# Another Newb Question



## ghostrider (Oct 31, 2012)

Here's another question (or maybe a seires of them).

I hear so many good things about the Ridgid wet/dry vacs and how good their suction is. I called Ridgid to ask what their static/sealed pressure is and was told that it had 50-inches of water lift (It may have been 47 because I checked on the 14gal also) with 203 CFM for the 16 gal, WD 1851. The Lowes Shop-Vac claims 210 CFM with 60-inches of sealed pressure. 

My question/s is, "Has anyone here figured out a way to determine the difference in performance without a side-by-side comparison? 

Also, the filters on the Ridgid look like they have more surface area. Isn't that going to affect air flow?

The Ridgid costs about $40 more and comes with noise suppression. The Shop-Vac claims more sealed/static pressure, and air flow. It sounds like the Ridgid machine has a better reputation for both reliability and customer service, but if the Shop-Vac will such more chips-n'-dust, then I'm willing to go with it. 

Thanks in advance for the help. People around here have been very helpful in guiding me through these unfamiliar waters. I'm trying to educate myself, and the help is much appreciated.


----------



## Yeorwned (Jan 9, 2010)

There isn't near as much to analyze on shop vacuums as there is in a complete shop dust collector/collection system. Any standard issue shop vacuum like the Ridgid or Shop-Vac are very loud, regardless of the "noise suppression" attachment, which does very little. I wouldn't tell you to spend any more than $60 on a standard shop vacuum for general use. Otherwise, save your money up and buy a higher end woodworking vacuum (often called dust extractors) like a Fein, Festool, or Dewalt. Ridgid does make a higher end model that they call a dust extractor but I don't know what models you're looking at.

Based on my own experience, there really is a huge difference between a standard Ridgid and a Fein for the purpose of dust collection in woodworking. While the Fein might seem grossly overpriced, the value is definitely there from my experience. Woodworking becomes significantly more pleasant with the Fein. Everything from not having to monkey around with an automatic switch attachment, antistatic hose which is more flexible, whisper quiet operation, mobility, and never ending filter surface area pays for itself faster than you can imagine. The Festool reviewed as performing the same but cost more.

I don't know if that helps at all but good luck with your search! Never under-estimate the value of dust collection.


----------



## ghostrider (Oct 31, 2012)

That's one thing I still don't understand when it comes to extractors v shop vacs.

The shop vac can almost double the cfm, and the hose size is smaller on every extractor I've looked at. I know that the extractors have the bells and whistles, but it seems like the vac would perform better for dust removal. 

Is it just the "bells and whistles" that give the extractor an edge, or am I missing something?


----------



## Dave Paine (May 30, 2012)

ghostrider said:


> That's one thing I still don't understand when it comes to extractors v shop vacs.
> 
> The shop vac can almost double the cfm, and the hose size is smaller on every extractor I've looked at. I know that the extractors have the bells and whistles, but it seems like the vac would perform better for dust removal.
> 
> Is it just the "bells and whistles" that give the extractor an edge, or am I missing something?


There is a fundamental design difference between the Fein/Festool dust extractors and "shop vacs".

Fein and Festool use two motors. One for the blower for the vac and a separate one to cool the first motor. These motors are lower rpm, which means low noise. I have the previous model of this Fein.

http://www.cpofein.com/fein-9-20-26...actor/fenn9-20-26,default,pd.html&carousel=18

I have a friend with a Festool. The Festool makes a bit less noise than the Fein, but the Fein is quiet compared to a "shop vac".

"Shop vacs" use a single so called universal motor to power the blower and cool the motor. The universal motors are high rpm which generates a lot of noise.

Fein and Festool are famous for having high static pressure. High 90's.

The "shop vacs" will typically have less static pressure, but may have more rated CFM's.

It is very difficult to find the "head pressure" curves for either dust extractors or "shop vacs". This would be so useful to compare real world predicted performance.

A rating of *** CFM is typically made at the tool inlet without the hose. Adding the hose instantly adds pressure drop.

Depending on the machine design, one machine may lose more CFM just by attaching the hose than the other.

If you attach the hose to a fitting or a tool there is more pressure drop, and so the CFM's will again drop. We just do not know by how much.

My Fein is likely rated at "only" 126 CFM, but I expect in a real world condition my Fein will pull more dust than most "shop vacs".

I just love the low noise of the Fein. My wife used to complain at the noise of the previous Rigid when she needed to use it to clean out her car. She does not complain about using the Fein.

My Rigid is over 10 years old and finally the motor bearings died. I still used this in another room for a number of years. It was not as effective at real world dust removal as the Fein, and it was really loud, even with the noise muffler, which did reduce the noise, but only slightly. It still screamed like the proverbial banshee.


----------

