Tunnelstuff in Norway

[Andy Greene]

Here`s another build that is almost ready for test. Hull is AN-790 (design by Andreas Nodland)

Plan was to try the Nova Rossi .46 on this one, and I think it might be possible to check out the .67 as well. Gonna need some extra weight in front cause the .67 is a lot more heavy than the .46

Planning for another bigger tunnel later that will have the .67

The AN-790 has been previously used as electric, running 6S and motor with a maximum power at 5kw. (continius power at 2,35kw)

Works pretty good even though the weight is quite high with electric setup.

Who makes those pushrod connectors on the steering rods Joern ? in the 3rd pic.

 

[Joern Markset]

is your nova rossi ob water cooled , ? if air cooled , how do you prevent over heating....bob

It is freakin cold in Norway, it is almost impossible to get the correct temperature. That is why I took of the aircoolinghead and replaced it with watercooling jacket (without watercooling). Less heat disipate, but still can`t get it hot enough.

Have you tried a thin gasket/spacer between pto and low unit to slow down the heat transfer/dissipation?

Heat is certainly your friend! (Till a point of course)

No, maybe a thin teflongasket would help keep some heat Good tip

 

[Joern Markset]

You could pre-heat the water going to the head with a coil around the exhaust header. Another way is to wrap the exhaust pipe to keep heat in the pipe and returning pulses to the motor. Outboard pipes cool very quickly. (wind chill). I used to live in Minnesota so I understand cold weather, like just after the ice goes out and you've been waiting months to run a boat.

Mic

The thing is that we run a short triangle circuit, that means even the pipe does not get hot.

We will make some new very small coolingjackets and try out

Wrap the pipe might be worth trying, thanks

 

[Joern Markset]

Here`s another build that is almost ready for test. Hull is AN-790 (design by Andreas Nodland)

Plan was to try the Nova Rossi .46 on this one, and I think it might be possible to check out the .67 as well. Gonna need some extra weight in front cause the .67 is a lot more heavy than the .46

Planning for another bigger tunnel later that will have the .67

The AN-790 has been previously used as electric, running 6S and motor with a maximum power at 5kw. (continius power at 2,35kw)

Works pretty good even though the weight is quite high with electric setup.

Who makes those pushrod connectors on the steering rods Joern ? in the 3rd pic.

It is something "homemade" by the boat designer. We do a lot of testing together, and since he is running a cnc workshop he make the stuff that can't be bought, or if we get an idea and want to realize it

They are inspired from the wire tensioners we use, made by Secraft

 

[LarryConrad]

You could pre-heat the water going to the head with a coil around the exhaust header. Another way is to wrap the exhaust pipe to keep heat in the pipe and returning pulses to the motor. Outboard pipes cool very quickly. (wind chill). I used to live in Minnesota so I understand cold weather, like just after the ice goes out and you've been waiting months to run a boat.

Mic

Some of us still live up here in Minnesota,Mic

With the varying air and water temperatures that occur in this area, I've had poor results with air cooled setups. In the middle of Summer when water surface temps can be in the mid to high 80's F and air temps are normally in the 80's and 90's F, they run too hot and I've had issues trying to get consistent runs. The rest of our open water season when the air and water can be considerably cooler my limited amount of testing with air cooling has been less than desirable as the engines I've tested wouldn't get hot enough to "turn on".

 

[Joern Markset]

You could pre-heat the water going to the head with a coil around the exhaust header. Another way is to wrap the exhaust pipe to keep heat in the pipe and returning pulses to the motor. Outboard pipes cool very quickly. (wind chill). I used to live in Minnesota so I understand cold weather, like just after the ice goes out and you've been waiting months to run a boat.

Mic

Some of us still live up here in Minnesota,Mic

With the varying air and water temperatures that occur in this area, I've had poor results with air cooled setups. In the middle of Summer when water surface temps can be in the mid to high 80's F and air temps are normally in the 80's and 90's F, they run too hot and I've had issues trying to get consistent runs. The rest of our open water season when the air and water can be considerably cooler my limited amount of testing with air cooling has been less than desirable as the engines I've tested wouldn't get hot enough to "turn on".

Sounds exactly like Norway

 

[LarryConrad]

There are a lot of people of Scandinavian decent in the upper Midwest. I did have one aircooled outboard that ran fairly consistent. It was a K&B SS 21. You have some great looking tunnels Joern.

 

[Kris Flynn]

I admit I have not searched for any videos, but have you got a link to a few of your style of F1 racing Joern?

I feel we need to 'spice' up the racing of outboards here in Australia...seems to have gone 'stale' again. Triangle or even M courses would be an excellent way to get the excitement back again. I know I had ALOT of fun racing on the Tri-Oval in the USA a few years ago!

 

[Joern Markset]

Kris, I'm sorry we have not got much videos yet.

This class (called OTA) was very popular on the 90's and to the middle of 2000. Since 2004/5 it has been laying with its back broken so to say.

Couple of years ago I tried to gather some guys and start racing electric with old tunnels previously raced in OTA.

That was the new start for the tunnels in Norway, and this year we relaunched the OTA class again. Unfortunately we are very few racers at the moment, but I have reason to believe it will grow bigger.

We have allready been talking about an M course. In electric we tried different layouts with and without a shicane buoy. Common for all tracks was the need for hard turns, just like the 1:1 scale. As soon as we get some videos I will post links.

Gonna use this thread to post some of the stuff we do here in Norway if anyone is interested in what we do.

 

[Kris Flynn]

Keep me/us in the loop!

Very interested to see what you guys/girls are getting upto!

 

[Joern Markset]

Went out today to do further testing of the OS VS PTO from Rody. I got a new piston/liner from the VS B01 that I wanted to try out. Problem was that even my modified headbutton wouldn`t go deep enough to give me the squish I wanted. I decided to give it a try though. It runs ok for sure, but with lack of torque when could not get harder squish than 0,45 mm.

So I swaped again with the stock P/L. The stock piston has a curved top that does not completely match the shape of the headbutton, so when I measure 0,30 mm close to the linerwall I get this nice clean ring on the piston top. Hahaha!

Rody suggested a new pipe that I could try to see if it gave a little more bottom torque, and it did, was very satisfied with it. However I still need extension.

All in all I am very satisfied with the engine from Rody, no doubt.

Furthermore I need to do a rebalance of the tunnel as I had to add too much weight in the front. Should be no need to add extra weight if you can play with the needed stuff you actually have to put in the boat like servos, batteries etc.

 

[Joern Markset]

BTW, which is the best flexcable money can buy for the K&B .21 lower?
I really can`t understand why I start break cables as dry spaghetti now when I run glow... I run electric as well on the same lowers with at least twice the power of a .21 and with heavier props and the cables last much longer.

As for now I have Strongarm, Lawless, Hyperformance and K&B cables. It seams like the K&B cables are the best.
Hyperformance have so far had the shortest life in my lowers...

@Kris, I know you make some cables, do you make the "hot stuff"?

 

[Kris Flynn]

Happy to send you some Cables...no unhappy customers (that I know of haha)

It is very important in a K&B lower to run a brass tube (Jerry Dunlap did a great article on this) and also a friend (David Moyle) and I came to the conclusion that in a K&B lower it is very important to keep the square drive into the prop shaft as short as possible. So on my shaft there is a very short square part compared to others, especially a K&B. it is also very important to ensure you cable does not bind up...if you push the prop/stub shaft in and it pushes back out then your cable is probably too long and will cause failures.

What do you oil/grease your shafts with? I really like outboard gear oil...

I have been talking to a few guys from Portugal recently, they have similar requirements to you. They also seem to race in very rough water compared to others which adds another element.

I assume the hull you run is 660mm long? (26") pretty short to what I am used to these days. I assume your top speeds are 75-80km/h, but aiming to turn at full speed and not lose much speed in those sharp corners on your triangular course? maybe only 10-15km/h max? How does the Villain S1 (VS1) or a Vision compare in your racing (if any race over there)?

 

[Joern Markset]

@Kris, I`m totally following you, cable breaks almost without exception right in front of the propshaft where it starts to bend pretty hard.
I`ve allways made up brassliners, but now when you mentioned it I became in doubt if I may have forgot to do it on this lower. Have to check it out...

I`ve tried to shorten the cables a little bit as well to secure good play, but it did not make any difference.
I use castor oil or Omega 690 as lubrication. The Omega gear oil is amazing, however when it is cold the viscosity is too thick.

I`ll shoot you a pm and ask for 10 cables as a start.

You are correct about the hull length, the AN-660 is 660 mm long. Common length for 3,5 is around 700 mm pluss minus

And you are corrrect about the speed as well, in a race probably below 70 km/t due to traffic and rough water.

Couple of years ago I bought two VS-1 tunnels that I modified. I cut it in two halves thru the centerline and widened it by 20 mm. Then I modified the front end of the sponsons, they were widened as well to prevent the boat from falling thru the water when you put it down hard in front of a turn. Guess you know exactly what I mean.

It was driven with active tilt feature, and that worked out much better than I was hoping for.
After some testing I found the best endpoints for in and out, and I used a pushbutton on the radio to opperate the tilt.

But at the end this boat was so soaked in epoxy and extra material that it became too heavy, so it was thrown on the shelf and I believe they were given to a fellow boater at one point.

I know there was a Villain S1 racing in the OTA class back in the mid 2000`s, as far as I remember it ran pretty good.

 

[Joern Markset]

Throwing out some pics from an AN-680 being built.
This is how most of the Norwegian tunnels are constructed.

 

[Kris Flynn]

Once again...stunning builds there. Takes alot of care and craftmanship to get them that clean at the end.

Nice and simple layout of the formers.

The outer edge having a "negative" angle id also different and looks nice also. Does the designer have a practicle reason for that? Or just what they wanted?

Did you build them? Or just the final fitout?

Thanks for sharing

 

[Joern Markset]

Once again...stunning builds there. Takes alot of care and craftmanship to get them that clean at the end.

Nice and simple layout of the formers.

The outer edge having a "negative" angle id also different and looks nice also. Does the designer have a practicle reason for that? Or just what they wanted?

Did you build them? Or just the final fitout?

Thanks for sharing

The AN-680 is a prototype based on the previous AN-660 just to check out some different angles and measurements on the ride pads.

The negativ curved deck is just something he wanted for the look, it does not do anything to or from.

All AN tunnels are built by the designer himself. When I get them I have to do all setup + coating etc etc.

It is a nice team work as I supply him with different motors, lowers etc for testing. I don`t have the needed time do all testing my self.

 

[anders-e]

Nice looking boat Joern

 

[Joern Markset]

The AN-790 is now ready to be taken out for a testrun. This will be the maiden start of the NR .46 as well, so it has to be broken in and the pipe length adjusted. Probably gonna need to adjust some balance too ;-)

 

[Grimracer]

Would like to see Video..

Grim