Duct work and various sundries...

Jeff Horton

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I have decided to build a dust collection system in my shop. Going to buy a blower, mount it outside and duct everything outside. One of the great things about living in the country, I can do this.

It's going to be a long term project because of the cost. So looking for sources and information now.

I need to start planning the duct system. I lean toward PVC because it's easy to work with. I think I read that metal was now cheaper than PVC? Anyone know for sure?

Any sources for things such as blast gates and the machine adapters I will need?

I remember somewhere I saw a blast gate someone built themselves but it was at least a year ago. No idea where it was.

Any info or webs sites you care to pass along would be welcome.
 
You'd have to check locally but maybe the metal is cheaper, dunno...?
You can make good blast gates yourself, I've done it several times, the biggest thing is to NOT make them too tight! you want the full slide through type, they work the best. I hope you are going for 6" ducting.

Here is how I make >> Blast Gates <<
 
I have decided to build a dust collection system in my shop. Going to buy a blower, mount it outside and duct everything outside. One of the great things about living in the country, I can do this.

It's going to be a long term project because of the cost. So looking for sources and information now.

I need to start planning the duct system. I lean toward PVC because it's easy to work with. I think I read that metal was now cheaper than PVC? Anyone know for sure?

Any sources for things such as blast gates and the machine adapters I will need? I purchased all of my PVC at a local place that sold to landscaping people. I used SandD Schedule 35. I am quite sure a lighter weight product would have worked as well and been less expensive.

I remember somewhere I saw a blast gate someone built themselves but it was at least a year ago. No idea where it was.
It was here on FWW. Do a search, you should find it.

Any info or webs sites you care to pass along would be welcome.
BillPenz.com is the guru of dust collection. There is a tremendous amount of good information. However, the part about computing pipe size was too complicated for my antique brain.

Using the different size pipes that Penz math will lead you to has one great big problem. You WILL modify your system several times as you change equipment, what you make, and a whole bunch of other reasons. Different size pipes will up your cost when you change things. It will make changes much more difficult (like: I need a 3ft section of 4inch pipe; all I have out back is 5inch---I need a 6inch 45 degree el; all I have is 4 inch).

I really searched Dust Collection (20 or 30 hours comparing systems, air speed, static pressure, etc. would not surprise me. I purchased several books on the subject. I searched the web, etc.). It was my No. One priority when I set up shop. After all of that research, what I did was run all 6 in pipe with 4 inch drops to each machine. The reason I did that was that I found quite a few people who had done that and were very happy. I am very happy that I did also.

My original drops were 4 inch flex. I did that for two reasons: 1) It was cheaper than solid pipe and 2) It was faster than plumbing solid pipe. By the way, I am a type "A" personality.

I have used PVC from the beginning. I would not change to metal if it was free. I can trim PVC with ww tools, do it quickly and easily. I cannot do any of those three things with metal. At least when I did it PVC was much less expensive.

I did take to heart, make it easy for the air to move. A vacuum cleaner (read dust collector) does not create a vacuum to pick up the dust. It moves air which carries the dust. Don't do 90 degree turns---Use two 45 degree els with a coupler between to make a much more gradual turn. The finished product should have as little flex hose as possible. We don't live in a square world...Don't be afraid to go 45 degrees if it makes a shorter run (horizontally or vertically).

My DC is a 2 HP PennState unit with 1 micron bags. You get to blow outside so your unit will be more efficient and a lot cheaper without the 1 micron bags to restrict air flow and suck money out of your wallet. Any time I rearrange my ducts I am amazed at how clean they are inside. Everything that goes in makes it all of the way to the collection bag. I have made several threads and posts on FWW about DC. Look up my name on the PM tab and see all of my threads and posts. The wording should clue you to find the DC writings and pictures. You can also do a search on Dust Collection and/or DC.

If you have any questions PM me (Jim C Bradley).

ps. I did not like the plastic blast gates sold by Rockler, WoodCraft and similar. They were quite stiff to open and close. They were a bigger pain than the metal and the amount of money saved was not worth it.

When you get into it I can give you some info on stuff you can buy from the Big Box Hardware's plumbing departments.

Enjoy,

JimB

FOR YOUR HEALTH'S SAKE, GET THE DUST COLLECTION SYSTEM IN AND FUNCTIONING!!!! You cannot do ww (or anything else) if you are dead or have congested lungs.
 
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One of the best places I found to buy pipe and fittings was www.blastgateco.com . There was another company that had good prices. If you can find my dc thread, im sure its in there.

You need some type of business address with a loading dock to get the cheapest freight from them though. I had mine delivered to my work. I think it was 100 shipping to a loading dock, 200 to residential. Might be able to pick it up at a terminal and save the money too.
 
Oh, when I looked, I think 4" sdr was cheaper than metal. 6" was more once you included fittings. I did not price commercial PVC suppliers though, that was just what prices i could find on the web.
 
When I started setting up my new shop, I looked around then decided to go with Oneida to help with my layout. I asked about changes and they checked the engineering and told me I was good to go. They supplied me with some great drawings and BOMs.

As to material, I know many people have used PVC successfully and it's easy to use. I received shocks from 4" flex hose with metal supports in it. I wasn't concerned about explosion using PVC but I decided on metal duct due to the shock hazard.

I spread out my costs somewhat by setting up the 3hp cyclone and using flex while I built my shop. As I firmed up locations for tools, I added drops using a combination of sizes of duct. The DC has an 8" input, so I started with a 7-7-8 wye to have mains going each direction around my space. I go to 6" before each of the first drops and reduce to five inch as I go around the room, then to 4" at machines. I know there is a faction that insists you should take 6" all the way to every machine, but I have had no problem getting great collection with my system.
 
I hope you are going for 6" ducting.

Absolutely! I have done some homework and not having to deal with filters I obviously have the potential for really good air speed. The downside is I will probably have to make at least (2) 90 degree turns to get across the shop and outside to the blower. Probably have at least one more to get to all the machines, but I have not gotten that far yet.
 
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Absolutely! I have done some homework and not having to deal with filters I obviously have the potential for really good air speed. The downside is I will probably have to make at least (2) 90 degree turns to get across the shop and outside to the blower. Probably have at least more one to get to all the machines, but I have not gotten that far yet.

Just make your 90 degree turns using two 45 degree els with a 6 inch long piece of pipe coupling them (The 6 in pipe coupler will make the two 45s touch each other). This makes a very "rounded" 90 degree turn; the air gets around the turn with much less turbulence and resistance. The more freedom the air has to move, the less horsepower you need to accomplish the job.

My pipes are so clean that you "could eat off of them." That is probably true. You cannot wipe up any dust in them except in the little groove where pipe meets fitting. I don't know about bacteria though.

Enjoy,

JimB
 
I forgot to mention blast gates. You said you would probably build some and I had thought the same way. After researching several options, I went with Lee Valley gates. It's a great design and saved me a ton of time by not building my own.

The advice about using 2-45* ells is good. Another option (which I chose) is sweeps; they accomplish the same thing in one piece.
 
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