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!
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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?
laughed so hard my stomach hurts 
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While it won’t bring it to straight/smooth resistance/turbulence levels, the inside will have less square inch/foot exposed than an uncompressed flex tube. It might have a small percentage of less diameter, but with less exposed ridges and creases, air will flow with less resistance and turbulence (like unmaintained dirt irrigation ditches versus dirt ditches that are cleaned out of plants, rocks, garbage and the sides are scrapped “smooth”).
While smooth concrete ditches are optimal, dirt ditches can work well when minimizing resistance/turbulence.
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Another interesting question. As the duct is compresses, the resistance goes up, but eventually, the folds come together they may possibly have lower resistance!
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We get it, you vape.
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