Mail order small object galvanising

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Avocet

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Does anyone know of anywhere that I can post small objects for galvanising? My local galvanisers won't get out of bed for less than 100kg and I have a steel fabrication about 2-3 feet long x about 6" wide and deep that only weighs a few kg.
 
There are no "local" galvanizers in Cumbria. Your nearest are: Newcastle, Liverpool, Leeds, Manchester. In addition, some run depot style operations from Whitehaven, Carlisle and a few other places.
As Pyrojames said, put your order with that of a steel fabricator or a manufacturer and share his pricing.
Paying a minimum order charge can bring an effective price per kg of £2-3. A medium sized steel fabricator will be paying about £0.40/kg.
I had a good example of this recently. (I'm a galvanizer as well as an anchor manufacturer though 2 seperate companies and commercial rates between them). Someone wanted an anchor re-galvanized. He'd have paid minimum order charge or £100 for his 13kg anchor. £7/kg. By adding his anchor with a batch of new manufactured anchors where the order was for loads of anchors, and not at minimum order charges, the charge for just his anchor was £5.20.
So seek out a friendly fabricator. If you don't know any email me and I'll help. And if you smile really nicely, I could collect it, as I'm in Cumbria on Monday, and a galvanizing plant Tuesday...
 
MM5AHO said:
There are no "local" galvanizers in Cumbria. Your nearest are: Newcastle, Liverpool, Leeds, Manchester. In addition, some run depot style operations from Whitehaven, Carlisle and a few other places.
As Pyrojames said, put your order with that of a steel fabricator or a manufacturer and share his pricing.
Paying a minimum order charge can bring an effective price per kg of £2-3. A medium sized steel fabricator will be paying about £0.40/kg.
I had a good example of this recently. (I'm a galvanizer as well as an anchor manufacturer though 2 seperate companies and commercial rates between them). Someone wanted an anchor re-galvanized. He'd have paid minimum order charge or £100 for his 13kg anchor. £7/kg. By adding his anchor with a batch of new manufactured anchors where the order was for loads of anchors, and not at minimum order charges, the charge for just his anchor was £5.20.
So seek out a friendly fabricator. If you don't know any email me and I'll help. And if you smile really nicely, I could collect it, as I'm in Cumbria on Monday, and a galvanizing plant Tuesday...
Click to expand...

Thanks ever so much! That's very kind indeed! Unfortunately, I won't have it ready in time. I was just "getting my ducks in a row" for a project. It's the rear crossmember for my car, a thin steel pressing (16 or 18 SWG, haven't actually measured it yet) with a closing plate spot-welded to it and a couple of bushes welded through it. I need to drill out the spot welds and replace the closing plate, which is a bit rotten, and then get rid of whatever paint / rust is on it now before galvanising. However, if the offer still stands at some future date, could I PM you when ready?
 
Yes, do that. But here's a few tips in preparation for galvanizing.
Rust: leave it unless its so bad that you can pull 1p sized flakes off with your fingernail. The pretreatment part of the galvanizing process removes rust. So if it's not so severe that you can't pick it off, leave it on.
Paint. Galvanizers nightmare! It acts as a masking for galvanizing in effect by preventing the pretreatment from working. The pretreatment doesn't normally take off paint, so the steel that's covered with paint doesn't get the pretreatment and so doesn't get galvanized.
Galavanizing is an alloying reaction, not just a coating going over a surface. The alloying reaction only happens where chemically clean steel is exposed to the zinc. If you dip a dirty piece of steel in molten zinc, all you get is a hot dirty piece of steel.
Holes: Perhaps the least understood aspect of our business. Any cavity needs a way for air to escape (vent) and another way for liquids to enter and fill it. Steel is only slightly more dense that zinc, so any air trapped inside, underneath etc gives buoyancy. If it floats, it's not submerged. If not submerged, then not galvanized. All of this must happen in the orientation that the item was suspended in on a crane (perhaps on a jig under a crane). So a cavity needs a vent hole and a drain hole, at the highest and lowest points (in that orientation). Minimum hole diameter is 7mm, but consider the volume that has to be flooded in and evacuated. 1m3 cavity won't drain fast through a 7mm hole, and the quality is largely dependent on the speed that an item can be submerged and retreieved.
Suspension. All items to be galvanized need to be suspended, from a crane, perhaps with others. This is done with wire tied on, through a hole, a lug or anywhere a good purchase can be obtained. If you had say a flat plate, with no bolt holes, no brackets, nothing. It could not be processed. Easiest is often to drill a hole through which to thread the wire.
 
MM5AHO said:
Yes, do that. But here's a few tips in preparation for galvanizing.
Click to expand...


Just to add to Geoff's comments.

I've had a number of painted items galvanised. I used paint stripper, its easiest if you are reliant on doing it at home. Some paint is not paint but powder coating and I have had to apply multiple coats, 6 coats! It does work and you need patience and a decent scrub with a harsh wire brush. Use heavy duty rubber gloves.

Jonathan
 
MM5AHO said:
Yes, do that. But here's a few tips in preparation for galvanizing.
Rust: leave it unless its so bad that you can pull 1p sized flakes off with your fingernail. The pretreatment part of the galvanizing process removes rust. So if it's not so severe that you can't pick it off, leave it on.
Paint. Galvanizers nightmare! It acts as a masking for galvanizing in effect by preventing the pretreatment from working. The pretreatment doesn't normally take off paint, so the steel that's covered with paint doesn't get the pretreatment and so doesn't get galvanized.
Galavanizing is an alloying reaction, not just a coating going over a surface. The alloying reaction only happens where chemically clean steel is exposed to the zinc. If you dip a dirty piece of steel in molten zinc, all you get is a hot dirty piece of steel.
Holes: Perhaps the least understood aspect of our business. Any cavity needs a way for air to escape (vent) and another way for liquids to enter and fill it. Steel is only slightly more dense that zinc, so any air trapped inside, underneath etc gives buoyancy. If it floats, it's not submerged. If not submerged, then not galvanized. All of this must happen in the orientation that the item was suspended in on a crane (perhaps on a jig under a crane). So a cavity needs a vent hole and a drain hole, at the highest and lowest points (in that orientation). Minimum hole diameter is 7mm, but consider the volume that has to be flooded in and evacuated. 1m3 cavity won't drain fast through a 7mm hole, and the quality is largely dependent on the speed that an item can be submerged and retreieved.
Suspension. All items to be galvanized need to be suspended, from a crane, perhaps with others. This is done with wire tied on, through a hole, a lug or anywhere a good purchase can be obtained. If you had say a flat plate, with no bolt holes, no brackets, nothing. It could not be processed. Easiest is often to drill a hole through which to thread the wire.
Click to expand...

OK, thanks for that. No problems with draining, air entrapment or floating. It's an open channel section with a closing plate but the closing plate has huge holes in it and doesn't extend to the ends anyway. It's also well-supplied with holes to hang it from because it bolts to the car. I can live with a zinc accumulation in the two bushes that pass through it. I'll just run a drill through them afterwards. I'll make sure all the paint is off it. (To be honest, if the manufacturer had done anything better than a dose of cheap matt black out of an aerosol, I probably wouldn't be in the position I'm in now! Over the years, I've tried various paints and potions on it - none of which has worked terribly well, so the whole lot is going to come off.
 
If you imagine your piece suspended from one of those holes, in an orientation that gives maximum vertical orientation on as many faces as possible, that's the way to hang it. In that aspect it needs to self vent and drain. The reason for vertical is to get as much surplus zinc to drain off as possible, before it solidifies.
 
MM5AHO said:
If you imagine your piece suspended from one of those holes, in an orientation that gives maximum vertical orientation on as many faces as possible, that's the way to hang it. In that aspect it needs to self vent and drain. The reason for vertical is to get as much surplus zinc to drain off as possible, before it solidifies.
Click to expand...

Yes, no problem. There are three bolt holes at each end where it mounts to the bodyshell.
 
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