DC Drops in Middle of Shop

DC Drops in Middle of Shop · 07-03-2009, 02:57 PM

I am planning a DC system for my shop. I know you are not suppose to use 90 deg angles because of air resistance, but I can't picture how to make 45 degree Ys work for drop downs to tools in the middle of the shop. I have quite a few tools which will be away from the walls and to have diagonal pipes would take up a lot of air space and get in the way, wouldn't they? I also think they might not be as stable as a 90 degree drop because of the short length of flexible hose to the tool. Does anyone have any pictures of middle of the shop drops that do not use 90 degree fittings?

Thanks,

gator · 07-03-2009, 04:12 PM

Susan -

Instead of a 90°, use two 45° angles. This gives you a wider sweep around the turn and is almost twice as good as a 90° for air flow.

Edit - Add On: After going back and looking at your shop pictures, it appears that you have a crawl space beneath your floor, as do I. I ran some DC piping through the floor, across the span and up through the floor to the DC. This eliminated flex duct laying on the floor and down(up) spouts by the machines.

George

BKind2Anmls · 07-03-2009, 04:18 PM

I think I've got it. A 45 degree Y off of the main line and then go immediately to a 45 degree elbow so it's almost a drop straight down, right? Although I might need a short piece in between the two to tie them together.

Thanks

gator · 07-03-2009, 04:29 PM

That and any 90° turn you have to make, even to turn a corner, use two 45°'s.

George

Travis Porter · 07-03-2009, 05:51 PM

Sharp 90's are a no-no, but there is nothing wrong with what is called a "sweep" 90. I have two or 3 of them in my shop spread out for the machinery in the middle of the floor.

One thing with having a drop that isn't on a wall is supporting the pipe. I strongly suggesting fastening the pipe to the machine where you can, otherwise, it gets a bit "flimsy".

McRabbet · 07-03-2009, 07:02 PM

Susan, see my post in your Shop thread. Here's a link to the ClearVue site with a few shop layout examples. Use dual 45's at the drops down from the branches.

You may also want to check out their current prices -- Full cyclone "combination" units are on sale until July 31st (cyclone, filters, blast gates relays and remote).

BKind2Anmls · 07-03-2009, 11:39 PM

I guess I'll have a better handle on how things will work once I start running the duct and hookups. I imagine that creating all of the hookups to the various machines will take a long time. From what I've read, it's also recommended to make your own 6" blast gates.

Looks like a great deal on the cyclones. However, I just don't have the money right now. I will be scrambling to get the duct work.

Thanks all

Bas · 07-04-2009, 11:50 PM

You can make your own, lots of posts available on how to do that. That really pays off when you need lots of gates, build them assembly-line style. Or, you can buy them for about $15 -> http://www.blastgateco.com/Cast-Alum...last-Gates.htm (definitely make or buy self-cleaning gates, much much easier than having to disassemble them every year to clean them out).

As for combining 45s to make a ninety - this is what I did in my previous shop. This is with 4" PVC, but it works the same for 6". Basically, it's two 45s connected via a very short piece of pipe. The duct tape is overkill though, friction fit and maybe a little caulk would have been sufficient.

BKind2Anmls · 07-05-2009, 02:05 PM

Thanks for the picture. Should I cut a 6" hole in my dust collector since it currently has 4" ports?

McRabbet · 07-05-2009, 04:38 PM

I'm not sure what model Delta DC you have -- looking at the Model 50-761 (a current 2 HP model), the 4" ports are in a 3-way fitting on the blower inlet and I'd suspect that it would be removable. Delta touts it as a 2100 CFM system, which undoubtedly is a free air reading at best; a 4" duct cannot support much more than 400 CFM. A 6" duct has more than double the cross sectional area of 4" and can thus move a higher volume of air (they easily can carry 800-900 CFM). If that is the model Delta that you have, your biggest challenge after making an adapter is that the entry side oft the blower is from underneath so ductwork up high immediately would require a 180* turn and then another 90* to any horizontal run -- all very costly static pressure impacts on dust collection capacity. Unless you can find a way to mount the DC unit above the duct runs...

But there may be another way to solve your challenge. For about $190 plus shipping, you could buy a 6" version of one of these cyclones and mount your Delta unit above it with a short 6" connecting duct (eliminate the Delta rollaround stand and mount the main blower unit high). Connect the inlet to your main duct run and set up a collection bin below the cyclone as shown on their website. Your Delta unit bags will catch and filter anything that passes the cyclone. Your other choice might be to build your own cyclone like this one or one following Bill Pentz's plans (you can buy a blower and motor from ClearVue if you wanted).

BKind2Anmls · 07-05-2009, 09:18 PM

A friend of mine has a 5HP motor he use to use to blow sawdust out of his old shop. He said I could have it if I wanted to build my own unit. Although I can design wooden projects I'm not good with motors and metal so I've not been inclined to try building one myself. I did notice on one of your links that the guy said he took the plans to a metal shop and had them fabricate the cyclone for him. Maybe I should reconsider and give it a try. But then I've got a barely used Delta DC system. My husband is patient with my hobby, but that might be a little much for him.

I just know I'm tired of spending two hours cleaning for every two hours working in the shop so I want to create a good system.