Ventilation setup

Alright so I know the manual requirements of a maximum of 2 bends and 8’. I’ve also read through the topics here but didn’t quite find what I was looking for.

I’m looking to extend my ventilation line with the addition of an in-line booster fan. In the photo, I’m thinking something like the red line. The X would be the booster fan which is roughly 8’ from the GF. It would be pushing air about another 16’ straight across the ceiling and out a vent. The booster fan is 6” and pushes 402CFM of air. I’m looking for feedback before I set it up because I’m not sure if this is really doable or is unsafe due to the length of the ventilation line.

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Totally doable especially if you use hard pvc pipe instead of flex duct.

Hard pipe has a lot less resistance than flex duct and that fan has plenty of power and airflow sounds like.


That’s a solid plan. DO put the booster as close to the end as possible. That way the entire exhaust run is under negative pressure, and any leaks in the joints will be sucking air in instead of blowing smoke out.
I second @evansd2 suggestion of smooth pipe, less turbulence, and better airflow.
Nice setup, I’m guessing you do leatherwork. :upside_down_face:


Yeah. Put the booster fan all the way at the far end, just before wherever the vent exits the wall. With that length of duct, any pushing of air that’s done from the GF end is going to build up a head of pressure in the duct, and every pin hole and seam in your ductwork will leak smoke. If instead you just run a fan at the far end, it is sucking through the duct not pushing. That means the duct runs at negative pressure relative to ambient. Any holes in the ductwork will draw ambient air in rather than leak smoke out. Disable the fan in the GF when you run a booster.


Definitely use hard PVC/ABS ducting and place the fan at the end of the run.

Makes total sense, thank you! Does it not matter that the booster fan will be ~25’ from the glowforge? Is there a risk posed when running both fans? I was just thinking because of the distance I’d want to use both.

:upside_down_face: caught. I have no idea what I’m doing with this glowforge setup though :joy:.

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Is there a certain rating I need for PVC? or does that not exist that large? I’ve only used smaller piping and it’s like 20 or 40 psi

You will soon! There has been a lot of discussion around leather, the forum search function should give you lots of reading. :sunglasses:

Personally, I would run 4" whatever, and use an adapter to attach to the 6’ fan. A major benefit of a booster is to eliminate the need for the internal 4" fan that runs at 13,000 RPM and is louder than a vacuum. The machine needs around 200 CFM for exhaust, that 6" 420 CFM should be enough for the length and turns in your run.
I would try it without the internal fan, and adapt if needed. As long as you can see the smoke being aggressively pulled to the left you are good.

Seriously, the noise reduction without the internal fan is dramatic!



I actually bought an adapter to bring it from 4” to 6” but I anticipated to use the flexible venting. Apparently 20’ of 6”PVC is $199 :joy:. Yikes. Do you think I shouldn’t even entertain the flexible venting with this setup?

You guys have been so helpful already.

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Lowes has 6-in Dia x 10-ft Schedule 40 PVC Pipe for $37.

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Do you have a SKU you can send me? Everything I find on the Lowe’s site says unavailable near me and unavailable for delivery. (The schedule 40 10’ PVC is $68 for me on Lowe’s site but I still can’t order it.) I’ve also called them and Home Depot but the circumstances the same at both and they have both directed me to another place called Fergusons because they said they don’t carry it. Ferguson sells 6”x20’ for $199.


My lowes doesn’t have 6" for delivery either. They do have 4"x 5’ for $16. I’d think 4" would be sufficient, will be a lot easier to find, and half the price.

Lowes also has this: 4"x10 ’ $12 . Item #187408Model #04550010 This is corrugated on the outside but smooth on the inside, so it should also work fine. I use it for dust collection in my wood shop.


I’d defer to others on this but since pressure isn’t that high, schedule 20 might be good enough for this case. I’ve used in vacuum installs. A bit cheaper.

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Thank you so much! I’m gonna go for it with that one. I did find a few variations but I couldn’t get any of them delivered or picked up across multiple big stores. Who knew it’d be so complicated to find something in that diameter :joy:.

The answer is “it depends”. If the fan on the GF pushes air faster than the fan at the outlet pulls, the GF will evacuate better, but the ducting may leak.

This is actually something that can be calculated, but I don’t have the skills. Whenever I encounter a problem like this at work, there’s always someone I’ve hired who knows how to figure it out and I just have them do it.

Empiricism can solve the problem without math. Just try it and see. :slight_smile:

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I push mine 5’ up then 30’ across the basement with one 6" fan, I used the white drain tile. Works flawlessly. I also use a blast gate that I designed and built for my wood shop to close it off when not in use.



Amazing! It looks great. I’m going to try the same thing today. I appreciate the help!

Now I have shop and tool envy!