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Roy Sanders
07-12-2015, 11:51 AM
Well new friends here is my next learning issue.
I was contemplating a chiller. At this moment i rarely fire my laser up; meaning I use it an hour a week. I have a steep learning curve in getting my graphics to come out in raster or even vector the way it looks on screen. Plus, I am a pen turner. I still work full time and have no energy to work in my shop. So in a few months when I am fully retired I will begin my avocation; turning pens and engraving them.

Why do I want to build a water chiller, now or in the future?

Thank you

Roy :confused:

Dave Sheldrake
07-12-2015, 12:27 PM
A 2 degree spread in water temperature will promote higher beam quality and more stable results Roy :)

Even if it doesn't get too hot where you are a good stable temp of 17-19 degrees C will give fantastic results on DC water cooled tubes :)

Roy Sanders
07-12-2015, 12:34 PM
Well that's that. I will begin building my water cooler. My basic plan is to get 1/4 copper tubing and use my tubing bender build a three layer coil. Then buy a used apartment sized fridge, take out the freezer box so the freezer and the cooler are on cavity. Then insert my copper coil into the fridge/freezer, and hook it to my in/out circuit.

My curious mind wants to know; do I place the coil on the inlet side, so I draw water out of the bucket, through the coil, and into the tube? OR? visa versa?

Roy

Bill George
07-12-2015, 12:44 PM
Will a 5 gal bucket fit inside those refrigerators? I have one or two refrigerators like that, but just looked and a smaller rectangle shaped bucket/container might fit. Drilling in the side of those refrigs might be a problem because the condenser coil could be located in the sides or back. That is what I would do.

Dave Sheldrake
07-12-2015, 5:36 PM
Laser - Cooler - Reservoir or you risk thermal shocking the tube, this way you are cooling the bulk supply of water and the temp will stabilise before it hits the tube :)

Ron Gosnell
07-12-2015, 6:07 PM
I totally agree with Dave,

You can get too cold and shock the tube.
My CW5000 works with the ambient air temps and adjusts the water temp accordingly.
That also keeps condensation down by eliminating the dew point.
As the air temps rise and fall the cooler adjusts automatically leaving me something less to worry about.

Gozzie

Bill George
07-12-2015, 7:45 PM
I totally agree with Dave,

You can get too cold and shock the tube.
My CW5000 works with the ambient air temps and adjusts the water temp accordingly.
That also keeps condensation down by eliminating the dew point.
As the air temps rise and fall the cooler adjusts automatically leaving me something less to worry about.

Gozzie

A refrigerated cooler holds the water temperature or CW at a near constant temperature regardless of ambient or other conditions. By turning on the chiller when the machine is first turned on you should avoid thermal shock. You could use the above suggested "bucket in refrigerator" method and just put the temperature sensing tube into the water. You would be better off replacing it with a real temperature control with a remote bulb designed for that purpose.
BTW in Iowa trying to avoid condensation on the tube by adjusting the temperature of the CW is not going to work. We see RH of 70 - 90 % in the summer.

Ron Gosnell
07-12-2015, 8:46 PM
Cw 5000 manual
I guess mine is the newer model. Totally automatic and works great.
Operation status and parameters
adjustment

The new T503 intelligent temperature controller does not need to adjust the
controlling parameters under normal circumstance. It will self-adjust
controlling parameters according to room temperature for meeting equipment
cooling requirements.
The new T504 intelligent temperature controller is selected constant
temperature control mode as factory setting with water temperature at 25
.
User can adjust it as needed.

Here is a link to the manual if anyone is interested http://www.hi-end.ro/upload/files/CW-5000-hiendro.pdf

Gozzie

Dave Sheldrake
07-12-2015, 8:59 PM
Drop the factory setting to 17 on 19 off Gozz, over 23 will shorten the life of widebody tubes in a big way

Roy Sanders
07-12-2015, 10:56 PM
Ok I got the plan. I will build the coil, about three layers deep, and place it into the fridge. Then run the water from the laser (spent side) to the fridge, then to reservoir and then to the inlet side to the tube. I have a new question arise tonight, will put up a new thread/

Thank you for the ideas

Roy

Jeff Body
07-13-2015, 1:34 AM
I hate to say this but you're wasting your time.........

I had been working on a set up just like what you're doing. The problem is refrigerators are not meant to recover fast enough. Think about it...... is there anything you out in a freezer or refrigerator that produces heat?

Your first problem is most of those small fridges the freezer part is the main cooling part. The housing to the freezer part is where the freon flows through so you can't remove it.
My set up consisted of copper coils wrapped in about a 6" diameter with about 6 layer going through the freeze part of the small fridge. This then dropped the water into a 3 gallon bucket located in the main part of the fridge where the pump was located.

This setup worked ok but the problem is the fridge couldn't generate enough cold water to overcome the heat the laser is producing. You gain an advantage because you can start at a colder temp.
For example I could start at about 10*C compared to 25*C before and it did take longer for the temp to raise but even with the setup the temp would raise to 20*C within about 45 min to 1 hour. There's just not enough there.

I completely ditched that whole setup about 4 weeks ago.

Now I'm running a completely different setup and I'm 110% happy with it. I ordered a 1/4hp aquarium chiller and pump. I have water and the pump in a 5 gallon bucket that pumps through the chiller and into the laser. I can hold a rock solid 18*C for hours now. When I'm ready to use the laser it can drop my water temp from 30*C to 18*C in about 45 mins. Once it's there I get a consistent and rock solid 18*C
My 1/4 chiller has about the same BTU as the CW5000.
And it cost me alittle less than what a CW3000 would cost.
I paid a total of $450 for the chiller and pump shipped overnight from amazon.

Good Luck.

Rich Harman
07-13-2015, 5:17 AM
If I didn't have a chiller already and was forced to DIY I think I would use tap water. Take a length of copper pipe and put it inside a PVC pipe. The copper pipe is part of a closed system which flows through the laser tube. Supply some cold water to one end of the PVC pipe so that it continuously flows (trickles) around the copper pipe carrying away the heat. On the other end the water is routed to a drain or outside. The temperature of the tap water will determine how much flow is necessary to maintain the temperature where you want it.

This would work particularly well for me since we have a private well, and the water is quite cold.

Bill George
07-13-2015, 11:11 AM
Its all about BTU's needed, some people on here were using bottled water chillers. Running tap water down the drain here would cost a lot money Here as you not only pay for the gallons, you also pay for an associated sewage fee.

Any refrigerated chiller should be able to hold a set point, automatically.

Rich is lucky to have a well, but factoring in the well pump power use it may not be that economical to run. Unless he is re-using the water for irrigation or to feed the stock tank for his cattle.

Ron Gosnell
07-13-2015, 11:46 AM
Drop the factory setting to 17 on 19 off Gozz, over 23 will shorten the life of widebody tubes in a big way

Thanks Dave. I just read the specs again on my SPT 130watt tube. Water temp 15c - 25c.
I will do as you say get it down to at least 20c. You are one of the smartest guys and I value your opinion.
What would be the ambient room temp that I need to shoot for to keep from condensating the tube. I cant seem to get that through my brain.
That leads me back to an earlier post I had on make up air and the ac unit keeping up.
I am just a hobbyist and there is no need for me to push my tube into an early death . Thanks for all your help and advice.

Gozzie

Bert Kemp
07-13-2015, 12:11 PM
Wouldn't work for me at all as my cold water in the summer is about 85 sometimes hotter, no such thing as a cold shower :D


If I didn't have a chiller already and was forced to DIY I think I would use tap water. Take a length of copper pipe and put it inside a PVC pipe. The copper pipe is part of a closed system which flows through the laser tube. Supply some cold water to one end of the PVC pipe so that it continuously flows (trickles) around the copper pipe carrying away the heat. On the other end the water is routed to a drain or outside. The temperature of the tap water will determine how much flow is necessary to maintain the temperature where you want it.

This would work particularly well for me since we have a private well, and the water is quite cold.

Rich Harman
07-13-2015, 2:24 PM
Rich is lucky to have a well, but factoring in the well pump power use it may not be that economical to run.

We pay about $0.30 per 1,000 gallons in electricity or 0.03 pennies per gallon*. If electricity was 100 times more expensive that would still only be 3 pennies a gallon. I would not expect to use more than a gallon per minute to keep the laser cool - much less I think. That puts my water cost at about 15 cents for a full day.


*1,200W well pump. Two hours to pump 1,000 gallons (1,000 / 9 gal per minute = 111 minutes) uses 2.4 KW hours. At $0.12 per KWH that is 28.8 cents per 1,000 gallons.

Rich Harman
07-13-2015, 2:25 PM
Wouldn't work for me at all as my cold water in the summer is about 85 sometimes hotter, no such thing as a cold shower :D

Yeah, that would be a problem. Our water is about 45 degrees year round.

Bill George
07-13-2015, 5:41 PM
We pay about $0.30 per 1,000 gallons in electricity or 0.03 pennies per gallon*. If electricity was 100 times more expensive that would still only be 3 pennies a gallon. I would not expect to use more than a gallon per minute to keep the laser cool - much less I think. That puts my water cost at about 15 cents for a full day.


*1,200W well pump. Two hours to pump 1,000 gallons (1,000 / 9 gal per minute = 111 minutes) uses 2.4 KW hours. At $0.12 per KWH that is 28.8 cents per 1,000 gallons.

Heck If I had water that cold it could be used for AC. I worked at a old restaurant one time here in town. they had a deep well that was allowed to stay running even after the city moved in. They had a pre-cooling copper coil in the return air of the AC unit that took the well water in and then the discharge of that water was used to feed the water cooled condenser. Not sure where the water went from there, but they could put a tank outside up high and used that water to flush toilets.
It was a pretty trouble free and efficient system, I don't recall ever having to service other than belt and filter changes.

Jerome Stanek
07-13-2015, 6:11 PM
I have seen people use the drinking water coolers like you put the 3 or 5 gallon bottles on. Wally world sell them pretty cheap

Rich Harman
07-13-2015, 6:21 PM
Heck If I had water that cold it could be used for AC...

In the interest of accuracy I measured the temp of my water. At the pump house it is 53 degrees. That's after traveling 250 ft through warm ground from the well. It was 45 at the well a couple years ago when we had it tested before buying the property. Our previous well was over 220ft deep and it's temp was 38 degrees.

I couldn't use it for AC I don't think. That would require a large constant supply - the previous owner had run it dry when filling a pool a few years ago - they put in a 9 gpm restrictor to prevent it happening again but since this well is only 50 feet deep it relies on rainfall to replenish. Towards the end of the summer it might be risky. Our old deep well used an ancient aquifer - 20 gpm all day long with hardly any drawdown.

Bert Kemp
07-13-2015, 6:26 PM
Some here built one with a 99$ water cooler from wally world, can't remember who of how they did it, maybe a search will bring it up.


I have seen people use the drinking water coolers like you put the 3 or 5 gallon bottles on. Wally world sell them pretty cheap

Ian Johnson
07-13-2015, 6:33 PM
I also tried the fridge and it didn't work. I even had a radiator and fan from LightObject that I put into the fridge with the hose running through a hole I drilled into the side and it wasn't enough. I tried a water cooler, but my pump wouldn't fit inside. CW3000 wasn't an option since the space isn't air conditioned and the ambient is often over 80F. Running a loop through the soil wouldn't be good enough since summer time tap water in Southern California is also too warm. I ended up getting an aquarium/hydroponic chiller as well for around $400 and it is perfect.

Jerome Stanek
07-13-2015, 6:51 PM
couldn't you use it like a ground source heat pump circulate the water through the system and back to the well

Rich Harman
07-13-2015, 7:07 PM
couldn't you use it like a ground source heat pump circulate the water through the system and back to the well

Yes, that would work - if not for it being illegal to do so.

Keith Winter
10-22-2015, 6:25 PM
I know an old thread here...

I read the 17-19c you posted Dave which is right where I have my water temp at 17c. The 5200 water chiller has no issue holding that with my 130watt tube. Is there any advantage to dropping it even lower to 16c, or 15c?

Joe Walmer
10-24-2015, 12:45 PM
This has all been discussed thousands of times for over ten years now. PC water cooling is a huge business with millions of users worldwide. Anything and I mean anything you can imagine has been done and tried. The old fridge, window air conditioner, bags if ice, etc you name it. What has it come down to? Unless you plan on going subzero cooling there is no real need to "Chill" water cooling. And most importantly using even a large home freezer does not work right and is less effective than a radiator and pump.

Basically type in PC water cooling and check out the thousands of videos on youtube or hundreds of stores that sell the parts. Finally pulling the trigger on a Glass Tube machine I just bought a 240mm radiator and a pump and a little reservoir. I have tons of pc fans here some that can blow up to 240cfm a piece.

So to put that in perspective the cw-3000 at 300$ I could buy 3-4 large PC cooling radiators and have enough power for 300$ to cool a small car engine let alone a 40w laser. But at the same time the cw-3000 itself I trust way less than what you can build for 100$ in pc water cooling terms. In fact for 100$ you dont even need a reservoir it would cool so fast you dont need one. It will keep the laser water at room temp or 3-5 degrees less. And if you had 500$ like the cw-5000 I would say you could build one literally 20 times more powerful out of PC radiators and 120mm fans.

All you have to do is type in "water cooling" into a google image search and you will see these people are completely obsessed with cooling and just as serious about the science.