What is this trailer do-hicky

[marc]

OK. I've got this spring loaded pin on my trailer tongue and I don't know what it's for. Picture of it is in the 1st photo. Second photo shows where it is in relation to everything else.  Can anyone enlighten me?
Marc

[bob lamb]

Yup;
  That's a "magic tilt" feature on your trailer.  It's designed to "dump" your boat when launching. Compac used a lot of those rigs.  I had one but never used it...never had the confidence that I'd be able to get the boat back on the trailer.

Keep it pinned, old salt!
BobL

[Billy]

Bob is right. I have the same performance trailer on my 19. Used it once, and thought it was more trouble than it was worth. And you really can't use it when retrieving because the weight of the boat pushes the frame down on the spring loaded pin and you cannot release it. You would have to hold the pin out while the boat is wenches onto the trailer.

I find my tounge extension to be way more useful when launching in shallow ramps. Here is a link for a do it yourself...
http://cpyoa.geekworkshosting.com/forum/index.php?topic=5378.0

[marc]

I see how it works now. I was thinking I needed to get an extension and your photos Billy are very helpful.

Ideally I'd like to launch the boat in the spring and then get the trailer tongue modification done - so maybe the 'magic tilt' feature would be useful for that 1st launch. What will cause the boat to tilt back at launching to get the frame to tilt? Right now there is no pressure against the pin. The trailer is firmly committed to the 'no-tilt' position. OTOH, if there was pressure against the pin, I would guess that I'd have a very tough time getting the pin to move at all. Please reveal more magic tilt secrets.
Marc

[JTMeissner]

For an example of launching with a tilt trailer: http://www.youtube.com/watch?v=KdXL8W4RYTo&feature=relmfu

The same guy has an example of retrieval using the tilt feature.  Discussed previously here: http://cpyoa.geekworkshosting.com/forum/index.php?topic=5275.msg37298#msg37298

Granted, no keel, but the concept is the same.  You need some steepness to the ramp to help pull the boat off the trailer, and some reason to not back up the trailer any more.  Right now, with reservoir levels about three feet below where I normally sail and thirteen below pool, I may have to try this as I will soon run out of ramp in the water.

-Justin

[marc]

Hello Justin,
Watched the videos & read the posts. Like Skip said in his post, with the bunks curved to the shape of the hull, can't see the boat sliding off as shown in the video. In that case, seems to me that a CP 19 has to float off the trailer.

When I picked up the boat to bring it home, the bunks were straight. I had to adjust them so they would cradle the boat. Maybe those straight bunks were there for a reason & not just an oversight by the previous owner. I was reluctant to drive 300 miles home with just 1 contact point of the hull with the bunks. On the other hand, I suppose I could straighten the bunks when I get to the ramp to launch. It would be time consuming but I would only do it for the 1st launch. After that  I'd use  a tongue extension.

Still not sure though that the load will shift sufficiently on the ramp so that when I pull the pin, the trailer will tilt.

Marc

[Billy]

Marc, no need to do all that. Plus I am not sure the bow eye on a 19 could support it's own weight, like that 14' aluminum john vote i the video. It is apples and oranges.

The ramps don't have to be that steep to launch a 19. You'll be surprised how easy she just floats off the trailer.

[JTMeissner]

Billy, concur on the major differences (flat bottom and weight) for the jon boat.  I'll assume Hutchins gave us tilt trailers for a reason though...

Marc, regarding the bunks.  My original ones were very curved and conformed to the hull their full length.  The new ones I put on were straight, but over time have bent into shape and required adjustment.  Where I had trouble with the original ones was on a shallow ramp and how far to back the truck in the water to free the boat from the trailer.  I've lowered the rear of the bunks to prevent an upward angle that the boat has to overcome when traveling backward on the rollers.  On a shallow ramp, trailer was sunk, truck was snorkeling, boat was almost floating, but required a lot of effort to push off the trailer (without using the momentum technique to overcome bunk friction).  On steeper ramps, the stern pops off the trailer before getting too deep and is very easy to launch.

I see the side bunks as guides, not to be weight bearing, so if they have an upward curve in the rear I may not be getting the full weight of the keel on the rollers and potentially warping the hull.  They do curve towards the front and nicely point the bow eye in line with the winch post. 

And I have a 16, not a 19, so the weight is a different consideration.  When I have used the tilt feature, it's usually for a matter of a few feet of ramp.  With the 16, my father and I can push the bow up, allow the trailer to tilt, and the boat rolls off.  May be a different story with the 19...

Last thought;  I still think an extension is the best/easiest solution.  It's just dropped down my list of things to do as a "built-in" solution exists, and won't make a difference if the the lake is so low I run out of ramp.

-Justin

[marc]

Good point Justin. All I need to do is straighten the back end of the bunks to launch.

What I still am confused about is that right now the trailer is firmly in the 'no-tilt' position. There is no contact between the part of the frame that tilts and retaining pin. I am concerned that when I am on the ramp and if I decide I need to use the magic tilt feature, the frame will not tilt since apparently weight of the boat is too far forward on the trailer.

Comments?

Marc

[JTMeissner]

Marc, I might get a good chance to try various things and take pictures this weekend which may help the discussion.  Lake levels are still down, so ramp operations may require extra work.  Also no crew, so we'll see.

Thoughts; I didn't have enough weight on the tongue, so I moved the winch post forward, bringing more of the boat in front of the axle, which makes the static position ensure that the tilt could not accidentally function.  The goal here was tongue weight for towing, not anti-tilt, as long as the boat center of gravity is in front of the axle, the tilt should not function. 

Sloped ramps help in two ways.  The angle of the ramp may allow the center of gravity to rotate behind the axle which would allow the tilt function to work.  If the ramp is this steep, I would think the boat would float off without much problem.  Secondly, with rollers instead of a keel board, gravity may just pull the boat backwards.  If I have to push, it's "downhill," and every little bit helps.  Rolls back far enough, CoG moves behind axle, trailer tilts, increases effective slope, boat rolls downhill even better.  You can see this effect in the video, gravity pulls the boat, then tilt, then down into the water.  Remember, I am only pushing a 16 though (and young(ish), definitely foolish).  Improperly set up bunks may add too much friction or an uphill surface that fights the gravity assistance provided by the ramp slope.

In an apples/oranges way, the video shows launching without a ramp more than tilt function.  We'll likely never be able to launch our shoal keeled boats without the trailer being in the water to some depth.  With the boat pretty much rolling off the trailer, not sure the tilt was necessary.  Upon retrieval though, the tilted trailer gets that aft roller way down to the waters edge and assists with recovery.  We still have our keels to get under.

So, when used before on a shallow ramp, the trailer submerged in about two feet and change water (over the knee at the stern), but the boat was still "stuck" on the trailer, tilt pin put, water up to door frame of truck, and boat not deep enough to be fully buoyant.  Push bow of boat back and up, trailer tilts, boat rolls into water.  On retrieval, tilt pin out, raise "A" frame of trailer to tilt, get keel over first roller, but nosed into second one, step on trailer tongue near tilt point to flatten trailer, insert pin to lock, this action lowers the second roller and I can now winch on completely.

My pin configuration is different, fully removeable and through the trailer frame (and a potential source of weakness according to descriptions elsewhere on the forum).  I'm guessing yours either is keyed in some way, pull forward and twist so a detent not seen in the photo can lock the pin behind (in front of) the aft metal plate, or when pulled forward, you can tilt the pin enough so it won't snap back through the hole in the aft plate.  This will keep the pin from preventing the tilt from occurring, should it be necessary.

In most cases, tilt is not necessary.  It's an added feature that has little drawback if not needed.  But, in the right conditions, it may be necessary if you want to launch, so all the better for having it.  Got to have a good winch, cable/strap, winch post, and regularly checked bow eye.  Hope this helps.

-Justin

[MacGyver]

Marc,
I pulled today thinking that I would have serious issues, and ended up not the case.
I could have done it myself, but much easier with my wife.

Read this post maybe it will help with the pulling.
http://cpyoa.geekworkshosting.com/forum/index.php?topic=5724.0

Launching was tough my first time... but hey, I am used to using lifts and Acme Hoists to pull and launch boats, so I had a learners curve myself.....and rough chop doesnt help to launch or pull. LOL

I am of the belief now that you wont need a extension if you have 4 wheel drive... the ramps are slick and you will get the back tires wet.

My tires are 31x10.50, r15 and only the rubber up to the rim was wet.

Mac

[marc]

Justin - I am hoping that the COG will change enough when the trailer is on the ramp so that the boat will just want to tilt back. And your point is well taken that the boat is sitting on rollers and the direction I want to go is downhill.

I took another look at the pin to see how I can hold it in the open position. Although it is not keyed, I can pull the pin back far enough so that I can get its tip behind the rear plate that holds the pin in place.

Mac - Thanks for info on negotiating the mid roller. As far as my tow vehicle goes, I need to rent a truck for a day when launching or retrieving. I've used a 10' Uhaul before without problem. Two wheel drive. It sure would be embarrassing though to get it stuck on a ramp. My last boat had a tongue extension so I was able to keep the tow vehicle wheels dry & the ramp wasn't too steep.

Marc

[Billy]

This thread & Mac's other thread about the rollers got me thinking about another trailer mod I have done.

I replaced my old rollers with a 2X12 PT wood plank.



When I go to launch, We tie up a stern & bow line and have The Admiral walk down beside the boat with the lines. Before I even back down the ramp, I unhook the bow eye from the winch strap.



I back down the ramp, with my wife holding both lines. keep going back until she floats off.  Just like that. Have the wife tie up the lines to the dock and I'm off to find a parking space. I never have to get out of the truck and neither one of us has to get wet while launching. Doesn't take 2 minutes. And with my new extension I don't even get the tires wet.

You don't want to "PUSH, SLIDE, FORCE, or SHOVE" the boat on or off the trailer. You want to "Float" it on and off. Get the trailer low enough in the water so the boat moves up off the trailer. That is why the trailers have the smaller wheels. Of course there is a trade off when towing at high speeds and long distances.

As to rollers VS keel board; Skip and I have gone back & forth on the pros VS cons and there are plenty of other threads about it. But I just realized another pro for the plank....

Because I unhook the tow strap before I back down, if I had rollers I would be afraid that the boat would roll back off the trailer and onto the ramp before I had a chance to get her down to the water. Some of the Ramps I use are steep.....and some are shallow. In either case, because the plank supports the entire length of the keel it has more surface area touching the keel, it provids more friction to keep the boat on the trailer until she can float off (float up).

Anyone have any experience with a boat rolling off the back of a trailer while backing down a ramp?