats under the rubbing strake.I want to have somewhere to brew a cuppa and catch up on Margaret Dye. The mast will stay in exactly the same place - the gunter rig when fully extended carries is the same height as the original alu mast. Gib on forestay up to mast band (along with the shrouds+topping lift).
a custom three reef cruising sail. There are no waves on the thames apart from those caused by three tier gin palaces.

[rbgarr]

My recollection of the Enterprise is that a person's weight up in the bow makes the boat very tender and tippy due to the sections of the hull there. They are tender enough even aft where they have flatter sections.

[marc gogarty]

quite....good point - something to watch.
i intend to leave part of the fordeck (the same width as the rest of the deck - with perhaps coamings unless they look like fouling the gib)
ents do have that reputation for tippiness
Jack Holt finally conceded that it was PERHAPS slightly over canvassed as a design - its a hiking dinghy, yes, and not as stable as as GP14s etc (and of course the westerlys). If one does not take the p123 it is till quite a forgiving sail. But then you see a lot of helms cleating off the main sheet on a traveller tightening hard then wondering why they gybe so

[rbgarr]

I don't see how it will leave enough space to sit if you leave sidedecks forward. Your knees would be up under your chin. Good luck anyway.

[Tom Robb]

Question asked and answered.
The answer may be perceived as unhelpful but it was correct.
If you don't like the answers perhaps you oughtn't have asked.
The forum gets a lot of that sort of thing.
Good luck anyway.

[marc gogarty]

most answers show that the question was not read in its entirety
there were two helpful comments
the rest is just flaming
and not at all helpful
i will not be bothering this forum again

[Candyfloss]

'Bye Marc.

Hacking good boats around does not go down well with me, either.

[James McMullen]

. .. not at all helpful

Yeah! How dare you people not agree with his bad idea?



i will not be bothering this forum again


Good idea! There are certainly lots of other forums where people who know about the structural and performance limitations of small, wooden daysailers congregate.


Chill out, Mr. Gogarty. Everyone here was trying to be helpful. Pointing out that there's a cliff ahead that you're walking towards is not being a busybody--especially when you've just asked for directions!

[mmd]

marc, don't go away mad. In fact, don't go away. This place is populated with a bunch of folks who don't think that any given design should be messed with. Also, a lot of folks who believe - and encourage - that you can. Some express their opinions with finesse, others with a club. It's sorta like calling out to a group of teenagers on a street corner, "What time is it?" A few will yell, "Time for you to get a watch!"; a few will tell you it's a hair past a freckle, and one or two (who actually own a watch and can tell time) will answer your question. It's up to you to figure out who is who. And you may not like to hear how late you are for your next appointment.

To consolidate the answers you have received so far, the deck you want to remove is an integral strength member of the hull, used to not only support the mast, but to provide transverse strength to the gunwales as well. If you remove it, you must replace this lost strength with some other structure. This may cause the space you want to open up to be somewhat cramped for seating. With that caution in mind, have at it!

Oh, yes; we do appreciate pictures around here - it makes us (sometimes) look and think before we start to opine...

[marc gogarty]

thankyou thorne and mmd - you are obviously gentleman sailors
as for the karate kid (or is it ekky thump?)- can you come and paint my fence?
i have a yellow belt in chindogu

("sail across the channel in that Mr Holt, at night? you are insane")

[Hwyl]

You asked



is this an insane plan?

I answered


Yes it's insane,

If this is flaming and unhelpful then so be it.

You also mentioned passengers in the bow in your first post, then you backed off.

Your idea of the gunter rig for bridges is acceptable and a good plan as long as you are planning on recutting the mainsail.

I'd keep the foredeck, go with the gunter and use a boom tent for your comfort. You'd be re engineering the compression post as a tension post

Good luck and I never intended to be rude, your question was blunt and so was my answer.

[John Meachen]

As another former Enterprise sailor I would say you have the wrong boat.Two things it will not benefit from are extra weight aloft and extra weight depressing the bow.Your boat and your choice but from the list of work already done the choice has been made so why ask for other opinions and then get rather emotional when they are not what you would like?

[P.I. Stazzer-Newt]

Am I right in thinking that the Enterprise has a deck-stepped mast?

These folks might be interested.
http://www.cvrda.org/community/

[Hwyl]

Am I right in thinking that the Enterprise has a deck-stepped mast?



Indubitably

[P.I. Stazzer-Newt]

Thought so. - here's a view of one.
http://www.overystaithesc.org.uk/anim/nick02.jpg

If you whip off the deck and understructure - the stress realisation is going to get interesting.

[Peerie Maa]

I'd keep the foredeck, go with the gunter and use a boom tent for your comfort. You'd be re engineering the compression post as a tension post


Best suggestion yet. keep your weight were the waterplane is widest.
Convert the forepeak into stowage by all means, but not too heavy.

[James McMullen]

"chindogu" Well played, sir! I have hope for you yet.

[Candyfloss]

You obviously have plenty of opinions yourself Marc, that you are not shy about expressing. How can you begrudge others theirs?

[marc gogarty]

yes i was too emotional / hypocritical / i am a social failure . thats why i cruise singlehandedly (not like George Michael!)
the best thing about all of this is that nobody said the boat would snap in half (yet)
there are some excellent traditional boat builders where i am moored on the thames
perhaps the idea will seem less radical to river men than wet bummed dinghy sailors
i will post some pictures of the completed experimental craft with a nice bird sitting in it

ps the mast is going to be stepped on the 'keel'
pps the sitka gaff rig is actually lighter than the original aluminium - honest!
ppps a fine season of sailing to you all

[Candyfloss]

Quote:

"perhaps the idea will seem less radical to river men than wet bummed dinghy sailors"

Really, Marc. I just reread the thread, and no-one called you rude names.

You can't shoot the messenger just 'cause you don't like the message.

[marc gogarty]

absolutely.....
at school we used to call sailors and scullers 'wet bums' or 'wet bobs'
no insult intended.
ps considering the vast amount of 'donts' from experienced contributors i have forestalled my plans.
i have bid on a 'knackered' enterprise with no transom - to take apart and consider the options.

i suppose forum-wise i came out of the channel into a squall, broached and blamed the weather helm

[James McMullen]

Welcome aboard, sailor!