blowdryer = spudgun chamber fan and ignition source?

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redchigh
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Sun Sep 09, 2007 2:18 pm

Alright. I'm making these topics because I have a couple extra hairdryers and I was gonna shred one if it would work.

I think converting it to DC would be easy, but would the fan work? (I have a 2-ft long 4'' diameter combustion chamber, so I think a fan would help.) I don't know if it's brushless- how would I know?

My other question is could I could use the heating wire as an ignition source? (I figure I could wrap it around a match-head, but I was wondering if it would work without a solid to combust)

Also, one of the hairdryers is an "ionizer" would that contribute any interesting parts?
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singularity
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Sun Sep 09, 2007 3:11 pm

well if it really is an ionizer it should be generating at least a few KV, it could be used for a spark gap if you know what your doing. i don't know why you would bother using a hair dyer fan when PC fans are like $2. its probably got a diode rectifier thing in the fan so it most likely would not work with DC without some from of modification. and i would bet the heating wire is designed to operate at 120v not the 9- 24v you would most likely would be using (9v batterys in series). from my experience it a lot harder to use heat to ignite a combustion than you would expect (i have done several failed experiments with iron wool) i say go with a conventional spark gap they are more reliable
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hi
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Sun Sep 09, 2007 3:18 pm

i garentee you that it is a brushed fan. brushless motors are a little more expenceive and there is no reason to have one in a hair dryer.

@ singularity- im sure it will work off dc, at least the fan will. the heating coil (as you said) is designed to run at a higher AC voltage.

if you want it to ignite the fuel then you need to use AC. i think its unpractical to use a blowdryer as a fan/ igniton. it would probably work, but to me there is no point. to me its just bulky and doesnt look good, but im not going to stop you. :wink:
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redchigh
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Sun Sep 09, 2007 3:28 pm

Well the blowdryers are gonna be sold in a yard sale for 2.00.... so I'm not losing anything :)

Would anyone know how to modify (or where to find information on modifying) the ionizer.... What would I need to do to make a spark gap out of an ionizer?
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Fnord
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Sun Sep 09, 2007 5:33 pm

I would toss the coil and just use the fan. The problem with a coil is if it gets hot enough you don't have much control over how fast it heats up and therefore when the gun goes off. There's just too much brownian motion involved in the mixing process to get it to ignite the same every time.

Removing the coil would also allow you to use power sources other than a wall outlet (I figure the fan can't be using much more than 50 watts at full speed).
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