Cooling brain fart

[Jeff Wohlt]

Okay...could be stupid but was in my hobby shop the other day going over all this cooling crap. I then looked down and saw a little gas tank from an old plane 8 oz or something...very small.

So I thought...how about a small pump (internal in the tank and runs on 9 v or whatever. It flows water out and to the esc and then motor and dumps back in to the tank. We are only talking oz of weight here and could end up being anoth balance weight...you only need a little water....depending on speed of pump but what comes out goes back in.

Then, I went ot the freezer and dropped 3 ice cubes in it...holy crap...cold water all the time.

So that was my brain fart. Screw all the external rudder pickup and goofy looping brass around the prop.

Sure would be nice for summer running.

now to find a micro dc pump.

Just maybe it could also cool cells?

[BIGDG357]

This actually came up in conversation with a few boat buddies and we scratched the idea because without some sort of radiator you keep moving the same water that is picking up more and more heat..... but hey ICE that could possibly work. Not exactly sure how big these are but but this just might do. http://cgi.ebay.com/FUEL-PUMP-6v-12v-rc-model-boat-gas-nitro-fuelpump_W0QQitemZ120477708689QQcmdZViewItemQQptZU K_ToysGames_RadioControlled_JN?hash=item1c0d07f191

[tth]

Jeff that sounds like a winner! It should work well for sport running here in the deep south.

[Rex R]

I note that the 'swiffer wet jet' has a small pump that runs on 6v (a 360 size motor)

[Simon.O.]

Or we could run setups that do not need massive amounts of cooling.
I run a few cooled setups and a few uncooled.
For SAW it is uncooled and we take the chance.
For race, I have no idea as I do not race.
For sport, just set your gear so that you do not need a massive amount of cooling or pumps and ice etc.
OR just make it slightly above mild and cool the conventional way.

Don't get me wrong here. I am an engineer and like to study and follow new ideas. When it comes to cooling, I can tell you now that there is nothing better than water (boats here) to cool our bits. :tiphat:

[Jeff Wohlt]

Pretty simple idea but it also begins cooling when pumped turned on. So you can begin cooling prior to hitting it hard and also let it run after your runs.

The water would stay cold for plenty long. If you prime the system then top the small tank up it would consistantly have all the water you need.

We sometimes just let our boats sit in the water for several minutes and then take off again...all this time the motor and ESC are cooling.

Rex, excellent idea on the swiffer! I was thinking micro internal pump that can be submerged but don't really need it that way.

[FloatDaBoat]

Anyone ever consider using CO2? A small bottle (such as used in a CO2 pellet gun) might be fitted with some sort of slow release pressure valve to release cold gas into the cooling tube system. Might not be a feasible idea, though. Simon.O. (being an Engineer) could possibly shed some insight into this hair-brained scheme. Oh, well . . . .

[Ken Haines]

Hey Jeff,
I have dabbled with cooling ideas as well.
The small tank you are talking about is way too small a volume to
cool your systems for very long. Try running a small airplane fuel pump using glasses of water. They actually move a lot of water in a short period of time. The delta between ice cold and cold water really does not have much effect either unless you can sustain that low cooling temperature. Not sure what else we can due to sustain that effect, but at the Nat's in T-offshore for the last heat I placed Ice packs around the Batteries knowing that I would again fully exhaust the cells. They did not swell at all in the last heat even when I ran the boat to dead zero, and the ice packs were still solid and frozen. Maybe recircing water like you said, but surrounding the tank with a modern cold ice pack. Or maybe use of a thermo-pile, but that takes a voltage source.
Just some added ideas. :thumbup:
Ken

[Jeff Wohlt]

The water exiting the system goes back in the tank so it would never run out...same pressure out as in. The ice cubes will keep water cold for a pretty long time. Not sure I want real cold water but enough to last a run then pop a couple in before racing. As you said, it just circulates.

Great idea with ice packs for the cells....certainly do not want to cool them too much and lose volts but you do not want them too hot either.

I will get a pump and play with something soon. For sport running where we run long times it may be a good option.

It also minimizes the drag from rudder water inlets....some think it is signifcant and others don't.

I like water pick ups on the hull but drag is obvious on those unless it is very little in the water...almost flat with the hull

[sailr]

There are small radiators with fans in the computer field these days. Pretty interesting stuff.

[sailr]

There are some interesting cooling components for computers these days.

http://www.xoxide.com/thermaltake-aqua-tmg1-radiator.html

[6S HYDRO]

why not just an ice tank for your existing rudder or pickups to flow thru and supercool the components and then out he boat so the hot component water doesnt ever touch the ice and melt it.

[6S HYDRO]

and no need for extra weight and batteries of pumps

[Rumdog]

It would take too much pressure to get it to flow back out of the tank through a silicone tube.

[Rex R]

swiffer pump:
been playing w/ one with an eye toward using it for a 'water cannon' on a (currently dark grey) project...anywho the unit pulls 3.1 amps when pushing water and it has a presure valve (to keep it from draining out when not running) that makes priming the pump a problem. removing the valve is easy though...and it throws a pretty good stream of water through my 'fire moniter'. imo the unit would be hard to fit into an 'N'class boat...methinks it would fit a 'P' class vee or cat w/o a lot of trouble.

[G Doggett]

It's an interesting topic, but I can't help feeling you guys are attempting to solve a problem that doesn't exist. !:tape:
Graham.:rockon2:

[pescador]

There are also these thermoelectric Peltier coolers they use in aquariums and computers maybe somebody could figure out an application for them.
Keep your water tank cold electrically? :olleyes:
http://shop.ebay.com/i.html?_nkw=peltier+cooler&_armrs=1&_from=&_ipg=

[Simon.O.]

Another approach to cooling if you realy need a lot for overloaded setups is to pre cool. I do this with my 4S rigger. I have a window washer pump and bottle and hoses that circulates iced water to the motor prior to a run. I can also use it post run.
This is only for my big rigger.
All of my other setups get what water the need out on the water and as Jeff said a few moments on/in the water prior to pulling it out is all they need.

[sailr]

could one of those be used as an 'electronic heatsink' on an esc?


There are also these thermoelectric Peltier coolers they use in aquariums and computers maybe somebody could figure out an application for them.
Keep your water tank cold electrically? :olleyes:
http://shop.ebay.com/i.html?_nkw=peltier+cooler&_armrs=1&_from=&_ipg=

[Jeff Wohlt]

Yes they can. They begin cooling pretty fast. Just need a 12v source. Oh and when reversed they heat to 140 degrees...warming lipos? Heck yes!

[sailr]

Very interesting. I wonder if a small 3S pack would be enough amps to drive it. Hmmmm, might want to do some more detailed investigation. I have seen the little coolers that plug into your cigarette lighter at garage sales pretty cheap. Might be worth buying one and tearing it apart. :rockon2:


Yes they can. They begin cooling pretty fast. Just need a 12v source. Oh and when reversed they heat to 140 degrees...warming lipos? Heck yes!

[Jeff Wohlt]

Yep, but you can buy them for $6 on e-bay. They are a bit amp hungry.

[sailr]

Yeah, I saw where they say MAX 6A. I suppose the more 'exchange' of heat to cool, the higher the amp draw. I would think a 3S 2200 30C battery should drive it although it is below 12V which might drive the amps up even more....right? Interesting to think about anyway. May not be practical on anything smaller than a P mono though. If it works it sure would be an interesting concept.


Yep, but you can buy them for $6 on e-bay. They are a bit amp hungry.

[Jeff Wohlt]

I think it will work fine on the 3s. They have some volt spread and I think all the way up to 15v.

Sure would be an easy adaption. I was thinking 1 per layer...if they are ceramic coated then no worries about shorting if touching the stack above.

Can a person split a himodel ESC to slip them in the layers?

[Steven Vaccaro]

This is cool, but I have a another suggestion for sport running. Run a larger mass motor than needed. For example I fried the 380L motor in my delta 25 because of a simple leaf in the tubing. I switched to a 540L, same speed but dont even need cooling any longer.

[Ken Haines]

Hi Steve,
Certainly you are correct on using larger than required motors, ESC, Batteries etc. to lower all the temps, but I'm challenged by the LSO & LSH restrictions. Especially in LSO when a 4 minute run is required. Since we have a spec power system your current options all sacrifice speed. I'm not much for that so I blow up a lot of motors.
I do beleive that we are looking at a chemical coolant ie; freon or ice packs or an efficient electrical cooling system. Maybe someone will have an even better idea. I'm still concerned about the coolant loop volume. Even the water pickup sytems turn the water pretty hot, just feel thewater outlet water on most of your boats when you pull them out of the water. Sometimes than little trickle of water is even hot enogh to sting you. Cooling takes time and if the flow cycle duration is too short the heat transfer will not have time enough to occur. I do not think however that slower flow is the answer either, although some would challenge this physics would not agree with them.
Pardon me everyone I work at a nuclear plant, some of the same cooling theories apply, maybe thats why I'm so interested in this topic. Sorry to geek out !!!
This is good stuff from everyone lets keep this going.
Thanks, Ken :thumbup:

[paulwilliams]

Pardon me everyone I work at a nuclear plant

http://blogs.citypages.com/blotter/Homer.jpg

:bounce:

[Ken Haines]

Hey Paul,
How did you get my photo ? lol.

Good one you got me. :zip-up:

Ken

[paulwilliams]

Hey Paul,
How did you get my photo ? lol.

Good one you got me. :zip-up:

Ken

:biggrin:

Sorry Ken, couldn't resist that one! Many years ago, I worked on this:

http://www.nda.gov.uk/ukinventory/sites/Sizewell/images/sizewellB_1.jpg

UK's first (and maybe only/last??) PWR.

Paul

[pescador]

I think it will work fine on the 3s. They have some volt spread and I think all the way up to 15v.

Sure would be an easy adaption. I was thinking 1 per layer...if they are ceramic coated then no worries about shorting if touching the stack above.

Can a person split a himodel ESC to slip them in the layers?

One thing with these, they move heat, they don't dissipate it you still have to use some sort of heat sink.
Should be easy to salvage one from a pc or even teamed up with one of the little esc fans.

[Jeff Wohlt]

Yes, when I look at my coleman electric cooler I have... most of it is heatsink...but that is for long-term use. If I can get cooling for the first 6 minutes on a board then I would be happy but until I actually hook one up to 12v and feel it I will not know. The bottom side of the ESC board is fine if it warms up but my desire is to keep fets cool from the top.

It may not work and I may be back to my ice water idea. I do know what comes out pretty warm but I also agree that more flow is better and cooler, Ken.

[hyrulejedi86]

OK, I may be missing something but why not use conventional water cooling, it's constantly being refreshed and the heat won't build in the tank?

[bwells]

I would assume they are trying to get away from the drag the conventional cooling system causes. I'm seeing added weight so far but I will continue to monitor. Innovation is what founded America!

[Rumdog]

A pinhole in a rudder is hardly drag. A lot of these guys run in hot climates where the pond water is consistantly 80 degrees or more. That may make it a little harder to keep things cool for sure!

[hyrulejedi86]

makes sense

[Ken Haines]

hyrulejedi86,
I do not necessarily need to replace the conventional cooling system, but rather enhance it.
Certainly there are some huge advantages of using the lake as the coolant. My problem in some set-ups is that it is still not keeping things cool enough. Sort of like the combustion engine can operate wth air cooling, but is even better with a radiator typr water cooling system. As some of our hobby is a test bed for other uses of electric power, could we actually dream up something to enhance the cooling on extreme set-ups ? That why this thread to me is so unique. I'm sure we all realize there are a lot of bright minds in FE and on this forum, who knows what we may come up with.
Good question,
Ken

[hyrulejedi86]

That makes perfect, sense. I guess having kept my personal experiances thus far fairly small I didn't think about it from that point of view.

Well, I certainly wish you the best of luck with it! Ice sounds good though.

[domwilson]

There are also these thermoelectric Peltier coolers they use in aquariums and computers maybe somebody could figure out an application for them.
Keep your water tank cold electrically? :olleyes:
http://shop.ebay.com/i.html?_nkw=peltier+cooler&_armrs=1&_from=&_ipg=

The thing about the peltier coolers is that one side will always be hot and the other side will be cold. You reverse the polarity so that you physically don't have to flip the element. Also, how cold they get also depends on the temp of the heated side. Keep that cooler and the cool side will get colder. The way these work is by moving heat from one side of the element to the other. Because of this, my biggest concern would be how to waterproof these so that water would not enter in between the grids. Thought about silicon but not sure how well it would handle the temperature differential.

[Steven Vaccaro]

Hi Steve,
Certainly you are correct on using larger than required motors, ESC, Batteries etc. to lower all the temps, but I'm challenged by the LSO & LSH restrictions. Especially in LSO when a 4 minute run is required. Since we have a spec power system your current options all sacrifice speed. I'm not much for that so I blow up a lot of motors.
I do beleive that we are looking at a chemical coolant ie; freon or ice packs or an efficient electrical cooling system. Maybe someone will have an even better idea. I'm still concerned about the coolant loop volume. Even the water pickup sytems turn the water pretty hot, just feel thewater outlet water on most of your boats when you pull them out of the water. Sometimes than little trickle of water is even hot enogh to sting you. Cooling takes time and if the flow cycle duration is too short the heat transfer will not have time enough to occur. I do not think however that slower flow is the answer either, although some would challenge this physics would not agree with them.
Pardon me everyone I work at a nuclear plant, some of the same cooling theories apply, maybe thats why I'm so interested in this topic. Sorry to geek out !!!
This is good stuff from everyone lets keep this going.
Thanks, Ken :thumbup:

Ken thats the problem with spec classes. Some people have deep enough pockets to continually abuse their equipment. I witnessed a person in n1 mono kill a motor in each heat. if you are going to spec a motor, the prop should also be spec'd. Its the restrictor plate of rc fe boating.

[crabstick]

Yesterday at racing, one of the guys picked up his whiplash and in the side of the boat where the esc was, there was some heat, which you could feel through the hull I suggested ( as a joke at first ) cutting a hole in the bottom of the boat and putting a piece of alloy plate in the bottom of the hull to act as a closed loop heatsink, It actually doesn't sound like that bad of an idea now.

I have a petrol offshore cat that I run in the sea and I really don't like running salt through the motor that said, I live 300m from the beach and wash the boat down with the hose including flushing the water jackets after each run.After reading Jeffs post about a small tank and pump, if you combine that with a heat exchanger (such as an alloy plate in a ride pad) you have closed loop cooling! and you can even add corrosion inhibitor to the cooling system.

Some SeaDoo 4 stroke jetski's run this system and use the ride plate as the heat exchanger.

I think it would be worthwhile in a boat you run in the sea. Only issue I can see is if the pump fails, you have no tell tale letting you know your cooling is working

[questtek]

I owned a 50 foot twin Diesel motor yacht years ago that used this technology.....it was called "Keel Cooling". On the bottom of the hull was a finned radiator fabricated from Naval brass, (for lack of a better description) The fresh water and coolant from the engine was a closed loop cycle but was routed through this "Keel Cooler" This way the boat diesel engines, which were GM 671's, never saw salt water. It worked great and I never had a temp or corrosion problem. The Naval brass had a high copper content thus minimized marine fouling. However, the max speed of this boat was about 12 knots or about 14 mph.......a far cry from the current FE speeds!

If you do this as an experiment I would consider using copper plate since the thermal coef. is much higher than aluminum. Drag may be a problem however unless it is faired into the bottom of the hull correctly.

As an alternate, I am currently using a cooling system for my "modestly" fast electrics that involves a "Chill" unit. I took a 35 mm film cnaster and wound inside lots of copper pipe with the inlet and outlet coming thru the top via sealed gromets. I fill the film canaster with water and put it in the freezer. The lake in front of my home is 76 degree sF freh water. I run the water inlet through the pre-frozen copper tubing in the canister and the outlet temp is 20 degrees cooler than the inlet temp. from the lake water.

To verify this, use an Eagle Tree Data logger that has 3 temp thermisters. I have one in the intake line, one in the exhaust line and one after canister cooling. This indeed does verify the temp drop from the "Film Can cooling" Naturally this is only good for several minutes...........but this is the duration of my rund anyway. Consider....there are MUCH better fluids to add to the film canister than water!

Hopefully this will stir some brain cells and the FE wizzards will improve on this concept much more!

[Ken Haines]

Questtek & Crabstick,
Both of you have great workable ideas these could be used in conjunction with open or closed loop systems. I'm starting work on a new LSO boat. This would be the perfect opportunity to incorporate both ideas. The Heat exchanger and the ice canisters. I will install velcro pads to mount an airplane fuel pump. I'm also going to use a motor mount with the cooling housing and a good cooling motor jacket.
This project could be a month away, but I will give it a try and post my results.
Maybe with all this cooling I can get the extra performance I'm hoping for out of these spec. motors even for a 4 minute offshore race.
I knew we have some brilliant minds here. :thumbup:
Thanks, Ken

[questtek]

You can count on me for help.....I have all the Eagle Tree monitoring equipment needed. I am working on an option that will solve the heating problems of ESC's that does not involve a pump, fan, Peltier cooler, keel cooler, dry ice or ice canister. I purchased 4 large 200 amp Mystery controllers to test the concept. Will keep the forum posted.......when the ESC's arrive.

[Jeff Wohlt]

Running cold water thru a coil with fluid around it is a good idea.

If only one layer of fets then the other side of the peltier is warm but water iff we water cooled that side of the unit? :) They do get cold pretty fast but only 40 degrees below ambient temps. Fine with me..plenty cold.

The pump and water may be a much less amp draw though and keep water flowing. I do not worry about water flow stopping with a pump.

How about a small tupperware box sealed and then cooling coils inside. You freeze the tupperware full of water and then just hook up the silicone tubes to it. You can take almost 3 feet and make a cooling coil and then flattend it out. I do think the cold water would be cooler running thru the line and faster. Easy to add a few cubes of ice...I have ice in the cooler when running all the time.

[Rex R]

if you need more cooling (colder fluid) consider dry ice and alcohol

[domwilson]

Another alternative... http://en.wikipedia.org/wiki/Heat_pipe

[Ken Haines]

Any type of tank container with the pre-installed cooling coils surrounded by water.
Keep this cooler velcro mounted so that you can take it right from the freezer to the boat, install it before each run. Have several all made up and frozen and just plug in the newly frozen cooler in for the next run. Even open loop would provide extra cooling.
Ken

[crabstick]

how about this,

The copper coils mounted to a copper plate that is through the hull

a. flush with a ride pad on a cat
b. flush with the surfaces on a vee.

I guess the main thing is getting the heat exchange plate in contact with water 80% of the time.

I have just sketched up a design of a through hull cooling plate, will transfer it to the pc and upload a bit later

[Jeff Wohlt]

Good idea, Ken. As long as enough pressure is coming from the rudder water it should work well. Simple and easy and use alum tubing KS. The more tubing the better and I know these are almost 3 feet of alum that I have made for motors.

Better than water>>>>>> break apart or cut the crap in the cooling things from what they sell for coolers (bags or the plastic hard kind and I have both in the freezer now) and put that in the box...it is slimey thick and stays frozen longer that ice.

Need to go to walmart anyway....I will buzz by the tupperware department and there are many other little boxes that can work. Sealing them up forever should be easy.

[sailr]

Wow! We must dub thee "Keeper of the Smoke" if you get that to work! Can't wait to see more!!


You can count on me for help.....I have all the Eagle Tree monitoring equipment needed. I am working on an option that will solve the heating problems of ESC's that does not involve a pump, fan, Peltier cooler, keel cooler, dry ice or ice canister. I purchased 4 large 200 amp Mystery controllers to test the concept. Will keep the forum posted.......when the ESC's arrive.

[questtek]

Good idea, Ken. As long as enough pressure is coming from the rudder water it should work well. Simple and easy and use alum tubing KS. The more tubing the better and I know these are almost 3 feet of alum that I have made for motors.

Better than water>>>>>> break apart or cut the crap in the cooling things from what they sell for coolers (bags or the plastic hard kind and I have both in the freezer now) and put that in the box...it is slimey thick and stays frozen longer that ice.

Need to go to walmart anyway....I will buzz by the tupperware department and there are many other little boxes that can work. Sealing them up forever should be easy.

I am just posting a new thread on ESC cooling...the moderator is reviewing it now. It should help answer all your questions and possibly even provide some helpful suggestions. It is only a start........there lots of improvements that can be made. Proper ESC cooling is a project worth a bit of thought time!

[Jeff Wohlt]

Well, her eis what I did.

Mini Cooler pack 4 x 2x 1" .97 at walmart

5/32 brass pipe. left over stuff

Silcone tubing...left over stuff

Drilled a bit smaller hole for the pipes and they seem to be sealed without glue at this point...remember, this stuff is thick and not water.

3 pieces of 6" brass.

Will it work....hell if I know but it looks cool! :banana:After frozen I will run it thru the pipes at a maintained water temp and see what it comes out at. Also, we are not looking for fast flow...just a small trickle coming from the exit.

[NorthernBoater]

I was thinking maybe we could use pass the water tube through a heat sink that has a peltier cooler attached to it. Cool the water before it hits the motor or ESC. An some either put a big heat sink inside the boat or mount the heat sink on the deck of the boat so air can cool it.

[domwilson]

When funds become available, I plan on purchasing another Himodel 200a ESC. I plan on running a peltier on top of the OSE cooling plate and on that the stock heat sink from a Himodel 200A ESC. I bet that will be cool running ESC.

[Steven Vaccaro]

Well, her eis what I did.

Mini Cooler pack 4 x 2x 1" .97 at walmart

5/32 brass pipe. left over stuff

Silcone tubing...left over stuff

Drilled a bit smaller hole for the pipes and they seem to be sealed without glue at this point...remember, this stuff is thick and not water.

3 pieces of 6" brass.

Will it work....hell if I know but it looks cool! :banana:After frozen I will run it thru the pipes at a maintained water temp and see what it comes out at. Also, we are not looking for fast flow...just a small trickle coming from the exit.

Jeff thats pretty large.

Did you ever see these?

http://ecx.images-amazon.com/images/I/41xgJiAhyBL._SS400_.jpg

[Jeff Wohlt]

This was my first attemp and a very easy one, I might add. Took all of 10 minutes to make. I was going to cut it open and slip the coil in and then seal it. It is less than palm size. I will also get a real size...I guessed at that when loooking at it.

It was a concept only but I might put it in my MM today and go run it. I may just take some readings from it as water passes thru and see if it even cools the water....if it can take 80 degree water to 60 I would be happy.

I still think the ice water with small pump is the key. You can turn it on prior to running and continue it even after the run. Ice water can stay cold for some time.

THe peltier is a great option. But you need 12v. The small fuel pump for rc runs on 6 or 12 volt.

Weight is not an issue at this point. It may weight 8 oz...or about the same as a gps I use. This is for bigger setups and boats.

[crabstick]

I would avoid the Peltier.

I will scan my sketch and upload soon, Ive redesigned my plate...

[norbique]

Finally, I read through this thread. I must say the first thing that came on my mine when I reached the part where some of you mention using small electric pump was the same what Crabstick advised later in the thread. A closed loop cooling system. My addition to Crabstick's idea is: what if you make the heat exchanger part so that it has small fins running lengthwise (not a flat piece of copper) on the bottom of the hull, so not adding too much drag, yet adding more water contact/heat transfer area?!

The peltier isn't good in my opinion for more reasons:
1. cost
2. it consumes a lot of electric energy from your batts.
3. since 99.9% of the fast electric boats have closed hulls, heat produced by the peltier will heat up the closed space of the hull. If you say this is good for the lipos, I can accept that, but you're still heating the air inside the boat = heating motors, ESC and everything inside.

[domwilson]

The cost is not that prohibitive.. http://cgi.ebay.com/1pc-12706-Thermoelectric-Cooler-Peltier-Plate-60W_W0QQitemZ250512603593QQcmdZViewItemQQptZLH_Def aultDomain_0?hash=item3a53b6f9c9

This is just one example. Current draw is around 6 amps. I don't think heat inside the hull would be a problem if you water-cool the "hot" side with a cooling plate. Thus making the "cold" side even cooler.

[6S HYDRO]

Are you sure you dont have to make the hot side hotter to make the cool side colder?

[domwilson]

Are you sure you dont have to make the hot side hotter to make the cool side colder?

Yep. That is why you normally put a heat sink on the hot side. Like in drink coolers, small refrigerators, CPU coolers, etc.

[norbique]

you're right mr. wilson i didn't think of that...

[Jeff Wohlt]

Well here is a cheap and easy pump.

58mm x 33 1.3 amp at 6v

http://www.cornwallmodelboats.co.uk/acatalog/graupner_1951.html

Might have to try one of these to see how well it does for flow.

[norbique]

that's a very nice gear pump.

[Jeepers]

wow this thread died!Did the ideas work?

[Jeff Wohlt]

Yes and very well, I might add. The cold water was the best. Questech did the hard work on this and shows many results in another thread you should e able to search. Cooling temps were way down.

When we need it the most is in the summer when it is 85-90 degreee water.

I think the biggest key is making sure all fets are in contact with the plate and the copper is much better than alum plate. But Alum is okay.

I have another cooler for the motor I am planning and will show it soon. Both of these can use the same pack to run the pump and the part I am trying to develop now.

[questtek]

Yes and very well, I might add. The cold water was the best. Questech did the hard work on this and shows many results in another thread you should e able to search. Cooling temps were way down.

When we need it the most is in the summer when it is 85-90 degreee water.

I think the biggest key is making sure all fets are in contact with the plate and the copper is much better than alum plate. But Alum is okay.

I have another cooler for the motor I am planning and will show it soon. Both of these can use the same pack to run the pump and the part I am trying to develop now.

Thnaks Jeff but you were a big contributor with lots of great suggestions. Here is the link:
http://forums.offshoreelectrics.com/showthread.php?t=10810

Here is a quick summary:
1. ESC's are an expensive but weak link in FE boats
2. The failure mode of the ESC is often due to overheating so more effective cooling techniques may greatly improve their performance and life.
3. The use of water cooling is one of the best and most pratical ways to achieve good ESC cooling. Although many other techniques have been carefully examined and experimented with, including thermo-electrics, fans, and even heat pipes, water cooling appears the clear choice.
4. Proper water cooling to an ESC is done to keep the FET temps in a reasonable range and to determine this thermistors were placed on the FETS as well as caps and cooling water system. Logging was done by an Eagle tree system both in the desk test set-up and actual lake testing
5. Origionally I was interested in passive cooling however through extensive testing it appears that a closed ice and water cooling system has the absolute best performance. The key is to keep cost, complexity and weight down.
6. There are two BIG advantages to the closed-loop ice/water cooling system:
a. It cools more than just the ESC but greatly assists in motor cooling.
b. Drops the temps down to an incredibly low value..from the 150's to the 80's-90's.

I have inlcuded a pic of the set up I am currently using in several FE's The tank is a light weight (0.9 oz) nitro fuel tank and note that I have a thermistor installed in it so I can keep track of the closed loop cooling temps, and the small 6 to 12 VDC pump (2.5) oz. To use this system, the nitro tank is half filled with water and frozen. Before putting in a FE the tank is tapped off with cold water. You can put the pump on a switch but for simplicity I just connect it to the same small LiPo pac I use in my BEC circuit. It runs all the time with minimal draw.

I continue to use the Eagle Tree system for logging and the 3 temps I measure are FET temp, coolling water temp and motor temp. I am very happy with the overall results!

[Jeff Wohlt]

Love it. Mine will be set up for this next year in most of my boats. Everything will run cooler. Tanks are cheap and you can take your cooler along with some ice and just make a ice water mix since the block will not stay solid for too long but in a cooler it should and with ice around it. It would be neat to have a nitro lid on it and extend it up thru the hull where you can just fill and drop some cubes in.

I also like pre-cooling and even letting her run after for a few minutes after a hard run.

The next is a motor cooler that should do very well.

[ozzie-crawl]

i think still having cold water running threw the system after a run is probably the biggest benefit that a closed system has, if you data log a run then watch the heat when you stop and every thing heat soaks
it jumps up a fair bit very fast, boat mite be running at a good temperature but by the time you get the lid of and temp the esc/motor it looks like its running a lot hotter than it really is
just my thought :rockon2:

[greeneyed684]

why not just use or make small pump to push water through existing cooling system . just an idea?

[Jeff Wohlt]

That is what this is. Closed loop so you maintain cold water.

[greeneyed684]

what i meant was instead of water being pushed into pick up [ open loop] why not circulate water through speed control, motor faster with small pump just thinkin ways to keep weights down but still be more eficiant in cooling just an idea

[questtek]

what i meant was instead of water being pushed into pick up [ open loop] why not circulate water through speed control, motor faster with small pump just thinkin ways to keep weights down but still be more eficiant in cooling just an idea

If you read the threads in this forum you can see this is exactly what we are doing. Closed loop means you only circulate the onboard water (ice and water actualy) and do not discharge or intake any additional water. The pump is very lightweight and operates from 6 to 12 VDC.

[Xcesive8]

Hey Questtek,

Where did you find that pump?
Wouldnt mind buying and playing around with this idea.

Cheers

[questtek]

Hey Questtek,

Where did you find that pump?
Wouldnt mind buying and playing around with this idea.

Cheers

I bought several of these pumps on E-Bay from a HK company. I lost the link but just do an E-Bay search and you will find several different small 12 vdc pumps for sale. Hope this helps.

[dc588]

hello! im new to this forum and im interest in this . i founf this liquid cool system online heres the link http://www.gaz-on.net/TCS-Thermal-Cooling-System-for?artpage=2

[questtek]

I went thru the link you provided. I have several concerns:

1. Price, this was listed as a disadvantage but I saw no system price in the documentation
2. It is based on air passing over a radiator to remove heat from a recirculating, closed loop (no additional fluid in or out), coolant.
3. It appears to be designed for brushed motors primarily while a majority fo the FE's use brushless and also water cool the ESC.

I believe the solution is better fitted to vehicles that have a high air flow. In FE's, however, there is minimal air circulation in the hull so the radiator concept would only be margionally effective.

Also consider the removal of heat by the radiator is based on the difference in temperature between the air (say 75 degrees) and the coolant (say 100 degrees). This is not a big difference. However by using ice/water solution exchanger instead of an air driven radiator, the temperature difference is between the ice water (say 35 degrees) and the coolant. This higher delta Temperature is critical for high values of heat removal from the coolant.

Since I am not sure of the price of the referenced air radiator cooling system, I can not compare it to the price of the small electric pump (about $10) and small ice/water cooling tank (nitro fuel tank about $5). This dos assume the motor has a coolling jacket and the ESC has water cooling provisions.

[dc588]

as far for the price its cost 180 for brushless and 150 for brush heres the link http://www.tcscooling.com/priceandavailabi.html its include everything from liquid and stuff. just add a gas tank like u said so the liquid can be cool, so its doesnt getting pump back, sorry for my sucks english

[Jeff Wohlt]

I think you will find that spending extra money for something that is really not set up for our uses will be a waste.

This thread went through very detailed testing in many forms but it came down to cold water thru a pump and using a can cooler on the motor and a good copper plate on the FETS. The numbers can't be beat by any other means.

For the price, the weight and for the cooling action, this one is the one to use.

The other nice thing about this system is you can cool prior to a run and even after. My summers here get to 100 and water is always 90 surface temps.

[questtek]

I totally agree with Jeff.

[FighterCat57]

I don't agree with the closed loop. You are putting hot water into the source and when the source's heat increases, you're left with no cooling, like a battery. Drained is done.

What I suggest is a small setup atop the rudder, with a coil inside that is surrounded by a freezable gel, similar to an ice pack.

The coil pack could be kept in a cooler at freezing until time to use and quickly installed outside the hull on the rudder and plugged into the normal water pickup.

The water intake remains at constant temps and is cooled by the coil pack and then sent into the hull. This way there is no risk of over temping your cooling source.

Just my .02

I'll make one up sometime. Sounds neat.

Carry on.
________
LIST OF GM ENGINES HISTORY (http://www.chevy-wiki.com/wiki/List_of_GM_engines)

[Jeff Wohlt]

We did that...still have mine in the freezer. Should be a pic on one of these threads.

Search questtek's threads and oyu will see that is exacly what we made. I had 3 brass rubes thru mine...slowing the water flow reduced othe output temps but it is heavier.

Give it shot and give us your feeback on this thread.

[FighterCat57]

We did that...still have mine in the freezer. Should be a pic on one of these threads.

Search questtek's threads and oyu will see that is exacly what we made. I had 3 brass rubes thru mine...slowing the water flow reduced othe output temps but it is heavier.

Give it shot and give us your feeback on this thread.

Ha! I knew you'd have thought of this already!

Have you tried anything with dry ice?

[Jeff Wohlt]

No dry ice. Not sure what would happen.

Did you find the pic of that I made?

[FighterCat57]

No dry ice. Not sure what would happen.

Did you find the pic of that I made?

Dry ice is lighter and has a higher cooling capacity. Might solve the weight problem.
Drag racers do this sometimes to chill the fuel being delivered to the engine to produce more HP.

[Jeff Wohlt]

Yes but it is the gas that cools...how will you handle this chunk of Ice? Get it wet and it begins to create gas and bubble like crazy.

[FighterCat57]

Yes but it is the gas that cools...how will you handle this chunk of Ice? Get it wet and it begins to create gas and bubble like crazy.

Typically a "coil in cooler" setup, where tubing is coiled in a cooler like container and just pass the fluid through the coil. The caution would be freezing lines if too much dry ice. That would be catastrophic.

The wheels are spinning.

[Jeff Wohlt]

Look at post #52 It worked well and slower water flow makes it colder.

[FighterCat57]

Ideally, we should be using the outside airflow to cool the ESC's. Like a plumbed CPU cooler with the heat sink sitting atop the boat somewhere. It doesn't make sense to try to dissipate heat in a sealed hatch.

Something like this; where the ESC is inside and the heatsink is out in fresh air and is plumbed into the hull.

http://ecx.images-amazon.com/images/I/31K5zmw8uAL._SS400_.jpg

[BHChieftain]

Ideally, we should be using the outside airflow to cool the ESC's. Like a plumbed CPU cooler with the heat sink sitting atop the boat somewhere. It doesn't make sense to try to dissipate heat in a sealed hatch.

Something like this; where the ESC is inside and the heatsink is out in fresh air and is plumbed into the hull.

http://ecx.images-amazon.com/images/I/31K5zmw8uAL._SS400_.jpg


That is a great idea. Heat pipes!

Chief

[FighterCat57]

Here's another idea, run fresh water through the heat pipes! You could also put the heat exchanger portion in a sandwich Tupperware container and fill it with ice. That would certainly dissipate a large amount of heat!

I really think using heat pipes and heat sinks as well as running water through them could dissipate 1000watts of energy in 5 minutes. Containing the coils in ice water or iced gel would only improve on that.


The heat is dissipated through the cooling fins, the water helps cool the fins... like a radiator with a constant supply of ambient or cool water.

http://www.newegg.com/Product/Product.aspx?Item=N82E16835118037

http://images17.newegg.com/is/image/newegg/35-118-037-S04?$S640W$

[Jeff Wohlt]

You just won't find anything smaller and more effici than the ice water system. I will be trying one this summer. A small cooler with a few chunks you can throw in the water res would be easy....leave it run while changing packs or whatever...

If you are set on a fin system I would mount it in the hull bottom to get splashed but again....you are now coolign it with 90 degree water or in the air at almost 100 degrees. No point if you can't supply cold water.

Did you read the tests questek did on the other thread? It is well worth reading and noting the numbers.

[FighterCat57]

You just won't find anything smaller and more effici than the ice water system. I will be trying one this summer. A small cooler with a few chunks you can throw in the water res would be easy....leave it run while changing packs or whatever...

If you are set on a fin system I would mount it in the hull bottom to get splashed but again....you are now coolign it with 90 degree water or in the air at almost 100 degrees. No point if you can't supply cold water.

Did you read the tests questek did on the other thread? It is well worth reading and noting the numbers.

Combine the two, not a substitute, but a compliment. If you get ice water to the cooling fins and then through the heat sink the effective radiant cooling coefficient is increased. (utilizing the fins as the primary heat exchange) The key is to have the fins directly attached to the cooling plate.

The other thing I would really like to try is the heat pipe with remote heat sink mounted on the exterior of the hull. This way the outside moving air would help cool the unit.

All fascinating stuff. I wonder how many calories it takes to melt a handful of iced cubes and how many calories of heat are actually given off during a race?

Link to other thread please. =)

[FighterCat57]

On the other hand adding the fins might actually dissipate the cold water capacity quicker!

BTW- I'm really anxious to see what comes of the ice water cooling setup.

[questtek]

You just won't find anything smaller and more effici than the ice water system. I will be trying one this summer. A small cooler with a few chunks you can throw in the water res would be easy....leave it run while changing packs or whatever...

If you are set on a fin system I would mount it in the hull bottom to get splashed but again....you are now coolign it with 90 degree water or in the air at almost 100 degrees. No point if you can't supply cold water.

Did you read the tests questek did on the other thread? It is well worth reading and noting the numbers.



I certainly agree with Jeff. We both did a lot of design and testing on various cooling systems and the one he metioned with small chunks of ice and a water circulating pump worked just great. Again, you can follow the details of our experiments at:
http://forums.offshoreelectrics.com/showthread.php?t=10810&highlight=questtek

Good Luck!

[FighterCat57]

I certainly agree with Jeff. We both did a lot of design and testing on various cooling systems and the one he metioned with small chunks of ice and a water circulating pump worked just great. Again, you can follow the details of our experiments at:
http://forums.offshoreelectrics.com/showthread.php?t=10810&highlight=questtek

Good Luck!

Thanks for the link, that thread rocks! :rockon2:

Sorry for joining in so late and re-stating the already done. :o

[FighterCat57]

Hey Jeff, have you looked in to endothermic reactions? There's some combinations of ammonium chloride (similar to cold packs) that might last hours rather than minutes... Perhaps an ammonium chloride injection system into the water cooling system. Senses temp and injects more ammonium as needed.. That would be one hell of a closed loop setup!

[Jeff Wohlt]

I have not but bet it is cold!

[norbique]

adding some salt to the ice lowers the temp even more.

[ray schrauwen]

BUt, corrosive....

[madgadget]

dry ice, that's what I may try.

[DyrtyByrd]

why not just use the pump with no tank to continuously run fresh water through the system while running and while idle i would think with positive vaccum on the pick up you could also move it up some to lessen drag and still keep water flowing
also if you run in a hot climate like i do the ambient temps of your equipment could range from 70 to 100 degrees while the water we run in is quite cooler think of this example: if your hands are cold in the winter and you use cold water to wash them it feels warm because its not as cold as your hands, wouldnt it translate te same on the warm side, if your motor is hot lets say 105 if you use 70 degree water to cool it would eventually balance out to 70 plus or minus a few degrees witch is deff not a harmful temp for our equipment i think the real problem is volume of water not temp and i think the pump would work just fine with out alot of clutter in your hull, just my 2cents

[norbique]

i agree! Where can I find an acceptable priced 6V 12V dc pump?

[DyrtyByrd]

im not sure i have some at work but they seem too big maybe a small window washer pump?

[CornelP]

Robbe and Graupner have some pumps for scale models. Window washer has a very big flowrate, it will just generate more problems.

[DyrtyByrd]

problems? how so? i would think the higher flow rate would be better for cooling, i would not consider doing this in a smaller hull say under 30" but in your 30" and up hulls running hot set ups or multiple items that need cooling could possibly benefit from the increased flow the only problem i see is duty cycle for the pump im not sure if they are meant to be ran constantly for 10 min. or whatever your runtime would be i guess you could have it switched through your transmitter.....
deffinitly doable inmo

[slash24]

did anybody ever try out that swifer pump? if so how did it work out. i would like to give that a go and throw a radiator in to just make a continuous circuit.

[chopslap]

i agree! Where can I find an acceptable priced 6V 12V dc pump?

http://www.sdshobby.net/electric-plastic-gear-pump-for-smoke-system-p-2158.html

[norbique]

Welcome to OSE chopslap, and thanks for the link, this is worth a try!

[chopslap]

Welcome to OSE chopslap

Thanks

After reading this thread, this is what I have come up with for the mini rigger I have just started to build: Make the skid(?), that covers the stuffing shaft, out of aluminium and solder tubing to it. There we have the heat exchange.

I have some of those pumps, they use a 380 size motor, it would be easy to use a much smaller motor and chop up the pump, reducing its size. There we have a pump.

Off track somewhat;

My original intention for the mini rigger, was to use an outrunner and air cooled esc. Is it alright to waterproof the esc with laminating epoxy? The radio gear will go into a waterproof box. Then again, both the servo and receiver cost less than $10, maybe I will just dunk them into the epoxy and put some grease around the output shaft.

[ManuelW]

mhh followed this thread quite some time:
Why to invest so much time and effort into the cooling of the components? You discuss about cooling 1000W within a few minutes! I have a completely different view, because dissipated heat of the components is just wasted energy from the battery and absolutely decreasing efficiency. Thats why I do on myself and also recommend to chose/use setups which don't get that hot even at high currents! Sure I try to make the normal water cooling circuit as effective as possible and if engines are available with fan I'd also go this way. In the HPR 135 Lightweight I built I use 2x 8S 5000 mAh 45C Lipos and completely empty them in 3:00min resulting in an average power of ~3000W per engine with peaks of 11.000W per engine. But the ESC's and the motors are choosen that way, that they don't reach more than 55°C. That may be an extreme example but you can scale it down to any other boat. If you have to cool away 1000W and maybe even use additional power for a pump and additional weight for heat exhanger, 2nd cooling circuit and so in - imagine how much faster and more efficient your boat could be without the additional weight and if you use this power just for propulsion.

Just a few cents from my side to think or discuss about!

Best regards,
Manuel

[Jacked1]

I just saw this and didn't read the entire thing but one thing I always thought would be cool is to replace the heatsink on the esc with a small aluminum box filled with ice. No tubes or pumps or anything.

I never attepted it tho because of the condensation that would be on the box would likely drip down to the esc.

Another thing I thought of was having a CO2 BB gun cartridge that you could dump though the esc cooling block, but I shot this one down in my head too because the air pressure in the boat would increase and possibly blow off the hatch of the boat.

Another thing that I am acutally doing with my 55" build is use an esc box and fill it with chilled mineral oil and submerge the esc's. The mineral oil is less likely to arc than air as well and won't let O2 to the esc if something gets too hot. And it will also cool the caps.

[norbique]

Doesn't the mineral oil dissolve certain plastic parts of the ESC?!

[Jacked1]

Not that I know of, I have seen entire computers submerged in mineral/vegatable oil for cooling.
It is also used (reffered to as transformer oil) to submerge transformers and high voltage switches to keep them from arcing.

[norbique]

Good, I know tranformer oil. :) I just didn't know mineral/vegetable oil has similar characteristics.

[Jacked1]

Yupp I am going to look for actual transformer oil eventhough I have heard it was the same as mineral oil just to make sure. A few oz shouldn't be too expensive. :thumbup:

[properchopper]

mhh followed this thread quite some time:
Why to invest so much time and effort into the cooling of the components? You discuss about cooling 1000W within a few minutes! I have a completely different view, because dissipated heat of the components is just wasted energy from the battery and absolutely decreasing efficiency. Thats why I do on myself and also recommend to chose/use setups which don't get that hot even at high currents! Sure I try to make the normal water cooling circuit as effective as possible and if engines are available with fan I'd also go this way. In the HPR 135 Lightweight I built I use 2x 8S 5000 mAh 45C Lipos and completely empty them in 3:00min resulting in an average power of ~3000W per engine with peaks of 11.000W per engine. But the ESC's and the motors are choosen that way, that they don't reach more than 55°C. That may be an extreme example but you can scale it down to any other boat. If you have to cool away 1000W and maybe even use additional power for a pump and additional weight for heat exhanger, 2nd cooling circuit and so in - imagine how much faster and more efficient your boat could be without the additional weight and if you use this power just for propulsion.

Just a few cents from my side to think or discuss about!

Best regards,
Manuel

Thank you, Sir ! Configure one's setup to operate within acceptable operating temperatures and the need for all this extra plumbing becomes unnecessary. Just tune for maximum efficiency - cooling overstressed/overheated components just band-aids wasted power.

[Jacked1]

Thank you, Sir ! Configure one's setup to operate within acceptable operating temperatures and the need for all this extra plumbing becomes unnecessary. Just tune for maximum efficiency - cooling overstressed/overheated components just band-aids wasted power.

There is nothing wrong with thinking out of the box.

[Rumdog]

It's kind of useless though. Why run such an improper setup that you need to re think the entire process of simple water cooling?

[Jacked1]

I am thinking more of just different ways of cooling personally. Not really needing to cool more because of a crappy setup.
If I did the same thing on every one of my builds, I would no longer have any interest in building.

[properchopper]

It's kind of useless though. Why run such an improper setup that you need to re think the entire process of simple water cooling?

Couldn't be stated much better :tiphat:

Consider : Power source [battery] comes to a fork in the road. On the right are the components that create forward motion.
On the left is heat generated from the components. The more power going to the right, proportionately,the more forward motion.
If too much of the finite power (dictated by the battery) goes to the left, the SETUP needs to be thought out,the way I see it, not the extra-measure cooling . If thinking outside the box takes you down the road to the left, that's fine with me.

[Peregrine]

I am thinking more of just different ways of cooling personally. Not really needing to cool more because of a crappy setup.
If I did the same thing on every one of my builds, I would no longer have any interest in building.

Good Point! Not everything you do need be for maximum efficiency, sometimes it can just be for the fun of doing it!! :thumbup1:

[Jacked1]

Also the cooler a wire (and this goes for esc's) the lower the ESR is and greater the efficiency. Two identical setups with one running cooler from better cooling the more efficient it will be.

And back to the cooling ideas. One I have been kicking around for my next twin cat build is remove a small section of the center of the hull and replace it with an aluminum plate and use this to heatsink the esc's to. There would then be more waterflow over the esc and no tubing or water pickup.

[areseaer]

You could use thishttp://www.mgchemicals.com/products/403a.html just need a way to push the trigger when needed.