Hi 

 

I am currently completing a set of gates ,more like doors in a way .

On previous gates I have made, I have not had them galvanized ,except for a set a few years ago 

when I got them back from being galv and painted the latches were basically stuck ,

I am thinking possibly using stainless this time to avoid this problem ,and then placing them on after 

it is galv .Any ideas ,pictures would be great .Thanks for any help 

If they were hot dip galvanized than moving parts are going to get locked up. end of discusion. if you want them galvanized you need to have all moving parts separate, and they need to be made to account for the added material build up from the hot dipping process.

 

Next time just have them do the parts separately, and assemble them after it's been dipped.

Think of the hot dip galvanising tank as being full of soft solder guaranteed to bridge all the gaps you don't want it to! So definitely assemble moving parts post process.

I found that it was so best to drill and tap for bolted fittings after it was galvanised as well. It seems to bind up even the sharpest tap if one pre-drilled and tapped.

On some projects I tried letting in a bit of stainless steel and then drilling and tapping into that in order to preserve the integrity of the zinc. But then I learned that the zinc only has to be present to fulfil it's function it does not need to seal the surface. I understand they just bolt sacrificial blocks of zinc every metre or so to deliver galvanic protection on some large steel structures.

Alan

You might want to think about using car paint and primer.  Using a good automotive primer will help and maybe a lot cheaper than hot dipped gal.  Even with primer and paint you must consider the thickness of those layers in your calculations.  Here in California, the authorities have outlawed all the really good primers and paint so you can't get them anymore.  You might have better luck in your location of Maine.  Good luck  

in the long run hot dipped is far cheaper that primer and paint. hot dip once, paint and primer every 5-10 depending on use and location.

At work we use a rust-proof paint called galvafroid, it's pretty expensive stuff but we only use it on things that we're unable to galvanise. It does the job and does it well, it might be worth looking into. Otherwise, as others have suggested, assemble after galvanising, preferably with bolts and not welding!

Good luck.

In days of old pre H&S problems you could use lead coated rivets to attach loose bits, or oxy acet and a zinc bar to coat any of the untreated areas.