>>> Cripes I'm getting confused again when I thought that Rob had me > straightened out.If I blindfolded you and changed the cant and toe in > would you know the difference??????......R.B. Toed in = smaller turning radius, looser No Toe = less drag (going straight), goes straight faster More cant = more lift on tail, less resistance to turning, more drag (on fins) Less cant = less drag (on fins), less lift (more drag on tail)
>>> I'm not sure I agree with that in full, use extremes... what if you put in > 60 degrees cant... what about 90. You'd get plenty of lift, but it > wouldn't hold worth a dam. -- Rook, you`re right. Taken to extremes... at 45 degrees cant the potential for lift begins to overcome any gains in hold... very noticeable at higher speeds. Beyond 45 degrees, such a fin definitely "won`t hold worth a damn", but will provide lots of (unwanted) lift.
>>> Toed in = smaller turning radius, looser No Toe = less drag (going > straight), goes straight faster>>> More cant = more lift on tail, less resistance to turning, more drag (on > fins) Less cant = less drag (on fins), less lift (more drag on tail) Let's put it this way to much of anything is bad... To much toe is slow.. to much cant you would screw with control of the tail...
>>> Yes, big time! I just "cant" figure this stuff out.After 40 plus years I'm still trying to figure out why fins look like the dorsal on a dolphin.I bet the grand industry total spent on fin research adds up maybe 100 bucks.But seriously guys the input did help.thanks.....R.B.
Tom, Does your system allow for adjustment in Cant and Toe-in (Camber?) or is it a fore and aft movement that can be adjusted? Do you have any idea how to set up an adjustable Cant fin system? I've been playing with a fin testing tank and having the ability to adjust Cant and Toe-in while working with a particular foil would benefit the number of results per day documented. For Rich, I have been playing with a variation of Cheyne's Star fin. Picture splitting the fin down the 'Y' axis; reducing the size of the fin to your standard Thruster size and setting up these rail fins per the standard industry method. It is different -- I am not certain that it is better. The foil of the split Y impacts results. It is in it's infancy as I do not have the luxury to work on it on a regular basis. I've been working everyday since Thanksgiving(Santa wears Brown) and have missed loggin' in to Sways, hitting the water and working with the fins. I have two boards sittin' I have needed to glass for over 4 weeks! I finally have the time to hit the water this Sunday. I was given a 1978 Natural Progression Single Fin Pintail to repair, so I will 'test' it tommorrow. Blackies might be the ticket. You gonna be there Steve? This is great thread. Keep it up guys. Magoo
>>> Tom, Does your system allow for adjustment in Cant and Toe-in (Camber?) or > is it a fore and aft movement that can be adjusted? Do you have any idea > how to set up an adjustable Cant fin system? I've been playing with a fin > testing tank and having the ability to adjust Cant and Toe-in while > working with a particular foil would benefit the number of results per day > documented.>>> For Rich,>>> I have been playing with a variation of Cheyne's Star fin. Picture > splitting the fin down the 'Y' axis; reducing the size of the fin to your > standard Thruster size and setting up these rail fins per the standard > industry method.>>> It is different -- I am not certain that it is better. The foil of the > split Y impacts results. It is in it's infancy as I do not have the luxury > to work on it on a regular basis.>>> I've been working everyday since Thanksgiving(Santa wears Brown) and have > missed loggin' in to Sways, hitting the water and working with the fins. I > have two boards sittin' I have needed to glass for over 4 weeks! I finally > have the time to hit the water this Sunday.>>> I was given a 1978 Natural Progression Single Fin Pintail to repair, so I > will 'test' it tommorrow. Blackies might be the ticket. You gonna be there > Steve?>>> This is great thread. Keep it up guys.>>> Magoo Magoo, Red X is adjustable fore and aft only after installation is complete. But, due to the sixe of the box and installation process, it is very setable in cant and camber variation regardless of the bottom contour. Variable camber systems todate require a vary flat surface due to the configuration of the mounting systems. I've only seen one variable cant system. But, it had a seperate lower fin foil segment that could be interchanged to vary the cant. But, you loose rigidity. I supose you could say that by varying the rigidity of the fin itself would be a method for varying the cant under load.
>>> Magoo,>>> Red X is adjustable fore and aft only after installation is complete. But, > due to the sixe of the box and installation process, it is very setable in > cant and camber variation regardless of the bottom contour. Variable > camber systems todate require a vary flat surface due to the configuration > of the mounting systems. I've only seen one variable cant system. But, it > had a seperate lower fin foil segment that could be interchanged to vary > the cant. But, you loose rigidity. I supose you could say that by varying > the rigidity of the fin itself would be a method for varying the cant > under load. I was wondering if you could mold fins with different cant in them.Future fins have this built in but only in one angle(I think)........R.B.
Regarding the "Cant" issue and whether we have resolved its affect on performance, I'm still hedging on whether the issue has been resolved in the thread above, but it does seem to me that as rail fins are laid over toward the rail you do facilitate a more flowing change from rail to rail. Certainly negative cant can't do anything for board performance. No cant probably produces the most holding power but doesn’t allow the board to flow as well. I wonder how much cant Laird has on the rail fins of the tow-in boards we see him going in excess of 45 knots on. Tom, I think that your system will allow the builder to set the fin box with a cant appropriate to a board’s bottom configuration because the mounting system penetrates the entire board, though I may be wrong. With the Future system the fin box is mounted flush with the bottom of the board and one can build cant into a rail fin set as one chooses. The same thing can be done with the Red X system of course, though it's more difficult to do because of the shape of the fin insert and the mounting mechanism is more complex. Magoo, I wonder about the merit of cutting the original starfin down because the foil of the fin, to me at least, is its ultimate common denominator. A poorly foiled fin is junk as far as I'm concerned, though we less and less of them in this day of the mold. I'm working on a modified starfin myself but am starting from scratch with construction. The template is very different from the original though the wing angles have to be the same as the original for the fin to be functional IMHO. I'll be making a center and trying it by itself as well as putting small rail bites with it as the profile is smaller that the original. I'll also be making a set of rail starfins and have some other ideas for rail fin patterns in the works. The ideas continue to come. As with you there isn't enough time for me to do as much experimenting as I would like to. Gone Surfin', Rich
>>> Cripes I'm getting confused again when I thought that Rob had me > straightened out.If I blindfolded you and changed the cant and toe in > would you know the difference??????......R.B. Toed in = smaller turning radius, looser No Toe = less drag (going straight), goes straight faster More cant = more lift on tail, less resistance to turning, more drag (on fins) Less cant = less drag (on fins), less lift (more drag on tail)
>>> I'm not sure I agree with that in full, use extremes... what if you put in > 60 degrees cant... what about 90. You'd get plenty of lift, but it > wouldn't hold worth a dam. -- Rook, you`re right. Taken to extremes... at 45 degrees cant the potential for lift begins to overcome any gains in hold... very noticeable at higher speeds. Beyond 45 degrees, such a fin definitely "won`t hold worth a damn", but will provide lots of (unwanted) lift.
>>> Toed in = smaller turning radius, looser No Toe = less drag (going > straight), goes straight faster>>> More cant = more lift on tail, less resistance to turning, more drag (on > fins) Less cant = less drag (on fins), less lift (more drag on tail) Let's put it this way to much of anything is bad... To much toe is slow.. to much cant you would screw with control of the tail...
>>> If I blindfolded you and changed the cant and toe in > would you know the difference??????......R.B. Yes, big time!
>>> Yes, big time! .........I can too!Herb
>>> Yes, big time! I just "cant" figure this stuff out.After 40 plus years I'm still trying to figure out why fins look like the dorsal on a dolphin.I bet the grand industry total spent on fin research adds up maybe 100 bucks.But seriously guys the input did help.thanks.....R.B.
Tom, Does your system allow for adjustment in Cant and Toe-in (Camber?) or is it a fore and aft movement that can be adjusted? Do you have any idea how to set up an adjustable Cant fin system? I've been playing with a fin testing tank and having the ability to adjust Cant and Toe-in while working with a particular foil would benefit the number of results per day documented. For Rich, I have been playing with a variation of Cheyne's Star fin. Picture splitting the fin down the 'Y' axis; reducing the size of the fin to your standard Thruster size and setting up these rail fins per the standard industry method. It is different -- I am not certain that it is better. The foil of the split Y impacts results. It is in it's infancy as I do not have the luxury to work on it on a regular basis. I've been working everyday since Thanksgiving(Santa wears Brown) and have missed loggin' in to Sways, hitting the water and working with the fins. I have two boards sittin' I have needed to glass for over 4 weeks! I finally have the time to hit the water this Sunday. I was given a 1978 Natural Progression Single Fin Pintail to repair, so I will 'test' it tommorrow. Blackies might be the ticket. You gonna be there Steve? This is great thread. Keep it up guys. Magoo
>>> Tom, Does your system allow for adjustment in Cant and Toe-in (Camber?) or > is it a fore and aft movement that can be adjusted? Do you have any idea > how to set up an adjustable Cant fin system? I've been playing with a fin > testing tank and having the ability to adjust Cant and Toe-in while > working with a particular foil would benefit the number of results per day > documented.>>> For Rich,>>> I have been playing with a variation of Cheyne's Star fin. Picture > splitting the fin down the 'Y' axis; reducing the size of the fin to your > standard Thruster size and setting up these rail fins per the standard > industry method.>>> It is different -- I am not certain that it is better. The foil of the > split Y impacts results. It is in it's infancy as I do not have the luxury > to work on it on a regular basis.>>> I've been working everyday since Thanksgiving(Santa wears Brown) and have > missed loggin' in to Sways, hitting the water and working with the fins. I > have two boards sittin' I have needed to glass for over 4 weeks! I finally > have the time to hit the water this Sunday.>>> I was given a 1978 Natural Progression Single Fin Pintail to repair, so I > will 'test' it tommorrow. Blackies might be the ticket. You gonna be there > Steve?>>> This is great thread. Keep it up guys.>>> Magoo Magoo, Red X is adjustable fore and aft only after installation is complete. But, due to the sixe of the box and installation process, it is very setable in cant and camber variation regardless of the bottom contour. Variable camber systems todate require a vary flat surface due to the configuration of the mounting systems. I've only seen one variable cant system. But, it had a seperate lower fin foil segment that could be interchanged to vary the cant. But, you loose rigidity. I supose you could say that by varying the rigidity of the fin itself would be a method for varying the cant under load.
>>> Magoo,>>> Red X is adjustable fore and aft only after installation is complete. But, > due to the sixe of the box and installation process, it is very setable in > cant and camber variation regardless of the bottom contour. Variable > camber systems todate require a vary flat surface due to the configuration > of the mounting systems. I've only seen one variable cant system. But, it > had a seperate lower fin foil segment that could be interchanged to vary > the cant. But, you loose rigidity. I supose you could say that by varying > the rigidity of the fin itself would be a method for varying the cant > under load. I was wondering if you could mold fins with different cant in them.Future fins have this built in but only in one angle(I think)........R.B.
Regarding the "Cant" issue and whether we have resolved its affect on performance, I'm still hedging on whether the issue has been resolved in the thread above, but it does seem to me that as rail fins are laid over toward the rail you do facilitate a more flowing change from rail to rail. Certainly negative cant can't do anything for board performance. No cant probably produces the most holding power but doesn’t allow the board to flow as well. I wonder how much cant Laird has on the rail fins of the tow-in boards we see him going in excess of 45 knots on. Tom, I think that your system will allow the builder to set the fin box with a cant appropriate to a board’s bottom configuration because the mounting system penetrates the entire board, though I may be wrong. With the Future system the fin box is mounted flush with the bottom of the board and one can build cant into a rail fin set as one chooses. The same thing can be done with the Red X system of course, though it's more difficult to do because of the shape of the fin insert and the mounting mechanism is more complex. Magoo, I wonder about the merit of cutting the original starfin down because the foil of the fin, to me at least, is its ultimate common denominator. A poorly foiled fin is junk as far as I'm concerned, though we less and less of them in this day of the mold. I'm working on a modified starfin myself but am starting from scratch with construction. The template is very different from the original though the wing angles have to be the same as the original for the fin to be functional IMHO. I'll be making a center and trying it by itself as well as putting small rail bites with it as the profile is smaller that the original. I'll also be making a set of rail starfins and have some other ideas for rail fin patterns in the works. The ideas continue to come. As with you there isn't enough time for me to do as much experimenting as I would like to. Gone Surfin', Rich
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