MadModder
The Shop => Metal Stuff => Topic started by: mfletch on February 15, 2015, 08:40:56 AM
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Hi all I've got a friend who is a plumber so gets plenty of old taps etc can anyone tel me if you can just melt these down or would the chome cause problems.
Also can you melt down and cast a mixture of brass and bronze
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Sure someone with more knowledge will come along but I'm sure chrome gives off nasty fumes when melted?
I could be wrong though.
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I'm sure chrome gives off nasty fumes when melted?
I could be wrong though.
You would be spot on , ist not advisable to be melting items that are chrome plated ,it can be removed chemically.
At the end of the day household plumbing/electrical fittings are made from junk , more Zinc than anything else.
Personal I would not bother with them , better to go to the scrap yard and buy and ONE large old Bronze casting and melt that .
Rob
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Thanks guys it would have been a good source of brass but if its junk I will leave well alone
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The underground fittings ie fire hydrants and some heating valves are gunmetal .
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I'm sure chrome gives off nasty fumes when melted?
I could be wrong though.
You would be spot on , ist not advisable to be melting items that are chrome plated ,it can be removed chemically.
At the end of the day household plumbing/electrical fittings are made from junk , more Zinc than anything else.
Personal I would not bother with them , better to go to the scrap yard and buy and ONE large old Bronze casting and melt that .
Rob
Not disagreeing with your comment about lots of plumbing fittings being junk brass,but I happen to have a collection of DZR fittings. What would they be like for melting/casting?.....OZ.
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Hi OZ , I have no idea , I just no most plumbing fittings are junk brass for low pressure .
Thats why I said Household , if there Naval, Mines ,Pyro , Steam , high pressure then there more that likely to be Bronze , altogether a much nice material to work with .
Here you go http://www.ebay.co.uk/itm/like/251790152378?limghlpsr=true&hlpv=2&ops=true&viphx=1&hlpht=true&lpid=108&chn=ps&device=c&adtype=pla&crdt=0&ff3=1&ff11=ICEP3.0.0-L&ff12=67&ff13=80&ff14=108&ff19=0 :)
Rob
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Chrome melts at 1900C. I have to admit, I've used chrome plated diecast parts (a car door handles) to recover small amounts of pot metal for a particular purpose I had -- melting point for zinc based alloys is low 400's C -- a long way from 1900. The chrome just separated from the melt as large flaky dross.
Stainless steel which some use for aluminum crucibles contains chromium, and that gets considerably hotter. Then there's welding stainless, (or even grinding it to sparks) which definitely melts the chromium does produce chromium vapor. But we should be venting welding fumes anyway. Chromium is defintely hazardous as a vapor.
Brass melts up around 1000C and that's still well below chrome's melting point. But personally, I'd be beyond my own comfort level melting chrome plated brass. It's still too close a temp for me. Anyway, I've only melted brass on a few occasions (other than brazing) and it's not a metal of choice for me. Zinc fumes at brass temps are the problem.
I only melt outdoors, and stay away from the exhaust for any kind of melt. Blower off for approaches, and I'm in the habit of holding my breath for a quick stir or small pour. Some use masks.
Ironman has a recent video of making bronze from copper and tin, I believe.
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The "chrome" skin will be very thin, the nickel undercoat will be very much thicker and both will have much higher melting points than the brass. What you'd wind up with is a mass of molten brass with nickel / chrome skins wafting around, not much use for obvious reasons.
In the days when many motor car trims were ZBD, rejects from the various process steps would be remelted, but not those with plating defects, they were just scrapped. It wasn't worth the cost stripping off the Ni / Cr deposit. Occasionally one would slip into the mix and the resulting castings were always duff, you could see what were called in those non PC times "nodders" in the surface layer.
You can remove a chrome layer very easily and quickly with hydrochloric acid based brick cleaner, but the nickel will remain and you need specialist chemistry to strip that. I guess old un-plated brass plumbing fittings would be OK for remelting. Maybe a contractor replacing old installations with the new plastic stuff might have a reasonable quantity.
Eug
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Thanks for the reply's guys there very interesting the plumber usually has long chrome plated shower mixer pipe? I was just thinking too turn it down on the lathe first to remove the chrome
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I can't see any reports from people who have ACTUALLY tried melting brass plumbing fittings - with or without chrome plating.... Almost all the advice in this thread is supposition... :doh:
Most plumbing fittings I've recycled into some other part using the lathe or mill or brazed were pretty good stuff.
I would not hesitate to melt a pile of free random BRASS plumbing fittings to make a brass ingot. Just scoop the dross off and discard, don't breathe in the fumes and you'll end up with a nice lump of brass for new purposes. Large sections of brass are very expensive to buy.
Bronze and brass are not to be confused. They are quite different alloys for quite different purposes.
Cheers,
Joe
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Thanks for posting your experience Joe. I was getting worried that the large bucket of taps and fittings I took out of my house when I remodelled, and saved for casting, would be rubbish.
It certainly doesn't look like rubbish. Chromed taps and mixers etx, are very nice castings and quite massive.
Mark
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I have melted a reasonable amount of chromed fittings in the past, and I never grew two heads :wave:
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I can't see any reports from people who have ACTUALLY tried melting brass plumbing fittings - with or without chrome plating.... Almost all the advice in this thread is supposition
Cheers,
Joe
Hi Joe , "supposition" don't no were you got that from , I actually did melt a pile of plumbing fittings in my younger days and was not to pleased with the resulting mystery alloy . Now a days I just stay clear of such rubbish , but at the end of the day if that's all you have to work with hey Ho .
So what did you cast from you plumbing fittings ? , care to post a few photos of your work . :poke:
Cheers for the tip about Bronze and Brass being different , me thinks the clue is in there names lol
Rob
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Well, Joe, whether or not whatever advice you're concerned about is opinion or experience, It was delivered with tact, and that's a more valuable commodity than gold.
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In the UK the way to judge the quality of the brass in taps is, the older, the better. We used to have an organisation called someting like the "national water council" who used to set the specifications for all metal compositions in contact with water. and all brass taps were the same composition. Problem is I don't knopw when this organisation ceased to be, and became the "water research council" and now seems to be called either the "consumer council for water, or "water UK" I agree the quality of modern plumbing brassware is a little suspect, but brass is recycled over and over again. I have a huge tub full of electrical brass, taps, and general plumbing fittings which are going in the foundry as soon as I build it! Should I live long enough I will let you know what happens.............
Phil
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Thank for the comments guys I've asked my mate to just save the old brass fittings and they're only one way to find out so will do a melt when feeling better
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During our recent house refurb we fitted new tap sets in all bathrooms and loo's. Without exception now two years later the chrome plating is flaking off in large chunks. No doubt Chinese made taps. Supplier has replaced them but I've not fitted them as I have no doubt they'll flake in exactly the same way after a few month use. Absolute rubbish compared to what one got years ago <old fart mode OFF>
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Been carful of chrome poisoning snap-on tools change there tools if the chrome is coming due to chrome poisoning
I had a new ratchet from them other month
But your right just look at old chrome plated bumpers they last a lot longer than new chrome
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Chrome poisoning from a snap-on ratchet with peeling chrome plating doesn't sound right to me.
Is there any further documented evidence of this being a serious concern for hand tool users?.....OZ.
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Flaking Chrome plating on tools may not poison you Manx but the stuff can give one a nasty cut much like a paper cut. How do I know?? :hammer: Guess. :lol:
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Manxmodder posted
Chrome poisoning from a snap-on ratchet with peeling chrome plating doesn't sound right to me.
Quite right. There are no known hazards associated with metallic chromium. Think of how many times a week you cook in stainless steel vessels and stick stainless forks and spoons into your mouth without ill effect. The commonest form of stainless used in food grade utensils contains 18% chromium. Millions of people handle millions of chrome plated objects every day without any toxic hazard.
Many salts of chromium are indeed toxic and known carcinogens, which is why the electro / chemical process used in chromium plating is surrounded by legislation. The machinery has to be ventilated and the atmosphere monitored and the water used in the rinsing process has to be rendered innocuous before discharge to the drains.
So in short, metallic chromium is to all intents and purposes harmless, but the processes used in obtaining it are not.
Andrew posted Absolute rubbish compared to what one got years ago
In the high and far off days when we had proper industry, I was involved in the technology of plating plumbers brassware. Manufacturers worked to British Standard and checked the adhesion of the plated layers but all those factories went bust because ... well you know the story. I doubt Lif Ting Ni Kel is as pernicketty.
The quality gear is now produced by Germany and Italy; you won't go wrong with stuff by Grohe ferinstance.
Eug
(removed double post -- vtsteam)