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Heard on the Hotline by Ted Mooney, P.E.
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p eople who are not yet comfortable with computers and the lnternet may have seen the recent television ads for "Web TV and wondered whether that ap-
proach would really give them access to the Internet and allow them to interactively participate in things like "Heard On the Hotline." The answer is yes!
First, let's explain that technology very briefly. Basically, what you do is use your TV in place of a computer monitor, and use the access box, which looks and works a lot like a video game, in place of a computer. You connect the system to your telephone line; the box dials out and accesses the Intemet via a proprietary service; and you are on line, simple as that. Your bills will include the purchase price of the access box, a monthly service fee for Intemet access of something like $20 per month, and your phone bills (if any) when your system calls the closest access number for the Intemet access service.
For neophytes, the advantages of "Web TV" are that the purchase price for the system is substantially less than for a computer, and setup is quite a bit easier.
While "Web TV" may be a useful introduction to the Internet, it's not a long-term solution for most people be- cause it has a long list of serious disadvantages compared to accessing the Internet with a real computer. First, while you can wander around the World Wide Web with a simple point and click device, you're not going to be able to seriously communicate until you get a keyboard, which is an addi- tional cost, and not yet available for some of the access boxes as of this writing. Second, a TV is not a great substitute for a computer monitor because it has insufficient resolution (for a nontechnical explanation of this, simply try to read the credits at the end of a television movie). While a television picture looks okay as long as the images are moving and keeping your eyes and mind busy, when you try to see static detail you discover how poor a picture televi- sion really offers. So are computer buffs impressed by "Web TV?" No, not at all.
But suppose you are a neophyte who was framing the question in your mind this way: "Should I spend $2,500 or so, and quite a lot of time, to buy and set up a computer and see what the Internet is about, or should I just wait?" To you we would say, please frame the question this way: "Should I spend $300 or so for Web TV and a few minutes to see what the Internet is about?"
SPONTANEOUS PLATE-OUT ONTO PLATING BARRELS
Currently in my barrel plating line we are having some problems because the polypropylene cylinders themselves
are getting too much metal and the parts inside are coming out with low thickness (the metal that is supposed to be deposited on the parts is deposited on the cylinder). We are plating copper parts with a tin-lead layer using methyl sulfonic acid in the plating bath. Does anyone have any suggestion on how to eliminate this problem or reduce it?
Luis Moreno, [email protected]
I 've seen this problem before. I think an easily deposited metal like tin gets the whole thing started, then everything starts to plate out. Tin salts cling tenaciously to just about everything. We get it with barrels that go through multiple processes (cyanide copper, electroless nickel, gold, silver). The only thing to do is chemically strip the metal deposit off before it gets too thick and hope that it doesn't come back.
Bill Vins, [email protected]
Try stripping the metal out of your barrel and then look at the inside surface. You probably have millions of tiny scratches and nicks. These sites will start plating for a multitude of reasons. Contact your barrel manufacturer for his recommendation on how to smooth it out. Also check your hole size. Plastic will peen over the inside edge of the hole to reduce the effective hole size. You may have to drill or ream the holes out so you can get more solution turnover in the barrel.
James Watts, James Watts Inc., [email protected]
I would agree with all that has been said, except I don't know of any barrel manufacturers who are going to be able to tell you how to smooth out the scratched polypropylene. If these are small barrels (say 8 in. x 18 in. or under) and light parts, it may be possible to convert to a barrel that uses replaceable screening instead of drilled holes.
Ted Mooney, Finishing Technology, Kinnelon, N.J., [email protected]
NICKEL ACETATE FOR SEALING ANODIZED ALUMINUM
We currently warm seal anodized aluminum extrusions in water at approximately 100°C (212°F). I understand that appropriate quantities of nickel acetate will help the sealing process. Could someone explain how it works? How much nickel acetate should we add? How can we check the concentration of nickel acetate?
Sanjay A. Bulchandani, Ajit India, sanjayb@ giasbm0 l.vsnl.net.in
66 © Copyright Elsevier Science Inc. METAL FINISHING • March 1997
