[TheForge] OT -12v motors

[Grover.Richardson at gtri.gatech.edu]

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-----Original Message-----
From: theforge-bounces at mailman.qth.net [mailto:theforge-bounces at mailman.qth.net] On Behalf Of Jerry Frost
Sent: Tuesday, June 21, 2011 4:04 PM
To: Blacksmithing List Sponsored by ABANA
Subject: Re: [TheForge] OT -12v motors

Hmmm, your last post and this one raise a couple questions in my mind. #1 Are you really teaching your students to be slow learners?

One must crawl, then walk, then run.  Not teaching them to be slow learners (at least on purpose), just to be cautious until they have experience.  Experience I have heard is best seen by counting the scars on a body.  Too many and the person is impetuous.  Too few and they are not adventurous (tongue in cheek<G>).

#2. I agree, a butter fingered person carrying an anvil in the shop may well be a contender for most dangerous.

No food near the anvil, especially buttered toast<G>.

More seriousness now. Don't push into the wire wheel or buff unless you have to to get to the inside of a feature. Wire brushes and buffs work best at 
the ends of bristles, it's where the fibers carrying compound of wires don't slide across the project. If you push hard enough to bend the wires, they 
lay flat and don't cut, same for a buff. A heavy touch will also load the grit in a stone wheel reducing it's tooth while rolling the edges of the 
stock.

Agreed.  There is a touch that only experience provides, and with sagacious words from someone who knows, it is much easier to learn.  I like a stiff wire so that I may be aggressive in my push if necessary.

Guards on rotating machinery are good ideas but I've had things come through some guards and the ones nothing can get out of make it really hard to get 
things in through meaning you are working at BAD angles of attack. Learning to work out of the potential ballistic tragectory(sp?) is your best bet. As 
an added safety measure, especially when others are in the same area is to put something behind you like a locker to act as a scatter shield.

Yes.  Sometimes safety equipment actually makes things MORE DANGEROUS by limiting movement or access.  I consider most safety equipment to be vestigial in nature.  Reason is that if you have a real problem (like you indicate), the guard will be insufficient.  Wall breakers in your shop only protect the wiring from short circuits.  It is still possible to have an electrical fire or other problem, and the breaker won't even care.  Case in point.  I was running a piece of equipment.  There was an arc in the filament circuit across the little neon "POWER ON" indicator.  That arc didn't take out the 2 Amp fuse that was feeding the indicator and other stuff.  The arc didn't take out the 15 Amp breaker in the power strip (like on your computer).  The arc didn't take out the 25 Amp breaker in the wall box.  The arc DID TAKE OUT the 3 phase 200 Amp main input breaker to the wall box.  Well, at least the power went off, most of it.  We were also running power through another power distribution system to the same experiment (yes 2 feeds is inappropriate, but in this instance this was the only way we could run it).  The power from the second main was not removed.  It sounded like an indoor shooting range.

One of my side works is a plating shop where they do silver and gold.  Their buffing wheels are mounted 4' off the ground, on a 2' long shaft, and no guards or shields at all.  It is necessary in order to get to all sides of a pot, bowl, chandelier.  The same people have been working there for years.  Though I DO NOT RECOMMEND this for anyone, some are willing to take the chances and have the skill to minimize them.  Note that the whole back wall is an air filter that sucks air, grit, and everything away from them at high speed.


All the best.
I'll try to add some blacksmithing content next time.