Cooling pinball machine

[jrock2004]

I am looking to build my first pinball machine and wonder what others had done to cool the cabinet? With the 2-3 monitors and that PC, I am sure it gets pretty hot in there. Would love to hear what other builders have done for cooling. Thanks

[kahlid74]

Air flow and cooling is a fun topic.  I've not built a pinball machine yet but I plan to in the near future.  Theoretically all you should need is air flow if your house/space where the pinball machine is located will be in a 65-70 degree area.  The biggest thing with airflow is to make it consistent.  Front to back.  Fans to push air in and fans to pull air out.  I would use at least four fans 200mm in size to move the amount of air you're looking for.

[PL1]

Remember to include a forced-air cooling path that goes between the playfield and the glass since that is a major area for heat-buildup.


Scott

[BobA]

If you use a high performance PC to run your games you may have to provide additional cooling for the CPU if air cooling is not adequate.   Depends on your MB and CPU.

[kahlid74]

Remember to include a forced-air cooling path that goes between the playfield and the glass since that is a major area for heat-buildup.


Scott

Scott is right on the money too.  Make sure there is a little gap where you can move air.  You can use Wood or Plastic of even cardboard to direct the flow over the screen.

[jrock2004]

Remember to include a forced-air cooling path that goes between the playfield and the glass since that is a major area for heat-buildup.


Scott

How would you go about cooling that area? I have seen others who do not put a space between the glass and the TV. What problems could this cause?

[ark_ader]

http://www.eicsolutions.com/thermoelectric-cooling-whitepaper.php

[PL1]

Like Khalid74 suggested, making a duct like the heating/cooling ducts in your house can direct the air over the playfield.

The reason this cooling is important is that heat buildup can reduce the service life of electronics.

The playfield display was originally designed to be vertical with heat rising off the front and back. (Put your hand close to a big screen TV that's been on for a while, you'll see.)

Once the playfield is on it's back, the heat is trapped in the dead air space under the glass and underneath the playfield unless you provide cooling.

If you approach it like cooling a PC with fans added to allow air flow over hot surfaces, you should be able to keep the hot-spot microclimates from prematurely killing off your system components.


Scott

[dandro]

wonder if using pegboard, like an air hockey table effect, would evenly distribute the air flow better? Never built nor seen a VPIN up close, so just generally speaking out loud here.

[MTPPC]

Most pinball simulators overdo the cooling. What you need to keep in mind is that the path of airflow is more important than the actual volume. "Enough" air is all that is needed. For both of my full-size simulators, I put 1 120mm fan between the coinbox and the computer and blows up toward the back of the playfield. The fanspeed is controlled by the motherboard case fan controller. The top of the backbox vents the air. My machines run cool and have never had over-heating problems. I run it for 24 hours and check it with a non-contact thermometer and its less than 15-20 degrees warmer than ambient.

The real answer is that your fan should be sufficient to replace the cubic feet of air in the cabinet every couple of minutes. If you have at least this much airflow, it can't have a delta T (change in temperaturefrom outside to inside) of more than 10 or 20 degrees.

Most go overboard because they like the LED lights of the big fans blasting out behind and under their cabinets and just don't really understand thermodynamics of a closed system.

[jrock2004]

Most pinball simulators overdo the cooling. What you need to keep in mind is that the path of airflow is more important than the actual volume. "Enough" air is all that is needed. For both of my full-size simulators, I put 1 120mm fan between the coinbox and the computer and blows up toward the back of the playfield. The fanspeed is controlled by the motherboard case fan controller. The top of the backbox vents the air. My machines run cool and have never had over-heating problems. I run it for 24 hours and check it with a non-contact thermometer and its less than 15-20 degrees warmer than ambient.

The real answer is that your fan should be sufficient to replace the cubic feet of air in the cabinet every couple of minutes. If you have at least this much airflow, it can't have a delta T (change in temperaturefrom outside to inside) of more than 10 or 20 degrees.

Most go overboard because they like the LED lights of the big fans blasting out behind and under their cabinets and just don't really understand thermodynamics of a closed system.

I think your points of overdoing cooling is what made me really want to open this thread. I will admit that cooling/airflow is not my area of experise. Thanks for all the input. Keep it coming guys and gals.

[kahlid74]

wonder if using pegboard, like an air hockey table effect, would evenly distribute the air flow better? Never built nor seen a VPIN up close, so just generally speaking out loud here.

Most likely it would be worse.  Peg board has a lot of dead area where the air would get caught and cause a strangle on the air getting through.  Essentially you'd lose CFM because of how the air would be reflecting.

Most pinball simulators overdo the cooling. What you need to keep in mind is that the path of airflow is more important than the actual volume. "Enough" air is all that is needed. For both of my full-size simulators, I put 1 120mm fan between the coinbox and the computer and blows up toward the back of the playfield. The fanspeed is controlled by the motherboard case fan controller. The top of the backbox vents the air. My machines run cool and have never had over-heating problems. I run it for 24 hours and check it with a non-contact thermometer and its less than 15-20 degrees warmer than ambient.

The real answer is that your fan should be sufficient to replace the cubic feet of air in the cabinet every couple of minutes. If you have at least this much airflow, it can't have a delta T (change in temperaturefrom outside to inside) of more than 10 or 20 degrees.

Most go overboard because they like the LED lights of the big fans blasting out behind and under their cabinets and just don't really understand thermodynamics of a closed system.

MTPPC is right about CFM and replacing the air inside the cavity every couple of minutes but recycling the air inside the cabinet will not be enough to get the hot air away from the screen.

Attached is a sketchup drawing I made quickly in case anyone else wants to elaborate.  Basically air flow principles would dictate you keep the forward air as clean to 180 degrees as possible for maximum CFM.  So the fan in the back would pull air in and push it over the surface.  The fans in the bottom would pull air out.  As the air travels over the surface and got to the front the bottom fans would pull the air back down creating an air flow.  You don't want the fans in the bottom to push the air up because you would be essentially hitting a 70-90 degree turn which can cut CFM in half.

Here's the basic idea.  Cool outside air pushed in from the back over the screen and sucked out the bottom.  a 1/2" MDF sheet is used as a "duct" where the air can be specifically targeted:


Here's an arrow showing a small 1" gap between the top and the air duct.  The monitor/TV would end where the duct begins:


Here's two more angles:



I don't remember a lot of cabs doing this type of air flow for cocktail tables, so honestly do you need it/is it overkill, sure, but getting that warm air away from the screen surface will prolong the life of that main TV/Monitor quite a bit like PL1 said.

[Xiaou2]

I agree that air volume is important.  However... even then, if air isnt forced over certain components or areas... they can still
get very hot, and decrease their lifespan.

 The main issue is that air is very much like Fluid.  It doesnt travel in a perfect linear line.    If you fill a pc case with air from the bottom...
it does not guarantee that the hard drives for example, will get cool.  The airflow might skip and swirl right around that area... causing hot-spots.

 Look at Laptop designs.  They use special enclosed channels and hoods, to keep the airflow strong and perfectly directed.
Even many of the newer pre-packaged machines, such as dells, have this same style of hooded airflow pieces.

 Also, well channeled air flow will be more deficient.

 Areas that are non critical, can be simply vented via some air holes, or passive vent screen.  Just remember that hot air rises, so UP is the most direct root it will take.

 Cool Intake air from the bottom of the machine, both passive (mesh) and forced (pathway restricted) for critical areas.

 Make sure that hot-outs and cold air in's   are not too close together... as sometimes that creates a warm air flood.

 Air Filters can help dust trapping... but they can also reduce airflow too much.  Be careful in this respect.. as its far better to have
well cooled equipment, than dealing with a little dusting.

 For Pinball machines, Id also install a separate forced air system that uses small drilled holes near the buttons / hand rests. 
To direct a nice breeze directly to the players hands, keeping them and the buttons free of sweat.


 So again, the biggest issue here is to try to create sealed air chamber, directing the cooling effects effectively..  to
avoid hot-spots, and cooling failures, due to poor fluidic flow / poor pressure.

 Best of Luck

[PL1]

One reason that many people appear to go overboard on the cooling is that the Nanotech Mot-Ion board is rather sensitive to heat-related problems IIRC.

It is one of the popular encoder boards for VP builds.



Khalid74 - Great illustration in sketchup -- there are only two things I would change.

1. Reverse the airflow so that it goes up and back. Since heat rises, the fans will act with the natural flow instead of against it.

For builds that use one, this will also provide cool air for the Mot-Ion board -- which should be mounted front and center on the cab for the accelerometers to work properly.

2. Instead of using a 90 degree bend to turn the air flow and send it over the playfield, either use a curved air deflector or mount the fans close to the top so they blow straight over the playfield.

Curved -


Straight - Like this, but wider.  The number of square inches at the input should be close to the number of square inches at the output.



Scott

[kahlid74]

One reason that many people appear to go overboard on the cooling is that the Nanotech Mot-Ion board is rather sensitive to heat-related problems IIRC.

It is one of the popular encoder boards for VP builds.



Khalid74 - Great illustration in sketchup -- there are only two things I would change.

1. Reverse the airflow so that it goes up and back. Since heat rises, the fans will act with the natural flow instead of against it.

For builds that use one, this will also provide cool air for the Mot-Ion board -- which should be mounted front and center on the cab for the accelerometers to work properly.

2. Instead of using a 90 degree bend to turn the air flow and send it over the playfield, either use a curved air deflector or mount the fans close to the top so they blow straight over the playfield.

Curved -


Straight - Like this, but wider.  The number of square inches at the input should be close to the number of square inches at the output.



Scott

10-4 man.  That's what I figured originally but even curved its still a 90 degree transition which takes away CFM.  I'm doing a cyclone dust removal system for my shop and they recommend no greater than 45 degrees for transitions.  Mind you this scale it is probably fine but that's why I changed the airflow to be back to front.

[Xiaou2]

Reiterating:  Trying to make hot air go down, will not work well.   There will be vortexes of air, and the flow will be a
bit of a mess in certain areas.  You will get hot-spots.

 Allow hot air to rise, and assist it by adding air speed and pressure from the fans.  That will reduce chances for dead
air vortexes, hotspots, etc..  and greatly increase cooling efficiency.

 Any heat sensitive PCBS:   Put a separate cooling fan in front of them, that forces air over the top of them.  Passive
cooling often isnt enough, nor is general airflow cooling.   You really need a forced air solution for these situations.

 Components which I recommend forced air cooling:  Hard Drives, CPUs, critical PCBs, most anything that uses a heat sink.

 Even if the internal temp rises pretty high... a forced air system on critical areas, can prevent lock ups and damages,
due to the very act of the strong breeze effect.

 And again, to maximize this, effect, one can also build ducts which enclose and focus the airflow over these parts, so that theres no way the air can vortex away from the area.


 Its very difficult to get a Positive pressure cooling system... in which theres so much air, that its pushing out everywhere.
Even so, you still may have hot spots.  Also, it may be very loud too.   This is why its better to use an intelligent duct system.

 I wouldnt worry as much about the 90 deg. thing, unless your talking about something like a Dust collector.  Which is probably what you were reading about.  The cooling system is far different from a dust collection system.  Also, with this,
you can have forced intake and forced out-put air fans / blowers.   As such, the vacuum it creates should be far more than
enough to cool very well.

 What will be more important, will be sealing of air leaks, reduced areas for cooling (ducts rather than large open spaces),
and powerful enough blowers / fans.


 Remember, you dont have to cool the entire box.  Just need to cool the heat generators, electronics, and provide passive vent escape for any excess.

[Gray_Area]

The real answer is that your fan should be sufficient to replace the cubic feet of air in the cabinet every couple of minutes. If you have at least this much airflow, it can't have a delta T (change in temperaturefrom outside to inside) of more than 10 or 20 degrees.

This. It's what HVAC techs do in figuring your home needs.

So seems to me the best simple solution is two intakes underneath the foot of the coffin, and two outputs with fans at the top back or sides of the coffin. Full draw and discharge, espcially because the monitor/playfield is at an angle upward that way.

[Xiaou2]

This. It's what HVAC techs do in figuring your home needs.

So seems to me the best simple solution is two intakes underneath the foot of the coffin, and two outputs with fans at the top back or sides of the coffin. Full draw and discharge, espcially because the monitor/playfield is at an angle upward that way.

 Sorry, but this isnt quite HVAC.

 HVAC uses Ducting.  It has no concern of cooling specialty heat sensitive electronics.  It has no concern of noise.  HVAC is located offsite, in basement and or outside.  Because of Ducting, theres no air vortexing, and dead-air spots.

 Again, think PC case.  Most specifically, extreme overclocked hot-box gamer pcs.   Forced airflow areas, with individual fans.  Large
diameter intakes pull fans.  Hot rise vents with push fans.

 Your idea is similar to whats needed, but its still needs some ducting to direct airflow, keep pressure, and keep dead air hot-spots, & vortexting, from occurring.

 Id intake at the bottom front, go into a duct that directs the air over the top of the LCD, between the glass, and then pushed out via
fans, in the upper back of the unit.   Possibly even entering the backbox, then out the top back of the backbox.

 The backbox, if carrying hot lighting, and or pcbs, will need cooling too.

 The Computer will probably be mounted to the rear wall of the base cabinet on a swing door?   Make a custom duct, and place intake fans from the floor of the cab, in front of it.   The air should flow over the HDs and CPU heatsink.   Possibly any video card or motherboard heatsinks that get hot.   Duct the exhaust out the upper rear of the cab.