You may just have one of the better-sealed houses of all GF owners. 
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Here’s one source that says a 45-degree bend is equal to 2.5 ft of straight pipe. A 90 is equal to 5 ft. It also mentions make-up air, which is a concern particularly if you have a non-sealed source of combustion (non-airtight fireplace or stove, low-efficiency furnace or water heater), or you live in a properly built newer house with an air barrier and sealing.
Dryer Vent Safety
Whole house heat recovery ventilators are the automatic but high initial cost way of providing make-up air. Opening a window is the low initial cost but you-have-to-remember-to-do approach, and if the outside temperature isn’t moderate it will cost to heat or cool that make-up air. There’s no perfect, easy, low-cost solution, it’s simply an aspect of laser operation that you need to accept. As with dust collection for woodworking, once you are part of the community you hear plenty about it, but manufacturers never bother to mention it because they want you to think you can just buy a machine, plug it in, and crank out amazing stuff. Hah! I can only hope there’s a special place with minimal make-up air for the people responsible for such deceptive marketing.
It’s not something to take lightly, but as long as you understand it and take appropriate measures there’s no need to panic. I raised it way back when the first discussions of venting were taking place here. A refresher - note especially Factor 3 in the section “When Things Go Wrong”.
Combustion Gases in Your Home – Things You Should Know About Combustion Spillage
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Wow, @whitehill, thanks! I was beginning to think I was making a mountain out of an air pressure molehill. I have some reading to do now.
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I would upgrade to a fan like this but I need one that can be mounted outside.
i feel like someone early on mounted an exterior fan with PVC pipe running alongside the house up above the roofline. saying part of why they did it that way was so that it looked like a radon thing, maybe?
Yeah, a radon fan may be my best option, and it was @dwardio.
I just posted a question on amazon about the cloudline fan and weatherproof-ness. I’ll report back.
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Here is the ultmate solution: The Glowforge is located in a well sealed box wih a transparent lid so you can do fire watch. Outside air is cooled and dried (air conditioner) and enters the box & inlets of the 'Forge. Then a powerful external fan exhausts to the outdoors. Shoot, you could even use an inert gas to elimimate all risk of fire. It will not over heat on the hottest summer days.
Not sure if this meets your definition of “outside”, but I mounted one of these on the garage of the home I was living in 22 years ago, and it’s still running strong today:
An enclosure on the inside wall would allow you to duct the draw wherever needed.
In my case, the garage doors were south-facing and the garage was below the master bedroom. The sun would cook the doors (even insulated) and heat up the garage, which then heated the bedroom. I hooked the fan to a thermostat that triggered automatically, like an attic fan. It wasn’t quiet, but certainly quieter than the GF exhaust fan.
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For anyone going the distance, and have a 3D printer: found this.
Edit: didn’t read all I’d found. 6-4”
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Here’s another good write-up on it:
It also addresses a Texas A&M study that very much pertains to the way a lot of these are set up with flex dryer vent hoses:
“ Texas A&M did a study on the effect of flex duct not pulled tight and the results are astounding. In my article on this research, I showed from their results that a 6" duct moving 110 cfm when pulled tight will move only about 70 cfm with 4% linear (longitudinal) compression and about 40 cfm or less at 15% compression.”
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Yup. Flexible duct should be a last resort, not the first choice.
Ok, I’m seriously planning on getting an external fan and I want to pull out the internal fan. First is there any reason I wouldn’t want to do this? It would be easy to reinstall and it would make air flow much better. And second as I was surveying the situation I noticed that there are posts molded right on the base in front of the fan mounting screws. I’m thinking they are to mount the additional cooling parts that a basic does not have. Should they be able to be cut out without consequence? Maybe I wouldn’t even have to cut them out but they look like they would impede the removal of the bottom fan screws.
The posts are for a huge heatsink that the pro has, which makes removing the fan a royal PIA.
You really don’t have to remove them but there’s no harm in doing so on a non-Pro.
As to reasons why not to remove the fan, really there are none if you’re out of warranty. At some point, GF could have the machine check for the presence of the fan and throw an error if not found.
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is it concrete?
if so you could put a plug in there to guide a nice rented hammer drill with a 6" hole cutter.
the plug being a piece of wood with a pilot hold drilled in it. you could conceivably use tapcon screws to mount the guide board.
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Thank you for the info! I was going to tag you because I knew you pulled your fan but I forgot. I’m glad you saw it and chimed in.
I have the Pro w/ the Glowforge air-filter… what should I get to make it less LOUD?
I don’t think my neighbors and landlord would be happy. 
Plus I just bought this filter and no way I’m not going to use it.
Well the reason I’m asking is if you don’t use the filter then you can install the external fan mentioned above (will include amazon link below) and the Glowforge will be MUCH, MUCH quieter inside your home and you really won’t hear it at all outside your house. There will still be some smell outside but that will just depend on how close you are to neighbors.
I recently moved but I was in a guesthouse that was right up to the main house and it wasn’t a problem for my landlords in the main house at all. Obviously YMMW.
(not an affiliate link)
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Additionally, many find the air filter becomes pretty pricey to operate as the replacement filters are $250 each and depending on what you cut can fill up quickly.
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