Calculator Question

Happy Halloween!

I just wanted to post a quick question I had from a user that used the Jacob's Online Calculator, found on the website. This is a copy/pasted message from the email I sent back. His questions are in blue, my responses in black.

Question

Please help me to understand your calculator.

Here is a link to the main help page, which may answer some of your questions. 

http://hotwirefoamcutterinfo.com/Hot_Wire_Foam_Cutter_Info/JacobsHelp.html

I need the tempereture to be 160 degree celsius.
The length should be around 60cm.
The gage should be 32 because i am using it as a heater.
The diameter is 0.203 mm the volts would be 12 volts .
if I punch this on your calculator 

the result show that I need a power that is =+/- 7 Watt with the current of +/- 0.5 amps . Is this correct ?

So if I go to a shop for my particular application I need to buy a power supply that has 7 watt ,12 volts,0.5 amp.
Is this correct?

You're pretty much correct, yes.

Check out the electrical theory page to reference what I am about to discuss. 

http://hotwirefoamcutterinfo.com/Hot_Wire_Foam_Cutter_Info/__ETheory.html

Just remember that the VOLTAGE needs to be similar between what you calculated and what is on the power supply. From the power supply, the output voltage is always constant. But the amperage or current flow is a function of the resistance of your circuit. (See Ohms law).  The listed amperage on the power supply is the maximum safe output amperage for that power supply. 

Think of it this way. You need to find a power supply that is 12 volts, but has an amperage rating HIGHER than 0.5 amps. A 12v 2a power supply would work great, because you're always putting out 12 volts, but your circuit will only draw 0.5 amps and it's rated for a maximum of 2 amps.

If you reduce the length of your wire, or increase the gauge, you will reduce the resistance of your circuit. Lower resistance, when you apply the 12v from your power supply, will draw a greater current from the power supply. 

But a long-story-short, find a 12v power supply, and an amperage rating of anything higher than 0.5 amps, id probably say 1 amp or more. 

As for wattage, it is similar. The listed wattage is the maximum safe wattage output from the power supply. 

Also,

Watts = Volts * Current

...

Current = Watts / Volts

If you find a power supply that has just voltage and wattage, just divide the wattage by the voltage and you'll see the maximum safe output current. 


______




Okay everyone, as promised just a quick note. Take care and don't eat all your candy at once!


-carlo

New, new, and redone... Welcome YouTube!

Hello everyone! and happy fall!

For those of you who were directed here from my YouTube page, WELCOME!

I've found it much easier to compose messages within Blogger than I have the retched YouTube description window. Not to mention I absolutely despise the YouTube mail/message system, but hey... what do I know? CARRYING ON!

YouTube Video Description - Update 

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_ New Designs & Content _

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         - PDFs available on each design page for the cutter

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- New foam option?

- Use spray foam for foam cutting, cheap alternative?

- Maurizio from Ibiza, Spain suggested it's use.. maybe some testing in the near future

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_ Terrain Website _

I know I've been throwing out this teaser idea over the last year, but I am anticipating creating a hobby terrain website, much like I have for hotwirefoamcutterinfo.com. Just a main source of information, with informative links. The one difference is that this website would be founded upon user submitted content. 

I will have a website that contains the nuts'n'bolts to materials and categories (buildings, fences, rocks, trees, etc). But I will be inviting members of the community to submit videos through YouTube to be posted on the website.

Steve, the Kamloopian, attempted a website where a wikipedia of terrain making was going to be the cornerstone of the hobby community. But after being hacked, it broke him, and he's really left the community as a result. I intend on picking up where he left off...

I have started communications with the Kamloopian to acquire access to his site, GameTerrain.info and build the site from there. It will be a long process to see if we can work together towards a common goal, but he might give free range too. The big difference with the new style of site is while there is user submitted content, it will be managed and secure.

While the website will not have a STORE, per se, it will have links that may direct you to the submitting-user's own websites / online stores / ebay stores for you to purchase or contract their services. I have been trying to convince Etsy.com to create a new niche for this market, but I have not yet heard a reply, but that will come with time and persistence. 

Thank you everyone for bearing through with this published recap of my latest update video. Please feel free to comment and subscribe to my YouTube Channel and Blogger account. Stay tuned!

-carlo