Replies

1. 
   SARGEgrinder47 | Jun 27, 2007 05:24pm | #1

   Morning Geir..

   "So either it is not doing in practice what it should do in theory. OR I am doing some other thing wrong. Too long hose? Sharp bends? Is clogging of the filter sack above an issue"?... Geir

   Not enough details but.......... probably all the above and who's theory was it that states 750 CFM is enough to handle a 12" jointer-planer? If the machine is rated 750 CFM, you won't get 750 CFM if you add a hose, turn or reduction. It's going to drop with every foot of hose and turn added.

   Also.. if you take the face of the propeller housing off, you may find a screen or plate that is there to trap large chips before they make it to the motor. That will reduce the CFM also as it partially blocks the opening and the CFM was probably not rated with it in place.

   So... after having the same problem when adding a 20" planer.. 8" jointer I got a cyclone and eliminated the problem altogether as the reality (not theory) is I can't expect a Chevy S-10 to pull a load more suited for a Peter-bilt tractor.

   Got to get ready for work... I'm sure others will add their opinions!

   Regards...

   Sarge.. jt

2. 
   JohnWW | Jun 27, 2007 07:01pm | #2

   Clogging in the hose is usually caused by something in the hose that is snagging shavings, or a sharp change in diameter or direction that again traps shavings.

   As to the size of your system, it is very unlikely that a 3/4 HP motor is delivering anywhere near 750 CFM at the end of the hose, these things are often rated at by the makers with no hose and often no filter attached to the blower.  Even the smallest of the portable dust collectors have a 1 1/2 HP motor.

   John White, Shop Manger, Fine Woodworking Magazine