Larry said it.You are not concerned about plugging the 4 inch duct.You are concerned that the air will flow freely so it can carry your stuffespecially the very fine dust.My system has 6 inch every place except the drops from the 6 inch to the machines.I even have 6 inch drops a couple places.
The rikon blowers to modify a harbor freight duct collector are back in stock.I completed my modification last week.Very easy to do.Remember the blower attachment bolt is left hand thread.A pulley puller will be needed to remove the old blower.
Modified harbor freight dust collector.Facebook.Twitter.Pinterest.Simply lift the assembly up about a half inch and slide the pine spacer in to support it.One on each side.But i do find the static does charge up on the outside of the flex duct and perhaps the dust bin if its plastic, which makes for a pia with all the clingy.
Beautiful work on that.I used the same harbor freight collector for my custom collection project 6 months ago.For my blast gates, ducts, collector, highland filter, separator, etc, my total cost was about 850, not bad for a complete system.
A spark trap can be installed vertically or horizontally.For proper functioning of the spark trap, the length of duct between the spark source and the spark trap should be at least one duct diameter, and between the spark trap and the dust collector should be at least ten times the duct.
From the collector and run it in free air on your workbench a realistic system rating is more complex.Velocity if a fixed cfm of air is forced from a large duct into a smaller diameter pipe it will move faster, and viceversa.Sometimes even a large volume of slowmoving air may not suspend dust moving through a long duct.
In the geek pub dust collection system, we wrapped the pvc pipe with braided copper ground wire kit.At approximately every 48 inches the wire was terminated to a grounding lug via a 34 inch screw that penetrated to the interior of the pvc pipe.
I finally got around to installing a dust collection system in the shop, or i should say i finally took my health more seriously.Last year i started having breathing difficulties after working all day.It became apparent i needed to step up and spend the money now, instead of on medical bills later.Now that it is installed, i cant believe i waited so long, it is an absolute night and day.