extracting mdf dust

[prawnking]

i know i have already asked similar questions but i am still not quite shure what to get for the best.
so here it goes
i have read a lot of threads on dust extracting and what extractors and vacs everyone has,
i now understand i need a dust extractor and a workshop vac. now here is where i am confusing myself, by my understanding dust extractor draws a higher volume than a vac also has a larger capacity for the dust ie longer b4 you got to empty it.
does a dust extractor filter finer dust than a vac? (i know its down to what vac you buy i have already been looking). what level of filtration will i need?
what filtration will satisfy mdf which i believe is the worst and finist needed to be filtered?
also any recomendations on machines ive been looking at b&q `s workshop vac £60 with 1800w power takeoff.
also rexon de1000 dust extractor
any coments?
:? :? :?

 

[woodbloke]

Much has been written on this topic, a good general guide is to be found in the APTC catalogue on page 1.108. The range of products is broken down into the following four Extraction Performance Ratings
1. Chippings only
2. Chippings and sawdust
3. Chippings, sawdust and sanding dust
4. Chippings, sawdust, sanding dust and MDF dust

If you have a trawl thru' the catalogue you will probably find something that suits your needs and pocket - Rob

 

[prawnking]

dont want to seem stupid but APTC catalouge?

 

[Scrit]

Hi

This is a very thorny question indeed. Rather than try to encapsulat it in a simple answer may I refer you to Bill Pentz's excellent site on dust extraction? Bill has tirelessly put more work into dust extraction research than almost anyone on the planet - with the emphasis on small workshops, and his site even includes plans on how to size and build a dust extractor.

The problem is that what many of us call a "dust extractor" is, in fact, a chip collector with inadequate filtration for fine materials. To filter-out MDF dust you need to go down to sub 2-micron filtration, something that most chip collectors and vacuum cleaners simply cannot do - they catch the bigger stuff and pass the finer stuff straight back out into the air you breath. At the same time as adequately filtering the exhaust air you need to shift enough air both to keep the cutter area clean and to ensure that the dust produced by the machining process ends up in the extraction system and not the air around the machine and your lungs. In real terms that translates into a largish vacuum cleaner being adequate in many cases to extract the dust from a portable saw or router machining say 18mm MDF, providing you can get a fine enough filter for the vac, but the same vacuum cleaner would probably choke at the load it would have to handle if you connected it to the outlet on your thicknesser. It would probably also fill-up in about 15 minutes at most.

When you get to static machine such as table saws, spindle moulders,static sanding machines, etc. the amount of air you need to move (and filter) to keep the working environment clean escalates dramatically and at that point you need the air volume that a "dust extractor" can deliver. However, here's the catch, most low-cost woodworking "dust extractors" (i.e. those ship collectors under about £1500, really!) struggle to filter anything below 30 microns in size unless you resort to replacing the filter bags with fine non-woven bags or even pleated cartridges. So if you need to extract a couple of static machines it's either a case of dig deep, or go the DIY route and modify or even build your own cyclone extractor a la Bill Pentz.

If it's any consolation this is a big problem even for people in the trade, too.

Scrit

 

[Alf]

dont want to seem stupid but APTC catalouge?

Axminster Power Tool Catalogue.

Cheers, Alf

 

[prawnking]

thanks woodbloke i am getting there slowly

cheers scrit that information helps me to understand a little better

thanks alf sorry if it seemed a dumb question.

 

[ProShop]

Having posted a fair bit on dust extraction on the forum I can only endorse what Scrit posted above including the Bill Pentz site which is a mine of useful, factual, & informative information.

If it helps you any, 0.5 microns is classed as hospital cleanliness. So that's a good target imho to aim for (especially for MDF)although as Scrit mentions you may have to dig deep for it. Most dust extractors (chip extractors) are called dust recirculators as they collect the chippings & dust together then seperate them & drop the chippings in a bag and blow the fine dust back into the workshop & most of this dust is so fine you can only see it if you switch the lights off and shine a torch beam into the room.

Most good bench saws & planers etc give guideance to air volume extraction rates needed, measured usually in cubic metres per hour, another important measurement is static pressure,(usually measured as PA). get that lot right & your on your way to a clean air workshop.

Hope this helps.

 

[engineer one]

not sure about your budget, but the trend vacuum with the mdf filter is
about 170, but is designed to draw fine dust model has suffix AF

i have found it great for both mdf dust, and also plaster dust.

of course will all these things it all falls down, when you have to
clean out the body, or change the paper bags,, or even worse,
clean off the paper filter.

works well, and is quite quiet.

paul :wink:

 

[Barry Burgess]

As Scrit said read the Bill Pentz website. I am at present building a cyclone but in the interim I am using a 3HP dual bag system. I have replaced the lower bags with plastic and used gaffer tape to prevent leakage from the bags. I bought two pleated 20 m2 filters that filter to .5 micron and built a mdf and stud device to hold the filters in place similar to one of the links on Bill's site. What a difference - just complete the job this weekend. The extractor works much better - the suction has improved as the air has more area to escape and the fine dust blown out of the top bags is removed .
The filters were £47 + VAT each - well worth it.
I have found that shop vacs are more suited to hand tools but lack the flow rate for tablesaws ,thicknesser etc. To get the flow rate with the extractors even with a small workshop a 3HP motor is required.
My only regret is that I did not run 150mm pipe as the main trunk, I used 110mm soil pipe.
Barry

 

[Alf]

thanks alf sorry if it seemed a dumb question.

No such animal - no-one's born knowing about APTC. At least not as far as I know... :wink:

Cheers, Alf

 

[prawnking]

i am in the middle of reading bill pentz website, i cant believe how much dust can affect your health if not controlled properly may be it will be worth investing a fair bit into a tidy dust extracting system form the start rather than buying then upgrading on and on, will be better for health and cheaper in the long run.
i think i will buy the trend vac af with fine filter just to get me started though, i might attempt to make a cyclone or am i going over the top for a hobby workshop?

cheers for your advice
shaun

 

[Scrit]

I am in the middle of reading bill pentz website, I can't believe how much dust can affect your health if not controlled properly may be it will be worth investing a fair bit into a tidy dust extracting system from the start rather than buying then upgrading on and on, will be better for health and cheaper in the long run.

My late father was exposed to hardwood dust (mainly teak, mahogany and sapele) in a occupational therapy workshop over a 7 or 8 year period in the late 1950s/early 1960s. Granted they had poor extraction in those days and masks were almost unknown, but that period of exposure was enough to leave him with respiratory problems for the rest of his life, resulting in several stays for treatment in Benenden Hospital in Kent in the 1980s. Towards the end of his life he needed to have an oxygen bottle near at hand all the time because the exposure to dust had so badly damaged his lungs. Exposure to wood dusts affects each of us differently but prevention is probably much better than (no) cure.

Scrit

 

[ProShop]

i think i will buy the trend vac af with fine filter just to get me started though, i might attempt to make a cyclone or am i going over the top for a hobby workshop?
shaun

imho," are you going over the top" the answer is no your not. Quite a lot of people see extraction as a un/neccessary evil & expense.

I see dust extraction as a serious investment in my future.

___________________________________

Scrit's post above makes very sombre reading indeed and serves as a poignant reminder to use modern technology and better information that is available today to look after our health better.

 

[ivan]

Barry, where did you find the 20 sq m pleated filters for £47?

I have been thinking of improving my filtration. (presently a 6' high singed polyester felt bag over a metal bin) which keeps back most MDF dust if cleaned daily - a dusty old job...I was thinking a drop box might do. According to a heating/ventilation eng. handbook I found in the Exeter reference library, this can do as well as a cyclone for fine dust.

 

[Barry Burgess]

Ebay listing
They have a number of other filters that will work aswell.

 

[prawnking]

so whats every one opinion on buying or building your oqn dust extractorby dust extractor i mean any thing that can filter even mdf dust without loss of suction,
can you buy cyclone dust extractors?

 

[King Corragate]

Hi im new to the forum,but im supprised CamVac as not been suggested.Ihave had a wall mounted single motor unit fully plummed into my workshop now for 2years and it works well with all my machines.The 2 stage fillter seems to cope well with MDF dust. The only minnor problem is the blast gates at each outlet must be cleaned to ensure they close fully or you loose a lot of vacum.

 

[prawnking]

camvac where can i get info on them does it filter to 0.5micron

 

[Jake]

Camvac are here: http://www.camvac.co.uk/

Yes, they filter to .5 micron as standard - through a cloth sack then through paper bag filters over the motor(s).

I've got one and it's a great machine. They aren't cheap though, especially the multi-motor ones. Other minor quibbles are that they are very noisy and you can't tell when the drum is full unlike a see-through sack.

Very effective though.

 

[prawnking]

jake
looks like they sell camvac in data powertools theres one not far from where i live will go and take a look
what one you got?
how much roughly did you pay?