I tested out my cooling system today.
Room temp 22.5C
Cool down for 30 min. start 21.6C - end 20.9C
Etching at 10ma 35 min. start 20.9C - end 20.0C
Cutting at 10ma 25 min. start 20.2C - end 21.3C
Using an old water cooler that I saved from the trash. Don’t know what its rated cooling is but I obviously can’t cut none stop but engraving should be okay.
Interesting results!
(1) Those etching and cutting numbers are more than adequate. Are you mainly concernd that cutting beyond 30-minutes would be too hot?
(2) During the 30-minute “cool down” the temperature fell less than 1°C. I would expect that end temperature to be a lot lower. (It’s a water cooler!) What accounts for this minor temperature drop? Was the water circulating during “cool down”, and not just cooling the water in the bucket?
(3) Have you considered a small (e.g. 20cm ~8") room fan to blow over the coils? You might be surprised at the performance improvement of the condenser coils with a little breeze blowing over it. Have you measured the coil temperature?
(4) Have you been able to characterize the laser tube output power vs temperature? For example, during a 30-minute etching job, is the power change significant enough that you’d see a change in the results?
I think it is working well for you. I like the temps your getting at this point. However, what is your room temperature? That would be important to know and tell you how well the cooler is working.
IMO - Cooling the water is important and I’ve come to the conclusion that a balanced temperature within the range of 19C to 2and 22C is my goal to hopefully give me a long tube life along with controlling the ma input.
I was just posting as an FYI. I did list the room temp 22.5C. The pump was circulating the whole time. Also, I did have a box fan blowing on the compressor and the coils but not during the initial cool down period. I don’t think the chiller it is running at peak performance. I did rescue it as it was headed to the dump. I would like to put a temp. sensor on the coils to see how cold it is getting.
Blow a fan across the coils and you will significantly reduce the heat gain, or even nullify it.
I meant the cooling coils. Right now I have my thermometer just sticking in the top of the bucket
@Martin_Dillon Your right you did mention the room temp… my mistake.
I should also add that the temperature range I want may not be sustainable depending on the ambient humidity. I wouldn’t want a wet tube.
I like Tim’s idea of adding the fan.
