How Do I? How resilient is galvanising ?

[jimbobhorton]

Basically, after trying to keep paint based maintenance to a minimum, so was wondering how resilient bare galvanising is if left un covered? Saves the bind of painting and repainting after you chip the paint work etc.

In the fullness of time I will probably get galvanised rock sliders, bumper, turrets etc. I have heard of people not bothering to paing a fully galvanised chassis, I take it the same goes for other bits !?!

Is galvafroid the same, ie can be left bare, or is it a lot less resilient than hot dipped. Was thinking about doing my axels and arms etc. with that. Won't look as good as shiny black, but am prepared to lose a bit on looks if it means doing the job less frequently.

Cheers

Jim

 

[alex]

Proper Hot dip galvanise is the best treatment of steel you can get. Galvafroid is nowhere near as effective and is only a primer. There is a limit to what you can treat as it can distort thinner metal under 2mm. Also box sections need to have holes drilled in them to let gas escape and liquid zinc go in and out during dipping.

For thinner stuff there is a method of hot sprayed zinc which is reasonably good but you may find that difficult to get small stuff done. Proper powder coating is good for small stuff and there are plenty people doing it Works out cheaper than buying paint and is far more durable.
Alex

 

[bvudzichena]

I used to have a 1962 IIA with a galv chassis.

The truck was supplied new with said chassis. I bought the truck in 2002 when it was 40 years old and sold it in 2005. There wasn't a spot of rust anywhere on that chassis.

To add to what Alex has said about hot dipping. I saw the process for the first time last week and I've concluded that it's the only way to go.

Don't be scared when it comes to drilling holes into box sections. The galv needs to be able to run out. If you don't have enough holes you are going to end up with uneven galv buildup inside the box section.

 

[jimbobhorton]

Cheers for the advice.

Back to the drawing board it is.

 

[Daz800]

drill holes in box section ( and any closed box or tube)about 12mm from any welds and use a 8mm drill. Drill 1 hole each end.
The hole is so galv can vent into the box section and also to stop the tube/ box section from splitting due to pressure.

If the galvers notice any problems with drain holes etc they wont do it.

We have a lot of our work galved so if you need any advice then i will help if i can.

To have items galved it dont matter if it goes to them rusty as long as its in good/ solid condition.

Most galvers charge by the tonne for large items which can be between £250 - £300. You may be lucky to find one that will do a one off price.

Be carefull if they charge low prices as they will "quick dip" which is a waste of money.. in other words, it seen the galve not bathed in it.

Some galvers charge for "fletters" which means they linnish all excess galve off. Do it yourself as it just a quick lick with a grade 60 linnish pad and remenber to retap any threads.

Darryl

 

[bvudzichena]

Darryl has raised the very important issue of quick dipping.

The piece of metal on the left of this photo didn't spend enough time in the tank. Compare it with the bracket on the right that stayed in the tank at 445 degrees celcius until it started bubbling.

I suspect we'll see rust on the piece on the left after it's been to the seaside once. The one on the right will last for years and years.

 

[Daz800]

Looking at the above photo i would say they have been plated not galved.

Looks like zinc and clear plate.

Darryl

 

[bvudzichena]

Looking at the above photo i would say they have been plated not galved.

Looks like zinc and clear plate.

Darryl

I had the same fight with the people who did it.

Compare what's above with these that I watched being dipped.

 

[Daz800]

i edited the last post i did because i had a good look at that photo of the wheels.

They look like they been galved.

Darryl

 

[bvudzichena]

They look like they been galved.

There is no doubt in my mind that they got the proper treatment.

First, they were sandblasted, then they went into an acid bath, followed by two immersions in water, then into the flux and then into the big tank of zinc.

This company uses about two two tonnes of zinc a day (£4750 worth of zinc). They are a huge galvanising outfit.

The molten zinc stays at about 445 degrees celcius and the items being hot dipped remain in the tank until the zinc starts bubbling. There's a lot of hissing, gas and nastyness when the items go into the tank, but they then settle down and when they are ready, they start bubbling. It's only once the operator sees the second set of bubbles that he gets the gantry over to lift the tray of items out of the tank.

The items then get cooled down (twice) in a water tank and then go for hand finishing. Here some men attack the items with oxy-acetelene torches and wire brushes - removing all the excess zinc.

It's worth asking the plant management nicely and getting the 50p tour

 

[AndyK]

Hiya,
just to add to the discussion when I repainted my 101" I took the galvanised cappings off the removable parts (many!!!!) so I could do a decent job of repainting them (which ended up rubbish!) I didn't know of any local galvanisers so I just rubbed the cappings down and spray painted them with a generic "Galvanising Spray" from a spray can and was plesantly surprised. I had to redo the paint job but the spray galvanising was still looking good when I sold my 101" seven years later.

The first picture was freshly painted, second just looks good!, the third was just before I sadly sold Barney to buy Bluey the 110

Andy