Hello, this time I decided to make a dedicated and improved bbq air blower. I have written about making a simple rotary tool here which I later used to blow air onto hot coal when they would loose too much heat and whatnot, I don’t like getting smoke into my face :P
But that one wasn’t very good, it used a cordless drill battery as a power supply and later the cordless drill died, a few weeks after that the charger fried because of a power surge, motor required 24v for optimal results.
So I just thought to make a better version, powered by a 9v battery with 3v motor and a basic speed control.
Whole thing is very simple and can be put together from junk that I am sure you have laying around somewhere.
To start it off, here is a list of things I used for this project:
- 9V battery – best to use a rechargeable one because you’ll save money replacing them and rechargeable batteries are cheap anyway. I didn’t actually have one laying around so I bought this one. Save nature you prick! :)
- 3V motor – guess it could be any kind of motor that work on 9V, but one I used was salvaged from broken chinese toys. This is the one I used:
- A Propeller – Had to buy this one as well. Took a set of 4 for 3$ from my dear friend dx.com. Those are for a quadcopter and when they arrived they were smaller than I have imagined, even with dimensions written there. So I think these would of been better.
- Flip switch – I find it more pleasant to use.
- Potentiometer with a handle for it – 100 ohms should be great and is enough to let through small amount of current where the motor spins slowly but doesn’t stop it completely (unless your battery is near death…), but all I got was a 470 ohm one, so the motor stops about half way. However those small blue adjustable resistors are not for such projects, because they take in like 0.1w or something, so they will just burn up.
- 9V battery connector – better to use a plastic one, I bought this one
- Some of PVC pipe – small enough diameter to house the battery, I used one that on one end I could put a plug. So I also bough a plug for it.
- Hot glue – Since I used a potentiometer with a screw, I didn’t have to use any glue for that, but had to glue the motor down :P
So that’s the list.
This is how I put it all together.
First I prepared the pipe by making holes for a flip switch and the potentiometer handle to stick out, connected those first, then connected the potentiometer and put it in place. Lastly I connected the motor and glued it to the pipe. When you are gluing it, be careful to press it firmly, or it won’t point forward.
And that’s basically it. Put a rubber plug on one end so that the battery doesn’t fall out and it’s ready to go. Even with these small propellers it still blows well, but we shall see for sure for the next BBQ :D
Whoah this thing proved to be more useful than I first thought, but using it I noticed a small problem – first the rechargeable 9v battery I described before wasn’t doing so well, actually it was so shitty that I threw it out just few weeks later, because it just didn’t hold a charge for no reason and would discharge rather quickly. Another problem was that somehow not all 9v batteries would be the same size, so not all would fit inside the pipe… and biggest problem of all is that I never had spare 9v battery laying around if I needed to replace one.
So I came up with a modification for this (an add-on if you will :P) – it’s just a 4xAA battery holder (AA batteries are easier to find around) coupled with a 9v connector… speed control still works ok, even though you get 6v instead of 9 now, but it’s still enough to keep the coal nice and hot.
I think the images will speak for themselves: