trailer bunks..........

[.NOBODY]

From time to time, ski boat owners need to replace their bunks.

So, I thought I'd snap some photo's of what quality bunks looks like.

What we have here is 4 X 6 center cut cypress with 20 oz. carpet secured using SS screws and washers.

Bunk fasteners are are SS, through bolted and countersunk. (thread locking nuts)

This trailer is 4 years old.

[Ewok]

What kind of washers did you use between the SS hardware and the aluminum bunk supports to prevent the galvanic corrosion? Got any pics of the bunks before the carpet? What about using wood plugs on top of the counter sunk bolts and carpet on top of that for extra protection in case a bolt starts to back out? I doubt that would happen but just thinking out loud.

[Duncan]

Whoah. 4x6 cypress. That is thick and hardy stuff!

[25cents]

Did the trailer come with 4X6? The boat would sit higher so what other adjustments did you need to make.

[Ewok]

That's a custom made aluminum trailer he had made to replace the stock trailer, he uses his boat in salt water. I like the thick pieces of cypress, when I have to re-do my bunks I'll use cypress as well. Maybe all the guys with Z1's and prop clearance issues should replace their bunks with 4X6, I'll give them the clearence they need without the spacers.

[.NOBODY]

That's a custom made aluminum trailer he had made to replace the stock trailer, he uses his boat in salt water. I like the thick pieces of cypress, when I have to re-do my bunks I'll use cypress as well. Maybe all the guys with Z1's and prop clearance issues should replace their bunks with 4X6, I'll give them the clearance they need without the spacers.

That's a really good idea Ewok.

Box store lumber is horrible these days. (Well, at least here in Florida it s) They call it #2 but it's really #3. Then comes marine grade lumber, which is truly #2 and treated with CCA (copper chromated arsenate).

But center cut cypress is definitely the way to go.

I'm throwing it out there just to plant ideas for others that need to replace their bunks.

A lot of times I see the question, "can I use composite deck". Of course the answer is NO, but the question comes by because people don't want to deal with bunk replacement every 3 year or 4 years.

Just stay away from box store(lowes or HD) lumber and you'll be happy.

But as Ewok pointed out.........4 X 6 could be the cure for those that need prop clearance.

Since it's rare to find bunks this thick, it just helps to see the possibilities outside of the norm.

[.NOBODY]

The galvanic corrosion is minimal, but there is a small thin plastic washer between the nut and the base metal, and the bolt head & base metal.

Aside from that, the corrosion is minimal with 304 stainless hardware as shown in this picture.

As for the other question...........the nuts are nylon locking. They won't back out. Sometimes called Nyloc. This is better than a lock washer.

It would suck to have a bolt rip the gel coat on the boat bottom....and this has happened before on other trailers I owned. The cause always came from junk wood on it's last leg.

[chpthril]

Why cant composite be used?

[Ewok]

I think composite can be used, just not the thin 2x4 planks you can find at home depot. I would love to use composite and maybe not even need carpet but I haven't seen it in thicker sections that could hold the weight of the boat without additional bracing.

[.NOBODY]

Why cant composite be used?

We give you permission to use composite, but nobody else should.

[chpthril]

I think composite can be used, just not the thin 2x4 planks you can find at home depot. I would love to use composite and maybe not even need carpet but I haven't seen it in thicker sections that could hold the weight of the boat without additional bracing.

i can easily see it being an issue finding an appropriate size plank in composite for all boats, but lets pretend we can get composite in all the same sizes as natural wood. im just curious whats wrong with the material.

[ericinmich]

i can easily see it being an issue finding an appropriate size plank in composite for all boats, but lets pretend we can get composite in all the same sizes as natural wood. im just curious whats wrong with the material.

My knowledge of composites is from doing a deck with trex. Mostly 5/4th by 6 but some 2x4 and 4x4. Trex is more flexible and wouldn't support the boat much in between where it's fastened to structure. I would be worried that the fiberglass hull would flex to match the support (or lack of it).

[chpthril]

Ok, so composite is not as load bearing as wood of the same x by x by x. That would make sense. But, if you did a custom made trailer that had an additional support under each bunk that split the span, then a composite would be fine

[ericinmich]

Ok, so composite is not as load bearing as wood of the same x by x by x. That would make sense. But, if you did a custom made trailer that had an additional support under each bunk that split the span, then a composite would be fine

I think there was some specs on the trek but from what I remember I would suggest at least twice as many supports. Another option would be a 2x6 wood covered by 2x6 trex.

[.NOBODY]

I think there was some specs on the trek but from what I remember I would suggest at least twice as many supports. Another option would be a 2x6 wood covered by 2x6 trex.

And we circle back to 4 X 6 center cut cypress.