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Old 03-10-2009
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Tilting aft section on new trailer for MacGregor 26X

I'm replacing my old, rusted out, and long overburdened stock trailer with a new heavier duty dual-axle trailer but need to figure out how best to configure the rollers and such for my MacGregor 26X hull.

Here's what I have now:



Here in Finland, boat ramps tend to be short and with a gradual incline, and the most you get the trailer into the water is typically just up to around the tops of the trailer fenders, so nearly all trailers of this size have hinged tilting aft sections and all rollers (no bunks) so that the boats can be winched up onto the trailer from a fairly shallow depth, and the boat is entirely lifted out of the water as it is slowly winched onto the trailer rather than just the bow being lifted a bit while the aft remains floating until you pull the trailer forward (as has always been the case, for me at least, in the US).

Unfortunately, all of the local stock trailer models are designed for a V-shaped hull (i.e. typical powerboat), and have a single centered tilting roller section for the apex of the V-keel, which I fear will put far too much strain on the center of the Mac hull before the boat is winched far enough up onto the trailer to distribute the weight more evenly (I don't know for a fact that it will do any damage, but I'm concerned that it will). So I'm trying to work out how I might need to modify the tilting section of the trailer in a way that won't stress the Mac hull as it's being winched out of the water.

E.g. here are a few examples of what I have to work with (pretty much all of the local brands are the same). Note that the last two photos are of slightly smaller single axel models, but the features and loading process are the same.





(note the tilting section in the last photo)

I'm wondering if anyone here has a trailer with similar tilting aft section, and how you've configured the rollers, and what your experiences have been.

Should I be worried that there will be too much pressure on the center of the hull if there is only the single narrow tilting section (which will briefly bear a major portion of the boat's weight)?
Here at least is what I'm thinking of doing. The diagram isn't perfectly to scale, but should be clear enough. The blue bits are the parts that tilt.


Initial approach (blue portions portion tilt down to match angle of bow/hull):


Half way loaded (tilting portions fully supporting weight of boat, fully out of water, boat pointing slightly upward):


All the way loaded (boat settled fully onto trailer and rests evenly on all rollers):


When loading, the full weight of the boat will be only on the blue rollers, at least momentarily, until the boat is fully winched up onto the trailer. Should that be enough support, or does it look like there will be any unacceptable pressure points?

Would just the stock, center rollers be enough support? I.e.



Or is that too narrow and will stress the hull? (remember, all of the weight of the boat will be resting/rolling only on the blue bits when loading)
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