Thread: 2A SWB in the shed

The best way if you are going for an "as new" final product is remove, regal and replace IMO. Not a difficult job, expensive though. The joint between the paint and the capping never comes out quite right if you don't.
Great job so far, keep going and keep updates coming.
Regards

If you do remove all the trim to be re-galved try and find a galvaniser with a centrifugal, (or spin), galvanising process. This will help prevent getting blobs/uneven coating.

Cheers,

Edit: Disregard this and read the next post!

Tim if the galvanizer hangs the job correct there should only be a drip on one corner. They usually try to hang off on cornor so hangs on an angle , you get a better looking galv finish when , you get like a shiney leaf print . With centrifuge it spins the excess zinc off & usually comes out a dull finish.
All so you are more likely to loose items in the centrifuge as they mix lots of other jobes in with yours & after spinning they open the bottom of the basket & it all goese into a quench tank & is then retrieved from the tank then a guy who has never seen your items before sorts all the different jobs .
They usually dont do larger items in the centrifuge. When I was in business I was at the galvanizers every day we were putting 20 ton or more a day through the galvanizers. I used to wire& hang club members LR cappings & take them for dipping , I would tell the galvanizers not to cut the job off the wire & not to dress the job as there was less chance of loosing anything & also they would dress with an air grinder & grind through the galv then put cold galv on with a 1" brush. The best way to dress is with a bog file or flat file. If you do need to touch with cold galv to get the colsest colour finish to galv is to use a pressure pack can of spray aluminum colour , spray a coat over the cold galv , leave it for a couple of minuts then litely wipe it with a rag.
They add a chemical to the quench water to prevent white rust this causes the galv to have a yellow / green tinge which will fade after a few days in the sun.
That is my experance with galvanizing over a 35 year period.

PS we also used to repair & also make dipping baskets for the galvanizers , I have seen what happens when they let go a lot of product gets damaged .
I had all the galv dipped not centrifused 29 years ago & most of it still has the leaf print but has dulled a little.

Thanks for all the info, I am a bit worried about bits being lost, (the electroplater has managed to misplace a couple of parts). I've got a few spare bits that I might "test with", as so far I haven't gotten any decent reviews from anyone regarding galvanisers in Perth :/

Cheers,

PS Sorry about the thread hijack!!

Thanks Gents, and I'll take 1950Landys' 35 years of experience and find a galvaniser in ACT......will be my winter project:-)

Col.

G'day All,

I use Silver Zinc Cold Galvanising in a spray can made by Wholesale Chemical Company | Anti Rust Coatings | Silver Zinc | Liquid Zinc | Black Zinc | Anti Seize | Metal Working Compound.
for most steel work I do here in Sydney. Galvanisers charge a minimum order of over $100 in Sydney now.

Email Wholesale Chemical Company and they will advise where to buy in your location.

Chris

Originally Posted by TimNZ

Thanks for all the info, I am a bit worried about bits being lost, (the electroplater has managed to misplace a couple of parts). I've got a few spare bits that I might "test with", as so far I haven't gotten any decent reviews from anyone regarding galvanisers in Perth :/

Cheers,

PS Sorry about the thread hijack!!

Tim,
I will go to my old company & take some photo's of Dipped & centrifuged galv so you can compare the difference. Galvanizing is strange, depending on the silicon content of the steel you will get a different finish . Also you will get a thicker build up of galv on areas that have been welded , so if you weld up a hole than grind it back smooth you will be able to see were the hole was because after galv that area will be raised.

If you sand blast the steel you will get a different finish to steel that has not been blasted, it tends not to be smooth but textured.

Galvanizes always try to hang jobs from one corner so the excess zinc can run the the opposite corner that they only need dress that corner.

They will charge you for stripping the old galv off as it dilutes there acid , but you get a better finish when they strip it as opposed to sand blasting the galv off. If there acid is new they do not like stripping off galv so it may tale a little longer to get the job done so they can do it in older acid. It is also best to try to get any paint on the capping's off using paint stripper as it may not come off in there caustic Barth if the caustic is getting old & they may tell you it needs blasting or charge you to remove it.
They may also tell you they need to drill extra holes in the job to prevent air pockets or better drainage. If it air pockets the steel won't pickle properly & the galv wont stick & if it dose not drain you will be charged for excess zinc that you do not need .

Galvanizes charge on the total weight of the item after galvanizing They do not weigh the job before & after , so if the job weighs 100kh after galv & they charge $2 a kg than the cost will be $200 plus stripping charge which used to be twice the cost of galv. I am not sure of the cost of galv now , it is 7 years since I sold my business & retired.

It is best to take as much to the galvanizes as possible as most have a minimum charge .

Hope this gives you a better understanding of galvanizing

PS , almost forgot all pipe needs to be vented at top & have a large drain hole at the bottom. If there is ait traped in side the pipe can explode in the zinc blowing a large quanity of molten zinc out of the pot. In some cases were there are two flat surfaces welded together with a sealed fully sealed weld they will require holes driled into one od the plate because the expanding air can tare the two plates apart rendering your job useless.
In most cases LR fittings will not require any extra holes as they have been done before but there are a couple of items that will require extra holes. . The hinges & latches on seat boxes on S1's hsve alum pins these will need to be removed before sending for galv other wise you will only have one half when they come back. This I learnt from experience
Threads can be cleaned of exces zinc by heating with blow torch & wire brushing .& you can buy zinc sticks from welding sippliers for repairing galv. Looks like stick of solder & is used same as tining with solder were you heat the area & apply zinc & work it in with a wire brush .

G'day All,

Excellent thread on Galvanizing by 1950landy.

I have used Mechanical Galvanising by this company in Sydney:

Profile

The process uses chemical and mechanical methods to zinc coat (Galvanise) metal components and in particular screws, bolts and nuts.

I had a tow-bar drop plate and fittings zinc coated by this company in 2014. The results were excellent however, the inside of the tow-ball fitting missed out on the mechanical part of the process.
The down side was the minimum charge of $100.

Chris