As I continually change, improve, experiment, with my shop I came across an issue in the making. My dust collector has been moved again. With the jerry-rigged hoses I have stretched across the ceiling, most clear, I see chunks of wood that did not have enough velocity to make it to the collector. Dust is starting to collect on those spots possibly due to high humidity right now.
Here is the question: When, not if, my setup is finally complete with a smooth bore tube or pipe will I encounter the same issues?
The spiral dust collection hoses cause turbulance and reduce efficiency of any dc system. Whatever dc source you have needs to be made as efficient as possible. As your dc collects dust the filter becomes clogged chocking your cfm. Addition of a cyclone makes your dc a 2 stage dc system. The cyclonic separator keeps your filter longer giving you the most efficient system no matter how weak or powerful your dc is.
Keeping your dc hose runs as short as possible also helps. Using two 45 degree elbows instead of a single 90 helps. Internal turbulance reduces the cfm.
Now all that said some times you have to give up efficiency in favor of practically. They do sell clear 4 inch dc smooth hose but it is expensive. A good alternative is using schedule 40 pvc pipe with adapters to your dc hose sizes. 4 inch pvc and 4 inch dc hose are not the same sizes.
There are a bunch of videos on youtube that can help you plan and execute a dc system.
I currently have my system cobbled together until I can get to my ultimate goal of placing the DC in a dog house outside with a cyclone inside. Right now I have a Model A in the way. Yes, I had planned to do smooth bore pipe for my ultimate system. My shop is 30 X 20, unfortunately, I have to place the DC at the furthest point from my machine. +/- 30’, +/- 10’ drops, lead hoses to my machines. Don’t forget the gates, they leak a bit.
Have a Harbor Freight DC with a one micron bag that lowers the efficiency but saves my lungs. Wife hates it when I send the bag through the washing machine.
Wondering if there may be issues with debris collecting in the smooth bore tubing over time as I am seeing with my temporary spiral hose. When I become rich and famous I will increase the CFM’s.
A large piece of debris can get stuck anywhere. Dust can pool in low spots or at transition points. With flat wall pipe there is not as many obstructions to catch or slow down saw dust.
The key to dust collection is not vaccum but cubic feet of air per minute (cfm). The movement of air moves sawdust. If you had a 1 inch pipe with a good vaccum source and a 4 inch pipe with same vaccum source the 4 inch pipe would gather more sawdust because there is more cfm moving air over the 1 inch pipe. So my earlier comments making whatever you have more efficient is more important than which system you have. Leaks rob your system of efficiency. Seal up leaks with alum duct tape. Make transtions as gentle as possible. Make as few reductions in size as possible and if you have to reduce size make that transtion as far down the line as possible.
You can chase your tail for perfection but at some point you get diminishing returns for time and money spent.