Cooling Fins .. Cheap or Repurposed a plus!

LI-ghtcycle

10 MW
Joined
Aug 29, 2009
Messages
3,818
Location
Oregon City Oregon
Heya all! I have done some digging through old posts and such on ES, but nothing I found mentioned a good used or cheap source of cooling fins for a 5in diameter motor casing.

With some googling, I was able to find this:

spd_2006052745653_b.jpg


But no idea on what size it is, or how easily I could find one.

I will need it to help cool one of these motors:

BLDC%20Motors%20for%20Light%20Weight%20Trikes.jpg


The outside diameter is 127mm or almost exactly 5in. by 108mm or 4 1/4 in. long.

I would love to find something at the local junk yard or craigslist that would be useable for this, I also wonder if some of the curry motors' casings might be the right size to use (I should be able to get some of these cases locally pretty cheap or even free).

I'd prefer something that is pretty easy to attach, but I'm not against just using a hose clamp to hold them on if that works. :wink:
 
If you're just looking to add fins, there is an idea I have had but not tested:

I have seen some really thin (less than 1/32") sheet aluminum that comes folded sine-wave accordian-style, with about 1cm "width" ("peak-to-trough", as it were). I can't remember what it was part of, but I *think* it was a filtration system in rackmount fan-cooling units. It was about two inches "tall", and not quite two feet long when taken out of the system (since it expanded a bit). There was something akin to very coarse steel wool in the troughs on each side, trapped in a framework that would guide air thru it; this was quite dirty at one end and very clean at the other--fairly obviously meant to be washed or blown out periodically. I am not sure if I still have the stuff anymore, after the cleanup. :(

Imagine the corrugated core section of cardboard boxes, without the outer and inner walls. It's like that, only larger and metal.

It could easily be epoxied to a motor case using thermally-conductive epoxy, or simply banded around it, with a little bit of heatsink compound on each inward-facing peak where it touches the motor casing. It's so thin and flexible even rubber bands would probably hold it pretty evenly tensioned and fairly secure.
 
Oooh, i've got an idea,

how about if you got the nasty aluminium wires out of a GE motor or similar, and wrapped it round the can.

To ensure good transfer of heat from can to wire, you could bed them down in a layer of that heat sink goo compound. You'd cut shorter lengths of the animalium wire, and leave the ends sticking out so it looked like a toilet brush.

No one would steal it!
 
Both very interesting Ideas!

Any ideas where I would look for something like the material you're describing AW?

Erogo said:
Oooh, i've got an idea,

how about if you got the nasty aluminium wires out of a GE motor or similar, and wrapped it round the can.

To ensure good transfer of heat from can to wire, you could bed them down in a layer of that heat sink goo compound. You'd cut shorter lengths of the animalium wire, and leave the ends sticking out so it looked like a toilet brush.

No one would steal it!

I really like the sound of this, but I have no idea what you mean by the "nasty aluminium wires" exactly?
 
They make oil filter coolers like this. I've seen some cheap ones. I think they are thin and bendy enough to conform to the curvature of a motor even if they are off a little. For 5" diameter they might have something for you. Universal type design, so should be affordable.

I've not tried these ones, just a random link a search comes up with: http://www.nfauto.co.uk/oil_filter_cooler.htm
 
LI-ghtcycle said:
I have no idea what you mean by the "nasty aluminium wires" exactly?


Mm, some of those motors are wound with aluminium wires (I'm sure it wasn't the non-US spelling throwing you off :D ). I call them nasty because I prefer copper.

this one

http://www.google.co.nz/imgres?q=gentle+annie+motor&um=1&hl=en&safe=vss&client=firefox-a&sa=N&rls=org.mozilla:en-US:eek:fficial&tbm=isch&tbnid=RNIfy-0GEjylIM:&imgrefurl=http://www.trademe.co.nz/Home-living/Laundry/Washing-machines/Top-loader-6kg-under/auction-402534746.htm&docid=P6Eaexyx75_X9M&itg=1&w=352&h=264&ei=gERoTtjOH9CciAehm4ntCw&zoom=1&biw=1024&bih=1149

is alanimium, because it's yellow (painted or whatever), and this one:

http://www.google.co.nz/imgres?q=gentle+annie+motor&um=1&hl=en&safe=vss&client=firefox-a&sa=N&rls=org.mozilla:en-US:eek:fficial&tbm=isch&tbnid=u1LDBxL-J8dMbM:&imgrefurl=http://www.thebackshed.com/forum/forum_posts.asp%3FTID%3D3113%26PN%3D4&docid=J9sw2yKznpuqKM&w=250&h=250&ei=gERoTtjOH9CciAehm4ntCw&zoom=1&biw=1024&bih=1149

is copper because it's ... copper-coloured (but probably also coated eh).

If you can do without some copper wire, that would work just as well obviously, copper being pretty handy at conducting heat. It's just that if you've got aluminium wire around you've probably got fewer other uses for it.
 
vanilla ice said:
They make oil filter coolers like this. I've seen some cheap ones. I think they are thin and bendy enough to conform to the curvature of a motor even if they are off a little. For 5" diameter they might have something for you. Universal type design, so should be affordable.

I've not tried these ones, just a random link a search comes up with: http://www.nfauto.co.uk/oil_filter_cooler.htm

Oh that is perfect! :D

Now I just need to find a local hot-rod shop or something cheap on ebay!

Thanks! That is just the kind of thing I was imagining. 8)
 
Hmmm they aren't cheap! Looks like the cheapest ones being sold for a oil filter cooler start at about $30 ... asking on Alibaba, might have a lead there.

I can't believe something like that costs more than about $5 + shipping!

I don't have to have one that fits 5in exactly, I can always take a smaller one and fit it to the outside, only going to be able to cover 75% of the casing anyway as the bottom will be attached to the frame.
 
LI-ghtcycle said:
Hmmm they aren't cheap! Looks like the cheapest ones being sold for a oil filter cooler start at about $30 ... asking on Alibaba, might have a lead there.

I can't believe something like that costs more than about $5 + shipping!

I don't have to have one that fits 5in exactly, I can always take a smaller one and fit it to the outside, only going to be able to cover 75% of the casing anyway as the bottom will be attached to the frame.

here is one that I got on ebay in the UK last year. the cyclone motor is 80mm diameter and had to open it out and put a bolt through it also cut the width down (they are ade for 72-75mm diameter I think and available in blue or red)...........and I paid £2.50 for this (under $5 including postage) nos from a car parts seller. they did not sell well in the UK :wink:

keep looking

Ian :D
 

Attachments

  • DSCF0007.JPG
    DSCF0007.JPG
    83.3 KB · Views: 2,323
Thanks Dingo!

That is exactly my hope! I might end up buying two and having to modify them to get the maximum coverage, but that is about what I am looking for.

I'm also wondering what might have a different design, I'll call it "radial" in that the fins are turned 90DEG from what most of what I have posted like this style:

e_eqt3r2238125_0.jpg


I might eventually build a "blower box" since this motor is going to be out of any normal stream of air that would be available for cooling where I will have it positioned behind the seat of my recumbent.

Not only will it be shielded from normal air flow being behind the seat, but it will also be surrounded on three sides (top and sides) by cargo pods.

I might devise a loose fitting "box" that would allow me to have a small PC style fan blowing air in from the bottom, and flow would go around then out the top of the box to give maximum air flow, the "radial" style fins would be ideal for this.

I'll put together a crude drawing of the box later today when I get a chance.

I'm finally able to visit the bathroom less often, and getting my strength back up (had a summer flu or more of the usual, hard to tell which :roll: ) so today I should be able to get some stuff done around the house, if not in the garage too! :D
 
Use a squirrel cage type of fan (radial flow), rather than the typical PC case fan (axial flow); it moves LOTS more air for the space/power. ;)
 
amberwolf said:
Use a squirrel cage type of fan (radial flow), rather than the typical PC case fan (axial flow); it moves LOTS more air for the space/power. ;)

Great idea!

Now I just need a squirrel and a case of red-bull (hey I could just use him to power the bike! :D )
 
would something like this work for your system? but instead of using the copper plate that mounts to the CPU, you could use a small copper tube that wraps around the motor.

http://www.ebay.com/itm/12-VDC-COMPUTER-CPU-LIQUID-COOLING-SYSTEM-16-1361-/380303532473?_trksid=p5197.m7&_trkparms=algo%3DLVI%26itu%3DUCI%26otn%3D4%26po%3DLVI%26ps%3D63%26clkid%3D2643427287372955749#ht_1435wt_963

Alex
 
honduran_kid said:
would something like this work for your system? but instead of using the copper plate that mounts to the CPU, you could use a small copper tube that wraps around the motor.

http://www.ebay.com/itm/12-VDC-COMPUTER-CPU-LIQUID-COOLING-SYSTEM-16-1361-/380303532473?_trksid=p5197.m7&_trkparms=algo%3DLVI%26itu%3DUCI%26otn%3D4%26po%3DLVI%26ps%3D63%26clkid%3D2643427287372955749#ht_1435wt_963

Alex

That is a very attractive option, but more cooling than I would need, and I'm really hoping to not even need a fan on it, just wanting to effectively cool the motor more than it does by design, not because I expect to burn it up, but because running cooler it will just perform better in general and last longer.

I've really heard good things about the "radial" style cooling fins, and I might use a combination cooling fin/mounting bracket since I will have to build something to attach to the bike frame anyway, I'll just build it into the mount so I kill two birds with one stone. :)
 
StudEbiker said:
The 300w & 600w BMC motors have cooling fins that slip on and off the motor. I have this one off of a motor I fracked up. If you think you can use it, let me know and I'll send it out to you.

Wow, what an awesome offer! :D

I really appreciate that man, but since I'm going with a different style of fins (it seems that in testing some have found the lateral or longitudinal fins that most motors have that run the length instead of the width of the motor are prone to uneven heating, so I am going to go with the "radial" style).

The "fins" I will be using will be 1/4in plate aluminum that go around the motor like this:

Cylinder-for-Air-Compressor.jpg


VS the typical electric motor cooling fins you see like this:

20112111277628.jpg
 
Back
Top