Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Steam => Topic started by: KBIO on April 03, 2021, 09:45:31 am

Title: The Yar (KBIO)
Post by: KBIO on April 03, 2021, 09:45:31 am

First pic shows that there is a good « entente cordiale » between fishermen and steamers in Brittany ! A pack of beer facilitating the relations ! ;-))
The Car is a river on the Brittany coast.
Originally , this launch is a torpedo launcher but I preferred to  make a fishing/hunting civil version as I like the shape of the hull and that I can work on the details .
Thanks to a member of my Forum, I had the frame laser cut. This is the first time that I use this process and I must say that it saves a lot of time cutting & filling.
As long as I don’t pay , …. I buy ! ;)
The boat size is around 90 cm and she weights 5/6 kg.
The engine is 3 cc JMC that I had to review integrally as the previous owner thought that he has some mechanics talents ! It comes with a Stephenson reverse .
Notice that the engine is inclined inside the boat. Due to the shape of the keel and the horizontal plan , I could not place the engine right in front of the stern tube.
I did not want to position it above the tube ( too high ) and I couldn’t set it horizontally. So, with a couple of gears, ratio : 1/1.25 - I have my engine centered and operating .
The boiler is a  500 cc Bourdillat  . The burner (as always ) is a 130 g/H Bobino ) .
55 mm Raboesh Propeller. Autonomy : 45 min.


https://youtu.be/ (https://youtu.be/)


https://youtu.be/ZqqpCXaCdbw (https://youtu.be/ZqqpCXaCdbw)
https://youtu.be/tLGa9kPzlnw (https://youtu.be/tLGa9kPzlnw)


The video shows that the propeller is well sized for the hull’s shape & weight , even if she is full blast for the demo (too fast), I have a problem with this set up as I reach 3 bars within 5 min and that when the engine runs , the boiler pressure still buids up.
Either I change the burner , either I install a gaz pressure reducer ! Most probably the easiest and safest . More work :-=) . Changing the gear ratio will not improve anything .  But for sure , I have to do something.
On top, of it , I realize that the pop off valve is stucked ! This boat never sailed (10 yearsold ) and has been tested only once without poping the safety valve !
What a life !
Regards.
Title: Re: The Yar (KBIO)
Post by: KBIO on April 03, 2021, 09:57:42 am
Another ...
Title: Re: The Yar (KBIO)
Post by: KBIO on April 03, 2021, 10:18:24 am
Again ??

Title: Re: The Yar (KBIO)
Post by: KBIO on April 03, 2021, 11:29:07 am
Just a bit more and that's it ! %)
Title: Re: The Yar (KBIO)
Post by: derekwarner on April 03, 2021, 01:28:29 pm
I have seen this before KBIO with the engine on the slant  {-) .......she is of graceful lines :kiss: , but still tender in stabity ..... Derek
Title: Re: The Yar (KBIO)
Post by: KBIO on April 03, 2021, 05:30:07 pm
Good evening !
You are right Derek , I have a tendency to enlarge my rudders , so that swings ! %)
Today I gardened a bit (my wife order ! >>:-( <*< ) and I changed the blow torch with a Clevedon 29 mm burner. I'll test tomorrow !
Thanks for watching !
Best regards !