Flexible dryer vent for casting vent?

[Patrick L]

I am in the process of building a new casting area. I have an old range hood I want to vent outside, but I don't want the setup to be permanent. I would like to use flexible dryer vent to connect the exhaust fan to a board I cut to fit an open window just above and behind the setup.

Is this stuff adequate, or do I need tin ductwork?

[44woody]

Patrick L sounds like you have a good plain there it will work fine:castmine:44Woody

[shooter93]

Use the flexible Aluminium duct.

[MT Gianni]

I would use 4" tin duct and suspend the fan and hood from 4 chains. Take it all down when you are done. It will last 10-20 times longer and you shouldn't need 6'. Gianni

[snowman]

Use the rigid 4" not the flexible stuff. It flows SOOO much better. Once I started using that on the dryer, I think we cut about 5 minutes of drying time on a load of towels.

[felix]

If you are talking flow capability, rectangle piping offers less air resistance than something round. Might or might not be a practical fit where you need it. The only reason for less resistance being better is that you can get by with a lower powered fan. And, that's better because of wind and motor noise, and will draw less air out of the room keeping your heating/cooling requirements down. On the otherhand, we might be talking overkill unless you are going to be casting often. ... felix

[Dale53]

I have purchased an inline blower for 4" dryer vent pipe. It will be permanent in my case but that is certainly not a requirement. I should have it installed in a couple of weeks after I get back to Ohio from Utah.

I have a friend who has long used a 4" flex pipe to fasten to the top of his lead pots (comes in at right angles to the top and is clamped to the top of the pot with one of the bolt heads). He has no problem fastening it and removing it in a minute or so. It works VERY well. I presently have a LARGE vent hood that is actually TOO efficient. It pulls all of the A/C or Heat from the building. My new set up is intended to correct that.

Dale53

[Steelshooter]

Patrick L
Hard pipe is the way to do it, you can get everything you need at home depot or any decent hardware store. Go with the round pipe it is a heck of lot cheaper and more efficent than the rectangle.

[felix]

More efficient in terms of flow, by far, in terms of volume of air capability for the same space taken up. However, the round pipe offers a large increase in air resistance to the flow because the air likes to hug the walls and therefore requires offsetting fan power. GE did these comparisons back in the 50's when air conditioners were becoming prevalent and that is why the rectangles became the mainstay in quality installations. ... felix

[Steelshooter]

Felix
No pi$$ing contest but the corners of the duct cause turbulence and more resistance than round and is cheaper and more available than rectangle.

[Dale53]

Frankly, who cares:mrgreen: which is more efficient. Both will work just fine. The round is a lot more available and is relatively inexpensive. Not intending to be argumentative, as we are all friends here, but my friend has used his set up with several automatic casters (a pipe to each machine) and they work just fine.

My problem is drilling through the walls in my utility barn without cutting into a (no longer remembered) power line. If any of you bump into me and BOTH of my hairs are standing up on my head, you'll know that I didn't miss the wiring...

Dale53

[montana_charlie]

Frankly, who cares:mrgreen: which is more efficient.
I do!

I was waiting to find out the truth before going in search of rectangular garden hose...for those applications where I need more pressure, but less volume.

Since that debate has been squelched, I guess I'll just sit back and watch my nozzle dribble... or drizzle... or drivel...?

[Lee]

Just watch out for that hexagonal, polygonal rifled garden hose. I hear it causes quite a lot of ka-splashes...................................Lee:win k:

[felix]

Yeah, nobody should care about such a short run anyway, Dale! SS, which would cause more turbulence and more resistance: 1. Shooting a 30-30 round in a 30-30. 2. Shooting a 30-30 round in a 32WS. ... felix

[Trez Hensley]

I personally think the octagon shaped pipe is the coolist. It only cost about $25 a foot to have made at the local metal fab place. It's SWEET!!

[standles]

When I was casting in an Apt. I used a bathroom exhaust fan hooked to the pvc dryer vent attached to a board in the window as you described. Worked great.

Steven