I keep getting smoke in the room I’m in, I upgraded the fan to the 6" most recommend. Tried removing the stock fan, taping off some larger holes, tried opening up doors on the laser, moving the fan to right at the outlet. I stopped short of buying yet an even bigger fan, which now seems like it’s going to be the next option, but I really don’t want to dump even more money. Anyway, nothing seemed to help. Got me wondering if my air assist pressure is too high and it is blowing the smoke out of any orifice in the way. Started searching, and came across the post above.
Toward the end, @jkwilborn mentions various pressures for different situations.
Questions: 1) I would assume to achieve these different pressures, it would have to be done just by hand when the greater need dictates the requirement. Without getting too complex of a setup, I’m not sure how it would switch mid program, so I’m assuming it’s just like I said, a manual switch before the project starts.
Anyone that cares to weigh in on the air always on vs. just with cutting? I know it is more important for cutting, but I think Jack even mentions in the above, if you don’t have the constant flow, you likely have dust caking up your lens.
Your preferred pressure for say plywood or a hardwood, or both , or any materials you like.
Any further smoke removal tips? I know people were saying not to have any 90 degree bends in the line, but that doesn’t seem realistic.
I use the fan for most engraving and cutting. Pretty much for the reasons you mentioned above. You do get darker engraving when you turn the air off, but you also get flare ups, and your lens gets dirty a lot faster.
I have read that you should keep your air pressure at around 10psi. I have min set at 20-25 psi, and I prefer the results I get. To everyone his own, huh?
I would suggest turning the air assist off on something that is really dirty (MDF maybe), and then inspect your machine while it is cutting and try to determine where your leakage is occurring. I have my laser out in my workshop, where leakage isn’t as important as if it were in my home living space, but I detect very little leakage when the fan is on.
Dan, that’s the one I purchased as well. OK, well, thanks for your input, it helps! I run at about 20-25 also, but I have flow controls I think I’m going to toy around with. They were wide open before, going to see what reduced flow produces. Again, many thanks for your input!
Most of us use the advanced air assist system to select air pressure. This is limited to Ruida as far as I know…
It uses the Status and Wind sinks from the Ruida. When the machine is in run mode, the Status pin sinks current. When the air assist option selected on the layer and it’s running that layer, the Wind output sinks current. You do have to configure the Ruida to enable the Wind output.
With the basic air assist, it turns on the air, via a solenoid, from the compressor. This goes through a restrictor to lower the pressure. This gives you low pressure air anytime the machine is in run mode.
When Wind becomes active, it will activate another solenoid bypassing the restrictor, giving full pressure to the head.
I run less then 5lbs when I engrave… I have to put a lid with water in it to set it low enough. When I cut, I select air assist, I run 60lbs… At least for wood and similar products… Low pressure for cutting acrylic… Air assist makes a serious difference.
Not sure if you can apply this to your controller… Not sure which controller you have in that machine.
Jack, just to be clear, you are suggesting that that alone is under powered? Dear lord, how do you get anything bigger in there, do you have to hack out the 6” piping and put an 8”/10”?! I feel like I’m going to try a 4” version I bought for my smaller laser in conjunction with the 6, see if it helps any. I’ll just have to create some type of a plenum to come off of the feeder slot on the opposite side or something.
I might have some further questions for you regarding your setup for air assist. Not sure why this is the first I’m hearing of this type of setup.
The fan in the photo moves about 350cfm… I think it’s light, but there aren’t many choices that will allow you to hear, don’t require a larger diameter and at reasonable cost that work well. It’s much better than the original…
I think you need to sit down and watch what happens to the debris flow… make decisions based on that… Nothing is perfect for all jobs.
Here’s an old video that I took cutting out a moose… This is 4. something mm siding or something they had on sale…
This is with the original fan, compressor and the lid is wide open… Watch the smoke… it comes out from under the piece then goes out the back where the vent is. Remember the lid is wide open…
One of the reasons I ditched the honeycomb is it disrupts the air flow …
I prefer my sheet of steel. Low cost, magnetic, I can drill locating holes in it and it pretty much wipes off with a solvent for whatever you’re cutting… Machine doesn’t stink as much either.
!! How is this the first I’m hearing…. I think my controller will be fine, it’s Ruida - RDC6442G-B(EC)
I use Wind for on off with the laser right now. Wasn’t aware of the other option “Status”. I need to review exactly what you are doing. I think I get it, not sure how you gauge what your pressure is after the restrictor since you don’t have a dial. Also, what do you mean by lid with water in it
For engraving light woods or materials, I want so little air flow, I can’t really measure it…
So I take a jar lid or condiment dish, put some water in it, stick the nozzle in the water and adjust for slooow bubbles… Some restrictors are easier to use than other when it comes to adjustments.
If I’m doing slate, I want a little more than that, so I stick my finger on it and feel the pressure…
lol, now I catch you. Yeah that’s pretty scientific
Yes I caught the video thank you! So the smoke direction is heavily influenced by your air assist then… geez, I never would have thought to be honest.
This gives me hope, as ever thanks!
Your pic looks pretty easy but the schematic has me wondering if I’m oversimplifying. Basically two solenoid valves instead of one, one line restricted with a flow control. This one always running when the laser is running by connecting to “STATUS” on the controller and the second running, at a higher pressure, in parallel connected to “WIND” and you have to select “air” in the layer (like I have it now).
I still can’t believe I didn’t know about this. This is actually a really cool feature. You could totally do some really cool stuff with this additional option. Maybe have the music start playing and a disco ball drop out of the ceiling
As usual my friend, the help is appreciated. If I’m ever in your neck of the woods (or you are in mine) I’d love to buy you a drink or 7.
Also, if you aren’t using a honeycomb (I like your idea), you must be using standoffs on the underside. Looks like the cutouts were dropping through and you’d have char marks on the back.
Hi Jack,
It appears that you are using a valve to control your air assist. I am by no means well versed in this (perhaps someone else could chime in) but I believe a valve will reduce the air flow but not pressure. A regulator would be needed to reduce the pressure. Now we get in dynamic pressure vs static pressure which really isn’t my area.
Let’s say you have a compressor putting out say 20 psi and use a valve to reduce the flow down so that bubbles slowly come out of your lid of water. Now you swap out the lid of water with something more restrictive, like honey (I by no means endorse putting honey on your laser head. This is just a thought experiment ). There will still be small bubbles coming out of the honey because the pressure will still be 15psi. It will just take a min or two for the static pressure to build up and the bubbles to start.
So the question becomes, are you trying to reduce the pressure or the flow of air? In the end does it really matter. If it is working for you that’s all that counts.
About everything about lasers are, in the end material related… What’s happening to the material is generally the big concern aside from the machine safety, such as the lifetime of the lens.
If you are engraving, the main idea is lens protection, so a low volume/pressure is usually used.
If you are cutting wood or other materials (except acrylic) you would use a high pressure to supplement the laser cutting by helping to remove the debris left by the lasers cut…
Here is a photo of the nozzles I use, the left for engraving and the right for cutting… Neither is exclusive to engraving or cutting, but the long pointed one with the small hole is going to give you more air speed than the larger hole (along with the smaller supply line)…
I don’t know anyone what knows what pressure their head is exactly. You can see the plumbing and nozzle size will determine what pressure is at the nozzle and what pressure is at the regulation point. They are probably not the same… You would need to measure it at the nozzle.
I use these tubes… so you can have 4 different lens lengths…
This is the 2" configuration… left to cut, right to engrave.
). There will still be small bubbles coming out of the honey because the pressure will still be 15psi. It will just take a min or two for the static pressure to build up and the bubbles to start.
