Bunks for 14' Springbok boat trailer

[FarmerSid]

Hey All! New to the tin boat scene. Picked up a 90's 14' Springbok aluminum boat with Evinrude 9.9 for my young boys to learn the tiller trade. No trailer. Picked up a used trailer for cheap that needs a bit of work. No bunks or rollers on it. Been told to go with the tilting bunks. Been searching but can find too much. Wondering if you all would lend an hand. How long should the bunks be? How much of the boat should be overhanging the bunks? Any advice would be appreciated.

Cheers!

Sid

 

[richg99]

How long should the bunks be? How much of the boat should be overhanging the bunks?

The bunks should extend from just beyond where the bow turns up...and should extend past the transom end of the boat. It is important that the stern, transom, and motor be supported fully. Without the full support, some boats have developed a "hook" (downturn in the hull) which can make it difficult to get on plane.

Since you are starting from scratch, rather than carpeting the bunks, you might consider just topping your bunks ( DO NOT USE TREATED LUMBER) with a PVC gutter downspout cut in half. That will leave them slippery and make loading and unloading very easy.

Be certain to keep the strap on the boat until you get the stern over the water. If not, and "early launch" can occur. Ha Ha

regards, richg99

https://www.forum.tinboats.net/viewtopic.php?f=3&t=40137&hilit=bunks

 

[lckstckn2smknbrls]

Where you position the boat on the trailer will affect the tongue weight of the trailer. You will want about 10% of the total weight of the boat, trailer, motor, fuel and whatever you will have in the boat when it is towed on the tongue.

 

[FarmerSid]

Hello again guys! Working on this trailer and need some help. Wondering if someone can give me some measurements. How far apart are the bunks? How long are they? How far past the end of the trailer do they go? Does the end of the boat line up with the end of the bunks? How high off the trailer frame are the bunks? For a 14' aluminum, what's the distance from the end of the trailer or bunks to the roller at the winch? What's the distance from the winch to the ball hitch? I know that's a lot questions but that info would be a great help. Boat is in the water back at the cottage.

Cheers!

Sid

 

[richg99]

How far apart are the bunks? They would normally be positioned to drop between the strakes on the bottom of the boat. You will have to measure. I like them wider, rather than narrower.

How long are they? The length depends on the amount of "upturn" of the hull. The bunk's supporting ends could end just after they no longer touch the hull. Many make them longer yet, to give them standing room when launching or recovering the boat. You will have to measure.

How far past the end of the trailer do they go? Does the end of the boat line up with the end of the bunks? The bunks would normally end just beyond the transom. Support for the transom and motor's weight is important.

How high off the trailer frame are the bunks? I like them as low as I can get them. That way, you don't have to back too much of your vehicle in to launch, especially on a shallow or less angled launch.

For a 14' aluminum, what's the distance from the end of the trailer or bunks to the roller at the winch? Depends on the boat. Most 14 foot boats are NOT 14 feet long.

What's the distance from the winch to the ball hitch? The winch stand is often moved forward enough to put 10 to 15 % of the boat's weight onto the ball. Otherwise, you may get fish-tailing of the trailer when towing.

You cannot, normally, determine all of these distances without both the boat and the trailer at the same location.

How this helps, richg99

 

[Captain Ahab]

I topped my bunks with old cutting board plastic and countersunk SS screw - I did use treated lumber but the wood never touches the alum boat, just the galvanized trailer

works great and the boat slide easy

 

[FarmerSid]

Thanks for the info. Good stuff! Kinda hoping that someone with a 14' ft aluminum boat and trailer combo could get me some measurements.

 

[richg99]

I understand. My boat is kept in a storage facility and EVERYTIME I want to do something on her, I have to go get the boat and get my measurements...before I can proceed. The guys that keep their boats at home have a definite advantage.

Even if someone else had a 14 footer...I can assure you that your boat and his boat would be different...and his trailer and your trailer would be different.

richg99

 

[DaleH]

If you use PT wood, just use vinyl gutter material to cover them, see:

https://www.forum.tinboats.net/viewtopic.php?f=49&t=41391