JT wrote:

I have a need to convert a 4 inch dust collection system to a smaller
1 1/2 inch connector on a belt & disk sanding station. Is the standard
size for 2 1/2 pipe, a inside or outside diameter? If it usually a
outside diameter, what is the usual inside measurements? If I purchase
2 1/2 inch flexible pipe where can I find the correct fittings to mate
the 2 1/2 inch pipe to the 1 1/2 in connector on the sander?

You will most likely have to reduce the 4" in two stages. First a 4" to
2.5" O.D. reducer and then use a "Universal Tool Adapter" which has a
"“stepped” design contains a 1", 1-1/4", 1-1/2" and 2" external diameter
and a 1-1/4", 1-1/2" and 2-1/2" internal diameter connection. It also has
a square flange with mounting holes that can be used with a collection
box." See WoodCraft Product Number 142173:
http://shop.woodcraft.com/Woodcraft/...5983EBB27B7330

--
Jack Novak
Buffalo, NY - USA
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