the thrust from an inboard on a 26 foot yacht

dylanwinter said:
I am hoping... still hoping to keep it simple by having access to the screws above the level of the cockpit but until Roger measures the distance for me I am still unsure

taking on Cape Wrath with an outboard on a bracket and all those nasty bars with their short chops is not something I fancy
I have just edited a film of me messing with Wells bar

it was bloody horrible with an outboard on the back of the slug

I then turned around and did the same thing using the slug inboard

it was that experieent - plus my experiences with eboats and sonatas that has set me on the well course

D
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Fair point on the bars.

I had an unfortunate experience some years ago with a seagull on a bracket on the transom of a C&C 24.
It was a regular shaft seagull. All 1 hp. The bracket was set low.
I was taking a couple of friends and my future Mother in Law out for an afternoon sail on English Bay. It was a flood tide and a flood wind. (strong onshore breeze).
I had just motored out under Burard bridge while still in the channel where sailing is not allowed.
I was overtaken by a large inconsiderate MOBO on the plane in the slow zone.
The MOBO's wake ducked my seagull underwater and killed it.
A few yards of a lee shore.
A tug was coming in the channel with a cement barge.
Running about like a blue a!#$%d fly. Main up heading towards tug then tacking back out of its way while trying to get the jib up.

Unfortunately at some point during this I allegedly swore at my Mother In Law or merely explained I knew there was a tug coming the other way. Our stories conflicted.

I have been constantly reminded about this incident for the last 20 years or so.

She has never come sailing with me since
 
I have a storeage bracket for my Tohatsu 3.5 made up from 25mm ply. It's not really thick enough. I'd think very carefully about doing a transom in it and decide on something bigger. My Rubbydub has a transom made from 35mm timber and a cast plate screwed to that.
 
Topcat47 said:
I have a storeage bracket for my Tohatsu 3.5 made up from 25mm ply. It's not really thick enough. I'd think very carefully about doing a transom in it and decide on something bigger. My Rubbydub has a transom made from 35mm timber and a cast plate screwed to that.
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the actual bracket will be either a lump of hardwood or several layers of ply stuck together with epoxy

the 25mm ply is really for the well box and structural bits that will tie the structure back to the rest of the boat

some-one suggested that I should just build a cupboard where the engine was - then I can use the structure to take the forces back to the old inboard bearers - this seems like a reasonably sensible solution

I can put all my heavy junk there and bring the Centaur back onto her lines

your thoughts?

D
 
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The well on our TS originally had a simple U shaped laminated plywood support for mounting the OB. It is just high enough above the cockpit sole to allow the OB clamp bolts to be tightened. The support spreads the load and thrust of the outboard onto the cockpit sole. I may have some pictures which I can upload. However I have added a stainless L shaped gusseted angle which reinforces the original mount with the upright in front of the wood and through bolted on the horizontal surface to the Cockpit sole This provides a means of transmitting all the loads from the OB to the boat via the Cockpit sole.

With our configuration we only need to use a standard shaft engine with the prop just below the hull. We have never had the prop come out of the water even in extreme short wind against tide chop that we experience around Anglesey. However a long shaft is preferred as we have experienced picking up rafts of sea weed on the prop usually at the worst possible time.
 
TSB240 said:
The well on our TS originally had a simple U shaped laminated plywood support for mounting the OB. It is just high enough above the cockpit sole to allow the OB clamp bolts to be tightened. The support spreads the load and thrust of the outboard onto the cockpit sole. I may have some pictures which I can upload. However I have added a stainless L shaped gusseted angle which reinforces the original mount with the upright in front of the wood and through bolted on the horizontal surface to the Cockpit sole This provides a means of transmitting all the loads from the OB to the boat via the Cockpit sole.

With our configuration we only need to use a standard shaft engine with the prop just below the hull. We have never had the prop come out of the water even in extreme short wind against tide chop that we experience around Anglesey. However a long shaft is preferred as we have experienced picking up rafts of sea weed on the prop usually at the worst possible time.
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all the images you send me or post will be carefully scrutinised

love to see some
 
ghostlymoron said:
That looks a nice engine!
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That is because it is a Yanmar 1GM which would meet all of Dylan's criteria for simplicity, reliability and low cost, but unfortunately is not powerful enough for a Centaur, although it would, with a 3:1 box and a 15" prop be better than the proposed outboard.
 
Tranona said:
That is because it is a Yanmar 1GM which would meet all of Dylan's criteria for simplicity, reliability and low cost, but unfortunately is not powerful enough for a Centaur
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Cobblers. Not everyone wants a motorsailer, and a 1GM10 is a perfectly adequate auxiliary for a yacht the size and weight of a Centaur.
 
A Macwester 26 is a big roomy boat and also the slowest VMG to windward in all of sailing's history. In fact I don't think it actually does go to windward! A Mac27 or 28 is a very different beast. One sold a few years ago with a brand new Beta for £5k. Bargain boats with new engines are out there. As for 9.9hp not being enough - tosh I say - we had a Heavenly Twins 27 cat weighing in at 3.5tonnes happily in and out over Deben bar against the tide, all with a Mercury 9.9hp with a high thrust prop.

Storing and sourcing the petrol was a right PITA on cruises though.
 
Have you discussed this project with your insurance company yet? Will they really be happy to cover you when rounding the top of Scotland with the tides etc up there?
 
rhumlady said:
Have you discussed this project with your insurance company yet? Will they really be happy to cover you when rounding the top of Scotland with the tides etc up there?
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No engine in a Centaur will be sufficient to counter the tides. You go with the flow instead.

Insurance policies usually just lump all of UK waters together anyway.
 
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