Bunk lag bolts

Boilers2000

Petty Officer 1st Class
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Jun 15, 2018
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252
Are galvanized lag bolts okay to use for trailer bunks? Was going to use stainless steel, but can only find 1" or 1 1/2" and was looking for 1 1/4". 1" feels too short.

Thoughts from the experienced captains.
TIA
 

jimmbo

Supreme Mariner
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May 24, 2004
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13,446
I think the ones that hold the bunks on my trailer are about an Inch, never had an issue the 21 yrs I have owned it
 

airshot

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Jul 22, 2008
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I always used carriage bolts with the round head then nuts and washers on the bottom. Carpet keeps the heads away from your hull, had way to many lag bolts pull out or fall out but never lost a carriage bolt in my 50 plus years of towing.
 

jimmbo

Supreme Mariner
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If you decide to try the Carriage Bolt thing, make sure the Bolt Heads are Countersunk well below the top surface of the Bunk
 

airshot

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If you decide to try the Carriage Bolt thing, make sure the Bolt Heads are Countersunk well below the top surface of the Bunk
Absolutely right but if covered with carpet as most are they will be fine. I typically overtighten the nuts which draws the head well below the surface. Shoukd have mentioned that, thanks...
 

bruceb58

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Mar 5, 2006
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I just use galvanized lag bolts. Used to use carriage bolts but if the nut seizes, you will never be able to get it off without destroying the bolt....major PITA.
 

airshot

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I just use galvanized lag bolts. Used to use carriage bolts but if the nut seizes, you will never be able to get it off without destroying the bolt....major PITA.
I hear ya, when my brain is working right, I remember to smear a little anti sieze on the threads to prevent that but have forgotten on ocassion. Gues that isvwhy they make cutoff wheels.
 

bruceb58

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I hear ya, when my brain is working right, I remember to smear a little anti sieze on the threads to prevent that but have forgotten on ocassion. Gues that isvwhy they make cutoff wheels.
Yep...which is why I hate carriage bolts on bunks.
 

JASinIL2006

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Lags bolts work fine unless the bunk boards are too soft. I re-used the boards and lag bolts when I recarpeted my 1997 trailer and they still are holding strong.
 

liquidlabfx

Seaman
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May 23, 2023
Messages
58
Are galvanized lag bolts okay to use for trailer bunks? Was going to use stainless steel, but can only find 1" or 1 1/2" and was looking for 1 1/4". 1" feels too short.

Thoughts from the experienced captains.
TIA
For sure. I have these on a 30 plus year old trailer and just a little surface rust.
 

JASinIL2006

Vice Admiral
Joined
Feb 10, 2012
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5,673
If you get good galvanized lag bolts (e.g., hot dipped), you should be OK. Avoid cheapo galvanized bolts.

Or you can order stainless from McMaster-Carr:

 
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