Spoke to someone who has worked with CO2 lasers and he thinks that the optics of the cutter may have there life segnifgntly shortend by the damp in the space. As some of the lens meterals used are hydroscopic .
If this is true we may need to redesign the space with a small room with a dehumidifier in it to house the cutter , witch would reopen the room in a room debate…
o joy.
He also said that if the burn on the lens is caused by %RH , it can be refinished at a reasonable cost at a place he has used in his home country.
Dehumidifier. A big enough one.
If it turns out to be correct that the lrns absorbs water , we may have to build a new room for the cutter so we don’t need an enormous dehumidifier.
Redesigning the space at very short notice…
Any guide on acceptable relative humidity value?
If it’s just the lens then keeping it in a box with silica gel or equivalent when not in use would solve it?
This ‘loading and unloading’ the lens bit would probably be a good way of enforcing the ‘check the lens’ policy as well.
A box with silica gel seems to me like the most straight forward solution, rather than redesigning the space.
Also, I’m betting on the RH going down a fair bit once the construction work is done, and the heat exchanger is in place.
I was going to attack it with some iron oxide and mirror polish in the new year to see if that would have any real effect.
Let’s find out if this bloke is right that way we get a longer cutting lens for very little money
We need to ask trotec and I have no idea about what the internal optics are made from.
In general, the following applies:
The following conditions are ideal for Trotec laser devices:
Room temperature between +15 °C and +25 °C (59 °F – 82 °F)
Relative humidity between 40% and 70%
You should also protect the device from direct sunlight.
Problems in winter
In winter, overnight temperatures may happen to drop below the recommended conditions. This can lead to condensation in the laser tube and thus to damage. In addition, greases and oils can harden, affecting the mechanical parts.
From the trotec sight
Condensation anywhere in the mechanism would seem to cause trouble , maybe we should stop using it until we can call trotec .
Let’s hope so its hopeless in there at the moment
Cleaning fluid from a camera store or eyeglass shop will contain water which will harm the lens coating.
Again from the trotec sight.
Its sopping in the space at the moment
I moved the temperature sensor last week off of the roof of the toilet, instead to the wall near the internet rack, this means it’s now measuring more accurately what the space temperature is because it’s not wrapped up with LEDs or above peoples heads in the ceiling where the heat rises to.
Given the relatively quiet week this might not be the best, but the values are:
The absolute lowest in the last 7 days was Christmas Day at 14:00 when it dropped to 14.3ºC in the space, and the average was between 16ºC and 14.5ºC.
As for the humidity that is pretty consistently between 70-75% with the exception of a few huge drops, likely correlated with the door being propped open based on the door/shutter access logs.
The patterns around people using the space are quite pronounced, you can even see how lack of use over Christmas has caused the temperature to drop in the space quite considerably and come back up after.
One issue myself and another member experienced the other day is people holding the door open, we were both talking on the sofa and it went from comfortably warm to reaching for coats because someone who’ll remain nameless wanted to smoke and talk to someone, by standing outside with the door wide open. Obviously this is not ideal as it makes people cold, but also blows the fumes back in.
In the old space we had an alarm to annoy people into closing the door, maybe we should reinstate this feature?
It looks like having heating would be a good idea for the benefit of the laser cutter, but Joe has mentioned repeatedly that the bigger issue is humidity, however until the lining is done, it’s hard to know what it will be like in the space.
Can we look at hiring a dehumidifier as this will heat the space up as well?
I say yes to a dehumidifier asap.
The construction of the wall is adding to the humidity via gauging water and members’ sweat…
Heat exchanger should get looked at. Maybe @joeatkin2 and I will have a look into rigging something up?
Can’t do much buy myself , no power tools
How about if everyone started picking up old estate agents signs .20 should be enough
There is one in Elephant & Castle outside my office that I can’t get to but it’s yours if you can get it!
According to this calculator, we need about 30l/day to keep the space dry.
This one would do. £170. Hire of a similar machine is around £40/week so it makes sense to buy. I need one for my house as well, so am happy to buy and deliver to the space. Any objections?
Sounds like a wise investment!
Good plan , should keep it warm as well