I agree with your selection, but I "car-top" my Sunfish, so I can only reply in theory.Yeah I hauled mine upside down in the back of my truck last season. It was tough as I mostly sail solo, but I made due. I definitely want to go right side up now that I have a trailer. I'm liking John howards design. That may be a winner.
Yeah, and I'm using an 18' boat trailer for this. It was sprung way heavy, but i took apart the leaf packs and am just using the main leaf. The trailer itself is pretty heavy, so it's pretty soft now. I may even go so far as to weld on some small boxes with scrap steel and add a couple bags of sand or something. I've got an ad on craigslist looking to trade this for a jetski trailer or the like, but this will work for now.I agree with your selection, but I "car-top" my Sunfish, so I can only reply in theory.
Having acquired a Sunfish with loosened internal blocks, I'd wish for a trailer that supported the Sunfish as though it were on water. (Or as though I were to traileran egg). Working backwards from The Ideal Support, I'd want a hammock, bunk-bed mattress, or a net of nylon strapping; admittedly, none of those are practical, but most trailers are over-built for ~140 pounds, and regardless of what you load on your trailer, every pothole and speedbump will hammer the load—twice.
If one is going to use wood, I'd go for John Howard's design, but with 1x's all around, or pressure-treated 5/4s. "Yes" to cushioning—but strap the Sunfish down tightly, so that the cushioning is fully compressed.
JMHO—just based on my "loosey-goosey-egg" theory.FWIW...
can you post some pictures?I spent a bunch of time trying to pattern and cut bunks, crossways and lengthways for my sunfish, and decided there has got to be simpler way. Knowing that the chines are at the strongest point, I decided to concentrate there. What I ended up with is two 2X4 that run across the trailer. On the end of each I attached an upside down U-shaped saddle of 2X4 pieces, spaced to be right under the chine. By doing one at a time, I could get optimal contact and angle, using a through bolt and woodscrew to lock in place. Padded each one and viola. And for longer term storage I just turn the boat over on the same blocks and pads. I can also just pull off the thwart-wise 2X4s and use the trailer for other things (the Old Town or the Laser or a pile of 2xX lumber)
• There are some spring-loaded steel shock-absorbing "isolators" that are discarded after shipping "ride-sensitive" equipment. They are about 2" tall, with a 3" base, and attach using four screws, with a single threaded hole at the top. I have a few, but you'd need a couple-dozen to isolate one 130-pound Sunfish."I've tossed around the idea of putting the bunks on some sort of springs, like the cab on a big rig, but I think that would unnecessarily complicate things."
I also liked the John Howard set up. I placed the bunks over as far as could on the trailer and used a treated 2"x6"x8'. I used the compass method to trace the cuts on the bunks. In retrospect, I would have used 2"x8" though. I did not cut the bunks at an angle, but I figured out an alternative. The clearance between the hull and the supports under the trailer was about an inch. It seemed a little too tight for me. So I cut some other pieces to lift up the bunks. When I screwed them into the bottom of the bunks, I noticed that the outer frame of the trailer was a little higher than cross rails. By placing the cut wood on the outer rail, it caused the bunk to lean in to the center of the trailer a little ways. Plus, the bunk is resting on the extra piece of wood between the forward cross rail and the out side rail towards the front of the trailer. It is far from perfect, but I think it will do!View attachment 8086 View attachment 8084
It took awhile to get computer time (teenagers!) but these are the saddles I use on crosswise 2X4 . you can see the thru bolt, which I placed above center to give more support and less chance to split. Once I got the tilt right, I put in a screw to lock it in place. And I had to notch the middle of the crosspiece to accommodate the center keel and keep center of gravity low. In the photo, the boat is upside down for the winter, with heavy plastic cover sheet, but when right side up, it sets right at the chine.
View attachment 8082View attachment 8083
I used John Howard's design, and it looks very similar to Danpal's design above. I've read that you should always support the Sunfish at its chines, as that is structurally the strongest location. There is very little internal structure or support inside a Sunfish, almost none actually, so any bump the trailer hits will translate into flexing of the bottom of the hull. Those flexing effects can cause the foam blocks to come loose, and eventually can cause structural weakness in the hull that manifests itself as the "oil can" sound that older hulls can make when riding over waves. If you're mainly a cruising sailor, it won't affect you, but it's the death knell of a racing boat.
Since I've built my bunks I've seen a lot of trailers from higher level Sunfish racers, and they almost to a person carry theirs upside down, but that really hampers your ability to sail solo.
I like a variation on option #1 which takes a little more work but I think it provides better support. It's a contoured bunk design that I found on the Sunfish Sailor Yahoo site. John Howard provides a whole photo essay on how to build it under "Skylarkmk1s Trailer" in the photos section. I've used it for 2 years and really like it.
I can't find the photo essay - I think maybe it's disappeared? Anyone have any ideas where I can find some info on how to build the bunks below? They look like they're worth the effort. I have to get a hull crack repaired after my latest 4 hour trailer with standard 2x4 bunks that were in the middle of the hull.
Thanks,
Charlie
Very nice work, oldpaint!I did build a removable trailer bunk system based on the John Howard design. (When I'm not hauling the sunfish I take the cradle off the trailer and use it with a plywood box as a utility trailer.) It has 1x8 pressure treated carpeted boards sitting on treated 2x8's. The cross bracing is treated 2x4's. I've been playing with webbing crossing from the top of the port bunk to the starboard side bunk to support the keel, but its not shown in these pictures. Also the bolts holding the cradle to the trailer aren't tightened, since I wasn't traveling anywhere, just taking a few pictures.
Thanks TagVery nice work, oldpaint!
Geophizz, The mounts for the bunks came with the trailer (from 1993 or so) and are pivoted, if thats what you mean. The same bunk mounts are used in the utility box pics below. To get the curve correct, I built the cradle in one piece, a lot of trial and error work, When I was happy with it, but before carpeting, I took off the top 1x8 (lag bolts hold it on) sawed that and then sawed the curved 2x8. All of it was done by eye, hmm that looks pretty good ,rather than following a plan.Nice work Oldpaint! How did you get the back of the bunks to flex? I wanted to do that on mine, but could never figure out how to make it work right.
Danpal, here are some pics:Yeah, and I'd also like to see how you incorporated the plywood box for the utility trailer (something I've been thinking about for a while).
Thanks Kent appreciate that. The cleats aren't my idea, Geophizz came up with that.The hinged end is a great idea, as well as the cleats!
Just a mention that rollers elsewhere than the keel will put a serious bend in the hull. I do have to change my ramp design next spring!"...A key to his design is that is also incorporates the use of keel rollers as the actual load points. These bunks should be equal if not just a hair less in height to allow the keel rollers to engage the load..."
Just a mention that rollers elsewhere than the keel will put a serious bend in the hull. I do have to change my ramp design next spring!View attachment 12969