New Traveler - WOW!

[Noah]

KEN:
All I was refering to was the photo and info explaining how the C34 traveller is built. There is a bronze threaded plate that the track screws bite into then go into empty air space on riser pedestal. The two end bolts should be 9-1/2 in through bolts fastened with acorn nuts on cabin ceiling. Butyl tape on heads with Tifgel on threads is good approach to assembling the works.

[KWKloeber]

Noah

Ok, so there's no screws into fiberglass.  Forget all I said about epoxy sealing "into-fasteners".  It first sounded like "screws" were being cut into the fiberglass riser.

I have a similar issue to take care of on the J/120 traveler.

Is the bottom of the track flat, or is there a recess the length of it?

kk

[Noah]

Ken: If you go to that previous link I gave you there are pics.

[KWKloeber]

Yes I know --  but I can't tell if the bottom of the track is "flat" or if there is a recess (above the plate that's pulled off the riser that's still attached to the track.)

[Noah]

i assume is is same as top with a small extruded groove, but I will look at my boat tomorrow where my 3 bullet fairleads bolt on underneath.

[KWKloeber]

Noah

Ok, if there's just the "slight" groove (as on the top,) it's not an issue. 

Here's what I would do IIWMT.   Yah need a receptacle where the butyl gets pushed into, under force of tightening. It needs a shape that compresses the butyl against the surfaces past which water could leak.

Since Russ can't countersink the risers, he should countersink the holes on the bottom of the traveler bar.  That creates a reservoir where under compression (tightening the bolts) butyl gets forced against the bolt, and against the top of and the holes into, the risers.  A little will ooze out and seal under the traveler bar.

THEORETICALLY, sealing that way, there is no need to put butyl under the recessed flat head bolts.  But, as belt/suspenders, IIWMT I would also want a similar good seal on the top of the traveler bar. 

Russ is correct in his concern that the face of the flathead bolt will basically force "all" the butyl out, since the angle of the countersink and the angle of the bolt head are the same.

So, I would drill a slight (1/4" deep?) recess into the bottom of the countersink for each bolt head, so that under compression butyl wrapped under the bolt head will get forced down into the recess, and against the bar and against the threads.  If the recess could be angled (a small diameter countersink) that's best, but simply a drill larger than the bolt hole will work as well.  If they're 3/8 bolts, I'd use a 9/16 bit to make a recess for the butyl.

Exaggerated but, from the side it would look like this, with the "squared off" reservoir for the butyl being at the bottom of the countersink"
__   _________   _____
     \\     bolt    //
       \\  head  //    traveler bar     
        |\        /|
        |_|    |_| <---- recess
           |    |
           |    |

kk

[Stu Jackson]

WADR, this is gettin' too complicated.  I put two layers of butyl tape underneath both the length and the "ends" of the width inboard and outboard, did the Maine Sail bolt head "wrap" even on the ones I had to turn.  That was a few months ago, been some rain since, no leaks.  Just be careful how you apply the butyl, and forget the "theoretical" (but important) "issues."  If you use enough butyl and understand that even if you have to turn the bolt heads a bit there WILL STILL BE butyl filling the slight gaps, especially if you push down hard before you turn anything.  As I noted earlier this is part of regular maintenance. Even if it is once A DECADE!!!

[Noah]

 

[Noah]

Ken- FYI- I refreshed my memory and looked today at my traveller travk and the bottom of the track is absolutely NOT flat. It has an approx 1/2 in wide by 1/4 in groove/channel up the middle the entire length. Still should be able to bed the outsides where it meets the fiberglass riser/tower with butyl tape.

[KWKloeber]

Noah

That shape seems to be somewhat typical.  I bed the J/120 Genoa tracks (which had the same "groove") with a heavy butyl goop ring around each fastener.  We wanted dirt/gunk behind each track to flush underneath, rather than get trapped (if thr tracks were sealed the whole length.) 

The traveler is a different situation, being atop the funky embedded plates.  However, IIWBT I would bed it with a 2x (3x if necessary) layer of butyl in the groove area only, rather than under the entire width of the track.

ken

[Stu Jackson]

>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>

The traveler is a different situation, being atop the funky embedded plates.  However, IIWBT I would bed it with a 2x (3x if necessary) layer of butyl in the groove area only, rather than under the entire width of the track.

The track underneath is for the inserts for the fairleads.  You can't see this from the side of the track outside because of the end cap.

I disagree about bedding this way.  I see no reason for anything underneath to "breathe" and preferred to try to eliminate anything getting under the track at all if I could help it.  I did the sides and the ends.  Perhaps a four-layer of butyl in the track underneath would, might, could help.  Dunno.  I'll see if it leaks in five years.  The hole for the dorade/cowl vent is right there, and as I reported earlier, that's where I first saw the leak in 2005.  Hmm, that was quite some time ago...

Only reason I rebedded THIS time was because of another leak, traced finally down (up?!?) to the cowl vent, just the opposite of last time.  And that traveler bed in 2005 was done with silicone, which was still holding.  Butyl's simply better than silicone.

Your boat, your choice. 

We're dancing on the head of a pin here, again.   

[KWKloeber]

Stu, to answer your email ... and et al, to clarify why/what I intended re: filling (ONLY) the "groove" portion of the track, see my sketches.

(A)  The track and riser, in section view. 
Excuse that they are NOT to scale NOR precise. I don't have the dimensions, except that Noah estimated the recess was about 1/4".  The "rest is a guess."

(B)  If one lays strips of butyl above the risers as shown.....
What happens when the track is bolted down and under compression?

(C)  The butyl strips underneath the track edges act AGAINST you tightening down the track. 
You don't want a gap there, you ideally want the track bolted down as tightly to the risers as you can get it.  So the butyl tape there gets squeezed down (to 1/64" thick -- OR LESS) and out -- and it does not create a permanent, lasting seal. 

Under the track proper, around the bolts, around the holes thru the top of the riser -- there's no butyl under compression.  The 1/16" thick butyl tape doesn't begin to fill the 1/4" recess in the track.  There's a huge gaposis. 

(D) IDEALLY, create recesses for the butyl.
(YBYC, but IIWMT) I'd countersink each fastener hole in the bottom of the traveler bar.  And SLIGHTLY countersink each hole into the fiberglass riser.  (SLIGHTLY because you don't want to "open up" the embedded plates.)

Fill ONLY the RECESS (avoiding the edges of the track.)  Use as many layers as necessary to SLIGHTLY overfill the depth.  There's no need/point/benefit to put layers of butyl under the protruding edges of the track.   So when the track is bolted down, what happens now?

(D)  ALL the butyl under the track goes into compression.
It forces itself into the recessed (countersinks) you placed into the track and into the top of the riser.  The butyl under compression makes a tight, more permanent seal, and butyl "plugs" are created around each fastener and hole.  Whatever leftover butyl there is from SLIGHTLY overfilling the recess, squeezes out, but the rest remains under compression.  What oozes out isn't necessary to make a seal, and NOT putting it there beforehand, eliminates a layer of goop that acts AGAINST you bolting down the track as tightly as you can to the riser.


Onto the top of the track.

(F)  The bolt head countersinks in the top of the track (excuse the artistry.) 
If you put butyl around the flathead bolt, "ALL" is squeezed out and there's nothing but a VERY VERY THIN FILM between the angled faces. No permanent and lasting seal is created.

(G)  So create a recess for the butyl.
(YBYC but IIWMT) I'd drill out the bottom of each fastener countersink.  Just enough to form maybe a 1/4" recess.   

(H)  Then what happens when you bolt down the track? 
The butyl around and under each bolt head get compressed into the recess underneath the countersink.  A thick, totally under-compression, butyl "plug" is formed around the bolt, which seals the hole much better.

So, is this overkill, or is it right-kill to create a permanent, leak-proof seal? 
Your traveler, your decision!  YTYD - Hey yet another acronym.

The short story is, that it matters not only WHAT you use at home to seal around a window or a door -- or on your boat -- but is also matters HOW you place the sealer to do it the best and longest lasting way -- whether it's Lifeseal, butyl tape, or Dow 795.

Will it "work" to simply lay the track into butyl?  Ya, for a while.
Is it the right/best way to do it?  Na, it's designed to fail.
That's my story and ImStickinToit.   


cheers,
ken

[Noah]

Makes sense to me. When it comes time to rebed, I will follow your suggestions. Thx!

[J_Sail]

Ken,

Was that something along the lines of YBYC*?

* "Your Bed Your Choice"  ... Maybe better to not go there...


Your posts on bedding have been excellent. It's important for folks to understand that a paper-thin layer of bedding does very little good if there is any chance of even the slightest motion. Sealants rarely can handle thickness changes of over 50%. Given the thermal expansion/contraction over temperature extremes of sitting in direct sunlight and then cold nights, a paper-thin layer that gets squeezed to microscopic thickness when parts are expanded by heat, is unlikely to seal when things cool down. Modifying the interface to provide for a thicker layer of captive bedding is almost always a vast improvement.

[KWKloeber]

Exactly! 
I glad I'm glad you brought up the (for instance) 50% deal. I debated on that but nah, keep it simple.

k