safety Dust collection DIY- Questions about a proposed system

[Kerri Duncan]

I have looked back at a lot of folks posting about dust collection- Ive read the threads going back to pre-2015... Im looking to build a system for my small shop- and wanted to get some opinions/input before I jumped in from those who have gone before me (you guys)... As there is nothing really solid recently in the forums I figured I would ask for some input.

 

I will be putting this system on a surface grinder as well as my 2x72 using blast gates or a "Y" switch at the input.

 

My decidedly LOW TECH method of controlling ambient dust has been working very well so far but I have a LOT of residual dust landing on everything (neodymium magnets in sandwich baggies hung around the rafters- they get fuzzy QUICK. Easy to clean though- just turn the baggie inside out, remove the magnet, dump the bag then put magnet back in the bag and re-hang)

 

Watched Neils series and loved it- and recently came across Dan Comeau's spark arrestor idea here:  DC KNIVES SPARK ARRESTOR  This solution mechanically mimics industrial solutions for the same issue, and would appear to be very do-able for my level of abilities.

 

So I wanted to get feedback on using a Fan Blowing across me towards the dust inlet, a Water trap at the grinder inlet, then a Spark Arrestor in-line,  and a modified Dust Deputy/ canister filter setup on the end... really trying to aim for cooling the sparks before the canister.

 

I found a setup similar to what I would like to construct- it has a Dust Deputy mounted to a modified Chinese-Freight dust collector. The user modified the system and added a larger diameter impeller (In this blog he purchased a Rikon impeller). The larger impeller upped his CFM and static pressure.  The video of the system is at the bottom of the page, and below that is a "blow by blow" tutorial- Here is the link to the blog-post: GRAYHOUSE STUDIO HF DUST COLLECTOR MOD

 

So- My questions are:

1- Is this overkill? I do not think so as I already use partial face masks and 3M cartridge filters- but need to get the dust under control if I gear up or hope to keep anything clean!

 

2- One way to "boost" the system efficiency is to have a fan blowing on me towards the dust collection port as well- Does this sound crazy? (In lab situations and vapor spaces I have been exposed to the workers are in-line with the airflow to keep a positive pressure vent circuit in place.)

 

Any thoughts are appreciated- Ive been gone far too long from this fellowship. Be safe and well!

 

 

 

[Charles dP]

Hi Kerry. I’m afraid I don’t have any useful input. I just didn’t want you to feel ignored 

[Kerri Duncan]

Understood- Going to be building it anyway- just would have liked to get a few thoughts from the collective. 

 

I just have to keep the shop a bit cleaner than some as it is also a shared space for the wife and my jewelry work (And Ive got a 6 year old I would like to have playing about as well)

 

 

[Charles dP]

Cool. Keep us updated with your progress. We may have some useful ideas yet 

[Simon W]

I can't comment too much on dust collectors, there are definitely people here with a lot more knowledge on what works & doesn't work, but I can share what I did earlier this year. I have a small shop too, and it was annoying having grinding dust settling on everything. So I put together a simple water trap/dust collector connected to my shop vac that is surprisingly effective.

 

 

A 4" to 5" duct adapter connects to 3" aluminum drier flex hose & into the top of a 4gal steel pail with latching lid. The flex hose is attached to a 3" pipe centered on the lid that extends 6-8" into the pail. On the side is another pipe where you plug into your vacuum, I had to resize this to about 2.25" dia to suit the shop vac fittings. You'll notice I cut the end of the pipe at an angle and positioned the angled opening roughly at a tangent to the pail body. I was hoping that would direct the airflow around the pail similar to a cyclonic separator, but the that effect seems to be minimal if it's happening at all. (I threw my phone in the bottom and recorded sucking up some torn paper, the air flow seemed to be pretty random inside).

 

With an inch or so of water in the bottom of the pail, its been catching all of the steel grinding dust before getting to the shop vac. Initially I had included a smaller pail inside that held the water directly under the intake pipe, but this just caused a lot of turbulence on the surface of the water, sucking up a fair bit of moisture into the shop vac canister. It seems to be just as effective filling the bottom of the 4gal pail but without dealing with water in the shop vac.

 

I've not figured out a great mounting method for the mouth of the collector yet, so far I've just been using bar & spring clamps to get it near whatever I'm working on. I don't have a belt grinder yet, but it's been working well enough with an angle grinder, as long as I can direct the spray of sparks mostly into the collector.

 

That inline spark arrestor looks pretty effective though, be interested to see how that works out if you proceed with it.

[Kerri Duncan]

On 7/26/2021 at 3:03 PM, Simon W said:

I can't comment too much on dust collectors, there are definitely people here with a lot more knowledge on what works & doesn't work, but I can share what I did earlier this year. I have a small shop too, and it was annoying having grinding dust settling on everything. So I put together a simple water trap/dust collector connected to my shop vac that is surprisingly effective.

 

That inline spark arrestor looks pretty effective though, be interested to see how that works out if you proceed with it.

 

Thanks Simon- Im in the process of fabri-cobbling a setup right now... I like the water/bucket idea- I'll be using a rectangular "tote" bin- One fellows shop near me who does a LOT of plasma cutting has a similar setup with a "tote bin" style water trap.

 

The big thing for him is deflection/cooling of the particles- he added a stainless steel mesh screen like you find on range hoods and over house stoves into the water. He lost a few feet of CFM and a bit of static pressure- but he hasnt burned out his shop collection system since adding it.

 

Im working with a couple of ideas about the inline arrestor- Dan, (the fellow who wrote the blog post) was kind enough to chat a few emails worth of info- after a year of use the head of the vanes and the central fixtures are not abraded or significantly worn down. 

 

I think one of the success factors to his solution lies in the fact that the surfaces of the vanes are NOT smooth- it "forces" turbulence into the airstream, causing the particles to bounce around more (plus the lower pressure combined with the centrifugal action of the vanes) contribute to a longer air-path for the spark to travel and expend its energy.

 

For ambient dust collection- I think there is a solid calling for a fan-tower.  Ron Calverly on YT has a good build and I already have the blowers - I know its a tall setup- but Im looking at putting a timer switch on it to run after I leave for the night to keep filtration going... I have some sensitive pieces I cant get dirty out in the shop (Some of them being the wife's tools) and an Optical Comparator to keep clean. They already have dust covers- but looking for more substantial long term solutions.

 

Ill keep you posted- build should start after I get the tablesaw cart built to get the wife's tools some much needed storage! Below is the vid for the cabinet.