Shoebox cooling radiator continued from "Shoebox Compressor Parts" Thread ***(UPDATE 10/7/24)***

[Revoman]

****See last thread here for the latest information.****
I have experimented with the speeds and agree that it does remain cooler using slower speed. I have zero issues with the timing of my fills, the Box works great in doing so.
I recently (yesterday) have added a small radiator to the inflow side of the fan and am running ice water through the radiator to give it more cooling. I am in the very early stages of testing at this point and do not have an outcome or data yet but will post likely in a week or two with that information. The radiator was only about $25 by the way and looks very promising as it is putting out <50° air to the cylinders. The ambient temperature yesterday was around 76°. Since I live in a hot clime (most of the time), it's important to me that the air is as cool as possible to aid in mitigating the possible heat issues.
My humidity meter shows <30% normally (unless overcast) and I usually top-off my tanks between 15% and 25% humidity, even having a pre and post moisture filters, thus the normally hot temperatures.
Mike

 

[Revoman]

Tackleberry --=--
I bought the radiator through Walmart, took a couple of weeks to get. Not a deal breaker as I already had the Box fan, but this rediator comes with a fan, however the specs on the Walmart page neglects to state that it's 204-220v, not 120v as needed. I'm not certain that it wouldn't work as I didn't try though. I picked this one because it has copper coils instead of plastic, I think that copper would transfer temperature better. (Unfortunately, made in China....I hate that)
As stated, I'm in process of running it through testing, but looks very promising so far. I currently am using a small bucket for the aquarium water pump but need something larger for a better heat sink.
I initially planned to install the radiator along with the fan on the removable front panel, I drilled holes in the panel to allow the air flow. I ended up just using the stock Box fan, blowing through the holes instead. I also added a piano hinge to the right side of the front panel to allow lubrication of the pistons without removing the front panel.
Pictures to follow later today.
Here is the Walmart radiator....

Small shell condenser radiator refrigerator freezer air-cooled water-cooled aluminum fin and copper tube heat exchanger with fan - Walmart.com​

Arrives by Mon, Dec 4 Buy Small shell condenser radiator refrigerator freezer air-cooled water-cooled aluminum fin and copper tube heat exchanger with fan at Walmart.com
www.walmart.com

 

[Revoman]

Okay, attached are pics of the entire Box set up from low pressure Milton pre-filters, to the Box and water pump, radiator on back and close up of hinged front panel for lube access. Also included is the box that the small water pump came in for the part number information.
Any questions, just ask, not a problem. As stated however, it is very early in testing and I will provide more detailed information when it becomes available.
Mike

 

[Revoman]

jking --=--
I ran it with the cover off for a long time, also added an external fan (table model) off to the right side, blowing in line with the pistons to try and keep it cooler. Not sure that worked as it is in essence blowing hot ambient air over an already hot piston/cylinder....but that's all I had at that time.
The holes were actually drilled to mount the new radiator in the front with the new fan, but that fell through due to the fan being 204/220 V as stated, so I thought that having holes (I could put a new plate over them) would actually be a good idea to keep cold air in there slightly longer for more cooling yet allow air to escape enough to create flow. I'm not a scientist, but it makes sense to me.
I do lube with white lithium grease, a very light coating on the pistons. I also have the felt pads that are lubed every third/fourth run, otherwise it gets pushed into the cylinders and becomes a gunky mess, causing the Box to not pump to the needed 4,300PSI.
I normally pump to 4,300PSI so as not to make the Box work harder than needed. I only need that much for a lot of shooting in one day. I typically top-off from around 3,800PSI to 4,300 PSI after every trip (once a week) to keep the Box running as short of a time as I can. Typical run time for that fill is between 45-60 minutes.
That is if it's not too humid. If it's too humid, (even with the pre and post moisture separators) I will use the large tank until it needs a larger top-off and go to a dive shop for that purpose.
I only lube the crank arm bushing when disassembling for reseal. Never had any issues doing it on that interval.
The water pump is now housed in a larger container with a lid to keep mosquitos out, and I will use three, maybe four, Pelican, 1-pound blue ice blocks to cool the water.
Problem at the moment is that weather-wise it's raining making it difficult for me to top-off a tank with high humidity (a rarity in my clime).
One tip that worked extremely well was when the burst disc popped, I found it on the back of the main air block. This meant that a complete disassembly was needed to replace it. I took careful measurements on its location and drilled a 1" hole through the back of the Box to access without removing anything but the burst disc for replacement. I used a deep socket to remove and replace. WAY less work! Amazon sells like 6 discs for not much money, and I believe that they are 7,500PSI.
Mike

 

[Revoman]

AlanMcD --=--

I thank you for the chart and have it downloaded and ready to print now.
Unfortunately, my shop compressor is within 4 feet of the Box, connected with a coiled plastic line that perhaps has a length of +- 20 feet. Likely not enough to allow the cooling time required per your used length.
It is strange however that I have yet to see/realize any moisture in the low-pressure moisture separator. I have an initial one on the shop compressor's manifold, then a particulate filter, then the sieve moisture filter that has the blue to pink silicate beads within (in pic).
So, I'm not certain that I truly have a moisture issue but have in the distant past before installing the Milton filter bank, seen evidence of moisture when resealing the Box. Although that evidence could possibly have been from over lubing the felts for the pistons, creating liquid gunk at the check valves.
While the silicate has just now turned a slightly in between blue/pink color, I have changed it out, yet still see zero moisture in the filter (I added a small blow-off valve at the bottom to check) and it was completely dry when the media was changed.
Might you have any ideas on that please?
Thank you!

Mike

 

[Revoman]

Thanks again Alan!

I have just added another 30 feet of coiled hose to the run feeding the Box, that totals close to 70 feet now, including the 2 coiled sections.
I too blow out the 20 gallon tank a few time annually, still never get a drop out of that either. Overall, I may have the moisture issue mitigated already, but not going to change the set up unless it does become an issue....not likely.
So, my latest quest is to mitigate any heat issues with the Box, thus the small radiator and water pump. Still needs experimenting and verification that it does cool the cylinders enough to make longevity better between resealing intervals.
ALL good conversations in this thread and thanks to all for commenting/suggesting.

 

[Revoman]

I'm still going to test my little radiator to see if it helps dissipate some of the heat. I have noticed on a hot day, which is very normal in SoCal, the high-pressure moisture separator gets pretty warm, I assume from the heat produced by the pistons/cylinders. Temperature-wise, where I live is in the high 90° to a tad over 100° during the summer. The winter, while cooler, still has many mid-80° days. Those are normally the dry, non-humid days, days that I fill because they are dry.
I was able to at least minorly test my radiator today with water and blue ice. This produced a consistent 57° air temperature inside the Box. This without running the Box, only the fan and water pump. The outside (my garage) ambient temperature was 69° this morning, so at least I have proven to myself that there seems to be merit for cooling purposes.
I also tried slowing the air passing over the cylinders by blocking the holes that I drilled, that made the improvement per the above. I'm sure that there is a happy medium of exhaust holes and I will work toward that soon....there is enough leakage around the Box holes as it is, I was just trying to keep the cool air inside long enough to do the job.
More to follow.

 

[Revoman]

Okay. I went shooting today and thought that this would be my test day.
I set the large tank up for a fill, inserted 4, 1 pound Pelican blue ice packs inside the water reservoir and let her rip. The outside ambient temperature upon start-up was at 81°, the air temperature inside the Box started at 61°, so cooling okay.
I watched the temperature periodically throughout the fill, which took about 50 minutes from 3,900PSI to 4,300PSI. It was rising of course.
Once the Box shut itself off, I turned off the fan and radiator to see what the air temperature was without the cooling aid, registered 105°.
I then turned the fan and radiator back on and the temperature dropped to 82°.
During the cooling down process, taking about 10 minutes, the temperature continued to drop to 70°, then stop.
After shutting everything down and removing the 4 pounds of blue ice, it was all melted, total liquid. This tells me that I need a larger heat sink in order to keep up with the ambient temperature when it's hot, like 85°. I'm using a small, insulated cooler for the water and ice by the way, but the cooler isn't the best with only about a half-inch of insulation on the sides, none on bottom or top.
I believe that this little experiment actually worked rather well considering the 85° ambient temperature and with the added heat load only producing 105° max air inside the Box housing.
I'm gonna stretch this further and see what a larger reservoir and more ice does for me (luckily, I already have the ice for coolers).

 

[Revoman]

jking --=--
Thank you for the interest.
I was able to top-off my tank again today. Different condition weather-wise. Ambient was at 71° this afternoon, humidity at 15% (or lower).
I ran the Box for about 40 minutes to top-off from 3,950PSI to 4,300PSI. Starting temperature in the Box was a cool 61°.
Using a larger blue ice, plus reducing the amount of water to keep the tank cooler, it didn't melt as fast and kept the temperature inside the Box at a cool 95° to fill end.
Understanding that the ambient temperature was only 71° versus the above 85°, it seems to work rather well.
More to come, I enjoy experimenting!

 

[Revoman]

The latest on the Shoebox cooling radiator:
Today the weather was around 80° outside, 78° inside my garage.
Temperature inside the Box and Cylinders, the same at 78°.
Cranked up the Box and ran it with the cooling radiator water and ran it for 45 minutes to top of a Great White with a starting pressure of 4,150PSI.
Ending ambient temperature inside garage at 80°. Inside Box air at 82°, Cylinder temperature at 108°.
All with a humidity of 15% (that’s as low as my meter will go, it was likely more like 10% humidity).
I’m pretty happy with the way the temperatures have been behaving as it also allows me to top off at higher PSI without too much heat being generated.

 

[jking]

Sounds like a great improvement. I try to plan on running my compressors on the cooler days and with lower humidity. I live in the SE corner of NM so the humidity isn't an issue anyway. I did install the 13-cog motor pulley and I really like the speed it's traveling now. Before it was running so fast that I thought it was going to come apart at any moment (like it did once in the past). It seems way more relaxed for sure.

 

[AlanMcD]

If you really want the cylinders to run cooler, that smaller motor pulley will make a big difference. I run them on mine, and with the cover off and a fan blowing over the unit they never seem to get above 85° F, even after running for long stretches of time filling a 9L tank. It will slow things down and thus take longer for fills, but you'll get lower temperatures and lower loads on the bearings, which should greatly increase the longevity of the unit. OCO labs does sell them as a replacement part on their website, but you will have to contact them by e-mail as they don't have online ordering.

 

[Revoman]

AlanMcD --=--
Thank you for the insights using the 13 tooth cog.
I happen to have a couple of those from my 'upgrade' F-8 to F-10. I have also contacted Zack at OCO many times for other small parts that still work with the Box, he's a nice kid.
I think that I will switch out the cog and give it a go again. The F-10 cog does make the Box seem like it's gonna take off.
Fill time doesn't mean a lot to me, I'm good with a slow fill.
MIke

 

[Revoman]

Update.

I have upgraded the small aquarium pump to a 120GPH rate to pump ice water through my small radiator on the Box.
This seems to work better than anticipated.
I also left the front cover completely closed and the results were much cooler than previously taken.
When leaving the front cover off of the Box, it cools okay, by closing the cover completely, it seems to hold the cool air inside for a longer period and cools even better.
My latest session was yesterday afternoon in 27% humidity conditions, at 95° temperature weather. Leaving the front closed produced a temperature at the large cylinder (generates more heat than the small cylinder) of a mere 100°. Much lower than previously experienced.
This with a new motor belt gear with 15 teeth instead of the 13 tooth original gear, faster, yet much slower than the F-10 21 tooth belt gear (that one is actually scary fast). I also will try an 18 tooth belt pulley at some point when rebuilding is necessary.
A happy camper here!

mike