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mm
07-25-2001, 10:39 PM
I'm new at this cyberworld stuff, but am deep into a 1920s wood power cruiser's restoration. Anyone have thoughts, knowledge, or opinions about what metal to use for a small galley counter-top? The old one was a mystery- maybe monel- but definitely had lead welding bits- not a good thing around food, etc. I'm leaning towards copper, but have heard that monel would be more historically correct. I'm looking for a balance between history and health.

Ed Harrow
07-25-2001, 10:47 PM
I can't help you from a historical perspective, but I suggest the amount of heavy metals one would accumulate from whatever held the copperwork (or other) together would not be an issue.

Solder today is available in lead-free formulations, and really the amount of food likely to be prepared on the surface is relatively small, and the amount eaten by those likely to be affected by it is probably even smaller. (Your results may differ.)

mm
07-25-2001, 10:55 PM
Thank you Ed Harrow for the reassurance. If copper is used, is it possible to "hammer" in the bends, i.e. no solder or welds? And, if the galley is used often for actual cooking and not just cocktails, is copper a reasonalbe metal? And, one last thought- does monel really look different than stainless? Or does it just age better?

dasboat
07-26-2001, 12:34 AM
Monel looks like stainless only duller than the stainless sheen.
Monel will not tarnish as does copper.Copper will look great at first,but will oxydize and be forever demanding your attn.
Re:solder,You would have to set food directly on the solder and leave it for an appreciable amount of time to start taking on lead or tin.

PugetSound
07-26-2001, 02:24 AM
Just a short note of clarification. "Monel" is actually a trademark name for Nickel/Copper (about 70%/30%). Heavier than your average stainless steel, it can be welded and formed and is very very resistant to corrosion (as any corrosion engineer will tell you, when it comes to seawater there is no such thing as 'corrosion proof'). There are a large number of NiCu or Cu/Ni alloys out there so don't limit yourself be asking only for 'monel'.

Also, while monel is corrosion resistant it will gall under certain circumstances which is why you never combine a monel nut with a monel bolt (always use a Kmonel -Al/Ni/Cu - bolt with a monel nut). K monel is much much stronger than monel (Monel has an allowable bending stress approximately that of mild steel) but Kmonel cannot be welded (at least not without losing it's properties).

Dale Harvey
07-26-2001, 09:00 AM
When you get around to priceing the Monel you will likely find it impractical. Stainless in the 316 grade can often be scrounged quite cheaply. School and governmental surplus auctions, scrap yards, commercial resturant supplies, ect. Unless you just must pass scruitineering by the concoures committee, it is probly the best way to go.

bainbridgeisland
07-27-2001, 12:14 AM
When I apprenticed in the early 70's, one of the master craftsman, Clarance Arnold (Clancy), specialized in renovating older boats. He did such a fantastic job that he had people waiting for years for his talents. He only accepted jobs where he had a free hand tied to a rudamentry budget. Applicable to your question, I watched him re-create about 6 new gallies.

He always used stainless steel for countertops and backsplashes. The boats were mostly built in the 20's and 30's. He usually matched the joinery and surfaces to the period of the original construction though the quality of hs work always surpassed the original.

It normally took him less than a day to make and install a countertop and backsplash the size of an office desk. He welded the corners, ground them smooth and polished them. I saw some 6 or 8 year old renovations he had done. The countertops always looked pristine.

I don't know what kind of stainless steel he used. My guess would be class 304. He initially installed wood countertops, sealed them and then covered them with stainless. I can't remember how he attached the metal to the wood countertops. Sometimes he installed insulation between them so they must have been attached around the edges somehow. They didn't warp with change of temperature so he must have had some free edges to accomodate the diferences in thermal expansion rates.

Clancy was in his early 60s back then so he is probably gone now. Customers were always blown away with his work. I loved being around when the Boss brought them by. He was largely responsible for the reputation of the yard.

Nicholas Carey
07-27-2001, 02:01 PM
Originally posted by Ironmule:
With respect to your cooking safety question, over on the Historical Trekking forum there've been several discussions of the safety of copper pots for cooking. It seems that when an acidic recipe is cooked and then left to sit in the pot for a while, enough copper can be etched from the pot to make for health problems. Recipes containing acids like vinegar and such seem to be OK if not left to sit around.

[puts on the tocque indicative of le chef de cuisine]

Traditionally, copper pots were always tinned. The only pots not tinned were specialized pots used for making caramel (melting sugar.) The reason that caramel pots are not tinned is that the process of caramel manufacture requires temperatures in the immediate vicinity of tin's melting point.

Pots are tinned by heating them to an appropriate temperature and then rubbing a block of tin on the hot copper -- it's basically a coat of pure tin solder. However, tinned copper is fragile and doesn't deal well with high temperatures. The tinning must also be renewed every few years (depending on use.)

In recent years, technology has advanced and a process of laminating a thin layer of stainless steel to a thick layer of copper has been developed. This has largely supplanted tinned copper in the restaurant trade as it is much more durable than tin.

Tinned copper pots are still available, though, as a cook, tinned copper pots are about the best pots available. The heat conductivity is absolutely amazing: no hot spots, almost not sticking. Builds strong arms, too: you want restaurant weight pots, which have 3mm copper walls (the lighter, 'household' pots have 1.5mm walls. A 25cm/10in saute' pan in restaurant weight runs in the vicinity of 4kg/8-9lbs.

Nicholas Carey
07-27-2001, 02:19 PM
Originally posted by mm:
I'm new at this cyberworld stuff, but am deep into a 1920s wood power cruiser's restoration. Anyone have thoughts, knowledge, or opinions about what metal to use for a small galley counter-top? The old one was a mystery- maybe monel- but definitely had lead welding bits- not a good thing around food, etc. I'm leaning towards copper, but have heard that monel would be more historically correct. I'm looking for a balance between history and health.

Well, pure zinc sheet is a very traditional material for bar tops. That's why the bar in a french cafe is referred to as 'le zinc.' Your counter may well be zinc -- it tends to turn into a shiny, deep grey surface. It has none of the 'snowflake' type of crystals typical of galvanized metal.

Pure tin makes a fine solder as well -- it used to be the only material toothpaste tubes could be made from.

Stainless has a certain utilitarian quality to it that's hard to beat. And either brass or nickel silver (german silver) would make a mighty fine looking counter top (if expensive.) Nickel silver actually has no silver in it: it's a alloy of 60% copper 20% nickel and 20% tin or so.

To do a good shop bending in sheet metal you'll need a sheet metal brake -- visit the metalheads over in rec.arts.metalwork for more information. But it may be more cost-effective to hire out the countertop to a sheet metal shop that specializes in food-grade work.

For copper/brass/nickel silver sheet, you don't want to lacquer it as the lacquer will get scratched. Just keep it polished and waxed -- the copper oxides are the easiest way it gets into food.