Needing some venting feedback

I’ve ordered the filter with my GF, but since it was announced that it will be shipped later that the laser, I’ve decided to set up a vent system.
I’m building my office in our basement and while I’m in the process, I may as well set it up. The hose will end up approx 17 feet to reach the best area for the vent. I’ve already purchased an in-line fan to help.
My question is… Is this too long and since it’s in the basement, is it a problem to have the hose up along the joist. My wife and are newbies, but when I saw the GF, I fell in love and want to explode my small graphics business to hopefully a full time career.
Thanks for feedback, I’ve learned so much already from everyone.

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It’s not like the vent will get warm to the touch or anything. So where it runs isn’t an issue. But the length? 17ft is twice the design length. Make sure you accounted for going up, over and back down to a vent. 17ft sometimes ends up being 30 ft.

Need to have sufficient exhaust airflow. I remember reading a post where dan said the unit had sensors that would determine if the exhaust port was blocked. Can’t think of why too much air flow would be a problem but then again I wasn’t on the design team.

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Thanks! I did take that into account, I may be a foot +/- off, and did get the fan to help.
I recently read that it wasn’t good to have the hose above the GF but really don’t have a choice being in the basement.
Thanks for the advice!

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My dryer hose goes up to reach ground level and so does my Glowforge vent. The GF particulate will be finer and lighter than dryer lint and guessing it will vent fine with sufficient air flow. You could look inside after a month or so just to check.

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Great idea! Thanks!

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If you can make the vent out of solid (smooth) ducting, then you can go about three times the distance you can with corrugated duct. Remember that every bend adds a bunch of effective length, though.

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Thanks! That’s great to know and very do-able!

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Absolutely. the corrugated dryer vent creates a lot of turbulence.

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Thanks!

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Indeed. We keep the exhaust ports of our office Glowforge units covered when they’re not hooked up to a filter. If you try to print with one by accident, it detects the obstruction and just powers down again immediately.

Note that we can’t support nonstandard venting arrangements, though, and they can cause problems.

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Have you got a reference for that? It seems a big difference for a 4" pipe. I would also expect it depends on the flow rate. I.e. lower flow rates to be affected less by corrugations.

This was my post and reference about 10 days ago. I agree, all of those factors would apply, and it’s certainly not my area of expertise.

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Its going to be a variable amount, as airflow will change based on how much its stretched out.

After some more research I’ve found that

“Non-metallic flexible duct pressure losses, at maximum stretch, fall within ±2% of rigid sheet metal losses. At compression values over 4%, non-metallic flexible duct exhibits 2 to 10 times increased pressure losses over sheet metal.”

So, yes, the amount you stretch out the flexible duct makes a BIG difference!

www.mmmfg.com/pdfs/060601_cc-kw_ducttechpaper.pdf

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Where could I find the standards for the gf venting?

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I just want to mention that I have destroyed flexible ducting by trying to stretch it too far while trying to maximize airflow. Once that little wire starts tearing through it can be over for that length of ducting. If you go with the rigid-pipe style, you may be purchasing it as flat stock with a crimped end, that you assemble. If this is the case, use aluminum duct-sealing tape (not duck tape) along every seam. It is a lot easier to use the tape while you are installing fresh, clean ducting than it is to go back later and try to put it on installed ducting with little clearance and a coating of dust.

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Thought about rigid ducting but need to use flexible so that I can pull the unit away from the wall when using a Pro. Don’t have it yet though.

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Try to keep the flex as short as it can be functionally for you. 8 to 10 foot is a bit long when used with fixed/solid ducting.

Also, the additional length can be compressed and wrapped with something to keep it compressed. If you wrap it with stiff material (that stays closed with Velco straps), then you can unwrap it when you need more length and re-compress as needed.

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I just plan to plant my lips right up to that vent hole, kiss that GF like a long lost love, and suck every little bit of smoke like it’s a 3 foot electronic cigarette. Draaaaaaaag for all I’m worth, puff it out the window in giant smoke rings…

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Interesting question. How does the increase in air resistance due to the compression of the flex duct compare to the decrease due to the shorter length?