I have a SuperPID on my router, so often the router itself isn’t that loud (running slower) by once you throw an end mill on and start grinding through ply then yeah…
1 Like
Toss a piece of bacon in with every engrave… neighbors will never complain about any exhaust odors… 
6 Likes
I’ve been looking at low noise external blowers as one solution should exhaust noise be a problem. Can any of the PRUs comment on how difficult it might be to disable the internal GF blower so that a suction hose for external blower can be attached at the GF vent outlet?
It’s a closed system. I’d have to take things apart to see. And I promised not to do that. Besides voiding your warranty, it’s not likely to work correctly as it’s been designed with the flow characteristics of the stock unit. You’d also likely need to modify the air intake openings to make up sufficient replacement air. No telling what kind of sensors might be in there that would then decide to disable the laser because it wasn’t getting the correct signals from the exhaust.
If you’re concerned about the noise, it would be easier to open up the exhaust after it’s out of the GF. Get a 4x6 or 4x8 adapter and then attach the larger pipe - putting the same amount of air into the larger diameter pipe which will reduce the velocity and the sound. By a lot since the volume is going up by a cubed factor as the diameter goes up.
4 Likes
Thanks @jamesdhatch - I understand about not taking your PRU apart and wouldn’t ask you to do that. Good idea on bushing up to a larger hose. I’ve been trying to research the subject of blower size, duct size, noise, and pressure drop a bit but haven’t found the Holy Grail yet.
I’m installing a dust collection system in our local MakerSpace. The main ductwork is 8" and that’s what gets hooked to the vacuum/dust collection unit. It gets downsized to 6" for the verticals to the machines and to 4 at the blast gates and then to whatever the machine takes right next to the machine. That way the most restriction is closest to the machine.
There’s a lot of info on the effect of piping diameter on airflow if you dig into shop dust collection systems. Lots more of that out there than laser exhaust info when you’re Googling 
I used that info when I was modding one of my lasers - opened up the exhaust but needed to add intake air capacity in order to take advantage of the improved exhaust capacity over what the machine came with.
3 Likes
Good idea - I’d been Googling on dryer ducting and wood shop duct searches sound like they would be a lot more productive.
The volume of a cylinder only goes up with the square of the diameter, but I am sure you already know that.
It might be worth considering laminar flow through a pipe, and its relationship with the diameter.
This particular case, with fans involved, and a relatively short length compared with its diameter would be more difficult to calculate, but any increase in diameter will have a considerable reduction in the resistance to the flow of air through it.
Just my 2 cents worth of basic physics.
1 Like
I believe pressure is proportional to the inverse forth power of diameter, so I am not denying a bigger pipe is very advantageous, just being pedantic about maths.
2 Likes
You and me both
John
Correct. Typo (vs spheres which are cubed).
Flow through the pipe is also affected by the material. Flexy hose churns the airflow, straight metal or PVC pipe is much smoother so disrupts the air less.
Yes. But then my basic physics didn’t get beyond laminar flow 
2 Likes
Larger duct is not always a good solution, as larger ducting will also reduce the air velocity within the duct. This is a good thing for making a quiet HVAC system in an office or home, not a good thing when the intent is fume or particulate extraction.
3 Likes
quite true, you drop the velocity and the suspended particles don’t move on out either.
YUM! looks delicous
@dan I agree looking at the screen pictures and the out vent that is allot of stuff to capture in the filter makes me think the filter could be a very short life item. or is it constructed in such a way that there is a pre filter that we can remove and or vacuum off or shake out side etc… before it gets to the chemical safe to breath air filter etc…
2 Likes
Im hoping this is the case
4 Likes
hoping heck I’m praying, bmw wants like 200$ at least once a year for my interior filters… ya I take those off and vacuum them until they fall apart
so ya I am praying its a multi stage and at a minimum stage one and hopefully stage 2 are removable and vacuum / shake / whatever may need be
1 Like
I buy 'em off Amazon for my X-1 and put them in myself.
4 Likes