Galvanized Frame question (1 Viewer)

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I'm mid-resto on my '77 FJ40 and the frame is fully prepped and ready for finish. I'm looking to have it galvanized and then painted for longevity's sake because I don't want to ever worry about rust on it again.

I called a couple of galvanizers in the local Houston area and so far, no one will do vehicle frames. When I asked why, they said the liability was too great. Apparently they say galvanizing a frame can cause the frame steel to become brittle...

Anyone ever heard of this? To those who've had their frames galvanized, what's your take?
 
I have never heard that the galvanizing process could damage steel. They galvanize trailer frames everyday for boats and utility purposes. I have had no issues with my frame and fellow mudder @roma042987 galvanized his frame about 2 years before I had mine done. He has thousands of miles on his rig both on and off road with no issues. I honestly don't know where some people get their information from (I am referencing the galvanizers here not the OP).
 
I'm mid-resto on my '77 FJ40 and the frame is fully prepped and ready for finish. I'm looking to have it galvanized and then painted for longevity's sake because I don't want to ever worry about rust on it again.

I called a couple of galvanizers in the local Houston area and so far, no one will do vehicle frames. When I asked why, they said the liability was too great. Apparently they say galvanizing a frame can cause the frame steel to become brittle...

Anyone ever heard of this? To those who've had their frames galvanized, what's your take?

I did a little research on the topic as mine will be getting galnavized soon. What I found didn’t bother me. I did find a consensus that hydrogen embrittlement could be an issue with 150ksi+ steels, and that galvanizing (or rather the heat of the process) could accelerate strain age embrittlement due to cold working. There was also a paper I ran across a paper detailing some failures within the heat affected zone of mig welds on 50ksi Steel. I don’t know how exactly our frames were produced or what the exact steel composition is - but the recommendations from ASTM to minimize the chances of embrittlement wouldn’t seem applicable to what went into making an FJ40 frame.
But then again I’m not a professional galvanized or metallurgical engineer...

There’s a bunch of info out there from
AISC, ASTM and AGA.

Hopefully the local places to me don’t give me the same answer as yours did! Otherwise it will be a good soaking in chassis saver instead I suppose.
 
Hi, Owning multiple boat trailers and dunking them in and out of water I've seen no break downs in the frames. I have seen more broken welds on non galvanized trailers . To me this would be a non issue , we all know what rust does to these frames and bodies. Most good CB towers are galvanized and these are exposed to rain and extreme wind loads , and hold up quite well. Mike
 
Land Rovers sell galvanized frames all the time.
 
I had my fj45 frame galvanized back in 94. It went through a 4 tank process. The frame is dunked and submersed.
The other cheap-o route is have it sand blasted and use a spray can of cold galvanizing. The first option is the ultimate !
 
Custom fire apparatus have an option to have a galvanized frame from one of the biggest names in the business.....
 
I did a little research on the topic as mine will be getting galnavized soon. What I found didn’t bother me. I did find a consensus that hydrogen embrittlement could be an issue with 150ksi+ steels, and that galvanizing (or rather the heat of the process) could accelerate strain age embrittlement due to cold working. There was also a paper I ran across a paper detailing some failures within the heat affected zone of mig welds on 50ksi Steel. I don’t know how exactly our frames were produced or what the exact steel composition is - but the recommendations from ASTM to minimize the chances of embrittlement wouldn’t seem applicable to what went into making an FJ40 frame.
But then again I’m not a professional galvanized or metallurgical engineer...

There’s a bunch of info out there from
AISC, ASTM and AGA.

Hopefully the local places to me don’t give me the same answer as yours did! Otherwise it will be a good soaking in chassis saver instead I suppose.
Does anyone know what grade of steel the frames are made of?

I can say with near certainty that its not anywhere close to 150ksi. In the 60s/70s I would expect to see ~36ksi steel as anything higher was very expensive to produce.
 
It can cause the frame steel to become brittle so as what will happen? Why do most road sides have galvanized guard rails? Do they galvanize them so a vehicle will shatter the "brittle" guard rail galvanized steel and fall to its death? Sounds like they are retards.
Guard rails are made of mild steel who's strength is not greatly affected by the galvanization process. High strength steels (especially older alloys) can be made brittle by heating which causes changes in the molecular structure of the steel.
 
Guard rails are made of mild steel who's strength is not greatly affected by the galvanization process. High strength steels (especially older alloys) can be made brittle by heating which causes changes in the molecular structure of the steel.
How brittle? Isn't the dip only at 800 degrees? Thats hot enough to affect the steel?
 
I would thing that welds would do the same thing only worse..
 
It can cause the frame steel to become brittle so as what will happen? Why do most road sides have galvanized guard rails? Do they galvanize them so a vehicle will shatter the "brittle" guard rail galvanized steel and fall to its death? Sounds like they are retards.

Hydrogen embrittlement is a real concern with high strength steels, but is not a concern for things like frames and guardrails.
 
How brittle? Isn't the dip only at 800 degrees? Thats hot enough to affect the steel?

It’s not that the heat directly embrittles the steel. It’s that atomic hydrogen can make its way into the steel during the process.

This is more of a concern during plating operations of high strength steels. This is why you shouldn’t plate head bolts. Sure they look pretty all zinc or cad plated, but there’s a reason why toyota didn’t plate a few bolts on these trucks.

For those of you that have plated your own parts, you’re probably familiar with the bubbles that leave the plated parts during the process. That’s hydrogen gas generated at the cathodic reaction of the process.
 
I’m considering this for my LV frame and came across the following:

Services - Industries/Services - COLORZINQ® Duplex System

I know nothing about this particular vendor, but You probably won’t beat a good duplex system for corrosion control. Duplex systems such as galvanizing plus paint have been proven to outperform the sum of their parts. For example, if the galvanizing is expected to last 30 years and the paint is expected to last 20, you can expect performance in excess of 50 years if properly applied.
 
V&S is the vendor and they have a number of locations on the eastern side of the US:

Locations

I'll see what I can find out when I contact the vendor and update this post. Spring Break is coming up and I'd like to drop off the frame and have it back in time for the warm weather.

The only concern I have is the build-up in the threaded portions of the frame. I recall a write-up that detailed this in Toyota Trails. The person used sacrificial bolts to protect the threads during the process. Some of the bolts broke during the removal process and the solution was to heat the bolt long enough to soften the zinc before extracting the bolts. Can anyone else comment on this?
 
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