extracting mdf dust

[Inspector]

Brad

We seem to belive the same thing but for slightly differing reasons. While fire should always be considered I think the friction of the dust hitting and causing a hot spot is a non issue as there is a steady stream of air blowing across the same surface with it's cooling effect. The easiest way to get an inkling of whether there is some cause for concern would be for someone that has a cyclone (perhaps Barry) feel the top of their metal one where the dust enters while it's sucking up a big pile of chips to see if it even begins to get any warmer than the surrounding areas. If the metal stays cold, as I suspect it will, then a wooden one isn't likely to behave much differently.

I'd like to find that Physicist though to find out how the static producing properties of a wood cyclone and ducting compare to other materials such as plastics? I thought that would surface first as a concern of people rather than of friction induced fires.

 

[Scrit]

I can tell you one thing for certain - dust extractor cyclones, plenum chambers, etc do not get even slightly warm. The constant flow of air must see to that.

Scrit

 

[engineer one]

from what i have read elsewhere, the risk of fire is much more to do
with static electricity build up, and this is actually less likely in natural
products like wood, or even metal. plastics however seem from
reported evidence more problematical.

obviously if your air flow is fast enough then the bits will not get
stopped in the odd corners where they could build up and cause
friction.

personally i am still not sure that cyclones are the answer, still
awaiting some evidence from something else we are doing.
i am in awe of what barry has done however, and think it is a good
test device.

i do however wonder whether there is a simpler way???

what really intregues is the need for worrying about large lumps of material if we are cutting mdf on a router/table saw/ etc.

paul :wink:

 

[Inspector]

Scrit you're a Physicist too :?: :?: :?: :lol: :lol: :lol:
Honestly, thanks for the backup. As a rookie to this forum my word doesn't carry as much weight as yours.

 

[Barry Burgess]

a
I have an improvement suggestion to your system if you're interested. If you reduce the length of the 6" flex hose you would increase the airflow in the system. Take the entire "dusty" and turn it upside down and hang it off the wall/ceiling/or mount it on it's own stand. This will put the inlet of the blower close to the outlet of the cyclone and reduce the 6" flex hose to a few feet, and if positioned right may eliminate all the bends in the hose too. repositioning the unit will also require flipping the canister/bag/mounting ring assembly to keep the canisters on top, but that is only 4 bolts at the top on the square flanged pipe coming off the blower.

This is the next step for me. I have already built the filter stand and a baffle to reduce the noise. The debate at present is either to suspend it from the roof rafters or side mount it on the wall. I also can't decide if I will replace the impellor case from the extractor with a Pentz's designed one. I have cut the top and bottom of the impellor case and got the bolts required. The current stand will allow the impellor to be mounted on top of the cyclone.
What I don't want now is to have the workshop out of commission during the good weather. I will likely do it in October or run out of projects to do.

 

[Barry Burgess]

This is a picture of the final bits for the cyclone

The filter stand has a blast gate at the bottom to collect any dust that passes through the filters.
I need help testing the baffle. It has a 6" inlet and a 6" outlet. I have used PVC pipe for the body to reduce the noise. It opens out to 12" and the through pipe is 6" and the noice reducing materials are wrapped around the pipe. A funnel at the top allows the air to expand from the 6" to use the full 12" of the baffle. The baffle would be installed after the impellor and before the filters. In theory the baffle should reduce the noise by upto 10db??
If you can help me test this baffle could you PM me.
Thanks again
Barry

 

[Inspector]

Barry
I didn't realise you had the other components on the go. What I meant was if you stand back and look at your collector as it sits with the filters and bags, the entire unit gets flipped upside down. Pop the castors off and screw the base platform to the ceiling. Then unbolt the 2 square flanges at the top of the "Y" and swap them around so that the filters stand along side the blower. With help to lift, it wouldn't take very long to do. If my previous post was understood then excuse the repetition.

 

[Barry Burgess]

Barry
I didn't realise you had the other components on the go. What I meant was if you stand back and look at your collector as it sits with the filters and bags, the entire unit gets flipped upside down. Pop the castors off and screw the base platform to the ceiling. Then unbolt the 2 square flanges at the top of the "Y" and swap them around so that the filters stand along side the blower. With help to lift, it wouldn't take very long to do. If my previous post was understood then excuse the repetition.

I saw where you were coming from but with the filter stand made and wanting to use the baffle I gave up on your idea. With my current roof height, the motor will be above the roof rafters. I think I will complete the impellor case next then decide when and what to do.
Thanks
Barry