Dust collection -- question from newbie

[M Smith]

Greetings all, I have what to me is a not an easy question to get an answer to, but I'm guessing someone here can help me out :).

When reading descriptions of fittings and hoses, they are listed in 4" diameter, 3" diameter, 2" diameter, etc. Do those diameters refer to inside or outside diameter?

I have a planer that has a dust port, with an inside diameter of about 1 7/8" and an outside diameter of 2 1/16" (roughly). I desperately need to hook it up so as to minimize the junk in my garage, but can't for the life of me find hose and fitting descriptions that match my needs.

Help (please)!

Thanks!

[Frank Hagan]

When reading descriptions of fittings and hoses, they are listed in 4" diameter, 3" diameter, 2" diameter, etc. Do those diameters refer to inside or outside diameter?

I have a planer that has a dust port, with an inside diameter of about 1 7/8" and an outside diameter of 2 1/16" (roughly). I desperately need to hook it up so as to minimize the junk in my garage, but can't for the life of me find hose and fitting descriptions that match my needs.



Pipe sizes are "nominal", meaning they don't really measure up to the exact measurement. Most rigid plastic pipe I'm familiar with uses the outside measurement; that's to accommodate the same fittings for different thicknesses of pipe.

The chart at http://www.cutpipe.com/howpplp.htm shows 2" pipe to have 2.375" (2 3/8") outside diameter and 1 1/2" to have a 1.9" outside diameter. Your 1.9" ID sounds close to 1 7/8" to me (7/8" is .875 of an inch, if I remember correctly).

[M Smith]

Pipe sizes are "nominal", meaning they don't really measure up to the exact measurement. Most rigid plastic pipe I'm familiar with uses the outside measurement; that's to accommodate the same fittings for different thicknesses of pipe.

The chart at http://www.cutpipe.com/howpplp.htm shows 2" pipe to have 2.375" (2 3/8") outside diameter and 1 1/2" to have a 1.9" outside diameter. Your 1.9" ID sounds close to 1 7/8" to me (7/8" is .875 of an inch, if I remember correctly).

Frank,

Thanks for the link to that chart and attempting to clarify this for me. So, if the dust port on my planer has an OD of 2" (meaning 2 3/8" or close to that), then I need a hose of 2.5" OD (meaning an ID of 2.3"-ish)?

Mark

[Mike Lipke]

Go to a big hardware store or a plumbing supply house and tell them you want a Mission (there are other brands) Coupling.
Plumbers use them to connect drain pipes of different sizes. They are heavy rubber, with stainless steel bands that tighten over the pipe. They come in different sizes, some even are meant to mate pipes like 4" to 2".