Extraction Fan System - Ortur Laser Master 2

Hi there,

Recently I purchased the Ortur Laser Master 2 (20w) and now im looking at building a custom enclosure for the engraver, with some sort of fume extraction fan system connected with a flexible hose leading out the window.

Regarding the extraction fan system, can anyone suggest a relatively cheap method, (eg. bathroom extraction fan and would it be enough to expel all fumes)

Also would standard Orange coloured acyrlic block all harmful rays from the laser when looking at it directly?

Thanks in advance everyone. I’m pretty much new to all this stuff.

Orange acrylic will reduce a 5W blue diode to negligible power, but I would still wear safety glasses with any diode, even one in a case. (it’s a 5W diode - 20W is ‘marketing’).

Personally, I prefer ACP - aluminium composite panel - for use as a housing. It slots neatly into 2020 aluminum extrusion, which makes constructing a box simple.

Anything that pulls air will work, but a proper inline duct fan is my preferred choice.

This one is a 4" inline duct fan with variable speed, from AC Infinity - a manufacturer with a decent rep.

https://www.amazon.com/AC-Infinity-RAXIAL-Booster-Controller/dp/B07ZL6FDYG/ref=sr_1_19?dchild=1&keywords=inline+duct+fan&qid=1614567342&sr=8-19

AC infinity can also match it with a carbon filter, ducting, etc. if you need it.
You can buy off-the-shelf 4" duct flanges.

https://www.amazon.com/Connector-Plastic-Straight-Heating-Ventilation/dp/B07WG41SRJ

That is pretty much what I have done with mine. I used 1/4" plywood and used a 120mm computer fan into 4" flexible vinyl ducting. on a calm day it is enough to extract all the fumes, but when the wind blows it doesn’t have enough static pressure to prevent the wind from blowing the air backwards up the ducting and I get puffs of smoke in the room. I will be looking into a fan with more static pressure than an axial fan. I’m thinking of trying a centrifugal fan next. I think what should help with the windy days.

I bought some 12x24" OC3+ tested acrylic sheet just to be sure the acrylic would prevent eye damage. I’m sure it is just run of the mill acrylic, but it is nice to know that it was tested. It was worth the extra $15 for the piece of mind. I still wear glasses if I’m going to be working with reflective material, but I don’t worry about it on non-reflective materials though.

I made this box for a few years, it worked perfectly for me with a small PC fan. For my CO2 laser today I have something that ventilates 1000 more or so

A 25W AC axial fan should have enough oomph to do the job.

A computer fan is <1W

I’m not sure what an ‘OC3+’ rating is, but it’s not that complex - the laser puts out a beam in the 405-455nM wavelength, orange is 585–620nM, so nothing in the 405-455nM range can be transmitted.

If it looks orange to your eyes, it’s diode laser safe. There’s a lot of stuff sold with ‘ratings’ to part people with their money, that is no different to coloured plastic. A simple test is to put something very flammable, like fine rice paper or tissue paper, on the other side of the acrylic and fire it. With clear acrylic it should burn. you can also (as I did when I was less sensible) put your hand on the other side and see if you can feel any warmth.

My ‘laser safe’ glasses are green tinted, which is 550nM.