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d_todd_phelp
07-12-2011, 02:43 PM
I am in the planning phases of building a barn. The wood shop will go on the 2nd floor of a gambrel barn. Any danger in putting the DC on the 1st floor so the DC input is lower than the tools? The ducts would run up to the machines instead of down to the machines.

Pluses?
- Noise in another room
- Better CFM because debris is always being pulled down, never up.

Minuses?
- Nearly impossible to see how full dust bin is (could use a spy cam)
- Large heavy objects get sucked up into the DC easier (e.g. battery)

Thoughts?

Thanks, Todd

bababrown
07-12-2011, 03:18 PM
I like the approach. You probably will never produce enough dust to have a significant effect on CFM. The height difference isn't enough to make a significant difference. If you go with the CV-1800 or CV-Max you won't have to worry much about heavy junk getting up into the impeller. It will fall into the bin below. Very many of us either put the cyclone in an attached shed or in a closet to reduce noise. So we all face the problem of potentially over-filling the bin. I do it with my mini when it's right in front of me! McRabbet has many posts herein on his full-bin-sensor which by reports works well. What's going in the lower portion? In particular, will it be easy to empty the bin? Good luck,
bababrown

d_todd_phelp
07-12-2011, 03:48 PM
The lower portion would be things like the wife's convertible for winter storage, the tractor, the boat, ATVs, snowmobiles, lawn mowers, etc. Emptying the bin won't be too bad, but will involve walking outside, or installing a fireman's pole.

P.S. The barn is at our retirement property, so I'd simply be moving my current stuff to a crowded barn to the new barn. I am currently using a shop-vac in my current woodshop, and thought I'd get the Dust Collector now. But it'll be severely hampered by a bad duct design (not going to invest time and money into duct work which will get dismantled in about a year).

I'm leaning toward the 1800.

Jim O'Dell
07-12-2011, 07:01 PM
In my dream shop, I have basement space under the shop, with a walk out. Cyclone would be down there. Ducting from underneath. Still fairly easy to redo ducting if tools change/move. So I see no problem with it. If you were talking about burying the duct in concrete, or otherwise have a hard time getting to it like a traditional crawl space in a pier and beam house, I'd try to talk you out of it. Jim.

McRabbet
07-13-2011, 07:00 PM
Todd,

I can answer both of your questions, because I have my ductwork under my shop and I make an excellent bin full sensor that will tell you in your shop when that pesky bin is filled with chips and sawdust.

In my case, I started with a small 1 HP Penn State bag style dust collector on a wireless remote and connected 4" S&D PVC pipe to a shop-built "wye" equipped with a pair of blast gates on the DC inlet port that I could activate with parachute cord from my shop above to open one or the other duct run. The area under my shop is a dry crawl space with 4' to 9' of headroom. Later, I upgraded to a CV-1800 on a concrete slab and ran 6" S&D pipe with floor penetrations where I need them. Having the unit below reduces the shop noise issue substantially.

Because I have challenging access to my crawl space (I need to go outside and enter from behind my house), I needed to know when the bin was full and created two versions of bin sensors (the first followed the concept used by a NC woodworker colleague Alan Schaffter that had a 7 watt candelabra shining 24/7 through to a dusk-to-dawn photocell mounted on the bin inlet and a relay to control DC shutdown -- do an advanced search using my name and "bin sensor" as a search term and you should find my early threads). You'll also find several instances of that design in the Photo Gallery by members that used the design.

More recently, I set up a more reliable system using a circuit designed by another NC woodworking colleague and I now make a low voltage bin sensor system that used a pair of garage door safety sensors (the type that reverse the door when a kind runs through) and high quality strobe and/or horn alarms to warn the user when the bin is filled. I described them with pictures and a diagram in this thread (http://www.clearvuecyclones.com/Bullentin/showpost.php?p=6718&postcount=3) -- the strobe only unit is $150 plus S&H and the unit with a strobe and horn is $175 + S&H. If you look at this referenced thread, you will see that these sensor system links into the standard ClearVue 240 V contactor to shut the systems down automatically. Several CV forum members have purchased my unit -- here are some comments (http://www.clearvuecyclones.com/Bullentin/showthread.php?t=1272) by two recent members here.

Feel free to contact me for more details.

d_todd_phelp
07-15-2011, 04:45 AM
Thanks for the replies and excellent ideas. So now I know it can be done. Now to make sure I have the dust collector and overhead door hardware not interfere with each other. It'll probably be at least a year before I'm at the point where I'm actually hooking things up. You'll probably here from me again at that point.