Bunk Settings/Adjustments

[Zinger88]

Ok..so I spent the weekend replacing my 2x4 on edge side bunks with 2x8's flat and also replaced the keel rollers with a 2x8 bunk (pictures to come later). For those who've replaced their keel rollers with bunks, can any of you tell me what the typical height difference is between the keel bunk and side bunks for a DSII?

[Zinger88]

Here's the before/after photos of my repairs and upgrades to ol "Rusty" (yes…I even named my trailer ).

First I dry launched the boat onto the hard utilizing a few discard tires that I picked up for free from Discount Tires. Using Rusty's tilt feature, the boat slid easily off the trailer onto the tires and was perfectly balanced with one tire being placed at the aft end of the CB trunk and the other at the forward end. I then placed two additional tires on either side of the boat basically for peace of mind even though they weren't actually needed.

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[Zinger88]

Here's what Rusty looked like once the boat was off.

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[Zinger88]

After doing a lot of reading/research on this forum, I decided to replace the side-bunks with 2x8x6' flats and also the keel rollers with a 2x8x10' bunk. The bracket hardware and bunk carpet was picked up at Academy and the bunk material is pressure treated lumber from Home Depot.

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[Zinger88]

I had some scrap galvanized plates which I cut to size and used under the bunks to provide more of a platform for the bunks to sit on.

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[Zinger88]

As noted in a previous post, I had a real issue with the hull on the starboard side "oil canning" from sitting on a 2x4 on edge bunk.

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When I pulled the boat back up on the trailer from the hard it was amazing to see that there was almost a 1" gap between the bottom of the hull and the new bunk on the starboard side with the boat sitting level on the trailer (both side bunks were at equal height).

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[Zinger88]

I'm going with the theory of allowing most of the weight to ride center-line on the keel bunk and the side-bunks are utilized mainly for lateral support when traveling. I let the boat sit on the trailer as shown in the above photos for almost a week before I had her out in the water and "presto!"...no more oil canning. The hull settled back into place and she now sits nicely with equal support distributed between the side-bunks. This was similar to what klb67 said had happened to him in another post.

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These new bunk upgrades have made a HUGE difference in 1) how the boat sits on the trailer and 2) the ease of launching and retrieving from the water. Well worth the weekend spent working on it!

[GreenLake]

Cool! Nice pix.

[chocolatehauler]

Nice i'm redoing bunks on my trailer also. I like what you did. Hoping you don't have a patent on it.

[Shagbark]

It seems without rollers the boat would have a tendency to move off-center when trying to put the boat on the trailer. The bow hitting that initial roller helps line everything up. How has your experience been without the roller? How do you make sure the boat stays on-center?

[Zinger88]

I mainly beach launch at the lake since we have an area close to the house where I can pull up to the water with the trailer. I utilize the tilt feature when retrieving and have found the trick for us at least is first placing the bow on the back of the keel bunk to line things up and then my wife stands along the side of the boat (she's only in knee deep water) to help guide it as I winch it up onto the trailer. I watch the front of the bow as it's sliding along the keel bunk and can pretty well sense if things are getting off line and I'll also stop periodically to check alignment. That technique has worked for us thus far, although I am debating about adding some guide-ons to the trailer but haven't made a final decision on that yet.

[GreenLake]

My contention is that bunks are actually easier than rollers, because the hull can slide along them on any direction, meaning that the bow, for example, always moves towards the winch. With rollers, if the boat is askew, you may get the effect that the boat may maintain that angle.

I use a notched rear roller to capture the bow (with the sharp keel at that point). I then winch the boat to close to where the bow would meet the next roller. At that point, the boat "pivots" on the one roller and I can align it (without getting into the water). Shortly after the bow passes the second roller, the bunks will support the weight of the rear (since I've set my rear-roller a bit low). At that point, the back of the boat will slide in the direction of the pull, so all I need to make sure is that the bow continues to stay in line for the front rollers (if I had a keel bunk for the forward end, that would, of course work just as well, because at that point the boat is lined up and would follow the direction of pull).

I do not use the tilt feature for retrieval, but need to drive the trailer in a few feet more than for launch (where I do use that).

The only time I need to stabilize the boat more than what that first roller can do, is when there is strong wind/current/wave action. For wind and current I use a long stern line from shore, waves are a different issue, because they can lift a fully aligned boat off the bunks and bodily shift it. Those conditions have been among the very few times that I've had anybody in the water.

[efoconnor]

Can you send instructions as to how you used the tilt feature to unload the boat. I have used it to launch and retrieve and am interested in getting the boat off the trailer on land to make repairs. My bunks are much smaller maybe 3 inch’s and shorter maybe 4 feet. They also taper towards the bow. I believe this may have caused or contributed to a 16-18 inch crack in the hull. Also if possble send details on the bunks. Thanks in advance. My heart sank after finding the crack

[GreenLake]

First, here's a picture of my trailer. People have done wider bunks than these. So by all means, take that as a minimum. They extend nearly to the transom when the boat is loaded.

The picture also shows how I position the trailer so the rear-most roller is just at the water level, so it can grab the bow in the notch it has (that detail becomes visible in this photo if you click on it to enlarge the view). That roller is also 1-3" below the "level" made by the other rollers which helps transition the rear of the bot onto the bunks during retrieval, as the bunks will begin to "lift" the boat off that roller earlier. It also means that roller will not bear any weight in storage.

Now, to launch onto the hard: I place a bit of carpet where the hull will end up. Then I tilt the trailer until the boat starts to move. Usually the transom contacts the ground pretty immediately, at which point I pull the trailer forward. The bow will descend while rolling on the various rollers, until the trailer is out from under it. With a trailer that lacks the tilt feature you might need to disconnect the trailer so you can tilt it as a whole and somehow manually pull the trailer out.

Retrieval: I find that I need to limit the amount of tilt, so I lash an old rope around the trailer tongue to let it still tilt some, but not the full steep angle (if the angle is too steep, the bow will "dig in" between rollers). I roll the trailer so the rearmost roller touches the bow, connect the winch and put a bit of tension on it. Then I support the bow going up that roller. With help of a block of wood or two, I can manage that process by myself. Once the bow is on a roller, I simply winch the trailer under the boat. I connect it to the car only after the boat is loaded. (I imagine this would work pretty much the same for a non-tilting trailer).

Hope this helps. (If you want to discuss your repair, please make a new topic for that).

[efoconnor]

Hi Greenlake: how do I access the photo? Indicates I am not authorized to view. Could you send to efoconnor@gmail.come? Thanks in advance