Bill Thrailkill, glass on method?

Can you explain your method for glassing on fins please?

Kind of board?      Size of fin, or fins?       Fin material?         Tell me about the board you are building, if you don’t mind.

HP Twinzer.

6’0" x 20 1/2 x 2 1/2.

Bamboo fins made from a panel that I made from 8 layers of veneer.

Main fins will be 5 3/4" tall x 4 3/4" base… Canards will be 3 1/2" tall x 3" base.

Going with Griffin’s template for the mains… I am not sure yet for the canards. I will probably draw something up.

Using the 6’2"A USBlank in Red.

Plan to glass it 4+4 deck and 4 bottom with a fin patch…

What else would you like to know?

In the “day”

We had real fiberglass rope.

I know Stingray has some

Just saw on EZ foam what looks to be “rope”

http://www.foamez.com/fin-rope-3-fins-p-223.html

not the heavy cloth I’m pickin’ strands out of now.

In the bygone days you seriously had to soak and work the rope for a good clear no bubble job.

Not so hard now a days.

a good roper doper is a classic

old or new school.

My apologies Bill!

But as soon as I saw this I thought of the old school way!

At least I waited for your reply.

In the “Day” of no breaky, crap!

Man, we could stand on the deck (on the lawn)

Ha! 

Try that today.

Eh Bill?

Remember?

Peter Cole doing the “Hot Dogger” scene

runnin’ up and down a board on “da” lawn and gyrating moves on one Bud Brown old surf flicks?

Best.

P.S. You’re in good hands Chrisp…

Right on Matt!

I’ve heard/read rumors of a no-rope (iirc) glass on method.

Swied mentioned that he used Bill T’s method on his Nug build.

Really interested to get the scoop from Bill himself…

 

I am also intrigued by a method that Greg Griffin mentioned where he routed slots in the bottom and set the fins in that before glassing 'em on.

GDaddy did it on his SBC board iirc.

 

More than one way to skin a cat as they say.

I’m REALLY interested in NOT doing the big fillet or whatever it’s called at the base of the fin while still doing glass-ons.

Chris, note that Jobson would have his canards routed in back when he was doing glass ons. Like GG, he didn’t like the fillet. 

I’m sure Gdaddy would be willing to share how he does his. 

Curious: why glass ons?

 

As a matter of curiosity, how thick are you making your fins?     Also, are you putting a few layers of glass on the fins, before actually mounting them on the board.     

Bill,

The panel is just shy of 3/16" thick right now. Bamboo only…

So, I can glass them before putting them on the board with as many layers as necessary.

 

 

Ghostshaper,

I am just kinda feeling the glass ons for this one.

I really like this board:

http://forum.surfermag.com/forum/ubbthreads.php?ubb=showflat&Number=2044173&site_id=1#import

 

Not married to that idea though. I have some more Gearboxes I could use and I could foil some fins from a piece of G10 I have.

Also, I’ve been mind-building bamboo fins for the Gearboxes for a while now. I could try that too…

I read how you like your 4WFS for being able to adjust cant and placement on your Twinzers.

I’m sure you’ve read GG’s method for adjusting cant in a non 4WFS box.

So the gearboxes should work. I might need to mold a base for the canards though to get the cant that I need.

Anyway, just thinking out loud. I still need to shape the board hahaha

I think I am going to shoot for doing a channel like Oak Foils does on his Twinzers:

http://forum.surfermag.com/forum/ubbthreads.php?ubb=showflat&Number=2231292&site_id=1#import

That looks more manageable than the Hoyte channels.

 

PM sent.      We need to talk.

Cant in your canards is going to be difficult, if you’re trying to get 11°. BC my c5 boxes have blown up, I’ve tried different cants in the canards, and I’ve found that I can’t feel the difference. I think the cant in the mains are far more important. Wil uses 4°, I’m running 2° in mine, after 4 felt too slidey.

As far as channels go, the hoytes in your link look reversed of what I’ve seen. Wil told me it’s there to create low pressure, so the channel needs to widen as it exits.

Looking forward to your build

Right on Ghost!

WOW, I would not have guessed such low cant for the mains!

Glad you mentioned that.

I was going to go with 6* and I figured that might be too low a number.

IMO doing all glass ons for your first twinzer is just… well being a glutton for punishment.  Hope you enjoy hand sanding, Chris.  You should at least use boxes for the main fins, then glassing and sanding the canards will be easy.  and they are small enough that they don’t need that much glass to hold them on (they don’t take much load). 

Thanks Keith… That sounds like a good idea.

Ghostshaper’s last post had me rethinking all glass ons…

I may use my last Proboxes on the mains so that I can adjust cant but still glass on the canards like you say Keith.

Nah, do it the hard way first chrisp.  It’s not THAT hard.  Little rat tail file, rolled up pieces of coarse paper, couple a beers.  Mike

Right on Mike…

I did glass on runners on a bonzer 5 before Mike but I am having doubts on cant numbers for this board…

Going with Probox would allow me to adjust that.

hmmm

Still interested in learning Bill method.

Bill never wrote it down for me.  He just described it to me verbally about  six years ago.  The process that he described was quite detailed and specific to larger single fin boards.  I don’t remember the specifics but I have used the general conepts to create a system of my own.

My latest application of this theory was with a five fin setsup.  The basic concept is that one layer of glass has the weave running vertical/horizontal.  The next layer is cut with the weave rotated 45 degrees.  The next is vert/horiz, and so on.  This alternating orientation of the weave provides maximum strength.  Another thing to think about is that you will need more layers of glass at the point where the fin intersects the board than at the tip of the fin.  The first few layers of glass that you apply should be short little rectangles.  Next apply some layers that go about 1/4 of the way up the fin.  Next go 1/2 way up.  After that apply the layers that cover the whole fin.  At the very end I apply another small rectangular piece at the base.  This what I call my sacrificial layer.  It always get burned off in the sanding process, but then the other layers remain perfect.

When applying this many layers of glass it is easy to introduce bubbles which will cause the lamination to appear cloudy.  Here is the process that I learned through trial and error (mostly error).  

  1. I cut out all of my strips of glass ahead of time and place them close to the work area.
  2. Next I will mix the epoxy and brush the fins to get them wet
  3. Then apply the small strips two at a time to the wet fins (both sides).  I smooth out the fabric with the brush or my fingers an make sure that it wets out completely.
  4. Before applying the next layer I dip the brush in the bucket and give the surface another light brushing.  Note: Always apply dry glass to a wet fin.  Never do wet glass on a dry surface.  That's how bubbles form.
  5. Keep doing the same process untill all of the layers have been applied.
  6. At the very end I will use my fingers to lighly smooth out the angled surface where the fin meets the board. Try to make this a nice crisp corner.  I also draw two finger across the outer edge of the fin to ensure that the edges are fully saturated with resin.  Beyond this edge you should have dry fabric since it was applied dry to the wet surface.

That’s pretty much it.

Note: In the above photo you can see the “sacrificial layer” at the base of the closest fin.

Those are some very nice looking fins.