New shop

[maurice charitat]

I've decreased my work hours by half and my wife is going nuts. I've convinced her that my setting up a better shop would take care of her problems. I ordered a PM2000 for a cabinet saw and allready have a BS and a few other items (jointer/planer etc). I am also setting up a DC system and have gotten a tremendous amount of info from this board. I decided to go with the Grizzly system. I believe I'll go with metal ducting although I'm still trying to figure out that one (where to get the right pipe/fittings). My question comes down to this. I know that the main concern is air volume not velocity so the bigger the duct the better. The griz has a 7" intake. All of my tools have 4" outlets. Doesn't the 4" outlet restrict flow? Is anyone redoing their outlets or do you seperate the airflow with a hood?
Thanks,
Maurice

[glenn bradley]

You'll get a variety of answers on this one. I'm currently 4" all the way as I have a small roll-around DC. My dad is 6" up to the drop and then drops to 4" at the blastgate. Others cut 6" openeings in all their tools and still more have a mixture.

PVC will save you a ton of money on ducting but some folks (not I) subscribe to the 'static danger' theory. On the other hand I have never heard anyone complain about metal ducting other than the price (its the fittings that get ya, not the pipe).

I'll let those that favor specific components post the links to the providers as they will have actual-use comments that will be more valuable than mine in your case. However, you may want to start here: http://www.mcmaster.com/. Search under 'sheet metal duct'

[Jim Becker]

Welcome to SMC and congrats on your new shop and time to be in it!

Relative to your duct work, you design the duct work as a "system". A typical design would be 7" from the cyclone inlet out to the first major branch, reducing to 6" at that point. Many folks will stay with 6" from there out for the main run and make their drops according to the needs of the machines. I typically do 5" or 6" drops for maximum flexibility, reducing at the tool.

On your question about the tools, 4" ports seem to be the rut that most manufacturers are in for most common tools. Some could benefit from a larger 5" or 6" port and some can even be easily updated to that. But a 5" drop to a tool with a 4" port with the reduction right at the port at least gives a little bit of a venturi effect and better performance than a 4" drop.

Whether PVC is actually less expensive or not depends on where you are and what the supply is for both the pipe and the fittings. PVC is also only available in "even" inch sizes. My preference is metal relative to that last one. If you investigate, you may find a local fabricator that can supply metal spiral for the cost of snap-lock. Other sources include KenCraft, Oneida, Air Handling Systems and Grizzly.

One thing that Griz does carry that I like is a Nordfab-like quick connect system. While I wouldn't use this "universally", I did put it on a couple overhead drops that I use for my router table and drum sander. It really makes life easier for setup and teardown of those stations as I don't leave the drop connected when it's not actually in use.