How I Shape Swallow Tails.....

I butchered my first couple swallow tails.
They surf so good but are a hassle to shape.
Here is the culmination of what I have learned as far as shaping the things…

First, cut out your rough shape… I like to make mine 1 1/4" deep on shortboards. That depth seems to “look” right to me.
After it’s cut out, I use this rasp to work on the stringer. I ordered this rasp from FoamEZ iirc. Set the corner of the cutting edge in the center of the stringer and work it back and forth until you got a groove going down the CENTER of your stringer. I shoot for about a 45* angle on this. This part takes a little practice so just go slowly. As you are creating your groove, if it is off-center a little, you can cheat back to center as you make your passes… I am shooting for a flat, straight groove. I make a point NOT to make a curve.

My apologies, the first pic was taken after I had already rough cut and worked on the stringer a bit but, you get the picture…

Here’s another closeup pic of the rasp that I use.
It’s got a blade similar to those aftermarket Sureform blades.
And, here’s a couple pics of what your groove in your stringer should look like.
Like I mentioned before, I shoot for an angle of about 45* and if you notice, I left about 1/4" of stringer untouched on the bottom.

Next I use a hard sanding block.
In pic 2, you can see the groove that I made with the rasp. Use that groove as a guide for your sanding block. Set the corner of your sanding block in there and slowly go back and forth.
In pic 3, you can see what I am shooting for. I just want to get the bevel started in the foam. Using the groove from the stringer as my guide.

Ok, so now that I have my bevel started, I use that to guide my sanding block and finish the bevel out to the rail.
Go slow and be smooth. I try to keep my sanding block from “rocking” as I’m sanding. I want smooth, straight, flat passes.
Notice again how I am not touching the bottom 1/4" of the foam… So, you can see about 1/4" of flat verticle foam at the bottom.

Once I have one half of the swallow tail beveled how I like it, I do the other side to match. Using the hard sanding block.

Last, I use a piece of screen to round over that edge that is 1/4" up from the bottom of the foam.
Grab the screen with 2 hands and pull it along the edge like you were smoothing a rail band.
In the past, I have skipped this step and left the tail angular… That looks cool too.

very nice Crisp. What’s up with that greenish foam?

thanks Greg
It’s USBlanks colored foam…
It’s supposed to be grey. Looks purple in person. Green in photos…
Wonder what it will look like glassed?

pretty sure it will be brown.


It’s not glassed yet??!!!

Looking Good Chris. Bashams in San Clemente has lots of Surform tools like the one Chris posted. Rumor has it they are open on Sat and Sun now…Rock on!

“It’s not glassed yet??!!!”

Hopefully it’ll get glassed this week.

Very good way to go about it crisp. Your technique is a step by step process that is easily repeatable. To develop as a shaper and to get consistent results from board to board a shaper must develop techniques that are repeatable at every Blank in order to insure consistentcy You have developed a technique that achieves that. I lean toward simplicity myself. Complicated formulas for rail bands and concaves are not my thing. I use the same “process” every Blank from start to finish. I’ve seen very good shapers cut but cracks in with everything from grinders to hack saw blades. Cutting the stringer to the exact middle and leaving the vertical edge at the bottom are key to good results. Nice process. Very well thought out. Lowel

I think you just changed the way I do them. Nice. Mike

Yup my neighbors work the shop on weekends 11-2 I think?

“To develop as a shaper and to get consistent results from board to board a shaper must develop techniques that are repeatable at every Blank in order to insure consistentcy”

I thought that’s what computers were for? If reproducing shapes, my money is on the machine for consistency.

But the truth is that if every rail, concave or swallowtail looks differant from the last board you did, you’re still just a “hack” who can’t do the same thing the same way twice. I’'Ve yet to see a “machine” put in a finished swallowtail.

Rock on? I prefer to keep it jazzed.

“Cutting the stringer to the exact middle and leaving the vertical edge at the bottom are key to good results.”

Thanks for the kind words everybody.

I reread my original post and realized that I failed to mention the first part of the sentence from McDing quoted above…
When I do my first cut with the saw, I am very careful to make a clean straight cut the FIRST time.
When I get to the stringer, I am VERY careful to cut only to the center of the stringer.
The best way I’ve found to do this is to check the topside of the stringer and the bottom side of the stringer as I go.
Then when I cut with the saw from the other side, I do the same and meet the first cut right in the middle of the stringer.
This gives me the beginnings of my “groove”.
This makes the next step with the rasp SO much easier and less likely to slip out and gouge the foam.

Hope this all helps someone