question? how to draw a fish tail (swallow)

General Discussion
1

Hi everyone

Another question regarding retro fish : I am kind of lost on how to draw the swallow tail for a fish. the tail might be 6" to 8" deep, how do you handle the curve when drawing, do you use a caliper for drawing the curve?

Don’t hesitate to share your ideas!!!Thank you again for considering this request.

2

You could use a section of a spin-template or, as I do, trace the contour of a nice longboard fin.

But french curves will do nicely too.

3

thanks for the info, where can I find those french curves, I know what it looks like, I saw it in the construction and design 1977 book but never saw that tool for real. Is it easy to build one? got no clue.

Thanks for helping out

4

Arts and crafts type shop.

5

Tracing a longboard fin, I like! - Thanks!

6

Someone here once posted that they used the curve of a garbage-can lid to create the curve of the swallow-tail.

Wish I could remember who did it, to give them appropriate credit, since I consider it quite a smart idea.

7

Oceanpearl, Actually anything with a curve on it has the potential to be the right curve for your fish tail. Paint can lids, a drafting compass, etc. French curves are nice because they have an increasingly tighter curve and you can slide them around until they look just right. (That’s how they do it in France…right Balsa?)

You can also just free-hand one side onto a piece of paper, cut it out, mark one side. Then flip it over to mark the other side. I keep the cardboard backing off of yellow legal pads that I use at work. Thin, stiff cardboard that works great for cutting shapes. And they are durable enough to keep.

Doug

8

nose/tail of existing templates or fins…fins are easier because they are small and easy to trace (hold in one hand)

9

Let’s see thaty could get technical…hummmm…

I use a lid from a POPCORN/I-SCREAM bucket…or …a trashcan lid…sometimes a bottom curve of a 5gal. bucket…

Rocket science at it’s best !

H

10

COOPERFISH posted trashcan lid.

I posted i-scream(icecream) lid.

That was some years ago…lol.

H

11
Quote:

French curves are nice because they have an increasingly tighter curve and you can slide them around until they look just right.

Doug

You can do the same with any curve,including bucket lids.

Remember,there are no straight lines in nature.

H

12

Aloha OCEANPERL:

I have a set of Copenhagen Ships Curves that I use for this task. They are hard to find these days but used to be made by Kohinoor. They really are invaluable for this task because much like a French Curve the curve is progressive which I find works great for a swallowtail.

Here is a link to an image showing the full set of curves. It would not be very hard to enlarge some of these and make your own. I have this full set but mainly use the first couple in the second row of the image.

http://www.macnaughtongroup.com/copenhagen_ships_curves.htm

-Robin

13

If your nose template isn’t too ‘‘round’’, use that curve for the inside of the swallow.

It will lend a ‘‘symmetry’’ to the outline that really looks nice. Don’t tell anyone I told

you this…

Oh, this is the internet, I guess it’s not a secret anymore!

14

Thank you so much for having considered my request and for those tips!!!Just great and I do really appreciate your kind help.

I did think of the bucket lid as well but I did not like the curve too much.

The thing with the nose outline is just the thing I was looking for, the symetry is cool.

15

Hey Oceanpearl,

The way I was taught by a seasoned old school foamsmith was to use the curves of a fin !!!

Could be a LB fin, old school single fin … now I have a heap of single fin templates made up for the deed

Some of the best results I’ve had came from the acutual fins being glassed to the board… keeps all the curves and flow related

W

16

upper end of a fishin pole

AKA bendy flexy stick

17

Hi

I always use a half template taken from the nose of the board in question - trace the outline, cut out of thin card and line up with the stringer - gives a nice progressive curve…think I read it somewhere on Swaylocks before - may be a real traditional way of doing it - gives a nice look to the board as common curves are utilised - I’ve also started setting the crack at only 5" as it gives a bit more area under the tail to help when paddling into waves.

Cheers

Richard

18

tnx for the infos :

so you would rather consider a depth of 5" instead of the 6" or 8" I wanted to use for the inside tip of the swallowtail.

Now I am kind of moving to another aspect of the tail, the swallows function like fins when turning, so what it the smartest shape for the tail, too boxy would be a mistake, I guess it must be rather thin like a blade but up to what point and what section of the tail.

I wanted to have it boxy in the stringer area and then thin towards the rails.

Tnx for any feedback

Cheers

19

I try to remember… the tails are rails, not fins. It should be foiled and thinned, but still stay a rail shape, both inside the crack, and outside. I’ll roll the deck down into the rail, so it’s still flat on the deck side of the tails.

20

Please have a look at that thread about shaping a 5’11 fish

http://www.swaylocks.com/forum/gforum.cgi?post=157021;search_string=shape%20swallowtail;guest=18594412#157021

Halsose made that comment regarding the tail acting like a fin.

I am rookie so I am learning and I am not trying to come with facts.

I did indeed think when turning with the tail it would somehow act like a fin eventhough it is a rail but to me a fin is somehow a rail.