Thread: Dust Extraction

I'm no expert here but your pipes are too small for a start. And the 90 degree join would be a bugger for good clean flow. You want smooth bends.

Hi, and welcome
Your ducting is waaaaaaaaay too small.
You have to use 100mm or whatever you inlet size to your dusty is.
Dustys rely on air flow to make them efficiant, not suction as do vaccumn cleaners.

See all the spots in you photos?
That is airborne dust.
And you are breathing it.......:eek:

Al :eek:

thanks so far for the comments. Makes sense about air flow and not suction. When i was putting this config together first i kept testing it like you would with a vaccum by putting hand over it, seems i had my hand on it thinking it would be better, haha

Thanks for the quick replies as well

By the look of your pics you are running a Hafco 7 which sucks 2300CFM (when its not strangled).
Mate if you want suck then change to 5" main lines (or 6" even) with 4" droppers to your machinery.
Just dont let small children or small dogs near any of the inlets

I have a 2Hp 1200cfm Jet. I've been running 4" PVC pipe for a while, and it worked OK. I've just replaced the main lines with 6" PVC and it works a LOT better.

Dust extractors rely on a lot of air flow to work right - and you just don't get that with pipes that are tool small.

Here's the best site for everthing about dust collection http://billpentz.com//woodworking/cyclone/index.cfm

Take your time, it takes a long while to read it all, but it is worth it. Also check out the best of the best section of this forum for other tips.

Cheers.

G'day NidekFurniture,

Mythbusters a while back now had an episode testing the myth of static electricity on PVC causing a fire and as they do they tested to the point of going way out and proved it to be "Busted"

Gee, thanks for the tips guys. First thing this weekend ill be ripping out the existing pipes and laying down some big fat suckers. Ill post some pics when ive finished to let you know how i got on.

Very helpful information from everyone, thanks a lot. Amazing what you learn if you ask.

Cheers.
Nick

Thats the same extractor as I have... go 6" as far as possible to your machines. I've got mine set up with a overhead 6" mains(bout 8m long) with 4" solid(no flexi)SWC drops to my machines 7 offtakes in all can run 3 at a time no worries very good flow. With 4 offtakes open at once the flow starts to drop off...

[QUOTE=NidekFurniture]

And whats this i hear about earthing the piping? anyone heard of any fires actually starting from static?
QUOTE]

Static electricty generated by the movement of air by itself would not normally start a fire with wood dust or shavings, but it will if there are some readily combustible fluids already sitting at their vapour emmitting flash points ie
:eek: petrol - flash point -40 deg C
:eek: mineral turps - flash point 31 deg C
:eek: methylated spirits - flash point 13 deg C
and these become very danergous when sitting in a rag or other material which increases the air to material surface area.

Originally Posted by Waldo

G'day NidekFurniture,

Mythbusters a while back now had an episode testing the myth of static electricity on PVC causing a fire and as they do they tested to the point of going way out and proved it to be "Busted"

I'm sure that's correct, however I can attest to the fact that whenever I am connecting the 4" flex tube from the running DC to an earthed tool, I get a big belt of static - when humidity is low and I'm wearing the right/wrong boots that is.

All good, i managed to get some piping from a mate who had "borrowed" it a while ago from somewhere. Ill post some pics up when i have done it all.

Originally Posted by Bodgy

I'm sure that's correct, however I can attest to the fact that whenever I am connecting the 4" flex tube from the running DC to an earthed tool, I get a big belt of static - when humidity is low and I'm wearing the right/wrong boots that is.

You wear boots in the shed? :confused: And your tools are earthed, :confused: :confused:

Wow, i guess it takes all sorts.

Originally Posted by Harry72

Thats the same extractor as I have... go 6" as far as possible to your machines. I've got mine set up with a overhead 6" mains(bout 8m long) with 4" solid(no flexi)SWC drops to my machines 7 offtakes in all can run 3 at a time no worries very good flow. With 4 offtakes open at once the flow starts to drop off...

Any chance of some pics of your setup, especially hooking the main pipes up to the extractor? ive got some pipes now, but just wanna be able to see how you have connected it up to everything in the way of bends and stuff to take into consideration.