I want to avoid blowing the warm air out of my workshop, i.e. wasting energy when heating the building with large efforts. The heating won’t compensate that in winter.
I am confident to install a thin extrem flexible hose directly over the laser nozzle and suck off the steam directly, so I’m reducing large air flow.
I tried a standard vacuum cleaner close to the nozzle, works fine.
This hopefully avoids also covering the inside and mirrors with smoke deposits on the long run.
a) I might use some kind of good air filter, carbon/fine filter like for welding, got one
b) I could use a heat exchanger, but this will probably clog soon with the smoke deposits.
Any experience with that?
I did not cut through the material yet, still installing everything. How much of the smoke is getting blow out from the material to the underside? Will I need an additional suction there/from the general volume of the cutting area?
Depending on your production volume, it is not enough to just capture the smoke from the top, in fact most smoke occurs on the underside, with correct cutting operation.
Filter, we have all tried, if you have endless financial resources it is possible, otherwise it does not work well in my experience.
You can reduce heat loss by having a tightly closed box around your machine, but then your intake air must be adjusted to your exhaust.
I physically close my exhaust duct, otherwise I get drafts in the workshop when I am not using the lasers.
I had the same issue in my shop. When I upgraded to a 48 watt diode, there was so much smoke generated that I ordered a Fumeclear 2004 for smoke extraction/filtering.
Used it yesterday when outdoor air was about -14 degrees F. With the laser raised up to accommodate a cutting board longer than the laser frame, With the Fumeclear sucking the smoke, no smoke escaped from the gap under the laser frame.
If there is more smoke on the underside as I thought, I will build a box under the honeycomb plate and attach a hose there, too. If you catch smoke right where it occurs, you don’t need much air flow.
First thought was to build a rope system to force the hose to follow the laser underneath, but that’s quite some ado.
Problem is, that most of the honeycomb will not be covered/closed, so the smoke will probably rise around the workpiece?
The filter is a thing…I might use my welding air cleaner first to see what happens. It has Goretex filters and is built for that…but might be clogged soon. Current ideas are with plywood.
Maybe a water gas cleaner? That’s not difficult, just a barrel with the intake reaching under water. It will bubble, maybe I need a diffusor.
But whre do I disppose the extremely dirty water then…it will contain all kinds of plastic cutting gas and stuff…dry it and give it to the waste deposit?
Without being an expert in it, I think that would be the best solution - if the space is there. The solids can be settled in 2 or 3 sludge tanks with natural overflow and will not take up much space from a laser when the first ones are converted into solids again.
It reminds me of exhaust gas exchanges from the small cogeneration plant I worked on, here the solids were mechanically separated in the liquid filter system and backwashed.. the last rinse was through sawdust to catch small particles, it worked amazingly well.
That might be the final solution - I just like to have backups in mind when I do the effort of the hosing.
For the start, the welding vac will do it.
The bigger problem is the underside. I will probably build a stack of fixed apertures like “man vac cleaners besides each other” and hope that the vac inhales enough.
Another weird idea for later was to build an x-y- mover below the table with two additional steppers parallel to the two movement steppers (the circuits have enough power) which is only dragging a flexible hose. Doesn’t have to be too accurate for that.
It’s also that the workshop is a living area and I can’t (and won’t) pollute the place with oddly smelling smoke.
Sounds a bit overengineered
A conical funnel, like in a sandblaster container, mounted directly under the machine bed with an exhaust connected to the end of the cone, will also do. To increase the effect, you can cover the area of the honeycomb that is not being used with loose plates. For pure engraving jobs, a bypass is needed so that you can ventilate from above.
(However, some fine-mesh wire must also be installed, or the smaller parts will end up in the propeller/impeller of the exhaust.)
I don’t think I will cut such fine parts, but good hint.
The cone idea will not do more than a square box, I have to see where the smoke is going. I’s assume it spreads to anywhere if I don’t catch it close to the nozzle?
Overengineering, yet, it is. It shall be. Because I want to avoid the usual “suck it out of the whole machine and blow it out of the workshop” thing and there it get’s complicated. That’s why professional machines are way more expensive, with employees (or just the precious me) you are not allowed to fill the workspace with poisonos fumes and if you want to have fairly warm workshop…I can’t afford to have the warm air beeing lost.
The first cuts in plastic showed me that this a task I have to solve.
And I need a fine parts filter on the long run, too…
Acrylic is the worst in terms of smell, the bitter and sharp smell lingers in the workshop for a long time. The condensate from acrylic is also not to be forgotten, it settles on colder parts of the extraction and takes up a lot of space over time.
PS, this material has also very quickly “destroyed” my carbon filter (1 kg), however the filter was able to do the job until the very end.
