View Single Post
  #10   Report Post  
Posted to rec.woodworking
trs80 trs80 is offline
external usenet poster
 
Posts: 122
Default 4" vs 6" duct for Dust collection?

thanks. The Bill Penz site is what got me started. What are you doing for
blast gates?

"Dave Jackson" wrote in message
ink.net...
I am currently using the setup your suggesting, only with a slightly
tricked out Jet 1100cfm DC. Two zones 30ft or so 4" SD pipe w/4 drops on
each zone. I don't know how much better 6" pipe would be but I do know it
wasn't availiable locally so I used 4" and it is working fine for me. The
first zone runs from separator up to ceiling across to right side of TS and
back down and catches planer, TS, overhead guard and jointer. The second
zone runs from the separator along one wall and catches the router table,
band saw, one fitting for a future sander, and it finally reduces to 2 1/2"
to facilitate shop vac hose/fittings for cleaning the shop. I put blast
gates at all the machines plus a blast gate at the start of each zone so
the DC isn't trying to suck air from the zone not being used. Someday I'm
gonna pick up an anemometer just for kicks... Anyway, I'd suggest just
using duct tape to join the fittings and pipe together. If you decide to
change the configuration someday, it's easy to just cut the tape and pull
it all apart. Also, avoid 90 deg elbows wherever possible, they will tend
to clog. I switched to 45deg fittings to make smooth corners and haven't
had a clog since. I found some reducers in the schedule 40 area that fit
the 4"SD and reduced it to 3"pvc (IIRC) that the flex pipe fit over
perfectly. I'll second looking over Bill Pentz website, information
overload on DC's. --dave

"trs80" wrote in message
...
Would a small shop DC system run ok with the mains at 4" smooth bore PVC
ducting vs 6"? I would have about 30' of main and 4 drops using a 2hp
1600cfm unit and air blocks for the station no used. The DC has a 5"
intake and 12" impeller.

I cannot find locally PVC 6" sewer and drain pipe. I can find galvanized
6" duct at about $1.40/ft and 4" smooth bore S&D PVC pipe at $0.58/ft. I
hate to spend more of the duct then the DC which would happen if I go the
metal pipe route.

I visited all local Home supply brands (HD, Lowes, CW) and all dont carry
over 4" pVC. And I called an irrigation supply and they dont carry the
light duty 6" PVC pipe (i think its schedule 2379 or something like
that). Im guessing that its not a big seller inmy area for some reason to
do with building codes for such things.

So any way, I was wondering how much performance I lose by going the 4"
vs 6" route.

Any thoughts appreciated!