I bought a used one of these today: http://www.boatrailer.com/images/HPIM0233W.JPG
The previous owner had taken off the rollers and cradles, and moved the axle very far forward on the frame (for an A cat).
I have a Nacra 5.8 to place on the trailer, and would like some input on proper trailer balance, and can't seem to find a thread on this topic (if there is one, please point me toward it). His recommendation was generally to keep the forward beam above the axle, and not exceed the tongue weight (is this possible on a 650 lbs cat?) I've read in other posts that this is where the center of balance is when rigged. Could I get some recommendations for :
-locating the axle on the frame
-vertical distance for the rollers and cradles above the ground (these are adjustable by about 5")
-and placement of the cat on the trailer assuming I'll be winching the mast up and launching on a very flat concrete boat ramp?
He had also placed the front cradles on top of two 2" blocks, but I'm assuming I'll need to remove one or both of them, as it looks like it would place the boat at too high an incline even with the rollers extended as high as they will go. The Nacra's hulls are so tall around the cradle point, is there any benefit to having the boat inclined at such an angle on the trailer?
1st, Put the front cradles under the main beam of the boat. There's a bulkhead there that will support the weight of the boat and you standing on it. This isn't really optional, long-term.
I don't know about exceeding tongue weight, but you obviously want to make sure you have at least 40-50 lbs or more so that it tows correctly.
The rear cradles ideally would be below the rear beam, although this isn't as crucial imo.
If the boat is inclined on the trailer it will drain more easily, but I would opt for it to be level if possible. You can always tilt it up. IMO they are a pain in the ass when they are declined forward, but that's more likely just the boats and trailers I'm experienced with. It will allow them to collect some water in the bows that will be heavy to drain, though.
Pile of Nacra parts..
Regards axle placement, most trailers have leaf-spring mounts welded to the trailer frame, sometimes there are studs on top of the leaf-springs that will fit into a hole on the frame and then square type u-bolts attaches the leaf-spring to the frame, you need to look at your leaf-springs to determine how they attach to the trailer frame, look for old rust marks on frame indicating old u-bolt bracket placement. On my trailer, the front of the leaf-spring is looped into a circle, fits into bracket, bolt slides through bracket and through loop, the back of the leaf spring is straight and slides into a slot type bracket. To mount leaf-spring, slide tail into slot, put loop into bracket, slide bolt through bracket and loop, attach nut to bolt.
Thanks Turbohobo and Yurdle, I got the axle moved back and the cradles adjusted. At first we tried it with the beam directly above the cradles, but after a short drive I found it just too bouncy. Shifting it back a bit, say 4 inches or so, made all the difference. The center of balance of the boat is much farther forward than I thought it would be, and I'm guessing when trailering with the entire rig attached it will shift even further forward.
Now, if I can just find a good glass guy who can fit me in before the end of the Mayan calendar...
i have owned several nacra 5.8's
1) starting with the tongue weight, most sources suggest having 10-15% of the gross vehicle weight GVW (everything plus the trailer loaded) on the tongue. first thing to do is balance the empty trailer by moving the axle to a position where the tongue is holding 10-15% of the trailer weight. put a bathroom scale under the tires and tongue. double what it says when you do one tire to find the weight on both tires.
2) to determine where the center of the cat weight is, i find that it is directly under the shroud chainplates. i know this because when i use cattrax, that's where they are to balance the boat.
3) place the cat on the trailer and center the chainplate above the axle or just slightly forward. when you add the 50# aluminum mast onto the trailer, more of the weight will be forward of the axle, adding to the tongue weight.
4) move the trailer crossbars to have the rear one below the rear crossbeam on the cat and the forward one slightly in front of the cat's front crossbeam. there is a bulkhead inside the hull which is about 12" in front of the hull's front crossbeam. this will allow you to tie the hulls where the hull can best support it.
here's how i load mine. (copy the URL into your browser, i can't get the photo to load)
by the way, a 5.8 only weighs 410lbs, not 650lbs.
Edited by arch on Jul 05, 2012 - 12:15 PM.
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