Thread: galvanizing a whole trailer

Originally Posted by ajm_bris

folks, any ideas on where and how much it would cost to get my trailer galvanized in brisbane? its been a year and its not looking as pretty as it did when purchased

I assume industrial galvanisers would be able to do that, but do you really want to completely strip your trailer to have it galvanised? Was it not gal when you bought it? If it wasn't, sell it and buy a gal one… or paint. I'd be using a zinc phosphate primer with a good topcoat of paint.

Queensland | Galvanizers Association of Australia should show who can do what

Can't help you with the rate, but I think for hot dip galvanizing they charge by the weight of the article being dipped. And if the are any fully enclosed hollow sections (eg RHS or SHS) they will what holes drilled in them so it doesn't explode (expansion) in the hot molten bath

Originally Posted by richmond68

I assume industrial galvanisers would be able to do that, but do you really want to completely strip your trailer to have it galvanised? Was it not gal when you bought it? If it wasn't, sell it and buy a gal one… or paint. I'd be using a zinc phosphate primer with a good topcoat of paint.

Queensland | Galvanizers Association of Australia should show who can do what

thanks for the link. as for the advice: i am hoping getting it dipped will work out cheaper than the potential loss on resale added to the overall higher price of the gal trailers similar to my non gal one. and yes, i should have got gal to begin with.

Couple of things to be mindful of;

As Rod has said, any hollow sections will require at least a 1/2" hole in both ends of any sealed RHS piece. If you don't do it, the galvanizing place will, for at least $1 a hole.

If the flat panels (floor, sides, gates) are only 1.6mm, and many trailers are, they will buckle with the heat of the bath.

Any fine tolerance fit pieces like tailgate hinges and catches can tend to clag up when a coat of Gal is added. So if you're thinking of getting it done, maybe look at modifying those bits to be removeable and have them all done separately, or even zinc plated, and reassemble later.

Originally Posted by Yonnee

If the flat panels (floor, sides, gates) are only 1.6mm, and many trailers are, they will buckle with the heat of the bath.

I can testify to that. I had exactly that happen with a small truck body. The sides and tailgate were ok because I had folded a profile into them so there was somewhere for the metal to go when it expanded, but the floor was a disaster. I should have welded a gal sheet in after.

Regards
Paul

Originally Posted by ajm_bris

folks, any ideas on where and how much it would cost to get my trailer galvanized in brisbane? its been a year and its not looking as pretty as it did when purchased

In short, don't do it.
It will cost a fortune.
Depending on the paint used already, you will, (almost definitely), have to sandblast it and galvanising is not cheap.
There are so many great paints available, such as 2 pack etc, that are as hard as a goats forhead and will give great results.
Galvanising would be my last choice for anything but a boat trailer to be honest.

Last I heard it would cost around $700 for a 6x4 box trailer. The trailer being painted already isn't a issue as they acid dip everything first to remove any paint, rust ect.

Originally Posted by Rat1314

Last I heard it would cost around $700 for a 6x4 box trailer. The trailer being painted already isn't a issue as they acid dip everything first to remove any paint, rust ect.

Actually it is quite an issue. Many paints are not dissolved and removed by the pre galvanising bath. I have had a lot of galvanising done in the past and can tell you that even the blue undercoat on some rhs is not removed. Lap joints such as where a floor sheet passes over a crossmember are another area of potential consternation when galvanising, (one particular job from my past stipulated that a 1mm gap be left between two rhs members that lapped together for this reason). Many galvanisers also baulk at galvanising heavily rusted items without their prior sandblasting/ mechanical cleaning.
The main thrust of what I am saying is that items not originally intended for galvanising present a range of challenges and extra costs if you try to galvanise them at a latter stage.
Galvanising protects steel really well in some environments, but not others - for example, when building underground mining equipment, we found that galvanising was next to useless, but a thick coat of GP equipment enamel worked really well. Not that I expect this trailer will spend too much time in the subterranean world