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Sparklers: Newsletter Challenge (11/01/05)

Posted November 01, 2005 6:00 AM

The question as it appears in the 11/01 edition of Specs & Techs from GlobalSpec:

You're visiting a friend who has a home machine shop. During a tour of the shop, you notice it's rather messy – buckets of iron chips and other machining filings that have never been emptied, as well as broken toys laying around like an old Etch-a-Sketch, remote control cars, etc. While chatting, he mentions his oxyacetylene welder is out of fuel and he needs to make a simple repair weld to a steel support in the back yard. You scan the shop again, spot some fine screen mesh, and ask if he has any Fourth of July sparklers. He smiles condescendingly and tells you that he does but "they'll hardly do the trick." You then say "Oh yeah?", and proceed to astonish him. What do you do?

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Member

Join Date: Oct 2005
Posts: 8
#1

Can you say Mcguiver

11/01/2005 8:31 AM

Grab some of those iron filings and mix them with the scraped off shavings of a few of the sparklers. Use the magnesium clay dust found in the toy etch-a-sketch to bind the two together. Be sure to pack the joint with the goop very well. Take one sparkler and lay it lengthwise along the joint to be welded. The fine mesh screen will help hold this goop and sparkler in place. Mount the business end of the remote control device adjacent to the area to be welded. Tape one of the sparklers to the arm of the actuator in such a manner that in the open position the sparkler is clear of the joint. in the closed (full swing) position the sparkler comes into contact with the joint to be welded. With the actuator in the open position light the sparkler and make haste to the controls. actuate the actuator to the closed position andwatch the sparks fly. The sparkler heat will light the magnesium in the clay dust which will melt the joint and the metal filings welding them into position.

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Power-User

Join Date: Jun 2005
Posts: 104
#2
In reply to #1

Re:Can you say Mcguiver

11/02/2005 9:54 AM

Sounds like a lot of work and the death of an etch-a-sketch to avoid a trip to the local welding depot. How clean of a weld does that leave? Sounds like there's a lot of foreign particles to contaminate the weld.

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Member

Join Date: Oct 2005
Posts: 8
#5
In reply to #2

Re:Can you say Mcguiver

11/02/2005 4:32 PM

I have to admit that it is partially a guess. The early etch-a-sketch had a couple different ingredients including some with magnesium. Later they seem to use a sort of aluminum powder and plastic as the meduim. So the scandal goes. Who knows what they are putting in our childrens toys now. I suppose there is some tycoon thinking that toys and tools are an excellent way to disperse radio active waste. If it will save a buck and make a buck i'm sure industry will fing a way.

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Participant

Join Date: Nov 2005
Posts: 1
#3

Sparklers: Newsletter Challenge (11/01/05)

11/02/2005 12:31 PM

I guess you're going to sieve the rusty iron bits to get some fine rust (iron oxide) powder, mix it with the aluminium powder from the old etchasketch, to make a thermite mixture - like the old fashioned method of welding broken railway lines. That's not a lot of aluminium to work with but you can probably use that mix on top to get the thermite mixture started, and layer mixed rust and fine filings of aluminium from the other scrap, underneath it. One quarter aluminium to three quarters iron oxide by weight would be about right. You might add some extra iron filings to bulk it out a bit. Pack it around the steel to be welded with some bricks and scrap to form a retaining wall around it, insert the sparkler, business end down, and light it from as far away as you can get with a blowtorch on a long pole. If you forgot to dry the ingredients you'll probably be incinerated in a firestorm of molten metal and slag, but otherwise a pool of melted iron will form, hopefully filling the join.

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Member

Join Date: Oct 2005
Posts: 8
#4
In reply to #3

Re:Sparklers: Newsletter Challenge (11/01/05)

11/02/2005 4:24 PM

were we going to weld this thing or blast it somewhere! Maybe the final answer is as long as its gone or pulverized who cares!

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