new trailer bunks

[hart]

Well now that I have new tires it's time to repair the bunks since I broke one off a badly corroded bolt the same weekend I cut the tire. And a couple more are in poor shape. I'm hoping to get it done this weekend with all new bunks, carpet, and stainless bolts.

I picked up several carpet samples and I'm going to test them with water and sand to see how each holds water and grit before I pick one. Our local Lowe's stocks marine carpet including 2 kinds meant for bunks and it's cheaper than what I've found at the boat stores or on Ebay so I'll probably go with one from there.

I'm trying to figure out the curved bunk in these photos - not the one held on with rope, the one farther aft. Is it original to the trailer? I had assumed so until I noticed that it's bolted on instead of welded so now I'm not sure.





There are 2 more shots here, and you can get larger versions if you want to see it closer.

The rest are just 2 x 4's so they are easy but this one seems curved and a non-standard size.. I need to measure more closely but I'm thinking I could get a 2x6 or 2x8 and use the original as a pattern and cut to shape. I'm worried about the bottom of the "V" though - seems like it's pretty flimsy since that's where this one failed. Anybody have a better idea?

Also, assuming it's original, is it supposed to touch the bottom of the boat once loaded? It hasn't since I bought it so I'm not sure if it's supposed to or if it's more of a guide for loading and unloading purposes.

And since the rust is so obvious in the picture - I'd better mention painting is on the agenda too since the boat will be in a marina for about a week anyway.

[parrothead]

We have an , but I have seen several :macx:s on their trailers in dry storage at our previous marina, and I'm certain that the curved bunk you have was fabricated and bolted on by a Previous Owner. It looks like it was intended to help center the bow during loading. It isn't needed as a weight-bearing surface.

[K9Kampers]

Hart - as parrothead suggests, the bunk in question is non-standard for an trailer. Mine doesn't have one and I've not seen it on others.

[hart]

Thanks guys. There are several other additions to the trailer too. That helps a lot. Knowing it doesn't need to carry the load on land makes me feel better about my construction idea. It quit raining so I went for a closer look. I think maybe that bunk is made from rough cut lumber as it's thicker than a standard 2 by. I'll probably replace with a standard pressure treated instead.

[K9Kampers]

It may have been a mod to support the bow while loading at haul out, so the bow doesn't CHUNK on on the forward V support. Some have installed a roller to prevent that.

[hart]

I've read about the roller. Perhaps this extra bunk does serve a similar function since I've never noticed a CHUNK while loading. Thinking about how the boat moves when I'm loading it I think perhaps it does help guide on to the bow also. Once I get the bow past my 2nd set of "goal posts" (also a P.O. mod that I love) the boat does sort of self steer into the bow chock.

I love the previous owner more and more. Man he did some cool mods.

[Chinook]

I rebuilt my trailer bunks a couple years ago, when I repainted the trailer. I couldn't get the old ones off without shearing off the bolts, which were badly rusted. The wood inside the carpet strips was cracked and showing signs of deterioration as well. I made my new ones with that plastic composition material that you see on some park benches and outdoor deck construction. It should never deteriorate, and it also cuts easily with a power saw, and also holds staples well. I took dimensions from the old boards, and stapled new outdoor carpeting to them. For attachment I used stainless bolts with spurs on the head. I counter sunk a hole, with a forstner bit, into the new boards, and then tapped the bolts into place. I then stapled the carpeting over the board and bolted them down. With this arrangement, I should be able to undo the nuts from beneath, without the bolt spinning around under the carpet. So far they are holding up well.

[hart]

That's that Trex stuff? Replace it once and your done. Not a bad idea at all.

I've used pressure treated pine on my boats in the past with decent results. I like to get the greenest wood I can find so the boards will bend a bit and form to the shape of the hull better. That doesn't really seem to be an issue with how the Mac trailer is laid out though since the bunks run crossways.

[dvideohd]

Thanks to kind advice from here and elsewhere, I am replacing the bunks on my trainer.. the Pressure Treated wood has a large piece litterally rotted off - and the carpet hid that...

Replaicing with Pressure Treated Pine and plastic from these folks... surfixinc.com/surfix_trailer_bunkslides.html

can work on trailer paint as well..... starting here..


--jr

[hart]

The weather is perfect for sailing so I'm finally working on the trailer instead. I'll post some pics later as I go.

[hart]

Finished up the trailer refurb today. Finally. A few weather delays really slowed me down. But it's all done. I've got before pics and I can take some after ones if anyone wants to see. Doesn't show much, just a dirty trailer with black and gray carpet and now a clean trailer with black carpet. I didn't get any along the way though since my hands were usually covered in rust, paint, or grease and I didn't want to touch the camera.

A few observations:

monel staples are really expensive.
pressure treated 2x4's are very forgiving and easy to work with
stainless hardware from the big box stores sucks. Buy it from a reputable marine source instead


That's it I guess. We're off to go sail and load the boat back on the trailer and hope it still fits.

[hart]

Okay, well I got rained out of work today so it's picture time.

Here's the trailer before I started working on it:



As you can see some of the bunks have rotted off and had to be temporarily tied with rope. The rust looked worse in person than it does in this picture. I ended up not using the Naval Jelly all that much and relied on sanding, scraping, and a wire brush. Where I got down to bare metal received primer before paint. I wish I had gotten a picture of that. Over half the trailer was orange. It was hideous!


Here's what the saltwater does to your bolts:



Some of this was stainless but I couldn't tell you what grade. Some was galavanized and some was regular stuff. I replaced it all with stainless from my local ships store.

And here's the finished job:



We secured the wood for the factory bunks first and then carpeted them so there are no holes in the carpet. The additional bunks did require a little more work and finesse. As you can see some hardware does show on some of them.

There are a few more pictures in my Flickr account that show some of the rusted places in more detail.

All of the "non" factory bunks were created by the previous owner so it was easy for me to cut new ones from the old stock. I have a better understanding of exactly what they do now that I've rebuilt them too. I'm glad they're there. Loading is so easy I can't imagine not having them.

After loading the boat yesterday I'm pleased with how the new "curved" bunk up near the bow worked out. I had to guess on the curvature since the old one was broken. The boat fits it pretty well. It does help guide the boat as we discussed above but it also does provide some extra support on the trailer. I made the new one out of a single piece of pressure treated 2 x 12. Hopefully it will hold up better than the old one.


Loading the boat yesterday was considerably easier than it has been. It slides much better on the new carpet and I didn't hear any "groans" or "pops" like I did with the old bunks. All in all it was an easy but time consuming project.

Unfortunately 7 1/2 days in the marina was long enough for thousands of baby barnacles to start growing on the bottom of the boat. Thank goodness we got home in time for me to scrape them all off before it got dark yesterday. Little tip: when they are still wet and alive they come off easily (I used my fingernails and a rigid plastic squeegee looking thing) but if you let them dry they are like concrete.

[Piddle and Futz]

Thanks for your description and many photos, hart.

I noticed some rotting on one of my bunk boards at last launching... and had that same board skew loose when recovering the boat.

I'm going to prep some pressure treated 2x4s (measure and cut lengths, then staple carpet in place) and install them next time I have the boat afloat. Not quite sure of the corrosion situation with the fasteners, so will pick up some extras.

Would love to pre-drill the boards and recess carriage bolts beneath the carpet, but I'm not confident that the bolt locations would be exact and consistent from trailer measurements. Figure I can countersink them on the spot so at least they don't protrude and scratch up the bottom.