: Bunk set up
Shellback 11-30-2009, 07:19 AM I'm redoing a trailer for my project Starcraft Superfisherman. The trailer has keel rollers on the x members, and will have 2x6 bunks, 8 feet long. Are the keel rollers supposed to support weight while on the trailer, or are they just an aid in centering and protecting the keel? I'm figuring on placing the trailer under the boat, then lowering the boat to the keel rollers. I'll then raise the bunks to contact the hull, mark the spot, then raise the boat some and adjust the bunks up say, 1/2" on each side. I'll then put all the weight on the trailer. So should the keel rollers be able to move some by hand, or should there be alot of weight on them. Thanks!
The keel rollers are there to help winch the boat onto the trailer. The boat shouldn't be touching the rollers when trailered or the rollers will deform. Ideally the keel will stay in contact with the rollers until the last foot or so of winching but every ramp is different. I'd say 1/2" of clearance is a good goal to shoot for.
If you are re-carpeting your bunks, you might want to consider getting a sheet of UHMW plastic and carving it into strips on a table saw and screwing it to the bunks. My current trailer is the first I've had with it and I love it. UHMW has just enough friction that the boat doesn't slide off the trailer on accident, yet it's far easier than carpet to winch the boat onto. The stuff will never rot or shred. I don't know how well it would work with a fiberglass boat, but with an aluminum boat it's truly excellent. Check into it.
Shellback 11-30-2009, 08:41 AM Thanks, I bought some bunk glide on's. Can't remember the manufacturer off the top of my head. These cover the tops, sides and ends. I'm planning to use pressure treated wood bunks. I figure the plastic covers will eliminate any corrosive action between the aluminum boat and the pressure treated bunks.
perchjerker 12-02-2009, 02:15 PM Thanks, I bought some bunk glide on's. Can't remember the manufacturer off the top of my head. These cover the tops, sides and ends. I'm planning to use pressure treated wood bunks. I figure the plastic covers will eliminate any corrosive action between the aluminum boat and the pressure treated bunks.
I would be careful with that Ron. The chemicals in the wood could leach out when the bunks are wet and get to the hull. You know how water is, it will find its way somehow and if its carrying the chemicals in the wood, that wont be a good situation
Shellback 12-02-2009, 03:37 PM Brian, I do plan to keep an eye on it, rather than install them and forget about it.
perchjerker 12-02-2009, 04:25 PM Brian, I do plan to keep an eye on it, rather than install them and forget about it.
but by the time you notice that the the hull is coroding from it, then its too late
why risk it?
I would just use oak or something
Shellback 12-03-2009, 05:57 AM Yea, I think I'll bypass the P/T wood. I can get rough sawn cypress from a mill near me, but it would have to be planed and cut to size and I don't have access to any woodworking machines. Well, it's not like I'm doing it tomorrow anyhow, got till spring.
jokerjim 12-03-2009, 07:35 AM How about that plastic stuff they use on decks ?
The "old" chromated copper arsenate (CCA) pressure treated wood, if it hasn't been banned in your state, won't react won't mess up your aluminum. Read the tags stapled to the end of the lumber. If they say the wood is alkaline copper quaternary (ACQ) or copper azole (CA-B or CA-C) make sure they won't come into contact with your boat hull and all fasteners are heavily galvanized. This really shouldn't be a problem with corrosion on your boat anyhow because you are adding plastic glide-on's.
Oak rots almost as fast as pine. Ceder and redwood are readily available and work as well as cyrpress. No untreated wood will come close to lasting as long as pressure teated lumber though.
Don't go with the Trex-type plastified deck wood unless you the bunks have supports every 18" or so. The stuff warps horribly over time.
perchjerker 12-03-2009, 09:16 AM even if he puts plastic caps over the wood he still has to fasten it to the bunks with screws or nails and that will create holes in the plastic caps that will allow the chemical to leach through. my oak bunks are 8 years old and are fine.
ckraning 12-03-2009, 03:26 PM As far as oak goes it makes a difference to whether you use red oak or white oak. The pores in Red oak allow the water to be drawn deep into to wood, whereas white oak doesn't. You can easily blow thru a piece of crosscut red oak 2 inches long. A crosscut piece of white oak a 1/4 inch thick does not allow the same. If you research on the internet white oak will show up as having moderate root resitance were red oak will be poor.
A lot of the Plastic decking matrials have poor stuctural strength and would not work well on long bunks only supported in two locations. Check with the manufacturer of such material for span strengths.
There reason most bunks rot fairly quickly is because the are carpet covered and the moisture does not dry out quickly between the carpet and the wood. The plastic guide strips might eliminate that issue.
fisnnutt 12-23-2009, 06:57 AM By all means use the plastic glides on the bunks. Countersink the screws and seal them with a top quality silicone caulk.
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