Air Filter construction

[Anonymous]

I'm interested in making my own air filter, along the lines of DaveL's. The construction is straightforward, and you can size it to take the Axminster filters, but what do I need to look for in terms of a fan? DaveL was lucky enough to have one already.
Is there an output volume/min or a kW rating that anyone could recommend? Would a redundant vacuum cleaner motor and fan be suitable (SWMBO wants a Dyson and I could cannibalise the old one!)

 

[devonwoody]

The goodwoodworking magazine did an article sometime ago perhaps there might be some info there. Cannot tell you which issue is was.

 

[DaveL]

Hi tycho14,

I have been looking around for a source of fans and not had much luck.
Most vacuum cleaners are a bit on the big side for an air filter. You only need something in the 50 to 100 watt region, quite low power. The other thing is the rating, you need something that is continuous rated, you need it to run for hours non stop. Domestic vacuums are not rated for continuous use they will get very hot if run all day.
I think the fans used for warm air central heating units or air conditioning units are a good choice but I have not found a source for them yet.

Equipment cooling fans are good but a lot of them are now only a few inches in size and low voltage. The fan I used is quite old, made in the seventies, a good decade from what I remember.

 

[llangatwgnedd]

How about using the motor and impeller from a tower fan

Link

Cheers

Mod edit for long, scroll-inducing link

 

[The Wizard]

The Good Woodworking issue in question is issue 150. Unfortunately the article is in the section Thoughts From Abroad(America) with no reference that I can find to where we can source fans from in the uk.

Regards

The Wiz

 

[The Wizard]

Got a bit confused there :? . There are two sections on dust filter assembly. The other unit they made utilised a 100W squirrel cage fan from Electricaire (01698 844180).
Hope this helps.

The Wiz

 

[garywayne]

Der, whats this air filer for?

I'm not asking so as to answer. I don't know what your talking about. (excuse my ignorance).

Sorry to but in.

ATB Gary.

 

[DaveL]

Gary,

Its a filter that is used to remove the fine dust from the air in the shop instead of using your lungs to clean the air.

Take a look here to see what I made.

 

[garywayne]

Thanks, Dave.

I suppose thats something else to add to the workshop build & contents list. Good idea.

ATB Gary.

 

[devonwoody]

Fans,

What about the Expelair type kitchen/bathroom fans, our seems to runs for many hours when conditions are damp?

The Expelair is an expensive fan but our local electrical supplier has cheaper models which I should have thought are continuously rated, any comments?

 

[Anonymous]

Thanks for all your advice, guys. I think I know where I'm looking now. Cannibalising a cheap fan might be a better option than a more expensive industrial fan. I shall make some enquiries and let you know how I get on. Thanks again for your input.

 

[RogerS]

I picked up something like this off eBay http://rswww.com/cgi-bin/bv/rswww/subRangeAction.do?cacheID=uknetscape

Mine was encased ready to screw into a 19" rack and cost me about £13. Not in the filter unit yet...slowly making its' way up the TUITs.

Roger

 

[RogerS]

I picked up a tangential fan (used in 19" computer racks) off eBay. RS have similar units..

Mine was encased ready to screw into a 19" rack and cost me about £13. Not in the filter unit yet...slowly making its' way up the TUITs.

Roger

 

[devonwoody]

Roger

Are you saying the fan unit type that is in my PC?
I think my one runs through a transformer?

 

[RogerS]

No, DW..nothing like. This is what I had in mind
http://www.dataracks.co.uk/products/elite_thermal_solutions.pdf

Although DaveL's fan is better suited...but not so readily available that i could see.

Roger

 

[Woody Alan]

Roger/DW

In the course of work I frequently work on 19" racks for ADSL and part of the commisioning process involves disconnecting one of the fans in the fan tray to get an alarm. These trays sometimes have 4 fans and some 8 fans. They are in fact very like the ones in your PC except instead of being plastic they are alloy cast body with proper ballrace. I'm not sure of the voltage of our particular ones but they'll be 50v or less. Anyway the point I'm eventually coming to is that they make an unholy din when all running together. if this type/size of fan is to be used perhaps a group of cheap PC fans could be tried but a resisor put in series (with the resistor in the airflow to cool it) so the air movement is obtained without fan speed and hence the noise, but a 12volt supply would be needed. Another alternative might be a cheap desk fan, shrouded and modded, but again they generally have a bronze/brass bush, which dries out and needs lubing from time to time (I have to do the lube thing on the PSU on the PC in the workshop from time to time)
I asked the wife if I could use the variiable speed extractor from the cooker hood, but she seems to think it's already required in it's current situation...Oh well.
noise info here http://www.cpemma.co.uk/

Cheers Alan

 

[frank]

i got a 6"wall fan of ebay for under a tenner it will move 220m3 an hour i hope to make a box to fit it in this week i will be using a replacement filter from one of those round hanging filters .my old filter is a 3 speed desk fan set in a box .

 

[devonwoody]

Frank:

Please keep us posted I myself would like to hear your evaluation of the completed project.

 

[gav]

I've been considering doing something similar following the DaveL article and have just acquired a set of fans like these from an old rack. Even had to cut the tie wrap off the cord as they had never been plugged in

http://www.dataracks.co.uk/products/rooffan.htm

They are mains and continuous rated. They seem very reasonably quiet when running compared with other noises in the workshop.

Gav

 

[beech1948]

errrrrrr......guys are we not being too quick here to select the fan type or types. Isn't the first question-------How much air does the fan have to be able to move to work satisfactorily.....

If so...how much and how fast....