Soil pipe dust extraction branch?

[dvddvd]

I'm thinking of putting a 110mm soil pipe down the middle of my small workshop ceiling with branches off to each piece of machinery.
I've bought blast gates for each point but undecided which brach connectors to buy, a lot of people say don't buy 90 degrees...

Seems I have a choice of

or the 135 degree ones

 

[dvddvd]

 

[dvddvd]

If I use the 135 degree ones I would still need a 45 degree connector also to get it to run at 90 degrees to my wall...are the top ones unsuitable for dust extraction?

 

[Jacob]

I've always used just one flexible pipe and connected it to the machine I'm using. Saves a lot of fiddling about - you'd have to close off all the unused branches for a start and you have all that extra unused pipe-work cluttering up the workshop.

 

[dvddvd]

Hi it will be fixed to the ceiling so out of the way. At the moment I connect one extractor by flexiable hose to the machine I'm using but 90 percent of the time if its a 10 min job I can not be bothered. I just wanted it so a flick of a switch I have extraction. Plus I'll have a hoover hose at the end of the soil pipe so that way I can get rid of all the Henry hoovers I keep tripping over too.

The blast gates are simple, just keep them closed until you want to use a machine and open it then

 

[Housey210]

static is an issue when using plastic pvc for wood waste, which could cause fine dust to explode. Tips on how to abate on youtube. I have only ever used the spiral metal ducting.

 

[L M Joinery]

I have a spare in the workshop I think, an Axminster one you are welcome to if any use to you?

 

[Housey210]

HSE information sheet

Safe collection of wood waste:
Prevention of fire and explosion

Ductwork
Make ductwork as short as possible with a minimum
number of bends. The design should specify a
minimum transport (or conveying) velocity3 of
20 m/s to minimise dust deposits. Use only conductive
materials for ductwork so that any static electricity
generated can be discharged to earth.

 

[ChaiLatte]

If I use the 135 degree ones I would still need a 45 degree connector also to get it to run at 90 degrees to my wall...

Yes you would.

There are also 15 degree, 30 degree and 0-90 degree adjustable angle bends available (some only in underground specification) if there are any tricky bits.

In general, the brown 110mm pipe and fittings for underground use are cheaper than the black or grey. The brown pipe does not have UV stabilisers in it, which is why it is not good to use it outdoors. In a workshop, it would probably be OK.

Floplast has catalogues for both applications that list what is available.

 

[Yojevol]

I ran an extensive soil pipe system for 20 years without any functional problems. I used basic 90deg bends. You have to be a bit inventive when connecting 110mm soil piping to 100mm DX kit like blast gates. I made my own connectors by cutting off a short length of soil pipe, slitting it lengthwise and removing a bit of material (probably up to 10mm). Close the gap and bind with duct tape. Fix to the unit with pop rivets.
If I were doing the job again I would seriously consider lightweight air conditioning 100mm pipe such as this. A point to note here is that the AC nominal size relates to the OD whereas the 100mm DX stuff is ID. I think that's right, anyway they're not compatible but its easy to make connectors as above.
Brian

 

[hlvd]

I modified one our machines at work with a couple of plastic blast gates but they failed the yearly test as they had to be steel/cast aluminium.

I can’t remember the exact reason but I think it was to do with static and that they couldn’t be earthed.

 

[dvddvd]

Had a read up on static explosions etc and it seems in a giant workshop with a giant size extraction it may be a problem but in a blokes shed in his garden running it for 5 mins max it's never going to be a problem.


Apparently it was on the American show myth busters and they decided it was just a myth?

 

[Housey210]

There is a reason why the health and safety executive have guidelines on this.

 

[macca]

couldn't you just tie some cheap copper wire to a tennis ball and send it on the maiden voyage of the system, attach it to an earth pike and any static would be negated? just don't forget to tie the other end to something first


If we're really going OTT on the health and safety should we all install sprinkler systems in the dust collection bin? I imagine a blunt router bit making an ember delivered straight to a huge pile of fine sawdust mixed with copious amounts of oxygen could be interesting

 

[Sachakins]

You can long swept bends instead of the normal 90° bends, like these at screwfix

​

 

[dvddvd]

There is a reason why the health and safety executive have guidelines on this.

Is that for full workshops with multiple staff, working 8 hours a day or the single bloke in his shed spending 5 mins on his router table?

 

[PDW125]

Cheap copper tape down the inside of the ducting (stuff they use to prevent slugs) will create enough of a path for any static to be eliminated - just earth it at one end to the workshop power (attach to a metal conduit)

Also worth getting some cheap j cloths and making a loose ragged ball and spraying liberally with pledge or SWMBO’s favourite brand of furniture polish and sending that down every duct to start with to reduce static build up in the first place.

 

[Terrytpot]

If I ever get around to making that much geezer glitter and decided it was time to install some ductwork I don’t think I’d be looking at plastic choices as from what I’ve seen they aren’t ridiculously cheap whereas the pucker stuff doesn’t strike me as being horrifically expensive.
If you’re wondering who to try.. check out dust spares , and no, I don’t have any affiliation with them , I’m just a happy customer who got his flexible hose from them.

 

[Daniel.l]

I put in a 160mm soil pipe duct system last year it works very well with homemade blastgates. I connected the soil pipe to one side of the blast gate and a white 150mm ducting pipe to the other end because the flexible hosing slips over it nicely. The same would work with 110/100mm I assume. Regarding static I watched this youtube video who explains it very well I just grounded the pipe and touch points. I also used lots of 45 degree bends with no 90 degree bends in my system. Two 45s is a lot better than a 90. Y-Junctions were used at drops with a 45 to make it 90 degree down. Also shop around I made a serious saving buying all the junctions at one shop and straight runs somewhere else

 

[Graham Brazier]

I’ve just done similar in my garage using the 135deg Y connectors and the large sweeping 90deg bend along with a few 45 deg

I made my own blast gates

One long pipe and then dropped down to my table saw and extractor but added a few branches for poss other machines but blanked them off for now

The pipe is great but hard work to get apart if you change ya mind re pipe placement

The motor is up in the rafters of the roof with the 110mm pipe connected to aporox 1m of 125mm pipe straight to the extractor and then outside in to a collection bag /box

You can get 110-100 adaptor also for attaching 100mm flex pipe

Added a remote switch also bypassed the NVR switch bought from Amazon
Fox 2Hp extractor