Wooden boat repairs

[Jameshow]

I wish someone would start making this sort of small inboard engines again. Preferably modernised with overhead valves to allow for a better shaped combustion chamber to cut down fuel consumption even further.
Bröderna Wickströms Motorfabrik was disolved in 1980 and most of the casting patterns are lost. However it wouldn't be too hard to reverse engineer a motor and make new patterns.... if there only was more time and more money.....

In our time with rising fuel prices coinciding with the need to radically cut fuel consumption this would be a feasible future for motor boating. A 2-5 hp inboard on a straight shaft in a sleek easily driven displacement hull chugging away at 4 or maybe 5 knots.

Send it to China!!

What about a hatz or kabota single cylinder diesel.

 

[Inspector]

I think you will find battery powered motors showing up first. Adaptations of ride on lawnmower motors for example. Now whether they will pollute less or not, especially when the source of charging power has to be considered, I can’t say. Definitely quieter though.

How about a modern steam engine?

Pete

 

[heimlaga]

Send it to China!!

What about a hatz or kabota single cylinder diesel.

Neither Hatz nor kubota makes motors small enough for this purpose. The smalles Kubotas I have managed to find are around 10 hp which is 2-5 times too large.
Another problem is that a small inboard in an easily driven displacement hull must have a torque curve suitable for the purpose. For maximum energy efficiency it has to swing a comparatively large two blade screw (The 2 hp Wickström uses either a 11 1/2 or a 12 inch diametre screw). For this you need a motor with plenty of torque under load at any RPMs between idle and full throttle. Which implies a slow running motor with long piston stroke. The Wickström should for instance run at something like 1000-1200 rpm at full throttle.
Modern general purpose motors tend to be high RPM low torque motors with short stroke.

 

[Jameshow]

Neither Hatz nor kubota makes motors small enough for this purpose. The smalles Kubotas I have managed to find are around 10 hp which is 2-5 times too large.
Another problem is that a small inboard in an easily driven displacement hull must have a torque curve suitable for the purpose. For maximum energy efficiency it has to swing a comparatively large two blade screw (The 2 hp Wickström uses either a 11 1/2 or a 12 inch diametre screw). For this you need a motor with plenty of torque under load at any RPMs between idle and full throttle. Which implies a slow running motor with long piston stroke. The Wickström should for instance run at something like 1000-1200 rpm at full throttle.
Modern general purpose motors tend to be high RPM low torque motors with short stroke.

I'll take my PAW diesel down to the photocopier and enlarge it for you!

 

[worn thumbs]

A cement mixer engine might fit the bill,but it would need a supply of cooling air and be a bit noisy.You would also have to sort out a dry exhaust and both insulation and rain repelling solutions.

 

[MF1000]

A good old single cylinder Lister

 

[glenfield2]

Electric maybe? Small, non-polluting and blissfully silent. A wide variety here:
https://electricboatassociation.org/

 

[MF1000]

I may be a traditionalist but given the age of the boat a single cylinder low revving Lister or Petter engine feels with that ‘put put’ sound is totally in keeping with the boat and to me almost hypnotic in rhythm when on the water.

 

[Qwercus]

Send it to China!!

What about a hatz or kabota single cylinder diesel.

Never tried it but I always thought an LE Velocette motorbike engine would make a great inboard boat engine. Water cooled, 200cc, side valve, boxer twin with gearbox and shaft drive. Fuel is petrol of course.

 

[heimlaga]

It is starting to look like a boat from the inside. I am working on the engine cover and the exhaust plumbing.

We sawed some boat planking stock for future projects.

 

[heimlaga]

Harvesting a new breasthook for another boat. I had left a high stump when I felled the tree in winter and when the ground had thawed I could uproot it. The road was closed so I had to uproot the stump entirely by hand as I couldn't get there with the tractor.

 

[TRITON]

How about a modern steam engine?

I've always wanted a small steam launch. Something suitable to tour the UK canals on.

 

[heimlaga]

The job is finished. Only the stern tube and propeller is still missing.

 

[heimlaga]

Besides this I have also scrapoed the inside of a 16 for planing skiff clean from paint and oiled it. You cannot paint the inside of a spruce boat in our climate. The wood must be able to breathe or it will rot very fast.

 

[whereistheceilidh]

The job is finished. Only the stern tube and propeller is still missing.

Lovely job! With a heel like that I hope you have somewhere flat/soft to park it.

 

[heimlaga]

Lovely job! With a heel like that I hope you have somewhere flat/soft to park it.

We don't have much in the way of tides in Finland. Theoretically there is but it is a matter of maybe a centimetre while the water level may rise and fall within a range of roughly one and a half metre depending on winds and rainfall and air pressure.
Anyway we don't normally keep boats on drying out moorings. Either they are hauled out or kept afloat. Hence that heel isn't too much of a problem.

Boulders on the seafloor is much more of a problem and they sooner or later tear the blades of every unprotected propeller. Around here we have so many reefs that it is only during the last 20 years that the blank areas formerly found on every sea chart have been filled in little by little. Before accurate GPS there was no way any government could afford to measure the position of every reef. You have to go 10-20 nautical miles out to sea before you find water that isn't full of reefs and islands all made up from boulders stacked one upon another. Locals tend to know their home waters of cause but humans tend to make misstakes and the reefs change shape as boulders are pushed around by ice floes all while the land and sea floor rises from the sea at the rate of 8mm a year. This is the reason for the complicated and in the eyes of foreigners weird ironwork beneath the propeller.

When waves from the open sea enters into this shallow layrinth they become very short and steep and wave systems ofter crisscross on top of one another. This is the reason for the extreme flare and rake in the ends of locally designed motor boats. It is also the reason for the comparatively heavy framing in the ends.

 

[Jameshow]

We don't have much in the way of tides in Finland. Theoretically there is but it is a matter of maybe a centimetre while the water level may rise and fall within a range of roughly one and a half metre depending on winds and rainfall and air pressure.
Anyway we don't normally keep boats on drying out moorings. Either they are hauled out or kept afloat. Hence that heel isn't too much of a problem.

Boulders on the seafloor is much more of a problem and they sooner or later tear the blades of every unprotected propeller. Around here we have so many reefs that it is only during the last 20 years that the blank areas formerly found on every sea chart have been filled in little by little. Before accurate GPS there was no way any government could afford to measure the position of every reef. You have to go 10-20 nautical miles out to sea before you find water that isn't full of reefs and islands all made up from boulders stacked one upon another. Locals tend to know their home waters of cause but humans tend to make misstakes and the reefs change shape as boulders are pushed around by ice floes all while the land and sea floor rises from the sea at the rate of 8mm a year. This is the reason for the complicated and in the eyes of foreigners weird ironwork beneath the propeller.

When waves from the open sea enters into this shallow layrinth they become very short and steep and wave systems ofter crisscross on top of one another. This is the reason for the extreme flare and rake in the ends of locally designed motor boats. It is also the reason for the comparatively heavy framing in the ends.

I thought the sea level was rising?!

 

[TRITON]

I wish someone would start making this sort of small inboard engines

https://www.ebay.co.uk/itm/295768381012?epid=21057415007&hash=item44dd2b5654:g:AosAAOSwtDFjX5XY

 

[Adam W.]

I thought the sea level was rising?!

Could be isostatic rebound which is causing it.

 

[heimlaga]

Could be isostatic rebound which is causing it.

It is. The ice age weighed down the earth's crust and now it is floating back up all while the German coast and to a lesser extent Denmark are sinking as the bubble of surplus material they are sitting on is drained.
In the last decade the land has been rising at a slower than normal rate maybe some 5 mm a year because the sea level is rising too.