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Micro fan

Posted: Tue Feb 05, 2008 8:12 pm
by elitesniper
Hey guys would this fan fit 2'' sch 40 pvc,
[/url] http://www.radioshack.com/product/index ... =techSpecs
Product Length 1.57
Product Height 0.39
Product Width 1.57

and the pipe I.D for 2'' says 2
2.375

2.049

.154

.682

280

but i dont know if the fan will fit, I wana find this out before i buy it, help guys please :roll:

Posted: Tue Feb 05, 2008 8:27 pm
by potatoflinger
I think it should fit, but it's gonna be pretty close. I'm not sure if the math I used was the math I was supposed to use, but I found that the diagonal length of the fan is less than 2.3", so it will fit (if the diameter of 2" pipe really is 2.375)

I would get the fan, you could even grind down the edges a little bit if you had to.

Posted: Tue Feb 05, 2008 8:28 pm
by elitesniper
ah thanks i gotta search around more cause that fan is a bit pricey dont ya think?

Posted: Tue Feb 05, 2008 8:30 pm
by potatoflinger
Well isn't everything RadioShack sells overpriced?

Posted: Tue Feb 05, 2008 8:32 pm
by elitesniper
yea very true but i cant seem to find any other stores but your pretty sure the fan could fit 2'' sch 40 with a bit of grinding ? mabey frys electronics has one.

Posted: Wed Feb 06, 2008 5:56 am
by psycix
Yup think it would fit in.
Maybe check your local "computer store" they may have those for cheaper prices too.

Posted: Wed Feb 06, 2008 6:05 am
by jackssmirkingrevenge
You can very easily get a cheap electric motor from an old toy etc. and make your own fan out of soda can aluminium, secure it with a bit of epoxy and you're good. Remember, all you're trying to do is stir up the air, perfect fan blade dynamics aren't really an issue.

Indoor model aircraft makers fabricate their own propellers all the time, it's easy to use the same techniques.

Posted: Wed Feb 06, 2008 6:23 am
by Hotwired
Pretty much all motors in toys are brushed so maybe not such a good idea unless the motor is somehow outside the chamber.

Posted: Wed Feb 06, 2008 6:44 am
by jackssmirkingrevenge
Hotwired wrote:Pretty much all motors in toys are brushed so maybe not such a good idea unless the motor is somehow outside the chamber.
Or you could simply block off the cooling vents to isolate the brushes from the propellant, the motor is only going to run for a few seconds before firing anyway so it's not going to overheat.

Posted: Wed Feb 06, 2008 11:15 am
by psycix
Or make a handle outside the chamber so you can rotate it by hand! :P

Posted: Wed Feb 06, 2008 4:58 pm
by jimmy101
If it has square corners it won't fit.

The photo at radioshack shows rounded corners. It doesn't look to me like the corners are rounded enough to fit without modification. It should be pretty easy to grind the corners down enough to get it to fit.

It'll fit sideways easily. :D

Posted: Wed Feb 06, 2008 5:06 pm
by elitesniper
so your saying it will fit with some grinding right?

Posted: Wed Feb 06, 2008 6:36 pm
by jimmy101
elitesniper wrote:so your saying it will fit with some grinding right?
yes

Posted: Wed Feb 06, 2008 6:40 pm
by elitesniper
im getting my fan on the weekend, so when before i fire i turn on the fan so the air pushes > to the front of the chamber , then before i fire i turn the fan off? or leave it on while i fire? then when im done firing i open the back and turn the fan on again? but this time when i turn it on to vent does the fan have to reverse so the air gets sucked out of the chamber? or the fan is still running its regular position witch is > way to the front of the chamber.

Posted: Thu Feb 07, 2008 9:03 am
by psycix
A fan cant run in reverse.

But you should run it during mixing AND firing since having it on during fireing increases burn speed due turbulence.
For venting just keep it on, it doenst matter wich way.
Either if you blow the burnt air out of the barrel or suck it out of the back, its the same thing.