Trailer design loading keel boat

Meriachee · Apr 30, 2018

The pivot point is A; not at the bow and B; changes with the ramp angle.
The pivot point is actually at the lowest, most forward point which is the bottom, front of the keel. Using a keel stop that can pivot will address all of these issues. My trailer, through a myriad of testing and modifications is working rather well now. The Wordpress link at the bottom shows a whole bunch of pictures detailing what’s been done, and why.
There is no challenge, the only challenge is what you’re going to do when the crane doesn’t exist.

Crazy Dave Condon · Apr 30, 2018

Which boat are you trying to load up onto a trsiler

LeeandRick · Apr 30, 2018

Meriachee said:
The pivot point is actually at the lowest, most forward point which is the bottom, front of the keel. Using a keel stop that can pivot will address all of these issues.

I've always wondered what keeps your boat from sliding back as you pull up the ramp. I've looked at all of your pictures. If the bow eye is moving up as the boat settles that would over tension or under tension that strap, I'm guessing, depending on winch location. Having an eye on the front edge of the keel at the bottom would work but require a cold swim.

Looping a bridal around the aft side of the keel would work. How do you do it?

Meriachee · Apr 30, 2018

7000 lbs of boat does not slide once it settles on the trailer. The strap is snugged up, and is loosened off as it comes out, as a precaution, but the boat has never moved once it's contacted a pair of pads.
The thing that I have found, however, is that the front pads need to be dropped a bit, and raised when it's all done. They are forward of the pivot point and subject to the radius of the curve. It's still a bit of a work in progress, and this year should be the best yet.

Th next secret trickery is the yard tractor. It has a 3 point hitch on a hydraulic cylinder, that can drop the ball almost into the ground. So, this year, no push bar, and see how far the tractor can drop the tongue to lower the trailer so the boat floats off sooner, with less angle. I'll get video.
(if the freakin ice ever goes away)

JimInPB · Apr 30, 2018

kcpilotpat said:
...I have seen a variety of trailer design concepts and haven't really seen any that work very well. ... There must be a good solution...

Can you post pictures of your boat & the ramp where you want to launch or recover?

Meriachee · Apr 30, 2018

JimInPB said:
Can you post pictures of your boat & the ramp where you want to launch or recover?

Yep, they are all contained in the wordpress page with links to videos.
Right below...

Kermit · May 1, 2018

Meriachee said:
Yep, they are all contained in the wordpress page with links to videos.
Right below...

Right below what? I don’t see it, either!

Kermit · May 1, 2018

I bought a drop hitch that lowers the tongue quite a bit. A few guys at our club told me it wouldn’t help much. But it works just the way I hoped it would. The only drawback is the tongue jack is almost too tall to let the tongue go far enough down to meet the ball. Maybe @Meriachee will drive his tractor down the next time I pull my boat out.

Gene Neill · May 1, 2018

+1 on the drop hitch. And along the same lines, I have set my bunks up as high as possible at the aft end. This does more of what the drop hitch does: it reduces the difference between the angle of the floating boat and the angle of the trailer on the ramp. Or the angle of the trailer bunks, that is.

This allows the boat to float on and off in shallower water, and reduces the tendency of the bow eye to slide away from the bow stop as the boat is pulled clear of the water.

On level pavement, the boat does not sit level, it is angled slightly forward. But not so much as to look "wrong". This causes no problems and does not affect the weight distribution in any measurable way.

JimInPB · May 1, 2018

Meriachee said:
Yep, they are all contained in the wordpress page with links to videos.
Right below...

My question was addressed to the original poster, the guy that was asking for help with trailer design. I was thinking that if we knew what the bottom of his boat looked like & if we knew where he planned to launch, then it might help us to help him. Sorry if I wasn't clear on that.

Sumner · May 1, 2018

I made the bow stop...

.... adjustable.

Loosen the two bolts (30 seconds) and slide it forward before retrieving the boat.

Then once the boat is out and has settled back slide it to the boat and tighten the bolts back up.

I also relocated the winch for a better pulling angle but the main deal is the sliding stop. As was mentioned above the problem is the boat pivots away from the stop as the trailer comes out of the water and the boat settles on the bunks.

More on that and also the mod here.....

http://purplesagetradingpost.com/sumner/macgregor-trailer/trailer-mods-17.html

Sumner
=======================================================================
1300 miles to The Bahamas and Back in the Mac...
Endeavour 37 Mods...
MacGregor 26-S Mods...http://purplesagetradingpost.com/sumner/endeavour-main/endeavour-index.html
Mac Trips to Utah, Idaho, Wyoming, Canada, Florida, Bahamas

walt · May 1, 2018

The OP asked about a keel boat which is a significantly different problem than either I or Sumner have with the 26S Macs as they load more like a power boat.

The pivot point is actually at the lowest, most forward point which is the bottom, front of the keel. Using a keel stop that can pivot will address all of these issues

I think you guys are probably on the right track with that pivoting keel stop. What I did with my 26S that loads more like a power boat is an easier problem to solve but I did two things and both of them somewhat revolve around minimizing the lever lenght between where the boat rotates and the stop.

The two things I have done (which I dont beleive are useful with the keel boat) are to move the pivot point as far forward as possible and second, move the stop lower so that it is closer to the pivot point.

Also interesting is that the point where the boat first contacts the trailer are both rollers allowing the boat to move a little as the boat and trailer rotate when being pulled out. Remember that the strap lenght is fixed so when the boat is tightened up against the stop, by having the stop lower than where the strap pull is actually result in the a very slight pulling into the stop rather than away from the stop. The first picture shows where the boat sits on the trailer with just bringing the boat up to trailer, tightening to the stop, then pulling the boat out. There is a gap of just a little over half inch and I can almost get rid of this entirely by one iteration of pulling the boat out a little then tightening the strap again. Ramps vary in slope and I can get close to the same results for a bunch of ramps I have used. I have not been back to that very steep ramp (Site 6 at Lake Havasu) to see how things work after adding the most forward roller - and that ramp is the reason I added that most forward roller..

Second picture shows the two loading rollers that bring the pivot point way forward. I added the most forward one for a very steep ramp. Once on the trailer, the loading rollers dont carry any of the load.

And. I dont think useful for the keel boat loading since you likely are stuck with the contact point being the most forward part of the keel.

LeeandRick · May 1, 2018

With my new trailer I'm addressing the issue using a combination of the ideas above plus my big idea (haha). When I'm building I'm the worst one at taking pictures ( I actually had this thing assembled) but here are a couple to try to explain the design.
In picture 1 you can see the lowered section of the frame cross members and they vary front to rear by 2 degrees, lowering the bow like Gene, but also to give my rudder clearance travelling. 2 degrees on a 26' boat is 12 " bow low which also helps the cockpit drain while on the trailer (center cockpit, scuppers forward).

Picture 2 shows the keel rest looking aft. I have a 9' long shoal keel. The keel rest is sitting on the pivot point (round tubing) on the dolly. This pivot point connects to the first cross member in picture 1. Look close and you will see the tube underneath.

What is yet to be installed, because I need to get the old trailer out from under the boat for some steel tubing, is a 4x3 square tube. This tube connects at the pivot point rises forward at 12.5 degrees between (and connected to) the angle that is sticking forward in picture 2. This tube goes forward, turns up in front of the bow, and will have a bow eye catch. I don't think I will need a winch. At the pivot point there will be 2 hull supports that pivot with all of this mess and several supports on the 4x3 tube. I will have a snug fitting bow guide near the bow eye (remember the boat is coming on level with this support) so the guide will always be at the right place on the bow.

For anyone who is still with me, 1 cubic foot of flotation (FG encapsulated foam) will be attached at the rear of the keel guide in picture 3. Another smaller piece which is adjustable will be attached near the bow eye at water level. I'm hoping someone is saying, aha. This entire assembly will pivot and seek level as the empty trailer is backed into the water. This pivoting assembly allows the keel guide rails, picture 3, to be parallel with the bottom of the keel and not angled up. On a 5 degree ramp all stationary supports will be cleared as the boat floats and the assembly pivots. The unit will work up to a 16 degree ramp before the assembly hits it's stop an inch above the ground. When travelling there are supports installed under the 4x3 at the bow to keep the boat from rocking forward, though the CG of the boat is well behind the pivot.

I'm working on an automated bow eye catch to further simplify (yea right) things.

I can't shoot a video until the boat is complete this October. The keel support is painted and under the keel now to support the boat when I remove the trailer.

Meriachee · May 1, 2018

Kermit said:
Right below what? I don’t see it, either!

If you're reading SBO on your phone, a fair whack of the data (that's a techy term) is missing....

Meriachee · May 1, 2018

Although it's probably unrelated, there is a -perception- that because the bow eye is not firmly attached to anything, that the boat isn't properly loaded. The regional rent a cops must have a real day job as load masters, and like to tell you about it. I'm sure this scenario exists elsewhere. Not that this matters, the point being that the boat does need some form of positive stopper to prevent it from moving forward. Straps hold it down. My keel stop will prevent it from moving forward, but the thing will not prevent it from moving up, and if it were to break the straps and move up and forward, well, I wouldn't want to be in the truck, cuz it would be coming to sit with us.

LeeandRick · May 1, 2018

To the OP, If you don't want to build a new trailer use my old two winch idea. I added a second bow eye but I don't think it is necessary if your bow eye is strong. In the photo the second winch is above the bow because I used it to raise the mast also but anywhere above the bow eye will work. To load or unload you crank both winches, the top one raising the bow sinking the stern and the other one to pull the boat to the bow stop. I use a brake winch on the lifting winch. Mark your bow where everything needs to stop. Worked well on my O'Day. The only reason I'm not using this method on my new trailer is

and I wanted to test my new method more thoroughly and not have to build a place to stand to crank winches. All the stuff you are looking through to see the winches are a mini dock attached to the trailer so I never get wet.

watercolors II · May 2, 2018

As explained the boat is floating level on the water and the trailer is sunk on the angled ramp. Then the trailer is pulled from the water at an angle to the boat, the stern of the boat has to sit down on the back end of the trailer which causes the bow to rise up and pull back away from the trailer bow chock!

Most of the the trailer photos with the boat I see in these blogs, the first thing I see that the winch at the bow is pulling down on the bow eye when the boat is out of the water. In my 25 years of recovering trailer sailboats of all makes, is that the winch should be pulling up slightly when the hull is in it’s final resting place. Move that winch up!

A bow roller in the proper place on the trailer will help lift the bow up out of the water and sink the stern as the winch pulls the bow towards the trailer bow chock. This makes the hull match more of the angle the trailer is at under the water. When the stern does sit down on the back of the trailer the bow will lift up away from this bow roller. With the boat in it's proper resting place on the trailer place a single roller under the bow back about 18 inches from where the bow makes it's transition from vertical to horizontal and let a gap of about 3/4 of an inch under the hull as a starting point!

Keel guides up close to the bottom of the hull will make centering the boat on the trailer a first time every time event. These guides must be high on the keel because of the boat floating above the trailer and the keel guides on the ramp.

Meriachee · May 2, 2018

Not quite. The boat sits down on the front pads and settles on the next set and so on until the stern makes contact. It does not contact the back ones until it’s fully rotated on the trailer. The only place that has any form of constant contact is the keel guide and even that rotates.

Kermit · May 2, 2018

Simply put, we’re trying to float the boat onto the trailer. It’d be best if the trailer were parallel to the boat.

Trailer design loading keel boat

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