Who can help me build a home made dust collection system???

[Paul Cataldo]

Guys,
First off, would like to say Hi, as I'm new here. I hope I can find useful information from this great forum.
I am a beginning knifemaker, and need to design a home made dust collection system for my basement shop. I will be grinding titanium, s30v steel, and other steels as well. The major issue I have is with grinding handle materials such as carbon fiber, micarta (toxic dust in micarta) and G10. G10 is also toxic dust, as it is woven fiberglass and epoxy mixed to form an ultra hard almost indestructible substance.
I am about to get a brand new Bader III belt grinder, and that will just about complete my shop setup for knifemaking, except for a good ventilation/dust collection system.
I have read about guys using squirrel cage blowers from HVAC systems. Upon ALL my searching, I still have not seen any case where someone brought up the fact of all the toxic dust being blown right over the squirrel cages' motor. Is this going to be a problem?
I am still trying to figure the best way to set up a system. Should I just run some metal ductwork to the grinder, and mount the squirrel cage IN-LINE, with it blowing outside? It seems this way, I would not have to worry about any fires or sparks catching fire to anything (for the most part anyway). I would LOVE some tips on doing this type of system. ie - what type of ductwork to use, size of ductwork, etc. Any other tips on this system? Has anyone HERE on this forum actually done this method? I would be FOREVER greatful to anyone who has some pics of a home made system such as this.
My ONLY concern with the "squirrel cage" system, is replacing the air that gets blown outside with new air. I don't want to just crack a window on the other side of the basement, and suck tons of cold air in, during winter months.
What should I do guys? If you guys help me out here, you will surely save the day fellas!! LOL!!


[This message has been edited by Paul Cataldo (edited 01-30-2005).]

[wierdscience]

Hi Paul,welcome aboard!

Okay,dust collection,I have much experience with that subject.
The most bang for the buck are the import dust collectors for woodworking.They are a radial fin type blower capable of high voume and static pressure.
Squirrel cage blowers are high volume low pressure and not sutable for dust.The small blades load up with material and effeciency drops.Not to mention the air over motor problem.

I can recomend the units Grizzly sells,they are well built and durable.For about $150.00+ frieght you can be in a system including filter bags.Depending on the micron size of the particles your are dealing with the bags themselves may be enough of a filter.If not HEPA filter cans are availible.

If you are limited on resources,Lindsay publications has a book by Dave Gingrey on building centrifugal fans,it is easier than you think.

Okay hoses,flex hoses and pvc pipe can be used so long as the piping and hose are grounded to eliminate static.

[Paul Cataldo]

Yeah, thanks bud. I've seen some who use a Grizzly dust collector. I just really was worried about the sparks from metal catching the filter on fire. Just have to use an inline fire suppression box or some type inline water bucket to catch them.
I was also worried about shooting the air back into the shop, EVEN IF A HEPA FILTER IS USED. I was just a little concerned about breathing the filtered air over and over again...
Any more suggestions guys??? Thanks.

[wierdscience]

Well you could make a wet filter.Just a 55 gallon drum full of furnace filter material and a pump to mist water into the air stream,this will work even on paint overspray.You may need to oversize the collector and also use a secondary filter to trap the extra moisture in the exhuast.

[torker]

Weird...what about a cyclone...set it on top of a 5 gallon bucket of water and keep the water level real close to the bottom of the cyclone...no sparks to worry about and a lot of the dust should end up in the water due to the centrifical action of the air. 5" or6" furnace ducting would work fine...you could even rig up a "thumper" on a timer to knock the little explosion causing dust mites loose. You might also want to pipe fresh air into the inlet were it hooks onto the machine. Thats how we've done a few up here in the cold climate. The unit will suck what ever air is easiest..if it's sitting right there it has no choice. That's actually how my NG furnace is hooked up as well.
Russ

[wierdscience]

Sure,that would work,heck you cou;d even induce water mist into the inlet of the cyclone and have it and the dust drop out the center,might take some spearmintin thou.

[ibewgypsie]

I have several of the Gast type blowers. I rigged one 1/2 hp unit up in my shop exiting the air from over the mill. Coolmist is causing some problems in my shop (I have soem book shelves full of manuals), I was also trying to use the cnc as a flamecutter (bad ideal) It has 1 1/2" pvc pipe ran to it.

What I noticed, the neighbors thought I was playing the the steam rocket again. They thought it was a whistle. It howls like a jet turbine. I have two mufflers but they are quite heavy and I did not install them on the pvc exhaust, yet.

The heat inside my shop, once you turn it on is "GONE". exits the building like Elvis. It got dreadful cold in there in a matter of two minutes.
The units I got were for scrap yarn lint collection. No filter came with the junk I got. I plan on reworking a barrel, remounting one of the blowers further away from my shop on a pad next to the hydraulic unit I have not mounted yet. Kinda like you just suggested there.

A genie 4hp vacuum will suck the swarf off my mill table, I don't think the motor was made to run continous thou like these blowers are. Check the motor nameplate, it should have a duty factor (running time) of 1.0 (full time) or 1.1 (heavy load full time) to be a continous service motor. Normal vacuum cleaners are not.

[Rich Carlstedt]

Hi Paul
I have a Sears shop vac outside.
2"PVC pipe in the floor, but you could run it overhead.
I have a 20 gallon (Grease Drum) set up with a vortex(Centrifical seperator) to keep most of the stuff in the drum.
This allows me to suck up all chips..
If the chips are wet, I stick my normal wet/dry vac inbetween..Outside suction is put in the wet/dry EXHAUST, and then i really have some pull if I run the Wet/Dry vac at same time.
The important thing to me ? NO DUST In THE SHOP
Rich

[CharlesM]

There is loads of information on wood working dust collectors on this site:
http://cnets.net/~eclectic/woodworki...lone/index.cfm

It also has plans to build your own. I just completed a system built from his plans. It works great. Almost zero dust goes to the filter, almost all drops out of the cyclone.

[Michael Moore]

There was a thread over on PM a couple of days ago which might give you some additional info.

http://www.practicalmachinist.com/ub...c;f=1;t=009095

cheers,
Michael