Lasers and Humidity

[Bert Kemp]

I'm thinking of moving to a more humid area, I'm wondering if its easier and cheaper to dehumidify the laser room or to a/c it.

[Kev Williams]

A dehumidifier just removes humidity, an AC unit does the same thing but you get the benefit of the cool air. Unless you don't need the cool air. What to do with the cool air when you don't need it is the question...

[David Somers]

How about just not moving to a more humid area? (grin)

Seattle can be fairly humid in the winter. Though not horribly. Summers are usually quite dry.
In the fall/winter/spring I heat my garage when I work in it, and since it is attached to the house it generally stays at ambient temp otherwise, 40 to 45 at night? I have a small goldenrod heater that I put in the bottom of the machine and that generates enough heat to eliminate any condensation in the machine. It is in the main cabinet, not in the tube space. It keeps the machine a bit higher than ambient temp. I also made an insulated cover, kind of like you would use on an outdoor BBQ grill when not in use? The inside layer is a fuzzy kind of material so you do not have plastic up agaist the metal directly, holding moisture against it. I use that more as a tool to keep dust out when I am working on other machines in the shop. But it also helps to hold a bit of that heat in from the Golden Rod. The golden Rod is very low power consumption and perhaps safer than a light bulb left running in the machine? That is just a guess on my part of course. Anecdotal only.

In a humid location in summer with warmer temps I might be tempted to use a golden rod in there when the machine is not in use. Again, you will be using it in the main cabinet, not in the tube space. Again, keeping the temp a few degrees above ambient can really go a long way to prevent condensation. An alternative might be to keep a small fan in it like a computer fan to keep air moving through the unit when it is unused. That will also help with condensation. Keep it dust free inside. Dust will hold moisture against the metal and cause problems over time.

You got the CW5000 chiller with that right? So you are not too worried about that being able to keep the tube cool enough. But you might find the temp in the work space more comfortable with AC, or a dehumidifier that can vent its heat outside (which makes it basically an AC unit really) So that may be justification to get an AC unit by itself?

Have you asked the good folks at Rabbit what they would like to see?

I assume you are considering moving to Seattle or the Pacific Northwest Bert!!! Instant bunch of friends here (or at least 1 friend and his wife and dog!! <grin>) A great environment, mild climate, spectacular scenery with ocean and rivers and lakes and mountains and all kinds o stuff. And don't let our propaganda fool you. It doesn't rain here anywhere near as much as is claimed. 36 inches or so annually? Come on out and stay with us while you pick a house! <seriously...come on out!! <grin>)

Dave....not a member of the Seattle Chamber of Commerce....Somers

PS....in our old boat, I have completely eliminated problems with moisture and mold in her, even when shut up over the winter, by using a dehumidifier running on low. I also keep a small fan running in the forward cabin. Before I did that I kept it under control with the use of golden rod heaters and small fans around the boat. The dehumidifier did the best though.

Regarding the dust. In my old NPS IT job in Hawaii I covered a few offices that were not air conditioned and were by the water. One site on Maui had no electricity except an undersized solar system. Its computers were turned off when not in immediate use. Shortly after I started working their someone came over from that site and brought a floppy disk drive with them that was not working. I looked inside it and saw rust? I banged it on my palm and got an amazing amount of rust tumbling out. I looked up the purchase date and the machine was less than a year old? That was when I found out what office it was in and learned about the power situation. Next time I traveled out there I checked all their machines and they were all like that. Inside, each machine had a heavy coating of dust on the circuit boards and in the drive bays. The dust was quite moist, collecting moisture that would condense on the cooling parts each time the machine was shut down, and holding moisture and crystallized salt against the metal in the machine. The board's surface wires were almost corroded completely away and could be brushed away with your finger. Needless to say they don't run well after doing that. He he. I switched them over to laptops from those desktops. Much less power consumption and well within their solar system capacity for overnight storage. Now the machines could trickle charge all night and stay a touch above ambient temperature (like I alluded to above) and between that and keeping them blown free of dust they lasted for years. So that is why I made the suggestions above about a very mild heat source and keeping dust out.

[Keith Winter]

DeHumidifier is cheaper hands down. If you ac you might still have to get a dehumidifier. It's about 60% humidity even with ac running where we live. Dehumidifier in addition to the ac brings it down to about 40%

[Jack Clague]

I'm lucky we are a dry country and humidity is usually low but I'm going to struggle in summer where I live, we usually get one week of 41degc days, as my laser is going to be in my garage I need to keep the ambient temperature around the machine to 30deg or less, I'll probably have to reroute the house central aircon unit into the garage for those days

[Bert Kemp]

Thanks Dave appreciate the offer but I'm going to the opposite coast, NH. Temo today wae around 83 90% humidity dew point somewhere around 70, I like to run my laser around 68 so I'd get condensation on the tube. Personalty I don't need the AC if I have a couple fans blowing in my direction, and I don't need the expense of running a/c just for the laser. So I guess if I do make the move I'll have a room just for the laser and since you guys say its cheaper to dehumidify I'll go that route, doesn't make sense to run ac just for the laser, and if the DH is not enough well then I'll do what I gotta do

[Joe Pelonio]

The better (and bigger) window AC units have a dehumidify setting, I have one in my shop for the cold, damp days or the hot summer days. Mine is 8,000 BTUs for a 400 sf room.

[Ron Gosnell]

New Hampshire, You may want to add a little heat to that :)

Gozzie


Thanks Dave appreciate the offer but I'm going to the opposite coast, NH. Temo today wae around 83 90% humidity dew point somewhere around 70, I like to run my laser around 68 so I'd get condensation on the tube. Personalty I don't need the AC if I have a couple fans blowing in my direction, and I don't need the expense of running a/c just for the laser. So I guess if I do make the move I'll have a room just for the laser and since you guys say its cheaper to dehumidify I'll go that route, doesn't make sense to run ac just for the laser, and if the DH is not enough well then I'll do what I gotta do

[Ron Gosnell]

I asked about doing just that but these folks steered me away from it.
They said it wasn't a good idea to tie into the house so I got a nice wall unit with heat and ac. It works really well.

Gozzie


I'm lucky we are a dry country and humidity is usually low but I'm going to struggle in summer where I live, we usually get one week of 41degc days, as my laser is going to be in my garage I need to keep the ambient temperature around the machine to 30deg or less, I'll probably have to reroute the house central aircon unit into the garage for those days

[Jerome Stanek]

Humidity is bot as important as the dew point.

[Mike Null]

I've been operating lasers for 18 years in my basement. I use the central air and heating for my basement and it works just fine. I have a dehumidifier but don't need it.

[Bert Kemp]

Can it be set to run DH only? Then if I gets really hot I might turn on ac


The better (and bigger) window AC units have a dehumidify setting, I have one in my shop for the cold, damp days or the hot summer days. Mine is 8,000 BTUs for a 400 sf room.

[Bert Kemp]

Right with the humidity here and cold water to my tube I reach the dew point pretty easily, that's why I'm thinking a DH is more important then A/C. I won't have central air, I lived in NH most of my life and never had or needed A/C or a DH for that matter but now having a sensitive laser I have to consider something .


Humidity is bot as important as the dew point.

[Matt McCoy]

Hey Bert: I have had a few lasers in different spaces here in Dallas/Fort Worth, where it has get pretty hot and humid during the summer. I've used water buckets, CW-3000, and now a CW-5000. I have the chiller maintaining a 23 degree temp in an unconditioned space and do not get condensation on the tube. Anything lower than that and it starts to form this time of year. I'm sure this is no help for NH, but throwing it out there in case someone is interested.

[Jeff Body]

Since my laser is in the garage I don't have A/C.
I also live in FL where it's hot and humid.

I've have found that if I look up what the dew point is and set my chill 1* higher I don't have a problem.

[Jerome Stanek]

My unit is in my shop in northern Ohio and have High humidity and it doesn't affect my laser just me.

[Bill George]

Both my lasers the Chinese one and current machine set in my insulated heated and cooled shop/garage, The AC is only on when I need it and its a 18.000 Btu window unit, No problems with either machine. Yes in Iowa we have 97 Deg and 80- 90% RH days. But the window unit seems to handle it just fine.

[Bert Kemp]

Well its like I mentioned that I'd like to keep the cost down and a/c is expensive, and some one mentioned a DH is a lot cheaper to run. I'll do both if necessary but hopefully a good DH will do the job.
Thanks for all the replies.


Both my lasers the Chinese one and current machine set in my insulated heated and cooled shop/garage, The AC is only on when I need it and its a 18.000 Btu window unit, No problems with either machine. Yes in Iowa we have 97 Deg and 80- 90% RH days. But the window unit seems to handle it just fine.

[Kev Williams]

FWIW, I've had my Triumph nearly 2 years now (with just a 3000 cooler) and in the summer months my water temp averages 24 to 25c (75-77°f) and I've never noticed any engraving/cutting difference at those temps vs running it at 15c (59f) in the cold months. I think most would agree around 74°f would never hurt the tube, and hitting that as a dewpoint temp you're looking at very high humidity...

[Bert Kemp]

Thanks Kev I'm going to see what happens at higher temps. I've always run around 68 to 70 maybe 71 but never higher. I'll have to try it up around 75 and see if I lose any cutting power.


FWIW, I've had my Triumph nearly 2 years now (with just a 3000 cooler) and in the summer months my water temp averages 24 to 25c (75-77°f) and I've never noticed any engraving/cutting difference at those temps vs running it at 15c (59f) in the cold months. I think most would agree around 74°f would never hurt the tube, and hitting that as a dewpoint temp you're looking at very high humidity...