01 Apr 2004 01:49:17
joel
suggestions on making a fin fit correctly

Just got a spiffy new fin but it doesn't fit too well in the fin box.
Actually, I've never had a new fin fit the way I think it should. The fin
is a power box and I'm looking for suggestions on how to fit the fin to the
box as best & as easily as possible. Right now the fin base sticks out of
the box about 3-5mm (depending on if you measure in the front or in the
back). Where do I start? Please help.

Thanks,

joel




01 Apr 2004 01:16:33
Alan Sandoval
Re: suggestions on making a fin fit correctly

What is it about Power Box that manufacturers like? I had nothing but
problems with them. They simply NEVER fit correctly without a lot of
attention. 'Attention' meaning sanding, fitting, more sanding, fitting, and
then more sanding. When I had my shop I literally put hours into getting
one fin to work in a Power Box. I really had better things to do. I HATED
Power Box fins. Great, sell a fin for $90 then spend 3 hours getting it to
fit into the customer board. Sorry, this message pushed a button.

The only advice I have for Joel is to get out the sandpaper, get some of
that blue dye that shows where interference is happening, and spend many
happy hours making your fin fit the box in the board. It shouldn't be like
that. It's carelessness on the part of the board maker or the fin maker.
There is NO reason why your fin shouldn't simply fit in the box on the first
try. Placing blame is up to you, the board maker, or the fin maker, the
fact is someone here is NOT figuring it out, and it isn't the end client.

Good luck Joel


"joel" <wsurf@sbcglobal.net > wrote in message
news:xyKac.42731$PY.3381@newssvr26.news.prodigy.com...
> Just got a spiffy new fin but it doesn't fit too well in the fin box.
> Actually, I've never had a new fin fit the way I think it should. The fin
> is a power box and I'm looking for suggestions on how to fit the fin to
the
> box as best & as easily as possible. Right now the fin base sticks out of
> the box about 3-5mm (depending on if you measure in the front or in the
> back). Where do I start? Please help.
>
> Thanks,
>
> joel
>
>
>




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01 Apr 2004 17:14:11
Florian Feuser /FFF/
Re: suggestions on making a fin fit correctly

On 4/1/04 4:16 AM Alan Sandoval wrote:
> What is it about Power Box that manufacturers like? I had nothing but
> problems with them. They simply NEVER fit correctly without a lot of
> attention. 'Attention' meaning sanding, fitting, more sanding, fitting, and
> then more sanding. When I had my shop I literally put hours into getting
> one fin to work in a Power Box. I really had better things to do. I HATED
> Power Box fins. Great, sell a fin for $90 then spend 3 hours getting it to
> fit into the customer board. Sorry, this message pushed a button.
>
> The only advice I have for Joel is to get out the sandpaper, get some of
> that blue dye that shows where interference is happening, and spend many
> happy hours making your fin fit the box in the board. It shouldn't be like
> that. It's carelessness on the part of the board maker or the fin maker.
> There is NO reason why your fin shouldn't simply fit in the box on the first
> try. Placing blame is up to you, the board maker, or the fin maker, the
> fact is someone here is NOT figuring it out, and it isn't the end client.
>
> Good luck Joel

Just a matter of manufacturing tolerances. The tapered power box design handles
a mis-match more gracefully than other designs.

It's a much harder fix, if the sidewalls in a US base fin are uneven. If the
base is too thin you MUST shim to get a firm fit. On a powerbox, tightening the
screw will get the fin seated firmly - even if the base is a little recessed
against the board surface (you may have to take off a little material from the
top of the fin base).

florian


01 Apr 2004 09:48:42
Andreas Macke
Re: suggestions on making a fin fit correctly

"Alan Sandoval" <alan.s@(removespam)intertrader.net > wrote in message news:<406bde01@127.0.0.1>...

> There is NO reason why your fin shouldn't simply fit in the box on the first
> try. Placing blame is up to you, the board maker, or the fin maker, the
> fact is someone here is NOT figuring it out, and it isn't the end client.
>

That depends on what you're willing to pay, and where your priorities
are. You can get tight tolerances two ways. One is to spend lots of
money on precision tooling and mechanize the process. The second is to
spend lots of labor on making things fit. The first way works for
industries with large economies of scale such as manufacturing cars
where you can spread tooling cost over large numbers to enable pretty
tight tolerances at a reasonable price per piece. The second works for
handmade products with highly skilled craftsmen producing them.

"Mass" produced boards and fins fall somewhere in the middle. They
don't have the numbers to really invest in really precise tooling and
automation. Yet their numbers are too large to effectively control
quality the way a craftsman does.

As a result, you can get fins and boxes that fit super-precisely (no
need for sanding when I get a new Deboichet fin and put it in my
Roberts board; just a super nice fit) if you're buying stuff from
custom makers. Or you can buy production at a lower cost. If that's
what you're doing, you'll end up living with less precise fit and
finish, or you break out the sandpaper or shims to do what they didn't
have time to do in the factory.

Fin box fit is only one of the outcomes affected by the cost/benefit
game of making equipment. It's an obvious one, yet for performance, as
long as the box is true to the length-axis of the board, and true
vertically, and centered, it's not that terribly important. There are
other tolerances that happen in the semi-industrial molding processes
at Cobra that are more significant, but are less obvious. Resin
saturation (too much - too heavy; too little - weak spot with
potential breakage causing a lengthy warranty process or a costly
repair out of your own pocket if not covered or post warranty period)
comes to mind as one that's hard to detect.. Subtle differences in
rocker lines are another (very significant for Formula boards, for
example, and generally no recourse if you discover your board is off
the pace due to a manufacturing tolerance gone wrong). Remember that
fin box fit is only an indicator of the kind of cost-benefit decisions
that have been made about all of those factors, whether obvious or
hard to detect. Buying a product implies your consent to those
decisions.

As for Joel stuck sanding his fin - the above is not meant to make you
feel like a whiner. Instead, it's meant as encouragement to (a)
understand the product purchase decision you made, (b) make you feel
better about having to sand your fin (hey, you got a cheaper board out
of it) and (c) give you some more input the next time you buy a board
so you're expectations can be more realistic.

Andreas
G-42


01 Apr 2004 18:40:13
joel
Re: suggestions on making a fin fit correctly

I understand the whole "get what you pay for" and how tolerance stacking
occurs (I work in manufacturing) I just don't want to spend hours trying to
make it fit by means of sanding only to find I took material off of the
incorrect surfaces and now have to shim those surfaces to make it fit and
still need to remove material in other places. I'm just looking for some
advice as to how to best approach the fitting of the fin. I've tried to use
various methods to mark the fin so I can find the interference with less
success than I would hope for. I don't want to screw up the fin by over
doing it. Is it typical that the fin box is too shallow so it "bottoms out"
in the box or is it more likely that the tapered surfaces are too thick and
thus requires the removal of material? I'm not complaining, I just want to
do this right. Even with the fin base sticking out of the box 3 - 5 mm it
STILL sails excellent. I want to get all I can out of the fin and the only
tweaking it needs is to locate it in the box correctly.

Thanks,

joel



"Andreas Macke" <a_macke@yahoo.com > wrote in message
news:13459a5e.0404010948.2e99fb40@posting.google.com...
> "Alan Sandoval" <alan.s@(removespam)intertrader.net> wrote in message
news:<406bde01@127.0.0.1 >...
>
> > There is NO reason why your fin shouldn't simply fit in the box on the
first
> > try. Placing blame is up to you, the board maker, or the fin maker, the
> > fact is someone here is NOT figuring it out, and it isn't the end
client.
> >
>
> That depends on what you're willing to pay, and where your priorities
> are. You can get tight tolerances two ways. One is to spend lots of
> money on precision tooling and mechanize the process. The second is to
> spend lots of labor on making things fit. The first way works for
> industries with large economies of scale such as manufacturing cars
> where you can spread tooling cost over large numbers to enable pretty
> tight tolerances at a reasonable price per piece. The second works for
> handmade products with highly skilled craftsmen producing them.
>
> "Mass" produced boards and fins fall somewhere in the middle. They
> don't have the numbers to really invest in really precise tooling and
> automation. Yet their numbers are too large to effectively control
> quality the way a craftsman does.
>
> As a result, you can get fins and boxes that fit super-precisely (no
> need for sanding when I get a new Deboichet fin and put it in my
> Roberts board; just a super nice fit) if you're buying stuff from
> custom makers. Or you can buy production at a lower cost. If that's
> what you're doing, you'll end up living with less precise fit and
> finish, or you break out the sandpaper or shims to do what they didn't
> have time to do in the factory.
>
> Fin box fit is only one of the outcomes affected by the cost/benefit
> game of making equipment. It's an obvious one, yet for performance, as
> long as the box is true to the length-axis of the board, and true
> vertically, and centered, it's not that terribly important. There are
> other tolerances that happen in the semi-industrial molding processes
> at Cobra that are more significant, but are less obvious. Resin
> saturation (too much - too heavy; too little - weak spot with
> potential breakage causing a lengthy warranty process or a costly
> repair out of your own pocket if not covered or post warranty period)
> comes to mind as one that's hard to detect.. Subtle differences in
> rocker lines are another (very significant for Formula boards, for
> example, and generally no recourse if you discover your board is off
> the pace due to a manufacturing tolerance gone wrong). Remember that
> fin box fit is only an indicator of the kind of cost-benefit decisions
> that have been made about all of those factors, whether obvious or
> hard to detect. Buying a product implies your consent to those
> decisions.
>
> As for Joel stuck sanding his fin - the above is not meant to make you
> feel like a whiner. Instead, it's meant as encouragement to (a)
> understand the product purchase decision you made, (b) make you feel
> better about having to sand your fin (hey, you got a cheaper board out
> of it) and (c) give you some more input the next time you buy a board
> so you're expectations can be more realistic.
>
> Andreas
> G-42




01 Apr 2004 19:05:08
joel
Re: suggestions on making a fin fit correctly

Oh, by the way, I do believe that board/fin manufacturers should be able to
hold a bit better of tolerance for the fin/board interaction. Not
perfection but, closer than what I've experienced. I'm not pointing fingers
at either manufacturer, just hoping for a tightening of tolerances. If this
means $20-$40 extra per board and an additional $10-$15 per fin to eliminate
it, sign me up (this translates to roughly 20 - 40 minutes per board extra
and 15 - 20 extra minutes per fin in Wisconsin average to above average cost
machine shop, I know machining rates and labor rates vary a bit overseas &
throughout the USA).

joel


"joel" <wsurf@sbcglobal.net > wrote in message
news:hmZac.46383$ah5.31190@newssvr16.news.prodigy.com...
> I understand the whole "get what you pay for" and how tolerance stacking
> occurs (I work in manufacturing) I just don't want to spend hours trying
to
> make it fit by means of sanding only to find I took material off of the
> incorrect surfaces and now have to shim those surfaces to make it fit and
> still need to remove material in other places. I'm just looking for some
> advice as to how to best approach the fitting of the fin. I've tried to
use
> various methods to mark the fin so I can find the interference with less
> success than I would hope for. I don't want to screw up the fin by over
> doing it. Is it typical that the fin box is too shallow so it "bottoms
out"
> in the box or is it more likely that the tapered surfaces are too thick
and
> thus requires the removal of material? I'm not complaining, I just want
to
> do this right. Even with the fin base sticking out of the box 3 - 5 mm it
> STILL sails excellent. I want to get all I can out of the fin and the
only
> tweaking it needs is to locate it in the box correctly.
>
> Thanks,
>
> joel
>
>
>
> "Andreas Macke" <a_macke@yahoo.com> wrote in message
> news:13459a5e.0404010948.2e99fb40@posting.google.com...
> > "Alan Sandoval" <alan.s@(removespam)intertrader.net> wrote in message
> news:<406bde01@127.0.0.1>...
> >
> > > There is NO reason why your fin shouldn't simply fit in the box on the
> first
> > > try. Placing blame is up to you, the board maker, or the fin maker,
the
> > > fact is someone here is NOT figuring it out, and it isn't the end
> client.
> > >
> >
> > That depends on what you're willing to pay, and where your priorities
> > are. You can get tight tolerances two ways. One is to spend lots of
> > money on precision tooling and mechanize the process. The second is to
> > spend lots of labor on making things fit. The first way works for
> > industries with large economies of scale such as manufacturing cars
> > where you can spread tooling cost over large numbers to enable pretty
> > tight tolerances at a reasonable price per piece. The second works for
> > handmade products with highly skilled craftsmen producing them.
> >
> > "Mass" produced boards and fins fall somewhere in the middle. They
> > don't have the numbers to really invest in really precise tooling and
> > automation. Yet their numbers are too large to effectively control
> > quality the way a craftsman does.
> >
> > As a result, you can get fins and boxes that fit super-precisely (no
> > need for sanding when I get a new Deboichet fin and put it in my
> > Roberts board; just a super nice fit) if you're buying stuff from
> > custom makers. Or you can buy production at a lower cost. If that's
> > what you're doing, you'll end up living with less precise fit and
> > finish, or you break out the sandpaper or shims to do what they didn't
> > have time to do in the factory.
> >
> > Fin box fit is only one of the outcomes affected by the cost/benefit
> > game of making equipment. It's an obvious one, yet for performance, as
> > long as the box is true to the length-axis of the board, and true
> > vertically, and centered, it's not that terribly important. There are
> > other tolerances that happen in the semi-industrial molding processes
> > at Cobra that are more significant, but are less obvious. Resin
> > saturation (too much - too heavy; too little - weak spot with
> > potential breakage causing a lengthy warranty process or a costly
> > repair out of your own pocket if not covered or post warranty period)
> > comes to mind as one that's hard to detect.. Subtle differences in
> > rocker lines are another (very significant for Formula boards, for
> > example, and generally no recourse if you discover your board is off
> > the pace due to a manufacturing tolerance gone wrong). Remember that
> > fin box fit is only an indicator of the kind of cost-benefit decisions
> > that have been made about all of those factors, whether obvious or
> > hard to detect. Buying a product implies your consent to those
> > decisions.
> >
> > As for Joel stuck sanding his fin - the above is not meant to make you
> > feel like a whiner. Instead, it's meant as encouragement to (a)
> > understand the product purchase decision you made, (b) make you feel
> > better about having to sand your fin (hey, you got a cheaper board out
> > of it) and (c) give you some more input the next time you buy a board
> > so you're expectations can be more realistic.
> >
> > Andreas
> > G-42
>
>




01 Apr 2004 20:05:00
sailquik (Roger Jackson)
Re: suggestions on making a fin fit correctly

Hi Joel,
Lot's of discussion and a few good suggestions here.
Does the original fin that came with your board fit correctly?
That's the first thing to determine.
If it does, then you can fairly safely assume that the fin box, in your board
was manufactured to the correct tolerances (at least that particular
manufacturer's
interpretation of the tolerances).
So, now you must decide if the reason the fin does not fit is because the
tapers are
too thick, or the end of the root is too long.
If the end of the root is too long, then the fin will wobble sideways in the
box when
you insert it, as the root is preventing the tapers on the fin from engaging
the tapers
on the sides of the fin box.
There is one other possibility here. The tapers/radius on the front and rear of
the fin
are too long.
Also, take a look at the tips of the root, and at the front/rear taper/radius
and see if there
are any major visual differences between your new fin and the replacement fin
you are
trying to fit into your board. If there are major visual differences, and the
stock fin fits
fine, then you know that the new fin is what needs modification.
So, get a bar of bath soap. Rub it vigorously all over the root of the fin.
Notice that the
soap is whitish colored and dull.
Put the fin into the fin box and tighten the screw up lightly. Tap the fin side
to side
and front to back with the heel of your hand, or a small rubber mallet. Just
enough
so that the "high spots" will fully engage.
Remove the fin, and look at the soap on the root. All of the areas that are
still "dull"
and whitish are not making contact. The "shiny and darker areas are where your
fin
is making contact.
Determine if these contact areas are on the tips of the root, the flanks of the
taper, or
perhaps on the front/rear radius/taper.
Use a file and a sanding block to remove a little material in ONLY the areas
that are making
contact.
Repeat this process a few time, and your fin should fit perfectly flush.
If the front of the root is dropping in nicely, but the rear isn't take a
little more off the rear
each time.
Go slowly with the file and sanding block and see how much the fin drops into
the box
each time you remove and file/sand it.
If it's not dropping into the box, file or sand a bit more between fittings.
Remember to rub the soap over the entire fin root each time so you can see
where it's
making contact (the dark and shiny spots).
Yes, it's a pain, but fitting tapers has always been one of "industry's"
hardest things to get
right, consistently.
Just be glad that your new fin has a little extra material for fitting. It's
really a bad situation
when the fin goes into the box too deep and you need to add material to get the
root to fit
correctly.
Hope this helps,
Roger


joel wrote:

> Just got a spiffy new fin but it doesn't fit too well in the fin box.
> Actually, I've never had a new fin fit the way I think it should. The fin
> is a power box and I'm looking for suggestions on how to fit the fin to the
> box as best & as easily as possible. Right now the fin base sticks out of
> the box about 3-5mm (depending on if you measure in the front or in the
> back). Where do I start? Please help.
>
> Thanks,
>
> joel



01 Apr 2004 20:23:03
joel
Re: suggestions on making a fin fit correctly

Thanks Roger. That's similar to what I have been doing but there are some
things I had overlooked. Time to get out the soap...



"sailquik (Roger Jackson)" <sailquik@mindspring.com > wrote in message
news:406C75BE.DEF8A12D@mindspring.com...
> Hi Joel,
> Lot's of discussion and a few good suggestions here.
> Does the original fin that came with your board fit correctly?
> That's the first thing to determine.
> If it does, then you can fairly safely assume that the fin box, in your
board
> was manufactured to the correct tolerances (at least that particular
> manufacturer's
> interpretation of the tolerances).
> So, now you must decide if the reason the fin does not fit is because the
> tapers are
> too thick, or the end of the root is too long.
> If the end of the root is too long, then the fin will wobble sideways in
the
> box when
> you insert it, as the root is preventing the tapers on the fin from
engaging
> the tapers
> on the sides of the fin box.
> There is one other possibility here. The tapers/radius on the front and
rear of
> the fin
> are too long.
> Also, take a look at the tips of the root, and at the front/rear
taper/radius
> and see if there
> are any major visual differences between your new fin and the replacement
fin
> you are
> trying to fit into your board. If there are major visual differences, and
the
> stock fin fits
> fine, then you know that the new fin is what needs modification.
> So, get a bar of bath soap. Rub it vigorously all over the root of the
fin.
> Notice that the
> soap is whitish colored and dull.
> Put the fin into the fin box and tighten the screw up lightly. Tap the fin
side
> to side
> and front to back with the heel of your hand, or a small rubber mallet.
Just
> enough
> so that the "high spots" will fully engage.
> Remove the fin, and look at the soap on the root. All of the areas that
are
> still "dull"
> and whitish are not making contact. The "shiny and darker areas are where
your
> fin
> is making contact.
> Determine if these contact areas are on the tips of the root, the flanks
of the
> taper, or
> perhaps on the front/rear radius/taper.
> Use a file and a sanding block to remove a little material in ONLY the
areas
> that are making
> contact.
> Repeat this process a few time, and your fin should fit perfectly flush.
> If the front of the root is dropping in nicely, but the rear isn't take a
> little more off the rear
> each time.
> Go slowly with the file and sanding block and see how much the fin drops
into
> the box
> each time you remove and file/sand it.
> If it's not dropping into the box, file or sand a bit more between
fittings.
> Remember to rub the soap over the entire fin root each time so you can see
> where it's
> making contact (the dark and shiny spots).
> Yes, it's a pain, but fitting tapers has always been one of "industry's"
> hardest things to get
> right, consistently.
> Just be glad that your new fin has a little extra material for fitting.
It's
> really a bad situation
> when the fin goes into the box too deep and you need to add material to
get the
> root to fit
> correctly.
> Hope this helps,
> Roger
>
>
> joel wrote:
>
> > Just got a spiffy new fin but it doesn't fit too well in the fin box.
> > Actually, I've never had a new fin fit the way I think it should. The
fin
> > is a power box and I'm looking for suggestions on how to fit the fin to
the
> > box as best & as easily as possible. Right now the fin base sticks out
of
> > the box about 3-5mm (depending on if you measure in the front or in the
> > back). Where do I start? Please help.
> >
> > Thanks,
> >
> > joel
>




01 Apr 2004 14:19:51
Craig (gsogh) Goudie
Re: suggestions on making a fin fit correctly

I've had fins where the root was too deep. I've also coated
fin roots with graphite and then wedged them in to see where
they interfere, before I start sanding. And, I've also sanded too far
and then required shimming.

-Craig

joel wrote:

> I understand the whole "get what you pay for" and how tolerance stacking
> occurs (I work in manufacturing) I just don't want to spend hours trying to
> make it fit by means of sanding only to find I took material off of the
> incorrect surfaces and now have to shim those surfaces to make it fit and
> still need to remove material in other places. I'm just looking for some
> advice as to how to best approach the fitting of the fin. I've tried to use
> various methods to mark the fin so I can find the interference with less
> success than I would hope for. I don't want to screw up the fin by over
> doing it. Is it typical that the fin box is too shallow so it "bottoms out"
> in the box or is it more likely that the tapered surfaces are too thick and
> thus requires the removal of material? I'm not complaining, I just want to
> do this right. Even with the fin base sticking out of the box 3 - 5 mm it
> STILL sails excellent. I want to get all I can out of the fin and the only
> tweaking it needs is to locate it in the box correctly.
>
> Thanks,
>
> joel
>
> "Andreas Macke" <a_macke@yahoo.com> wrote in message
> news:13459a5e.0404010948.2e99fb40@posting.google.com...
> > "Alan Sandoval" <alan.s@(removespam)intertrader.net> wrote in message
> news:<406bde01@127.0.0.1>...
> >
> > > There is NO reason why your fin shouldn't simply fit in the box on the
> first
> > > try. Placing blame is up to you, the board maker, or the fin maker, the
> > > fact is someone here is NOT figuring it out, and it isn't the end
> client.
> > >
> >
> > That depends on what you're willing to pay, and where your priorities
> > are. You can get tight tolerances two ways. One is to spend lots of
> > money on precision tooling and mechanize the process. The second is to
> > spend lots of labor on making things fit. The first way works for
> > industries with large economies of scale such as manufacturing cars
> > where you can spread tooling cost over large numbers to enable pretty
> > tight tolerances at a reasonable price per piece. The second works for
> > handmade products with highly skilled craftsmen producing them.
> >
> > "Mass" produced boards and fins fall somewhere in the middle. They
> > don't have the numbers to really invest in really precise tooling and
> > automation. Yet their numbers are too large to effectively control
> > quality the way a craftsman does.
> >
> > As a result, you can get fins and boxes that fit super-precisely (no
> > need for sanding when I get a new Deboichet fin and put it in my
> > Roberts board; just a super nice fit) if you're buying stuff from
> > custom makers. Or you can buy production at a lower cost. If that's
> > what you're doing, you'll end up living with less precise fit and
> > finish, or you break out the sandpaper or shims to do what they didn't
> > have time to do in the factory.
> >
> > Fin box fit is only one of the outcomes affected by the cost/benefit
> > game of making equipment. It's an obvious one, yet for performance, as
> > long as the box is true to the length-axis of the board, and true
> > vertically, and centered, it's not that terribly important. There are
> > other tolerances that happen in the semi-industrial molding processes
> > at Cobra that are more significant, but are less obvious. Resin
> > saturation (too much - too heavy; too little - weak spot with
> > potential breakage causing a lengthy warranty process or a costly
> > repair out of your own pocket if not covered or post warranty period)
> > comes to mind as one that's hard to detect.. Subtle differences in
> > rocker lines are another (very significant for Formula boards, for
> > example, and generally no recourse if you discover your board is off
> > the pace due to a manufacturing tolerance gone wrong). Remember that
> > fin box fit is only an indicator of the kind of cost-benefit decisions
> > that have been made about all of those factors, whether obvious or
> > hard to detect. Buying a product implies your consent to those
> > decisions.
> >
> > As for Joel stuck sanding his fin - the above is not meant to make you
> > feel like a whiner. Instead, it's meant as encouragement to (a)
> > understand the product purchase decision you made, (b) make you feel
> > better about having to sand your fin (hey, you got a cheaper board out
> > of it) and (c) give you some more input the next time you buy a board
> > so you're expectations can be more realistic.
> >
> > Andreas
> > G-42

--
Craig (Go Short or Go Home!) Goudie
Sailing the high desert lakes of Utah on my:
RRD 298, Starboard 272 and Cross M 8'2" with
Sailworks/Naish Sails and Rec Composites Fins
Sailing the Gorge on my: 9'1" RRD Freeride,
8'3" Logosz Squish, 8'0" Hitech IBM with
Sailworks/Northwave Sails and Curtis Fins




02 Apr 2004 00:18:09
Bill
Re: suggestions on making a fin fit correctly

>> Use a file and a sanding block to remove a little material in ONLY
>> the areas that are making

I was able to help someone who had labored long and hard to fit a fin, by
suggesting as did Roger that he use a file, rather than sand paper. The
file helped him get close quite quickly, when he had been sanding with no
success. It took minutes not hours.

I have had less success with tuttle fittings than powerbox. In one case,
the custom mfr had painted the inside of the fin box. In another, the fin
fits well but eventually sinks into the deep box, so I have to put a spacer
underneath.





02 Apr 2004 06:28:14
John Sitka
Re: suggestions on making a fin fit correctly

spacers "underneath" tuttle fins?

"Bill" <utthitaxpam@hotmail.com > wrote in message
news:c4itfe$2k8j9p$1@ID-127845.news.uni-berlin.de...
> >> Use a file and a sanding block to remove a little material in ONLY
> >> the areas that are making
>
> I was able to help someone who had labored long and hard to fit a fin, by
> suggesting as did Roger that he use a file, rather than sand paper. The
> file helped him get close quite quickly, when he had been sanding with no
> success. It took minutes not hours.
>
> I have had less success with tuttle fittings than powerbox. In one case,
> the custom mfr had painted the inside of the fin box. In another, the fin
> fits well but eventually sinks into the deep box, so I have to put a
spacer
> underneath.
>
>
>




02 Apr 2004 14:35:01
sailquik (Roger Jackson)
Re: suggestions on making a fin fit correctly

Hi Bill,
Yes, the file works more quickly (they come in many shapes, single cut, double
cut, and special tooth configurations for softer or harder materials).
Also the file can be used more precisely to take off
ONLY the dark shiny high spots that the soap shows.
Wish we had a bigger market as I would like to develop an file or perhaps a
special grinder that would "dress" the radius/angle on the front and rear of a
Tuttle cavity.
Often the reason that a Tuttle fin doesn't fit is some small lump of filler or
paint down on these front/rear radius/angle. If you could easily "dress" off
the lump and dress grind the angles accurately,
to a standard dimension, built into the grinding fixture, fitting a Tuttle or
Deep Tuttle would be fast and easy.
Power box would be more difficult, but not impossible.
Roger

Bill wrote:

> >> Use a file and a sanding block to remove a little material in ONLY
> >> the areas that are making
>
> I was able to help someone who had labored long and hard to fit a fin, by
> suggesting as did Roger that he use a file, rather than sand paper. The
> file helped him get close quite quickly, when he had been sanding with no
> success. It took minutes not hours.
>
> I have had less success with tuttle fittings than powerbox. In one case,
> the custom mfr had painted the inside of the fin box. In another, the fin
> fits well but eventually sinks into the deep box, so I have to put a spacer
> underneath.



02 Apr 2004 14:48:47
sailquik (Roger Jackson)
Re: suggestions on making a fin fit correctly

Hi John,
I agree.
Putting a spacer under a Tuttle fin is not such a good idea.
The Tuttle "system" depends on a tight fit on the sides of the fin root, and a
little "draw" on the front and rear taper/radius to accurately locate the fin.
If the fin goes in too far, the front and rear tapers are not engaging with the
front and rear of the fin box correctly and need to be "built up" slightly to
get the fin located more accurately.
If you use a spacer, to hold the fin up, then the fin is absolutely going to be
"loose" in the fin box.
Best way to build up the fin root is to wipe a thin layer of thickened epoxy or
a product like Marine Tex/JB weld, and then tape it tightly. When the epoxy or
filler cures take the tape off (the tape holds the filler material on the radius
and will distribute the filler smoothly and in the correct radius/shape so you
won't have much filing and sanding to do.
This should bring the fin UP in the fin box. If not enough, then add another
thin layer until the fin roots sits about 1/32" above the bottom of your board.
Then lightly file/sand until it's about 1/64"
above the board's bottom surface.
The last 1/64" is the "draw". If you pull the fin into the box with with the
screws, the "draw" on the tapers will securely and positively "retain" the fin
at the correct height.
A correctly fitted fin, "drawn" into the tapers of the fin box, with a high
percentage of surface engagement, will stay in the board retained by the tapers
alone. The fin screw (s) are simply a "back up" retention system on a correctly
fitted fin.
Hope this helps,
Roger

John Sitka wrote:

> spacers "underneath" tuttle fins?
>
> "Bill" <utthitaxpam@hotmail.com> wrote in message
> news:c4itfe$2k8j9p$1@ID-127845.news.uni-berlin.de...
> > >> Use a file and a sanding block to remove a little material in ONLY
> > >> the areas that are making
> >
> > I was able to help someone who had labored long and hard to fit a fin, by
> > suggesting as did Roger that he use a file, rather than sand paper. The
> > file helped him get close quite quickly, when he had been sanding with no
> > success. It took minutes not hours.
> >
> > I have had less success with tuttle fittings than powerbox. In one case,
> > the custom mfr had painted the inside of the fin box. In another, the fin
> > fits well but eventually sinks into the deep box, so I have to put a
> spacer
> > underneath.
> >
> >
> >



02 Apr 2004 18:14:18
srm
Re: suggestions on making a fin fit correctly

" > front and rear of the fin box correctly and need to be "built up"
slightly to
> get the fin located more accurately.
> If you use a spacer, to hold the fin up, then the fin is absolutely going to be
> "loose" in the fin box.
> Best way to build up the fin root is to wipe a thin layer of thickened epoxy or
> a product like Marine Tex/JB weld, and then tape it tightly.

Here'a a better way to build up the fin root that requires less
sanding and a more accurate fit.
Get a piece of parafin wax and rub the front and back edges of the box
to get a thin coating. If the sides of the fin are loose, wax the
sides of the box too. Lightly sand the front back, and sides of the
fin base (to improve adhesion). Smear Marine Tex on the surfaces of
the fin base and insert the fin into the fin box, leaving about a
1/16" of the base sticking above the bottom of the board. Wipe away
any Marine Tex that has squirted out onto the board. The Marine Tex
will conform exactly to your board's fin box and stick to the fin
base, but not to the box. Once the Marine Tex has cured, one good
"Thwap" should get the fin loose. A little sanding to perfect the fit
and you're set. No shims required. Note: sometimes this requires a
second application if there are voids, but after that, your done- the
perfect fit. I've used this technique for several years with total
success.


03 Apr 2004 05:49:24
Juan
Re: suggestions on making a fin fit correctly

Hi there.

At what point should I worry about fin fit not being perfect?

My deep-tuttle fin goes into the box about 1/16" too deep, only in the
back; the front is leveled with the board. Do you think I'm loosing
performance and should go through the trouble of shimming it?

Thanks,

++*Juan--


sailquik (Roger Jackson) wrote:

> Hi John,
> I agree.
> Putting a spacer under a Tuttle fin is not such a good idea.
> The Tuttle "system" depends on a tight fit on the sides of the fin root, and a
> little "draw" on the front and rear taper/radius to accurately locate the fin.
> If the fin goes in too far, the front and rear tapers are not engaging with the
> front and rear of the fin box correctly and need to be "built up" slightly to
> get the fin located more accurately.
> If you use a spacer, to hold the fin up, then the fin is absolutely going to be
> "loose" in the fin box.
> Best way to build up the fin root is to wipe a thin layer of thickened epoxy or
> a product like Marine Tex/JB weld, and then tape it tightly. When the epoxy or
> filler cures take the tape off (the tape holds the filler material on the radius
> and will distribute the filler smoothly and in the correct radius/shape so you
> won't have much filing and sanding to do.
> This should bring the fin UP in the fin box. If not enough, then add another
> thin layer until the fin roots sits about 1/32" above the bottom of your board.
> Then lightly file/sand until it's about 1/64"
> above the board's bottom surface.
> The last 1/64" is the "draw". If you pull the fin into the box with with the
> screws, the "draw" on the tapers will securely and positively "retain" the fin
> at the correct height.
> A correctly fitted fin, "drawn" into the tapers of the fin box, with a high
> percentage of surface engagement, will stay in the board retained by the tapers
> alone. The fin screw (s) are simply a "back up" retention system on a correctly
> fitted fin.
> Hope this helps,
> Roger
>
> John Sitka wrote:
>
>
>>spacers "underneath" tuttle fins?
>>
>>"Bill" <utthitaxpam@hotmail.com> wrote in message
>>news:c4itfe$2k8j9p$1@ID-127845.news.uni-berlin.de...
>>
>>>>>Use a file and a sanding block to remove a little material in ONLY
>>>>>the areas that are making
>>>
>>>I was able to help someone who had labored long and hard to fit a fin, by
>>>suggesting as did Roger that he use a file, rather than sand paper. The
>>>file helped him get close quite quickly, when he had been sanding with no
>>>success. It took minutes not hours.
>>>
>>>I have had less success with tuttle fittings than powerbox. In one case,
>>>the custom mfr had painted the inside of the fin box. In another, the fin
>>>fits well but eventually sinks into the deep box, so I have to put a
>>
>>spacer
>>
>>>underneath.
>>>
>>>
>>>
>
>

--
++*Juan--


03 Apr 2004 16:20:15
sailquik (Roger Jackson)
Re: suggestions on making a fin fit correctly

Hi Juan,
I'm not sure if there is a significant performance loss. I do know that the pro
formula racers are now "tilting" their deep Tuttle fins in the box to check out
different leading edge angles.
But to bring your fin up at the back, and see if it feels better takes no time at all.

Just get some clear packing tape, or the thicker polyurethane sail repair tape, and
put a strip of it down the rear radius of your fin. Check the fit.
If it needs another strip or two of tape, to bring it up slightly higher than the
bottom of the board (so you will have a slight amount of "draw" with the screws).
Try this and then go sail your board and see if you notice any difference.
If there is a difference, then you can simply leave the tape on the rear of the fin as
a shim, or figure out how thick the tape in and epoxy glue a more permanent shim in
the same place. Or build it up as I suggested in the previous post.
Hope this helps,
Roger

Juan wrote:

> Hi there.
>
> At what point should I worry about fin fit not being perfect?
>
> My deep-tuttle fin goes into the box about 1/16" too deep, only in the
> back; the front is leveled with the board. Do you think I'm loosing
> performance and should go through the trouble of shimming it?
>
> Thanks,
>
> ++*Juan--
>
> sailquik (Roger Jackson) wrote:
>
> > Hi John,
> > I agree.
> > Putting a spacer under a Tuttle fin is not such a good idea.
> > The Tuttle "system" depends on a tight fit on the sides of the fin root, and a
> > little "draw" on the front and rear taper/radius to accurately locate the fin.
> > If the fin goes in too far, the front and rear tapers are not engaging with the
> > front and rear of the fin box correctly and need to be "built up" slightly to
> > get the fin located more accurately.
> > If you use a spacer, to hold the fin up, then the fin is absolutely going to be
> > "loose" in the fin box.
> > Best way to build up the fin root is to wipe a thin layer of thickened epoxy or
> > a product like Marine Tex/JB weld, and then tape it tightly. When the epoxy or
> > filler cures take the tape off (the tape holds the filler material on the radius
> > and will distribute the filler smoothly and in the correct radius/shape so you
> > won't have much filing and sanding to do.
> > This should bring the fin UP in the fin box. If not enough, then add another
> > thin layer until the fin roots sits about 1/32" above the bottom of your board.
> > Then lightly file/sand until it's about 1/64"
> > above the board's bottom surface.
> > The last 1/64" is the "draw". If you pull the fin into the box with with the
> > screws, the "draw" on the tapers will securely and positively "retain" the fin
> > at the correct height.
> > A correctly fitted fin, "drawn" into the tapers of the fin box, with a high
> > percentage of surface engagement, will stay in the board retained by the tapers
> > alone. The fin screw (s) are simply a "back up" retention system on a correctly
> > fitted fin.
> > Hope this helps,
> > Roger
> >
> > John Sitka wrote:
> >
> >
> >>spacers "underneath" tuttle fins?
> >>
> >>"Bill" <utthitaxpam@hotmail.com> wrote in message
> >>news:c4itfe$2k8j9p$1@ID-127845.news.uni-berlin.de...
> >>
> >>>>>Use a file and a sanding block to remove a little material in ONLY
> >>>>>the areas that are making
> >>>
> >>>I was able to help someone who had labored long and hard to fit a fin, by
> >>>suggesting as did Roger that he use a file, rather than sand paper. The
> >>>file helped him get close quite quickly, when he had been sanding with no
> >>>success. It took minutes not hours.
> >>>
> >>>I have had less success with tuttle fittings than powerbox. In one case,
> >>>the custom mfr had painted the inside of the fin box. In another, the fin
> >>>fits well but eventually sinks into the deep box, so I have to put a
> >>
> >>spacer
> >>
> >>>underneath.
> >>>
> >>>
> >>>
> >
> >
>
> --
> ++*Juan--