I am new to laser engraving / cutting and need some guidance.
I have a Sculpfun S30 Pro with Camera which is located next to an external door with a quite powerful fan blowing across the laser bed towards the door. Currently the door is open and as long as the winds blowing in the right direction the atmosphere is reasonably pleasant.
Due to the camera an off-the-shelf enclosure will not work and space is a bit tight.
However, when the wind is blowing in the wrong direction I find myself breathing in some obnoxious fumes which will get much worse when the weather turns and the door has to be closed.
As I cannot vent to the outside I have been considering the purchase of a 300 watt Omtech extractor with four filters which would appear to vent the clean, filtered air back into the room.
Does anyone have any experience of using this unit without an enclosure and allowing it to vent back into the room?
I’ve never owned or used one of those units and beside the cost of effective filtration and filteredness of the air put through it I’m wondering how effective they are without an enclosure.
The main point is the effective suction in a room of a given cubic metres but also with an Air-assist possibly pushing the smoke away from the effective draw zone (that will get smaller in relation to an increasing cutting deck size).
The points you raise are exactly my own concerns which is why I was hoping to contact someone in a similar situation.
I have purposely opted for the most powerful I could find at the cost point as, in theory, 300 watts should be OTT for the purpose particularly when you consider they produce smaller models down to 80 watts.
My thoughts were that when the door is open I can port the fumes outside, without filters and if the weather is inclement I can drop the filters in and port it back into the room.
I took a Cubic area of 2ft (380x380x380mm) = 0.05 Cu Metre.
(Where and at what height is camera located?).
OmTech 467 Cu m/h.
= 2.59 total area air exchange per Minute.
That’s very good.
What design is the cutting deck, clearance below?
I have a channelled cutting deck and the smoke is blown down into those channels and shoots along under the material at speed.
If I had an extractor directly over the job the extractor has to capture the smoke from much further away.
The extractor is most efective within a given area around its intake, and that drops off exponentially as you move away from that intake.
The smoke also has the air assist pushing it further away and the air assist travels away from the effective suction zone as the laser travels around the cutting area.
Extractors can work well when working with the likes of a polishing wheel that does not move from the efective extraction area.
The open atmosphere of the room and air current could make it difficult for the extractor to draw the smoke inward.
Have you looked at the operating db’s of the extractor, a constant drone of a fan could get irritating.
Could you construct a surround that would at least contain and guide the smoke toward the extractors effective area.
Its not so much the tolerability of particulates on any given day, but the longer term effects of exposure.
You may also want to expand the frame size in future or work with more cautionary materials so a worst case scenario plan could be worth considering.
Can you build something lightweight using PVC tubing and black trash bag plastic (or transparent red flexible Mylar) for visibility? You will still need to contain the smoke somewhat for the filter unit to work as you expect.
I think I am going to have to build an enclosure, maybe then I can save some money by getting a lower powered extractor.
The only other posting on this site praises the Omtech 300 but says that, in his opinion, if you want to discharge back into the room you need a unit from Putex.
It probably is the best way forward. I’m working in a large loft with windows at several locations but the smoke generated can be considerable and while tolerable up to a point you’ll soon realise its not a long term option.
Also the enclosure will help with avoiding passing glances of the laser..it just happens.
If you want to discuss ideas/options for enclosure, just post them up.