# for Bill Barnfield : shaping longboard rail bands .....

hi Bill !

as you asked me to do, "when [I am] ready to do this , please post " …

Thanks , I am ready to absorb / see [hopefully!] this information !

[I will be out at "Hicksy’'s on [our] friday…[your] thursday , I believe ].

cheers !

ben

[=Blue]Aloha Ben

I will shoot you an answer this evening. I gotta get home now and catch the season opener of LOST!

Ok Ben, here ya go. Its a long one so tough up!

In my world, cutting rail bands have 3 purposes.

1. To transfer the bottom curve into the deck curve, harmonizing everything in between while controlling precision and symmetry.

2. To create the actual profile or shape of the rail.

3. To create the volume of the rail and ultimately the whole board.

Creating the actual rail shape is fairly obvious and while it is super important there is a way to do it that will blend all the various aspects of the boards design in the process.

I build my boards from the bottom up. But I visualize my boards as a wire frame floating in space were I can see each line and how it relates to the next line as the whole shape blossoms into full view.

If we take a templated, blank in its most primitive form it consists of the deck, bottom and rails, which are nothing more than the vertical surfaces that are the outline at this point. Lets imagine that this blank has the same 3” thickness throughout, in other words, no foil to it.

As a base starting point I use the rocker line down the bottom stringer line of the board. To keep it simple, lets start with a flat bottom rail to rail even though any bottom shape is possible. With a flat bottom, the rocker along the stringer is the same rocker as it is along the rail. If we cut a 45 degree rail band on the bottom and we make that band exactly the same width from nose to tail, then the bottom rocker will be evident in the upper edge of that rail band where it intersects the outlines vertical, just like it was evident in the bottom/template junction. Do you see the connection?

Now lets make it more realistic but more complicated. Imagine the board with a Vee Bottom. If the board has the same amount of Vee, say a 1/4” from stringer to rail and nose to tail, then in a sense, one half of the boards bottom is really a wide band cut on a very shallow angle. If we cut the same bottom edge rail band, then the upper edge of that rail band will still reflect the actual bottom curve at the stringer, twice removed.

If the Vee is not consistent throughout the bottom it will complicate things further. If the Vee is 1/4” only in front of the fins, then fading to zero at the tail and the nose, the stringer rocker won’t be exactly duplicated out at the template. The rocker line at the template will be altered relative to the Vee panel.

Of course, the rail band at the bottom edge of the template needs to be a tapered band to create the rail edge and thickness foil of the board. Since that tapered band is narrower at the nose and tail, it also transmits a slightly different rocker curve from its bottom side to its top side. But the top side though progressively changing is still a reflection of the original centerline rocker and that is the key.

The widest part of this lower rail band will be 1/2” to 3/4” depending on how big you want the radius or ball bearing of the rail to be. The secondary band you cut on the lower side of this band will regulate how far under the tucked edge will be.

Now when you flip the blank over, deck up, and look at it from an upper side view, the top side of the bottom rail band will give you an accurate idea of what the bottom rocker is like, even though you can’t really see that stringers rocker curve anymore.

Remember that our blank is 3” thick. So at the nose and tail we will be getting almost 3” measured from the top of the bottom rail band. But in what will be thickest point of the board, the measurement from the top of the rail band to the deck will be more like 2.5” or less.

To cut the initial top rail band, you have to be able to visualize that wire frame view I mentioned so you can see where this bands lower edge should be relative to the thickness of the finished boards rail. Between the lower side of the top band and the upper side of the lower band will be the remaining vertical surface of the Template. This is now also a band. And this vertical band also needs to be tapered. The way this taper happens is by how far you cut down the lower edge of the upper rail band and the secondary band that will be cut right on top of the junction of the template band and the upper bands lower edge. Don’t make the vertical band too narrow or the rail will be too thin. Remember you can’t add back foam and the only way to save it will be to make the template narrower to thicken the rail back up.

Imagine again that wire frame. Don’t cut the upper band too far down or the rail will be too thin or tapered. Remember that you will be cutting a secondary band and you have to leave enough material there to cut this band and round out the rail without making it too thin.

The taper of the template band is crucial to the thickness flow and foil of the rail. It takes experience to know how far to go and where to stop. Additionally, since you are matching the lower edge of the upper band to the top edge of the lower band with the template band caught in between, you can see that the lower edge of the upper band will collect the stringer lines rocker from the lower bands top edge and the top edge of the upper band should, as we have discussed, be a continuing progressive reflection of the bottoms stringer rocker as it has wrapped all around the board.

But at the deck, there is a problem with this and that is the regularity of the thickness of the deck of the blank and how that upper band’s edge interacts with it. Since the deck of blanks are rarely exactly what one might want, then the deck needs to be shaped down and the regulator in doing that is the primary deck rail band’s lower edge. Typically the upper edge of the band will warble all over the place depending on the thickness of the deck. Because of this you need to keep an eye on the lower edge of the deck band as you cut the deck down toward it, creating a nicely tapered band with clean arcs on both upper and lower sides.

Assuming all other bands have been cut and tapered properly this top edge will now reflect the bottom rocker and as such its arc can be matched up to the deck stringer line to create a deck arc that nicely matches the bottom curve.

While I have discussed mostly the primary bands, there are also secondary bands that go on the junctions of each of these primary bands. These bands are really no different accept that they are much narrower and taper out much finer at the ends. Keep adding bands on top of bands till the rail is smoothly blended into the deck and bottom.

In summary:

Visualize well, the finished board you want to make.

Plot your rail bands to match your vision, use a wire frame view to isolate the lines.

Utilize the edges of the bands to transfer the bottom rocker around to the deck

Use the width, depth and taper of your bands to regulate the volume and shape of your rails

Maintain clean consistent arcs in the edges of your bands to eliminate bumps and dips and ensure symmetry

Have good lighting in your room to pop the shadows and highlights so that your bands are highly visible.

[=Blue]Aloha Ben

Here is the photo you asked for in your PM to me.

These are rough cuts that I did quickly so I could post the photo and give you a general idea of what bands do. This board is 7’6" x 18". The blank is on the thick side and I did shallow cuts so I could go back later and do the exact cuts and bands and not run out of material.

Depending on how wide and deep you cut each band it will determine the volume and shape of the rail

Depending on how you taper each band it will effect the overall foil or thickness flow of the board.

Note how the Primary deck band will have to be cut deeper to bring the secondary bands taper down narrower in the tail to thin it. Then the actual deck thickness will also have to be cut down to bring the primary bands taper down narrower in the tail. All to create a thin tail

Many shapers would do the bottom. Then switch to the deck thickness. Then do the rails.

That isn’t my process. As I said before, I start at the bottom and work my way around using the bands to create the thickness of the board. That excess material on the deck is the last thing I remove with the planer.

I don’t use a sureform. I go straight to 60 grit sandpaper and a balsa sanding block. Then 150 grit.

Good Luck

Mahalo Bill

That’s a good photo and post…

Is there some science on how deep into the deck the primary band goes…

I think I was told the markings are 2" then 4" off the rail line but that’s probably mumbo jumbo from the JC video…

also I assume not but does the angle of attack from the planer in relation to the flat surface stay constant through the whole band or does it rotate as you walk tail to nose and nose to tail?

I never uderstood how you get a nice clean line if you are basically doing the light heavy light approach (again like JC shows) in manipulating your planer as you take off material versus just setting it down and letting it ride flat against the blank the whole pass.

Sorry for the newbie questions …

Aloha Oneula

Quote:
Is there some science on how deep into the deck the primary band goes..

No there is no science, just ART! There is no specific measurement system that will work all the time. And it isn’t good to get adapted to such systems as they don’t allow the flexibility necessary to be a great adaptive shaper.

In my system, the primary deck band is not a singular thing that you just plop on the deck. The primary deck bands lower edge is established by the bottom deck bands upper edge. I know it is hard to grasp this because most shapers shape the bottom and then shape the deck down to it. Those are 2 distinctive and separate steps. I don’t work that way.

In my system, the deck band it just another band that comes after the bottom band, but it just happens to be on the other side of the board. So in a sense I am not shaping the deck when I do the deck band, I am just doing another secondary band off of the primary bottom rail band. Imagine if you were shaping a round or slightly over bullit shaped item. All the bands would just roll together. There really wouldn’t be a deck or bottom.

Visualize this. A surfboard is like a 50 caliber bullit that is squished a bit flat on 2 sides and then bent in a bit of an arc. In shaping, I see the board as a complete form like this that I am just oozing around to meet the shape I have in my mind. I call them deck or bottom bands, but they are really just systematic guts into the foam block that I need to make to create the eventual form I am trying to create.

I don’t measure any thing other than the thickness of the blank before I shape the bottom and afterwards to make sure I have enough foam. I don’t measure the width of the bands or their locations. Each of my bands are a reflection of the previous band. Without the previous band there is no need for the next band. And I don’t know where or how the next band will emerge until I have the previous band finished. I simply roll the bottom into the deck using the bands as the incremental steps.

Quote:
I assume not but does the angle of attack from the planer in relation to the flat surface stay constant through the whole band or does it rotate as you walk tail to nose and nose to tail?

The angle of the all my bands remains the same. I don’t twist or rotate them, if that is what you mean. The depth of the cut and the width of the band changes but not the angle.

Quote:
I never uderstood how you get a nice clean line if you are basically doing the light heavy light approach (again like JC shows) in manipulating your planer as you take off material versus just setting it down and letting it ride flat against the blank the whole pass.

John and I are good friends, but I have never seen his shaping videos, so I am not sure what you are referring to. John used to shape here at ProGlass but I never paid that much specific attention to his system or if that is even what is on the videos.

A lot of shapers use pressure and motor speed changes when they shape. I don’t. Regarding pressure, the planer is heavy enough. In fact, too heavy. Here is how I relate to it. I imagine the planer being attached to the ceiling by a sky hook and that I am just pushing it forward and back. The weight of the planer is, of course, actually being held up by my arms and the blank. But like a sky hook was supporting it, I just let the planer skim over the blank with the same pressure at all points.

I don’t allow a lot of weight to press on to the blank. The blank flexes and you will get rack dips where the racks support the blank and it can’t flex away from the planer. I allow only enough pressure to keep the planer attached to the foam and not press undue flex into the blank.

That “light heavy” thing sounds sketchy. I regulate the depth of the cut by continually adjusting the cut depth, no pushing more or less. I set the planer down, like you mentioned and just make the whole pass, adjusting the cut depth as I go. Some times I will make partial passes if I need more depth in an area.

Regarding motor speed, I run my planer fully on. I don’t “trigger” it to slow it down. A planers cut can’t be regulated by the motor speed like a sander or grinder can. If the planer blades are spinning slower they will just not cut very well, but the depth will remain the same.

You Just Click And Drag On The DSD Program.

[=Blue]HA HA HA…LOL

Good one Sunsetpoint!! Mike Croteau and I are on the floor laughing!

that was a good one sunsetpoint… and probably more realistic than anyone imagines too!

We still need to set up that meeting maybe this weekend? PM me if it’s okay I’ll bring some of my faves…

Yeah sorry Bill.

the light heavy light was my interpretation of JC’s direction to use your planer like an airplane landing and takng off real quick. So you come in take your cut and then get off the foam… Seems kind of a jerky method when you’re trying to do bands…

I’m trying to under stand band cuts which I’m terrible at cause I’m trying to translate the cuts into hotwire jigs that I can run against the rail to slice off long strips of foam to form bands versus grinding or cutting off foam with a planer. Using a hot wire on a block run across the rail will be real alien compare to using a planer. But definitely less noisy and messy for my situation.

My choices are a straight wire held at an angle to the deck and bottom or curving a stiff wire to a desired curve like the curl of your hand and running that along the sides to form the rail.

There’s alot of negatives to both if I don’t understand the basics of whats going on blending deck to bottom and building in the appropriate profile and release…

It just seems that the angle of the band gets steeper as you enter the tail to get the almost vertical sharp edge you want and then flattens out way up front as you round out the edges to a more 50/50 relationship near the nose.

sorry for all the silly questions I’m sure all the experienced shapers are laughing…

But I’ll admit I don’t know what I’m doing as far as shaping boards…

The change in tools is what has me mostly confused…

But it’s the way I’m gonna go…

Your explanations are a great help.

thanks again

Bill- Please say Hello to Mike for me, I hope he is doing well. -Carl

Aloha Oneula

I have great respect for Carper but doing touch and go landings with the planer like an airplane doesn’t make sense to me. The cut is regulated by the adjustment of the forward shoe. I can slide my planer all over the board and take off zero material if I zero out the shoe. I don’t know why one would need to take the planer off the board to end a cut or stop cutting. On my last really fine cuts near the tip of the nose and tail, I do lighten up the planer more or just continue off into space past the board, just to make sure it doesn’t catch an edge or something and cut deeper then intended or gouge the foam. Because at that point I have no room to correct for that kind of error as the board is power planed out to the point were it is almost glassable. Maybe that is what Carper was referring to.

Normally though on most of the bands, at the end of the board, I simple spin my planer around and head back the other way. Sometimes I don’t even spin it I just go back in reverse. All the cuts are regulated by my depth adjustment on the planer and the amount of passes.

Hotwiring Bands:

I don’t think you can realistically cut bands with a hot wire. Imagine this. The rail is like half of a cylinder. But you are trying to create the cylinder out of a square block. To do so you need to cut several 45 degree bands on each corner. The smaller 45s on all those new edges from the first cuts. Continue until you have the cylinder shape you want. All those 45 degree (or so) cuts are what we call bands in shaping.

Now, imagine an 8’ long 3" x 3" square piece of foam that needs to become a cylinder by cutting off the square corners in bands, till it gets round down its whole length. Doesn’t sound too hard really, but…

Now imagine that cylinder, you are just getting comfortable with creating, needing to be tapered at the ends. That is, smaller diameters at each end and fatter in the middle. Imagine how those bands must be progressively increased to create the smaller diameters at the end.

Ok, you just got a handle on that… Now imagine that your cylinder needs to have a long arc in it that spirals up at one end more than the other! Yikes!! Now you can see how complicated the bands really are.

To do this with some kind of jig controlling the hot wire is going to be way too complicated. The CNC hot wire cutters can do this but I don’t think you are going to be able to incorporate all the required variables to do it by hand.

Oneula, my shaping schedule is always unpredictable and erractic but your welcome to watch any time. Just stop in and check. If I am not tied up I can show you some stuff even if I am not shaping at that moment.

Quote:
Bill- Please say Hello to Mike for me, I hope he is doing well. -Carl

Aloha Carl

I will tell him. He just had knee surgery and they are talking about doing something to his heart. It is strong etc, just has an irregular beat.

Otherwise, he is big, strong and just as spntaneous as ever. Just a bit mellower as he ages.

I am sure he will appreciate your concern.

From my understanding having watched JC videos is that JC is talking about the ANGLE of the planer blades in relation to the blank itself when making rail bands…

“opening up the planer” means bringing the planer perpendicular to the rail band, so that the entire width of the blade is cutting material… a long straight flat cut of rectangular shape…

going to the other extreme, moving the planer sideways, where a cylindrical groove would form in the foam… ie cutting less material away…

so in between you could manage the width of the actual cut (depth staying the same) and you the rail band is thinner up in the nose and tail, compared to the middle of the rail band…

So to carve the rail band, would just be a matter of rotating the planer so the blades make a wider or thinner cut …

hope that makes sense to someone because the more i type the less it makes sense!!

Cheers

Ant.

Oneula, I think you could make a hotwire bent into your max. radius for the middle of the board, and extend the frame so it runs along the deck side.

Say, if your boards are 2.75" thick at the middle, and you dome the deck a bit, you can make a 2.5" diameter half-circle wire. If you hold it to the deck side, you’ll get a 50/50 rail where the board is thickest and the wire will just hang down off the bottom where the board is thinner. So, everywhere the board is 1.25" thick or less, you’ll get a downrail with a bottom edge. If you want that, leave it, like for tails. If you want to ease that edge off, its just EPS, a couple swipes with a sanding block & you’ve got a smaller 50/50, or an egg, or a chine, or anything you like…

First of all a sincere thanks Bill

your openess to share your technical/artistic knowledge in simple terms here is unsurpassed…

Thanks for the offer maybe one day…

Mahalo again…

And thanks Benny

I was getting discouraged after understanding what Bill was trying to get across because I really am not planning on using either a planer/belt sander or big block with 50 grit to shape my boards any more because it truly does pollute my neighborhood with little white foam bubbles shaping in the front yard. Since this is a part time hobby I also don’t want to construct or setup facilities just to support it cause there are definitely many other things more important to worry about and people who actually do this for a living that could use the what ever hard cash I’m throwing away “playing around”. I always believe you should always support the “starving artists” out their pursuing their dreams if that is not yours…

But I can envision what you are saying and I think that’ll work fine.

At first I thought I would have to build different tools with different curve profiles for every 1 foot of board rail and then some how blend them all in but your method makes a lot of sense and I’ll give that a try first…

And sorry Chip for hijacking…

Hopefully some of what Bill just laid out here will be a benefit in your new project… I know it was a big help to me in understanding how the pro’s look at the process of rail banding or liek BIll saiding “bringing the bottom to the top”.

I like that.

Quote:

Oneula, I think you could make a hotwire bent into your max. radius for the middle of the board, and extend the frame so it runs along the deck side.

Say, if your boards are 2.75" thick at the middle, and you dome the deck a bit, you can make a 2.5" diameter half-circle wire. If you hold it to the deck side, you’ll get a 50/50 rail where the board is thickest and the wire will just hang down off the bottom where the board is thinner. So, everywhere the board is 1.25" thick or less, you’ll get a downrail with a bottom edge. If you want that, leave it, like for tails. If you want to ease that edge off, its just EPS, a couple swipes with a sanding block & you’ve got a smaller 50/50, or an egg, or a chine, or anything you like…

From where I stand, the whole concept of rail bands is to keep a reference point from where you start, to where you end at your desired intent. Bennt1, w/ due respect, your comment suggests that it’s no big deal to change symmetry and/or thickness flow along the way because it’s no big deal. This might be a fundamentally unsound way to learn, or teach. Learn to use the planner

correctly

Quote:

And thanks Benny

I was getting discouraged after understanding what Bill was trying to get across because I really am not planning on using either a planer/belt sander or big block with 50 grit to shape my boards any more because it truly does pollute my neighborhood with little white foam bubbles shaping in the front yard. Since this is a part time hobby I also don’t want to construct or setup facilities just to support it cause there are definitely many other things more important to worry about and people who actually do this for a living that could use the what ever hard cash I’m throwing away “playing around”. I always believe you should always support the “starving artists” out their pursuing their dreams if that is not yours…

But I can envision what you are saying and I think that’ll work fine.

At first I thought I would have to build different tools with different curve profiles for every 1 foot of board rail and then some how blend them all in but your method makes a lot of sense and I’ll give that a try first…

And sorry Chip for hijacking…

Hopefully some of what Bill just laid out here will be a benefit in your new project… I know it was a big help to me in understanding how the pro’s look at the process of rail banding or liek BIll saiding “bringing the bottom to the top”.

I like that.

Man, I love the Barnfield threads! Thanks for giving away so freely.

I too have had the privilege of watching some truly great shapers work in fundamentally sound practice. Again, w/ respect Oneula, most of you carport guys are way too good to not be using a room w/ sidelights, independently switched or plugged in, or use a planner. All the talk of fancy, expensive sanders etc. comes down to the basics. If you ever get a chance to see a room w/ proper lighting, or a shaper who can plane right down to the finished board, it will change your whole way of thinking. Try taking one of your carport boards that you think is finished over to some shapers room and put it to the sidelight test. I cringe to think someone might shape extruded, or styro w/ a belt sander or other inaccurate tools.

Oneula, sounds like you’ve made some rail-banding hotwire tools of your own, but here’s what I did for the eps board I’m currently building. The tool I made worked fairly well, but needs some minor adjustments. My next tool will look more like the one in the picture, my first one was bulkier and harder to get the correct angles with. I’m sure after my changes it will work much better on the next board. Because you rest the guide against the rail and the BOTTOM of the board, the hotwire follows the rocker curve rather than the deck foil. You set the tool for the thickest portion of your board, and the cut gradually fades out as you go toward the nose and tail.

I doubt I’m the first person to try this, any comments or suggestions from the more experienced?

Oneula, I wouldn’t give up on the rail banding tool idea. When I was cutting out my last blanks I found that with a little extra work I could easily shave off 1 mil high spots on the blank. It might take a few trys to get it dialed in.