DC Duct Length Below Cyclone

I'm setting up a two stage system and in my work area, it's logical for the impeller and cyclone to be very high up on my wall, but I would still like easy access to my sawdust barrel that sits under the cyclone. Does the length of the ducting that runs from bottom of the cyclone to the barrel matter? I know that everywhere else in my system every foot length of duct matters, but in this case, it is literally just a gravity drop of the dust being dropped from the cyclone? Would a 4-6 ft pipe there cause a problem with the airflow of the other components? Doesn't seem like it would but when it comes to airflow dynamics, I've been very wrong before...

Thanks.

You must have high ceilings. My ceiling is 9' and I have maybe a foot of flex between the cyclone and the drum. If you use a clear pipe it will give you a good view of your barrel filling up if it is accessible from your shop. I hang a trouble light behind my hose so if it gets full when I am planing lumber I can see it.

Mine is set up like that, as long as it's sealed it's good.

It can be as long as you need it to be with no issue...with the proviso that's already been mentioned: It must be absolutely sealed. Even a tiny pin-hole can cause havoc.

Thanks for the information on sealing. I knew that sealing was important but I didn't realize that it was quite THAT important. I'll be sure to take precautions.

Just to add to your confidence, I helped a local friend install her Oneida cyclone in the upstairs of her shop building. The barrel is on the floor in the actual shop. So the duct from the cone to the barrel is 8+ feet long. (High ceiling in the shop)

This really intrigues me. My 3hp cyclone is upstairs in my shop, but the woodwork gets done downstairs. I have a short type cyclone (Jet) hooked up for the exhaust to go through a baffle (for outside noise suppression) and then vented outside. It’s been going strong for about a year, but just recently I noticed a loss of suction so I investigated. Some larger shavings had migrated from the cyclone to the exhaust baffle and were constricting airflow to the outside. Once I cleaned up the baffle everything went back to normal, but I can’t help thinking that the squatted profile of my DC contributed to the cyclone not capturing enough of the bigger shavings. If I drop the collection barrel to downstairs by extending the collector “downspout” through the floor would it actually improve the efficiency of large chip collection?

Daniel, your blow-by could also have been caused by a leak between the cone and the bin...even the tiniest leak can cause that. Relative to your question, putting the bin in the shop below isn't unusual...I helped a local friend install her Oneida system in the upstairs of here shop a few years ago and the barrel is downstairs in the shop for easy handling. The distance really doesn't matter...it just needs to be 100% sealed with zero leakage.