Hobie Cat Forums

It is currently Wed Jul 30, 2014 8:41 am

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 20 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Tramp - how tight?
PostPosted: Wed Sep 14, 2005 5:43 am 
Offline
Site Rank - Deck Hand

Joined: Tue Aug 30, 2005 5:22 am
Posts: 15
Location: North Carolina
I purchased a new tramp for my '84 Hobie 16 five years ago. After finding this forum and reading most of the posts, I have now realized the importance of a tight tramp. My question is how tight? (At a recent regatta, I noticed most of the other Hobie 16's had their tramps tight enough to pull in the beam rails about 1" and the aft rail about 1/2". What I'm hearing is the tramp should be as tight as possible without tearing grommets.

Any thoughts?


Top
 Profile  
 
 Post subject:
PostPosted: Wed Sep 14, 2005 5:49 am 
Offline
Site Rank - Old Salt

Joined: Fri Jul 15, 2005 10:43 am
Posts: 779
Location: St. Louis, MO
Sounds like you are on the right track. A tight tramp removes any slop from the mating metal framework parts.

Just out of curioisty, are you saying you saw guys with thier tramps so tight that the midpoint of the beam rails were deflected 1" inward? I am a pretty good sized guy (250#) and I was not able to get the beam rails to deflect that much even when I stood on the tightened tramp while raising the mast.

_________________
Nick

Current Boat
In the market
Previous boats owned
'74 Pearson 30
'84 H16
'82 H18 Magnum
St. Louis, MO


Top
 Profile  
 
 Post subject:
PostPosted: Wed Sep 14, 2005 6:16 am 
Offline
Site Rank - Admiral

Joined: Sat Feb 07, 2004 8:28 am
Posts: 192
A tight tramp is beneficial for the general stiffness of the tramp frame. To get more tension in the lacing you could use the mainsheet system (should be triple block e.g. Harken, but old seaway might work too). Just loop a line (about 8 feet) around the tranp, attach the mainsheet blocks to the ends of this line and tension to a point where you pre bend the side rails (1.5 “). Tension your lacing as good as you can and than release the tension of the mainsheet. IMHO 1 " bend on the side rail is a lot (I would not aim for mare than that), front and rear X bar are much stiffer and might not bend much at all.

Patrick


Top
 Profile  
 
PostPosted: Wed Sep 14, 2005 11:50 am 
Offline
Site Rank - Old Salt

Joined: Wed Jun 30, 2004 6:39 am
Posts: 471
Location: Finger Lakes, NY
Tight is right, but a 1 inch bend seems a little over the top. I agree with Patrick. Tight without ripping out the grommets seems to be a good rule of thumb. Tight enough so that both hulls come the same distance off the ground equally when you lift only one side is perfect. The overall objective is to have both hulls operate as though they were one unit, not two, for best performance.

If your tramp doesn't have double-grommets, center and rear, I don't think you can get the tramp tight enough no matter how hard you try. (Bonus advantage of double grommets: criss-cross laces help keep sheets onboard because there is less space for them to escape through the tramp.)

A simple method of getting a tight “tramp” (besides cheap booze :twisted: ) is the tool on this page http://www.murrays.com/archive/34-35.pdf OR use two vise-grips*, sailing gloves, and a reasonably strong arm.
Instructions: First soak the line you are going to use. (The line stretches when wet and it will get wet when sailing-surprise!!). Have a beer. A friend can help so make sure he/she has a beer too. Now to the serious stuff-
>Attach line to frame (or pad-eye) and run DOWN through first grommet and UP through the second grommet.
>Pull the excess line by hand as snug as possible. Pull the line BACK TOWARD the first grommet. Pulling at an angle gives you leverage so don’t pull straight up out of the hole.
>Clamp one vise-grip onto the line as close to the top of the second grommet as possible. This keeps the excess line above the hole.
>The next step is almost one move: holding the vice grip clamped to the line, YANK the line tight (remember – at an angle towards the first grommet) and quickly clip the second vise-grip below the jaws of the first. This will lock the line tightly in place against the grommet. Actually shove the second vise-grip tightly below the jaws of the first vise-grip.
>Remove the first vise-grip, lace line through the next TWO grommets and repeat the procedure. You will always be working above the trampoline where your beer is. As you go along, friction and leverage work more and more in your favor to keep the line tight.

Hint: Have about 4 feet more line than you think you'll need. Cut off the excess when done

* If you are not “Tim the Tool Man” you might not know that there is only one true Vise Grip made by Irwin. This project goes best with a model 7R (flat square jaw) for yanking and a model 7CR (curved narrow jaw) to lock the line in place.

Have fun, drink responsibly, sail hard -
-Stephen

_________________
The fact that this windy world is largely covered in water obviously means that man was meant to sail.


Top
 Profile  
 
 Post subject:
PostPosted: Wed Sep 14, 2005 12:01 pm 
Offline
Site Rank - Old Salt

Joined: Fri Jul 15, 2005 10:43 am
Posts: 779
Location: St. Louis, MO
I like the vise grip idea. I don't know why I make things harder than they have to be. I usually use one of those "line grips" to get a good purchase on the lacing. While I hold it I have my fiancee thread it through the next set of grommits and I do a very quick switch to move to the next set of grommits. I am usually very tired after this and my hands are too worn to hold the beer.

See, you learn all kinds of important stuff on this forum

_________________
Nick

Current Boat
In the market
Previous boats owned
'74 Pearson 30
'84 H16
'82 H18 Magnum
St. Louis, MO


Top
 Profile  
 
 Post subject:
PostPosted: Wed Sep 14, 2005 1:04 pm 
Offline
Site Rank - Captain

Joined: Mon Aug 09, 2004 9:35 pm
Posts: 82
Location: Northern Texas
I really like the idea of the vise grips, but I found an easier and quicker method than the vise grips. Do everything that Stephen says, but instead of using vise grips take a wooden dowel that is the same size as the grommet. Taper one end, long gradual taper, so that it will fit into the grommet together with the rope.

Now start your tramp lacing however it needs to start. I have an 18 so my lacing actually starts at a grommet. I then take the lacing and run it up through the second hole. Now everyone has a tow vehicle. Go to your tow vehicle and pull out the lug wrench. If you don't have a tow vehicle, then use a bar of some kind about the same diameter as a lug wrench. I actually have a 3/8" ratchet that is about 10" long that I use. Take the lacing, wrap it around the lug wrench in a manner that it will not slip. Then take the lug wrench with the lacing and place it in your hand letting the lacing pass between your bird finger and your handcuff (ring) finger. Place one of your feet on the boat frame like you are trapped out to provide leverage and pull the lacing tight. Once you have pulled it tight, have your assistant push the dowel down into the grommet. Because we went up through the second hole, by placing the dowel down into the grommet if the rope tries to slip this will cause the dowel to pull even tighter. If you want the tramp really tight, then repeat the process from both sides. If not then just pass through two grommets so that you just have to pull from one side of the boat.

Just a word of caution though. If you have any weak areas in your frame, you are going to find them real quick. Also for you guys that might try this with a 17 or 18, I did this on a 1982 18 and found a deformed hull deck at the rear crossbar as a result. That is pretty dang tight. (Actually, there was a soft spot there that didn't become apparent until the tramp got tight.) Also, NO SHARP OBJECTS ALLOWED ON TRAMP is a sticker I am considering investing in.


Top
 Profile  
 
 Post subject:
PostPosted: Wed Sep 14, 2005 1:54 pm 
Offline
Site Rank - Deck Hand

Joined: Tue Aug 30, 2005 5:22 am
Posts: 15
Location: North Carolina
Thanks for the feedback everyone. I used my ratchet/strap system (the one I use to secure the boat to the trailer) to tighten the laces. At this point, my beam rails pulled in just under an inch and the hulls finally move in unison for the first time. I think I'll wet the line (as suggested) and see if the tension eases. If not, I may do it manually.


Top
 Profile  
 
 Post subject: Better than that...
PostPosted: Wed Sep 14, 2005 2:10 pm 
Offline
Site Admin

Joined: Tue May 27, 2003 12:44 pm
Posts: 8910
Location: Oceanside, California
Better than that...

On a 14 or 16 you can "pre-bend" the sidebars before tensioning the center lace. We do not use double grommets down the center and get tight tramps without a huge effort.

Image

Use the mainsheet system. Lay the blocks and line on the tramp "unsheeted" from side to side bar... in the center. Add a line to the base of the blocks that can reach around the sidebar, under the tramp and meet the top block. Tie off. Pad the side bars with some cardboard where the line goes around the sidebars. Sheet the system to bend the sidebars in by over 1". We sheet till the tramp gets a little pucker shape along the sidebar. Cleat the blocks and tighten the tramp using moderate tension. Using the vise grips, dowell or just holding the line at each grommet as you go. Tension the aft lace last and then release the block set.

We use this system and get over 1-2 inches of prebend in the bars for over 1 inch after releasing.

Worst loads on a grommet are during tensioning each one... this saves effort and grommets.

_________________
Matt Miller
Director of Parts and Accessory Sales
Hobie Cat USA


Top
 Profile  
 
 Post subject: Bungee Cord Pre Load
PostPosted: Thu Mar 30, 2006 6:27 pm 
Offline
Site Rank - Deck Hand

Joined: Sat Mar 25, 2006 4:20 am
Posts: 1
Location: Okinawa Japan
Here's a trick I used years ago. Pre lace with 2 pieces of seven feet each bungee cord. Do that about twice and then go behind it with small line. Also epoxy the casting to the post. Takes out most of the movement, and prevents wear on the rivets.


Top
 Profile  
 
 Post subject:
PostPosted: Sat Apr 01, 2006 10:09 pm 
Offline
Site Rank - Old Salt

Joined: Wed Dec 28, 2005 12:56 pm
Posts: 686
Location: Los Angeles
Hey Guys,

Other than having a super tight tramp, exactly what are the advantages of having it really tight ???? For some reason, I find that my traction in maneuvering across the tramp is greater with the tramp adequately tightened. Can anyone enlighten me ??? :?

David


Top
 Profile  
 
 Post subject:
PostPosted: Mon Apr 03, 2006 5:43 am 
Offline
Site Rank - Old Salt

Joined: Fri Jul 15, 2005 10:43 am
Posts: 779
Location: St. Louis, MO
A tight tramp adds rigidity to the frame. This makes the boat flex less between teh hulls. i.e. when you pick up only one hull how much difference in height is there between it an the second hull? This is a really short explaination.

_________________
Nick

Current Boat
In the market
Previous boats owned
'74 Pearson 30
'84 H16
'82 H18 Magnum
St. Louis, MO


Top
 Profile  
 
 Post subject:
PostPosted: Mon Apr 03, 2006 5:39 pm 
Offline
Site Rank - Old Salt

Joined: Wed Dec 28, 2005 12:56 pm
Posts: 686
Location: Los Angeles
Thanks Nick,

Your explaination was short but more than adequate. Thanks again.

David


Top
 Profile  
 
 Post subject:
PostPosted: Fri May 05, 2006 5:55 pm 
Offline
Site Rank - Captain

Joined: Thu May 04, 2006 1:23 pm
Posts: 34
I just re-laced my tramp today after also drilling out and replacing all the rivets in the corners. I missed Matt's message about not using Marine Tex so that is what I used. I pre stressed the sides of the tramp sort of like pictured but used a come - a - long instead of the main sheet blocks. Worked great. I also used the tapered wooden dowel and it was a thing of beauty. Fast and secure. Now hopefully the Marine Tex won't be too soft. :?

_________________
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important.
C. S. Lewis (former atheist)


Top
 Profile  
 
 Post subject: Re: Tramp - how tight?
PostPosted: Wed Apr 28, 2010 10:37 am 
Offline
Site Rank - Deck Hand

Joined: Tue Sep 09, 2008 10:04 am
Posts: 16
Location: Magog, Quebec, Canada
Hi guys
I just make this subject live again. :oops:

My last question: which kind of knot I should use for the tramp installation (as per Matt's suggestion)?

Thanks for the info.

_________________
-------------
Hobie Cat 16 1987
Pringle 16 1979 (sold)
Hobie Cat 14 Turbo (sold)
Subaru Outback 2008 BlackPearl


Top
 Profile  
 
 Post subject: Re: Tramp - how tight?
PostPosted: Wed Apr 28, 2010 1:11 pm 
Offline
Site Admin

Joined: Tue May 27, 2003 12:44 pm
Posts: 8910
Location: Oceanside, California
Half Hitches to finish. Bowline at the front and square or figure 8 at the rear castings (line passes thorugh the hole) figure 8 keeps it from pulling out.

_________________
Matt Miller
Director of Parts and Accessory Sales
Hobie Cat USA


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 20 posts ]  Go to page 1, 2  Next

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 12 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group