rigger pulling to the right ?

[speakerboy]

Well. its been a while , and i did some more testing . , i changed the angle on the CMDI turnfin and it turned much better , no more lifting the sponson . it also pulled less than before .. but it is still pulling .. on flat water the Virginia craftman fin is still the best , it pulls not so much and is real stable in the turns ,but .. a tat slower .

next setup will be ..

this rigger with the CMD turnfin . and same setup . i will work on the pulling and will try other tricks like shims and toe in on this boat ..

i will built the same riger with the same setup with the virginia craftman fin and use that for heat race , but now with a 2716/2 blade prop , handling is amazing , speed is pretty good for a gas rigger 74 mph and that should do it normally , good thing is , with this prop there is almost No pulling and i can steer oval laps easy !

last sunday the water was kinda rough but wanted to test the boat in heat race setup ... it survived ,, but barely .. check out some awesome hydro shots ...

Jeroen

 

[eric wong]

My rigger runs straight with a 2 blade voodoo 7521 prop, I didn't do any offset or shimm angle to the rigger, the turn fin was sharpened that came from the rigger builder.

 

[impba3548]

Jeron,

I am following what you are doing, and its very interesting, I am wondering what prop youre using and what your elevation is where you run? We had a thaw this week, so tomorrow or one day this week I plan to go try out the orange boat again. I made up a small fin for it that is adjustable depth, new cowl that is more aerodynamic and different sponsons that have smaller frontal area - should be less drag, we will see..........

mike sr

 

[speakerboy]

he Mike ... thanx for your interest , playing with riggers and fins and sorts is big fun . here the water is freezing up and i cant get the motor to reach a normal temperture , that said i am loosing rpm and top speed , so i will wait until the sun is warmoing up the lakes again . mean while i will built a new hobby room and have some plans with the rigger .. i will use the twister for Saw and will contignue with a new AB fin . (i have to order though .. ) besie the Saw rigger i will also built a 4 ore 5 inch wide heat racer with a good zenoah inside .. that boat will run with the verginia craftman fin. i hope to reach speed somewhere at 65 mph with that boat , that would do it in heat race ..

i am planning on working with different ppes on the Saw version and will start working with shims and some extra set of booms and sponsons to test with toe in and all the tricks i have rea here at this topic .. right now i am at 85 mph , and i am gambling on 87 till 90 mph .. if i got that to happen with a straight running saw boat , i am a real happy camper !

enjoy the cold ! till next spring ...

Jeroen

 

[impba3548]

he Mike ... thanx for your interest , playing with riggers and fins and sorts is big fun . here the water is freezing up and i cant get the motor to reach a normal temperture , that said i am loosing rpm and top speed , so i will wait until the sun is warmoing up the lakes again . mean while i will built a new hobby room and have some plans with the rigger .. i will use the twister for Saw and will contignue with a new AB fin . (i have to order though .. ) besie the Saw rigger i will also built a 4 ore 5 inch wide heat racer with a good zenoah inside .. that boat will run with the verginia craftman fin. i hope to reach speed somewhere at 65 mph with that boat , that would do it in heat race ..
i am planning on working with different ppes on the Saw version and will start working with shims and some extra set of booms and sponsons to test with toe in and all the tricks i have rea here at this topic .. right now i am at 85 mph , and i am gambling on 87 till 90 mph .. if i got that to happen with a straight running saw boat , i am a real happy camper !

enjoy the cold ! till next spring ...

Jeroen

I have had one run of 89, several runs a couple days later of 87.2 to 88 flat, that day wasnt as cold and the barometer was lower. I have my best runs when its very cold out and the needle is so rich the plug is black, if I lean it any it slows down. It pulls horrible at that speed, the smaller fin will help that I believe. I too am looking for 90 or better, just a personal goal for the year....... I use the camp fuel too maybe thats why it runs better in the cold?? I would like 90 on a regular basis but that would take 92 to 94 on a special day.

Our lake is about 850 yards long and 300 yards wide 40 plus acres so its ideal for straightaway rigger use.

prop walk is a concern but that turn fin dragging in the water at 90 will cause a big problem with the right pulling thats for sure ha!! I am also thinking about a small fin on each sponson to see if that helps as I can slow down for the turns.

I have had 3 different styles of front sponsons on this boat, and they all seem to run almost the same. I have taken the fin off and the pull goes away but it will not turn at all.......... I have a new cowl that covers the carb better, lots of new things to try, just need soft water on a regular basis ha!!

good luck with yours and may it be a mild winter ha!!

'A fast rigger trips my trigger"

mike sr

 

[ken liu]

My rigger runs 83.5 mph with a Malachi 2170 prop but the speed seems a bit slow to me since we have a big size pond here, I'm going to mount a shorter pipe on it, if the engine can unload this prop with this shorter pipe, it should pick up 3-4 miles cause I had aleady tested the pipe on my cat and it works.

 

[Scott Schneider]

Jeroen,

Been reading on this for months waiting to see a solution

Just an observation and helping suggestion for whats it worth.

Personally NEVER have liked or gotten the rigidity required using sandwiched turnfin & bracket off the inside of sponson. IMO just not robust enough and prone to flutter like a flag in a stiff breeze.

Basically stating that the turn fin running threw the water acts like a flag does in the wind. Even tho the fin is metal and does not flap back and forth like a flag does, the fact it is subjected too such high pressure running threw the water it by design would shutter back and forth if it could. And to some degree it actually does.

Have you tried a MUCH more robust fin mounting that has a support strut anchoring the rearmost section of fin/bracket back to the side of tub ?

** Something along these styles ?

 

[John Finch]

Jeroen,
Been reading on this for months waiting to see a solution

Just an observation and helping suggestion for whats it worth.

Personally NEVER have liked or gotten the rigidity required using sandwiched turnfin & bracket off the inside of sponson. IMO just not robust enough and prone to flutter like a flag in a stiff breeze.

Basically stating that the turn fin running threw the water acts like a flag does in the wind. Even tho the fin is metal and does not flap back and forth like a flag does, the fact it is subjected too such high pressure running threw the water it by design would shutter back and forth if it could. And to some degree it actually does.

Have you tried a MUCH more robust fin mounting that has a support strut anchoring the rearmost section of fin/bracket back to the side of tub ?

** Something along these styles ?

Scott,

I really like the flex collet mounted to the hull so you can adjust the length of the brace. That is awesome! You talk about flex...........My gas sport hydro fin flexes to the point that it eventually stays misaligned. The fin itself bends. I just leave it bent and it works fine. It kind of finds a set. A thicker fin is what I need on that one. I use fin braces too, on my outriggers, but mount mine to the back of the sponson rather than on the tub. I would think the tub mount would also help sponson stability. Neat setup you have on the angled bracket too!

 

[Scott Schneider]

John,

Both styles allow moving the fin forward and rearward to find the ideal Cg to fin position.

Both styles allow inward or outward toe in/toe out adjustment.

*Yes, a robust support strut also really stiffens up the whole sponson assembly

You CAN pick up the hull by the fin bracket and actual fin itself without flex or alignment changes

 

[Marty Davis]

Jeroen,
Been reading on this for months waiting to see a solution

Just an observation and helping suggestion for whats it worth.

Personally NEVER have liked or gotten the rigidity required using sandwiched turnfin & bracket off the inside of sponson. IMO just not robust enough and prone to flutter like a flag in a stiff breeze.

Basically stating that the turn fin running threw the water acts like a flag does in the wind. Even tho the fin is metal and does not flap back and forth like a flag does, the fact it is subjected too such high pressure running threw the water it by design would shutter back and forth if it could. And to some degree it actually does.

Have you tried a MUCH more robust fin mounting that has a support strut anchoring the rearmost section of fin/bracket back to the side of tub ?

** Something along these styles ?

Scott:

I had the same problem for years and years with the turn fin mounting system. I have FINALLY found a great answer and it works perfectly on all sized boats.

I bought a piece of 1/8" thick carbon sheet from Aerospace Composites and I make a doubler out of that and make the mounting holes exactly like what the turn fin has. I then use 2 4/40 SHCap Screws throught both pieces and it is totally rigid and will not bend at all. Best of all the carbon has memory that keeps it completely straight. That makes the aluminum fin stay perfectly straight. I suspose that on a really big boat like a twin, etc. you could use 3/16" carbon to make it REALLY STIFF.

Be sure that you put the carbon doubler on the outside of the fin so that the water doesn't find the doubler.

 

[Terry Keeley]

Jeroen,
Been reading on this for months waiting to see a solution

Just an observation and helping suggestion for whats it worth.

Personally NEVER have liked or gotten the rigidity required using sandwiched turnfin & bracket off the inside of sponson. IMO just not robust enough and prone to flutter like a flag in a stiff breeze.

Basically stating that the turn fin running threw the water acts like a flag does in the wind. Even tho the fin is metal and does not flap back and forth like a flag does, the fact it is subjected too such high pressure running threw the water it by design would shutter back and forth if it could. And to some degree it actually does.

Have you tried a MUCH more robust fin mounting that has a support strut anchoring the rearmost section of fin/bracket back to the side of tub ?

** Something along these styles ?

Scott:

I had the same problem for years and years with the turn fin mounting system. I have FINALLY found a great answer and it works perfectly on all sized boats.

I bought a piece of 1/8" thick carbon sheet from Aerospace Composites and I make a doubler out of that and make the mounting holes exactly like what the turn fin has. I then use 2 4/40 SHCap Screws throught both pieces and it is totally rigid and will not bend at all. Best of all the carbon has memory that keeps it completely straight. That makes the aluminum fin stay perfectly straight. I suspose that on a really big boat like a twin, etc. you could use 3/16" carbon to make it REALLY STIFF.

Be sure that you put the carbon doubler on the outside of the fin so that the water doesn't find the doubler.

One nice thing about carbon (well one of the nice things ) is that it's either straight-or it's broke. :lol:

 

[Terry Keeley]

Here's a cool little calculator to figure centrifugal ("centripetal" really) force:

http://www.calctool.org/CALC/phys/newtonian/centrifugal

I figured a 10lb. boat going through the turn at 75 mph had over 100lb. hanging off the fin!

 

[Marty Davis]

Jeroen,
Been reading on this for months waiting to see a solution

Just an observation and helping suggestion for whats it worth.

Personally NEVER have liked or gotten the rigidity required using sandwiched turnfin & bracket off the inside of sponson. IMO just not robust enough and prone to flutter like a flag in a stiff breeze.

Basically stating that the turn fin running threw the water acts like a flag does in the wind. Even tho the fin is metal and does not flap back and forth like a flag does, the fact it is subjected too such high pressure running threw the water it by design would shutter back and forth if it could. And to some degree it actually does.

Have you tried a MUCH more robust fin mounting that has a support strut anchoring the rearmost section of fin/bracket back to the side of tub ?

** Something along these styles ?

Scott:

I had the same problem for years and years with the turn fin mounting system. I have FINALLY found a great answer and it works perfectly on all sized boats.

I bought a piece of 1/8" thick carbon sheet from Aerospace Composites and I make a doubler out of that and make the mounting holes exactly like what the turn fin has. I then use 2 4/40 SHCap Screws throught both pieces and it is totally rigid and will not bend at all. Best of all the carbon has memory that keeps it completely straight. That makes the aluminum fin stay perfectly straight. I suspose that on a really big boat like a twin, etc. you could use 3/16" carbon to make it REALLY STIFF.

Be sure that you put the carbon doubler on the outside of the fin so that the water doesn't find the doubler.

One nice thing about carbon (well one of the nice things ) is that it's either straight-or it's broke. :lol:

EXACTLY...

 

[Scott Schneider]

Jeroen,
Been reading on this for months waiting to see a solution

Just an observation and helping suggestion for whats it worth.

Personally NEVER have liked or gotten the rigidity required using sandwiched turnfin & bracket off the inside of sponson. IMO just not robust enough and prone to flutter like a flag in a stiff breeze.

Basically stating that the turn fin running threw the water acts like a flag does in the wind. Even tho the fin is metal and does not flap back and forth like a flag does, the fact it is subjected too such high pressure running threw the water it by design would shutter back and forth if it could. And to some degree it actually does.

Have you tried a MUCH more robust fin mounting that has a support strut anchoring the rearmost section of fin/bracket back to the side of tub ?

** Something along these styles ?

Scott:

I had the same problem for years and years with the turn fin mounting system. I have FINALLY found a great answer and it works perfectly on all sized boats.

I bought a piece of 1/8" thick carbon sheet from Aerospace Composites and I make a doubler out of that and make the mounting holes exactly like what the turn fin has. I then use 2 4/40 SHCap Screws throught both pieces and it is totally rigid and will not bend at all. Best of all the carbon has memory that keeps it completely straight. That makes the aluminum fin stay perfectly straight. I suspose that on a really big boat like a twin, etc. you could use 3/16" carbon to make it REALLY STIFF.

Be sure that you put the carbon doubler on the outside of the fin so that the water doesn't find the doubler.

Marty,

But all the lateral loading on fin still transmits itself to the anchor spot ... The Sponson.

So one would think with the leverage involved with the fin being any where from 2" - 5" behind sponson trailing edge or the rear boom, It would really add a lot torsional loading on the boom tubes causing alignment errors expotentionaly as boats speed increases ?

Viewpoint being the angled fin as boat corners has water climbing up the working face of fin, this has a pull down effect on fin and bracket rotating the sponson between the two booms upsetting the AOA of wetted and air surfaces of BOTH sponsons as tub of hull must twist from the torsional load created from the unsupported turn fin.

Am I wrong in my thinking ?

 

[John Finch]

Jeroen,
Been reading on this for months waiting to see a solution

Just an observation and helping suggestion for whats it worth.

Personally NEVER have liked or gotten the rigidity required using sandwiched turnfin & bracket off the inside of sponson. IMO just not robust enough and prone to flutter like a flag in a stiff breeze.

Basically stating that the turn fin running threw the water acts like a flag does in the wind. Even tho the fin is metal and does not flap back and forth like a flag does, the fact it is subjected too such high pressure running threw the water it by design would shutter back and forth if it could. And to some degree it actually does.

Have you tried a MUCH more robust fin mounting that has a support strut anchoring the rearmost section of fin/bracket back to the side of tub ?

** Something along these styles ?

Scott:

I had the same problem for years and years with the turn fin mounting system. I have FINALLY found a great answer and it works perfectly on all sized boats.

I bought a piece of 1/8" thick carbon sheet from Aerospace Composites and I make a doubler out of that and make the mounting holes exactly like what the turn fin has. I then use 2 4/40 SHCap Screws throught both pieces and it is totally rigid and will not bend at all. Best of all the carbon has memory that keeps it completely straight. That makes the aluminum fin stay perfectly straight. I suspose that on a really big boat like a twin, etc. you could use 3/16" carbon to make it REALLY STIFF.

Be sure that you put the carbon doubler on the outside of the fin so that the water doesn't find the doubler.

Marty,

But all the lateral loading on fin still transmits itself to the anchor spot ... The Sponson.

So one would think with the leverage involved with the fin being any where from 2" - 5" behind sponson trailing edge or the rear boom, It would really add a lot torsional loading on the boom tubes causing alignment errors expotentionaly as boats speed increases ?

Viewpoint being the angled fin as boat corners has water climbing up the working face of fin, this has a pull down effect on fin and bracket rotating the sponson between the two booms upsetting the AOA of wetted and air surfaces of BOTH sponsons as tub of hull must twist from the torsional load created from the unsupported turn fin.

Am I wrong in my thinking ?

Just hold your boat in your hands and push on the turnfin. Watch the right sponson move up and down at the tip. Makes you think doesn't it! Your the first person I have ever heard talk of this. It's about time! Kentley Porter and myself spent a lot of time keeping turnfins attached to our oval record trial boats. Try going into a corner at 103 mph and see if the sponson angle changes. That's when I learned about the angle change. Also, when you put your boat on the setup table. Measure sponson angles with the engine, pipe, and fuel in the boat, and then re-measure again without the engine, pipe, and fuel in the boat. These boats are flexable!!!!!!!!. Oh, not all the weight is on the turn fin. It shares it's workload with other parts of the boat.

 

[Scott Schneider]

Jeroen,
Been reading on this for months waiting to see a solution

Just an observation and helping suggestion for whats it worth.

Personally NEVER have liked or gotten the rigidity required using sandwiched turnfin & bracket off the inside of sponson. IMO just not robust enough and prone to flutter like a flag in a stiff breeze.

Basically stating that the turn fin running threw the water acts like a flag does in the wind. Even tho the fin is metal and does not flap back and forth like a flag does, the fact it is subjected too such high pressure running threw the water it by design would shutter back and forth if it could. And to some degree it actually does.

Have you tried a MUCH more robust fin mounting that has a support strut anchoring the rearmost section of fin/bracket back to the side of tub ?

** Something along these styles ?

Scott:

I had the same problem for years and years with the turn fin mounting system. I have FINALLY found a great answer and it works perfectly on all sized boats.

I bought a piece of 1/8" thick carbon sheet from Aerospace Composites and I make a doubler out of that and make the mounting holes exactly like what the turn fin has. I then use 2 4/40 SHCap Screws throught both pieces and it is totally rigid and will not bend at all. Best of all the carbon has memory that keeps it completely straight. That makes the aluminum fin stay perfectly straight. I suspose that on a really big boat like a twin, etc. you could use 3/16" carbon to make it REALLY STIFF.

Be sure that you put the carbon doubler on the outside of the fin so that the water doesn't find the doubler.

Marty,

But all the lateral loading on fin still transmits itself to the anchor spot ... The Sponson.

So one would think with the leverage involved with the fin being any where from 2" - 5" behind sponson trailing edge or the rear boom, It would really add a lot torsional loading on the boom tubes causing alignment errors expotentionaly as boats speed increases ?

Viewpoint being the angled fin as boat corners has water climbing up the working face of fin, this has a pull down effect on fin and bracket rotating the sponson between the two booms upsetting the AOA of wetted and air surfaces of BOTH sponsons as tub of hull must twist from the torsional load created from the unsupported turn fin.

Am I wrong in my thinking ?

Just hold your boat in your hands and push on the turnfin. Watch the right sponson move up and down at the tip. Makes you think doesn't it! Your the first person I have ever heard talk of this. It's about time! Kentley Porter and myself spent a lot of time keeping turnfins attached to our oval record trial boats. Try going into a corner at 103 mph and see if the sponson angle changes. That's when I learned about the angle change. Also, when you put your boat on the setup table. Measure sponson angles with the engine, pipe, and fuel in the boat, and then re-measure again without the engine, pipe, and fuel in the boat. These boats are flexable!!!!!!!!. Oh, not all the weight is on the turn fin. It shares it's workload with other parts of the boat.

In all the years I have been racing riggers have used support struts to beef up the whole right sponson side to help address this issue.

More than once before really beefing up my designs, my support strut has broken from the severe rotational loading I was trying to control. You always know when this happened because straight line tracking along with cornering control got sloppy <_<

 

[Marty Davis]

Jeroen,
Been reading on this for months waiting to see a solution

Just an observation and helping suggestion for whats it worth.

Personally NEVER have liked or gotten the rigidity required using sandwiched turnfin & bracket off the inside of sponson. IMO just not robust enough and prone to flutter like a flag in a stiff breeze.

Basically stating that the turn fin running threw the water acts like a flag does in the wind. Even tho the fin is metal and does not flap back and forth like a flag does, the fact it is subjected too such high pressure running threw the water it by design would shutter back and forth if it could. And to some degree it actually does.

Have you tried a MUCH more robust fin mounting that has a support strut anchoring the rearmost section of fin/bracket back to the side of tub ?

** Something along these styles ?

Scott:

I had the same problem for years and years with the turn fin mounting system. I have FINALLY found a great answer and it works perfectly on all sized boats.

I bought a piece of 1/8" thick carbon sheet from Aerospace Composites and I make a doubler out of that and make the mounting holes exactly like what the turn fin has. I then use 2 4/40 SHCap Screws throught both pieces and it is totally rigid and will not bend at all. Best of all the carbon has memory that keeps it completely straight. That makes the aluminum fin stay perfectly straight. I suspose that on a really big boat like a twin, etc. you could use 3/16" carbon to make it REALLY STIFF.

Be sure that you put the carbon doubler on the outside of the fin so that the water doesn't find the doubler.

Marty,

But all the lateral loading on fin still transmits itself to the anchor spot ... The Sponson.

So one would think with the leverage involved with the fin being any where from 2" - 5" behind sponson trailing edge or the rear boom, It would really add a lot torsional loading on the boom tubes causing alignment errors expotentionaly as boats speed increases ?

Viewpoint being the angled fin as boat corners has water climbing up the working face of fin, this has a pull down effect on fin and bracket rotating the sponson between the two booms upsetting the AOA of wetted and air surfaces of BOTH sponsons as tub of hull must twist from the torsional load created from the unsupported turn fin.

Am I wrong in my thinking ?

Maybe I am doing things differently that most on turn fins.

I don't have problems with the anchor points on my sponsons.

BUT, I set my turn fins so that they act as a pivot point rather than work a lot to throw water. If you look at my boats in the turn, there is virtually no water coming off of the turn fin.

I guess that I am doing things differently than most.....

Marty Davis

 

[Marty Davis]

Jeroen,
Been reading on this for months waiting to see a solution

Just an observation and helping suggestion for whats it worth.

Personally NEVER have liked or gotten the rigidity required using sandwiched turnfin & bracket off the inside of sponson. IMO just not robust enough and prone to flutter like a flag in a stiff breeze.

Basically stating that the turn fin running threw the water acts like a flag does in the wind. Even tho the fin is metal and does not flap back and forth like a flag does, the fact it is subjected too such high pressure running threw the water it by design would shutter back and forth if it could. And to some degree it actually does.

Have you tried a MUCH more robust fin mounting that has a support strut anchoring the rearmost section of fin/bracket back to the side of tub ?

** Something along these styles ?

Scott:

I had the same problem for years and years with the turn fin mounting system. I have FINALLY found a great answer and it works perfectly on all sized boats.

I bought a piece of 1/8" thick carbon sheet from Aerospace Composites and I make a doubler out of that and make the mounting holes exactly like what the turn fin has. I then use 2 4/40 SHCap Screws throught both pieces and it is totally rigid and will not bend at all. Best of all the carbon has memory that keeps it completely straight. That makes the aluminum fin stay perfectly straight. I suspose that on a really big boat like a twin, etc. you could use 3/16" carbon to make it REALLY STIFF.

Be sure that you put the carbon doubler on the outside of the fin so that the water doesn't find the doubler.

Marty,

But all the lateral loading on fin still transmits itself to the anchor spot ... The Sponson.

So one would think with the leverage involved with the fin being any where from 2" - 5" behind sponson trailing edge or the rear boom, It would really add a lot torsional loading on the boom tubes causing alignment errors expotentionaly as boats speed increases ?

Viewpoint being the angled fin as boat corners has water climbing up the working face of fin, this has a pull down effect on fin and bracket rotating the sponson between the two booms upsetting the AOA of wetted and air surfaces of BOTH sponsons as tub of hull must twist from the torsional load created from the unsupported turn fin.

Am I wrong in my thinking ?

Just hold your boat in your hands and push on the turnfin. Watch the right sponson move up and down at the tip. Makes you think doesn't it! Your the first person I have ever heard talk of this. It's about time! Kentley Porter and myself spent a lot of time keeping turnfins attached to our oval record trial boats. Try going into a corner at 103 mph and see if the sponson angle changes. That's when I learned about the angle change. Also, when you put your boat on the setup table. Measure sponson angles with the engine, pipe, and fuel in the boat, and then re-measure again without the engine, pipe, and fuel in the boat. These boats are flexable!!!!!!!!. Oh, not all the weight is on the turn fin. It shares it's workload with other parts of the boat.

John:

I agree with you about the flex. There is a significant amount of change when you push down on various parts of the boat when you have it on the setup table.

I wonder if that is a fair analysis though. If your boat is running the sponsons might move some but they come back to their base setup point. They might actually ocilate some as they hit ripples etc. The rear of the boat does some amount of attitude change, as a result of water conditions, which also changes attack angle.

I have often though about a boat that had the sponsons attached on springs. Actually we have that to some degree now.

Scott:

Not sure that I agree with you about the fin being pulled down. It might be pulled down at some times a little when the attitude changes in the rear. Most times I want my fin to be totally neutral as far as lift. The front changes more than the rear, so if anything the fin is probably lifting more than it is pulling down.

 

[Chris Wood]

Maybe I am doing things differently that most on turn fins.

I don't have problems with the anchor points on my sponsons.

BUT, I set my turn fins so that they act as a pivot point rather than work a lot to throw water. If you look at my boats in the turn, there is virtually no water coming off of the turn fin.

I guess that I am doing things differently than most.....

Marty Davis

your not alone

 

[Scott Schneider]

I understand pivoting on the fin dynamics and C/G positioning to fin relationship

** But there is a HUGE difference in a 6# .21 rigger and a 12# gas rigger in Centrifugal force applied to the fin holding the boat while cornering :huh: