DC pipe?

[Al Killian]

I was surfing the net the other day and ran across a few sites that said that certain types of metal pipes shoul not be used with certain cyclones or other DC units. For anything drawing over 13" of static pressure you should not use anything under 24 gauge. Is this true? If so, how do you know what your unit is pulling? And what are you useing for metal pipe? I have looked at spiral pipebut, at $3.00 a foot it is a bit pricey. The fitting for this pipe is crazy., $40 for a elbow is out of my price range. My current set up is using the heavy gauge 6" round ducting. This can be had for about $1.50 a foot and the fitting are under 10 bucks a piece.
Al

[Lou Ferrarini]

I use PVC. Cheap, easy to find and works just as good as metal IMHO.

[Jim Becker]

Most of the 2-5 hp cyclone systems will be quite happy with 26 gage or heavier metal duct. 30 gage HVAC duct "could" collapse if you have a nicely sealed duct system. Many folks do use thin-wall PVC and it works just fine. The down side is you're limited to 4" or 6" and that can be quite restrictive if you want to use a stepped duct design...there are many times when 4" is too small and 6" is too big...but 5" is "just right".

If you opt for locally produced spiral pipe (and when locally produced it sometimes can be had for only a little more than snap-lock) you don't have to use the really expensive gored elbows, etc. You can still use 24-26 guage adjustable long radius elbows and standard metal dust collection laterals...you just need to use the connectors where appropriate.

[Al Killian]

Thanks Jim. Aguy that we(wife and I) know is going to try to get me a deal on spiral. I looked a pc but in my area it cost almost as much as the spiral. The snap lock pipe that is in my shop is the 26 gauge pipe. With my HF 2hp DC there has been no issues as of yet with collapsing. At the end of the summer my shop is going to be in a different spot and wanted to find out about this before I wasted time and money getting the wrong pipe.

[Jim Becker]

Al, my entire shop is plumbed for DC with 26 guage snap lock with no issues running a 2hp Commercial Cyclone from Oneida. If I were going to replace it, I'd look for spiral just for the neatness factor, although it also offers a little more strength.