large cooling coil.

[George Malcolm GriffettParticipant @georgemalcolmgriffett72482]

I have a very large vintage model into which I would like to install a large automotive quality electric motor  I have, which at  24volts quotes 5000 to 20000 RPM .

I would prefer to have a cooling coil around the motor ( the scoops and outlets are already fitted to the model) but the diameter of the motor is 74mm, does anyone know where a coil could be found or the soft tubing to make one of this size?

Many Thanks Malcolm.

[George Malcolm GriffettParticipant @georgemalcolmgriffett72482]

[Paul TParticipant @pault84577]

Hello Malcolm

 

You could use silicone tube which is available at most model shops or you could use 8mm copper pipe, which is soft copper and easily bent using a bending spring.

 

Paul

[Bob Abell 2Participant @bobabell2]

Can I say something silly please?

 

I`ve noticed that electric motors still run as normal when totally submerged!!!!!

 

So why not mount them underwater???

 

Crackpot idea…………….but is it?

 

Bob unhinged today!

[Dave Jones 3Participant @davejones3]

I personally would not bother with silicone tubign as it will not do a thing.

Right then what you really need is quite simple go out and buy someCOPPER NOT Kunnifer brake pipe and simply wrap around the motor you DO NOT need any bending spring or even filling it with sand it will bend no probs at all

 

 

 

 

dave

[Paul TParticipant @pault84577]

Dave Jones 3

 

I find your comments regarding this particular topic a little incongruous as silicone tubing is an excellent medium for creating a quick and very efficient cooling coil.

 

You can not bend soft copper around a 75mm motor without a spring or packing with sand because even recently annealed copper will kink and crease at such a tight radius.

 

Paul

[Bob Abell 2Participant @bobabell2]

Hold on there…Fat Boy!

 

Being a clever sod, myself…………….I think soft copper will bend round a 3 inch diameter!

 

I`ll go and get some and try it right now!

 

 

Clever Trousers

[Bob Abell 2Participant @bobabell2]

10 Minutes later…………….

 

……………….Yep!…………….Sure will!……….5mm dia

 

 

Only winding you up, Paul…………………..Bob

 

 

[Paul TParticipant @pault84577]

Now Now Bob

 

You will only confuse the children…….you will have them all running down to B&Q to buy copper pipe and a copy of “plumbing for dummies”

 

Paul

[George Malcolm GriffettParticipant @georgemalcolmgriffett72482]

Hi there Paul & Dave,

 

Thank you both for your informative and very entertaining comments I shall endeavour to test both suggestions but possibly avoid the third of mounting the motor under water!

 

Malcolm.

 

[Dave Jones 3Participant @davejones3]

Posted by The Fat Controller on 02/07/2009 07:07:55:

Quote:

Dave Jones 3

 

 

I find your comments regarding this particular topic a little incongruous as silicone tubing is an excellent medium for creating a quick and very efficient cooling coil.

 

You can not bend soft copper around a 75mm motor without a spring or packing with sand because even recently annealed copper will kink and crease at such a tight radius.

 

Paul

 

so sorry to be incongruous so please EXPLAIN to me therefore how I make brake pipes for cars then have I been doiing this wrong for the last 25yrs boy oh boy so have all the other mechanics in the world.If you had read my post properly which I doubt you have, KUNNIFER brake pipe will NOT bend it is to hard and will collapse as you have so rightly said. Copper brake pipe by it’s nature will bend even to 90 degrees by hand and will not kink so wrapping ti around a 75mm Motor is simply NO problem at all.Copper brake pipe by it’s nature is soft as S*** and will work.

 

Now the reason I stated that silicone piping is no good is simple silicone is not a conductor of heat copper is.Now as the heat is drawn away from the motor with the copper piping wrapped around it the water will instantly cool the copper and the warm water is drawn away with silicone all that happens is that the piping gets warm and does not cool the motor sufficiently,.

I have used both methods and have found that copper is the best soloution but make your own minds up 

 Dave

Edited By Colin Bishop on 03/07/2009 18:39:16

[Dave Jones 3Participant @davejones3]

Posted by The Fat Controller on 02/07/2009 14:38:29:

Quote:

 

Now Now Bob

 

You will only confuse the children…….you will have them all running down to B&Q to buy copper pipe and a copy of “plumbing for dummies”

 

Paul

 

Now I said BRAKE pipe NOT copper tubing

 

 

Dave

 

Edited By Colin Bishop on 03/07/2009 18:40:21

[Paul TParticipant @pault84577]

Whilst copper is an excellent conductor of heat it is doubtful that the narrow bore of a brake pipe could carry a sufficient enough volume of water to adequately cool a 75mm dia motor without being pumped.

 

I did not know that such things as copper brake pipes still existed much less were still being fitted to cars, how is it possible in this health and safety conscious age.

Cars are factory fitted with steel brake pipes as steel has the necessary strength to contain the huge pressure created by the hydraulic system.

It frightens me to think that car brake systems are being “repaired” with thin walled copper tube which is expected to withstand pressures of up to 2000psi.

[Dave Jones 3Participant @davejones3]

Sorry to be a thorn in your side The Fat Controller but brake pipes are indeed made of copper and copper/nickel, see:

http://www.automec.co.uk/frame_set.html

 

 

Dave

 

Post amended to remove irrelevant and unnecessary content – Colin

 

Edited By Colin Bishop on 03/07/2009 18:37:03

[Barry FooteParticipant @barryfoote68385]

Dave,

Come on amigo, let it drop…..We should all be friends……..Friendly PM sent.

Barry 

[Colin BishopModerator @colinbishop34627]

Topic Cleaned up by removal of unnecessary content.

 

Disagreements should be expressed politely and considerately and not in emotive language.

 

Colin

Edited By Colin Bishop on 03/07/2009 18:57:19

[ashley needhamParticipant @ashleyneedham69188]

Oddly enough I am in a position to require some cooling for the motor in the Seahawk (850) and was considering copper brake pipe. I am not sure that anything between that and small-bore central heating size exists in the sorts of lengths that we need and at a reasonable price. I assume that one would have to coil  the (whatever) pipe around a slightly smaller former so as to get a nice grippy fit and thus max  heat transfer. On a couple of my models I have painted the motor casing matt black and glued some card blades on to the couplings to fan the motor a bit? Never sure if it ACTUALLY did much, but its easy to do. A good idea I thought  was the fixing of computer type alloy heat sinks on to the motor casings with conductive goo (as per that geezer who built the V large Type21 frigate in the mag ). Maplins do a good range of small computer fans for cooling purposes, but I think ultimately, letting the heat out of the hull is what needs to happen. A good flow of air thro` the body of the ship must be the way to go, and is not easy to arrange. I have numerous “hidden” holes in my ships for this purpose, but when you actually add up the hole are it usually doesnt amount to much, and unless you arrange a bit of suck or blow, all you get is just a bit of heat lost through convective currents and the “sea” breeze .  Ashley

[Paul TParticipant @pault84577]

 Sorry Paul,

 

Reproducing PMs on open Forum is not permitted without the consent of both parties and me as Moderator but I have copied the contents while I decide what action to take.

 

Colin

Edited By Colin Bishop on 03/07/2009 19:38:32

Edited By Colin Bishop on 03/07/2009 19:39:03

[Dave Jones 3Participant @davejones3]

Ashley brake pipe is really cheap to buy costing around £10 a roll to buy.What you need is the COPPER type as it bend easily and yes it needs to be wrapped around a slightly smaller former you are correct  in what you say

Available through ALL good Motor Factors

 

 

Dave

 

 

 

[ashley needhamParticipant @ashleyneedham69188]

Dave, I think I may go with this. Realistically there is nothing else, the boat I have is fairly large and can stand a few more coils to compensate against possibly a lack of water through-put, and i could easily have a washer pump to push water through if required, at the boat runs at 12V anyway. Ashley

[George Malcolm GriffettParticipant @georgemalcolmgriffett72482]

Hello Dave, about to try the copper brake pipe as you suggested on my 74mm dia motor and have noticed that they can supply it in 5/16″ which would give a better flow from the two inlet water scoops on the model. Do you think this possible with this larger and thicker walled pipe?

 

Thanks Malcolm

[shipmate60Participant @shipmate60]

I have to say I go with the copper cooling coils.

The silicone is an insulator so will only lower the temp of the surrounding air rather than the motor case.

Copper (or Alumunium) tubing will transfer the heat into the water faster and more efficiently.

Before plate coolers were made the coolers on Ships Main Engines had a copper alloy core for this reason.

Bob 

[ashley needhamParticipant @ashleyneedham69188]

I enquired at our local motor factors, and a coil of 3/16 pipe was 16 squids. There  was enough for at least two coils on an 850 motor if not more tho`. I didnt get it needless to say but am going to try some VENTILATION first.   Ashley

[Author]

Posts