Reducer Connections For Dust Vacuum System

[Wiley's Woodworks]

I'm trying to fit machinery that used to be in a 2 car garage into a 1 car garage with a side room. Floor space is at a real premium. It's looking like the old shop vacuum dust collection system--a large 2 stage Jet standing vacuum with 4" hoses running all around the shop and flow gates on 6 machines has to be sacrificed. I want to replace it with a couple of high HP shop vacs on wheels, and just roll them around to whatever tool I'm using. First problem I'm running into is finding connectors that will fit onto the 4" outlet ports on the tools and reduce down to the 2 1/2" hoses on the mobile vacuums.

Two questions: Will vacuums with 6- 6.5 HP motors and 2 1/2" hoses that are relatively short (7') pull the sawdust and wood chips out of routers, planers, jointers, table saws, roller sanders, etc., and where can I locate reliable connector/reducers that will stay permanently mounted on each tool?

 

[Alan in Little Washington]

You'll get varying opinions on that. But first some basics- 6 - 6.5 hp on a shopvac is a scam no such thing- the manufacturers play fast and lose with how they compute hp. Secondly- a shopvac pulls suction, typically 80 to 120 inches of water but not much volume. A true dust collector will only pull about 8 inches of water suction but will move several hundred CFM. If you only want to pick up chips and some dust from inside a small machine, a shopvac will do that mostly, but if you are trying to collect chips and dust and prevent fine (dangerous) dust that escapes from most WW machines, you need the CFM that only a dust collector with material handling blower can generate.

So to answer your question, if you are mainly trying to capture and pick up chips and some dust from a router or ROS through a small hose then a shopvac is fine. If you are trying to collect chips and the fine dust that can get into the air that you breathe (and is a danger to your lungs) you need a true dust collector. Most shopvacs can not handle the amount of dust and chips generated by a planer, certainly not a jointer, drum sander, or table saw due to cabinet design and/or exposed cutters.

All the usual suspects (Klingspor, Rockler, Woodcraft, etc.) sell adapters. You can also use a variety of Fernco neoprene plumbing fittings. Remember the hose and fittings will be under suction, so will be inclined to stay put if just friction fit.

 

[patlaw]

Klingspor has a lot of fittings, as does Woodcraft. Be aware that the fittings are not as standard as you would think. One company's 2-1/2" adapter doesn't fit the same as another company's. I have a tub full of fittings that don't fit. In any case, I did find an adapter to connect my Ridgid shop vac to the 2-1/2" port on my router table.

 

[JimD]

I used to have a small 1 hp Delta DC but it was too small to be terribly effective and my shop is only 14x24 so I am using a shop vac, at least for now. I have a 10amp Rigid pulling through a dust deputy. I use a 20 foot 2.5 inch hose on my table saw and router table and a Bosch 35mm hose for sanders and other small tools. My table saw is a Ryobi BT3100 which has a dust chute that has a 2.5 inch connection - so I do not need an adapter. The shop vac works about as well on my small table saw as my small DC did. But neither will collect the chips well from my 10 inch planner or my 8 5/8 jointer. They generate too many too quickly. It works well on the small tools.

If you find a plastic plumbing fitting close to the size you want, it is fairly easy to modify it with a heat gun. HVAC metal fittings also sometimes work.

My strategy for the planner and jointer is just to sweep up after using them. I also open the garage door at one end of the shop. Depending on the length of the boards, sometimes I have to do that anyway.

I may get a SawStop and will have to think about a DC for it. I will try the shop vac first, however. I don't think table saws generate too much debris too quickly for a shop vac, unless possibly with a dado blade, but it's a question of how well ducted the SawStop is. The shop vac may work.

The largest shop vacs draw 12 amps. So mine is not quite the biggest. But it is the biggest I could find with a small debris tank. With the cyclone, you don't need much debris storage on the shop vac. I was trying to minimize the space the shop vac takes up. But 12 amp motors do not generate more than about 1hp. Universal motors, like shop vacs use, are also not terribly efficient. So a real hp rating would be more like 3/4. I think mine is labeled 6hp. But that is nonsense. It is calculated using the stall torque and the running rpm. The motor can never generate the stall torque at the running rpm.