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Dunc
12-31-2008, 11:21 AM
"Vacuum is the newer tech but quite pricey as the typical shop vac ainít going to deliver the cfm needed to make a good show of it."

Above was posted by JoeFin in a reply to a post about aluminum swarf galling on end mills.

Not wanting to hijack that thread...

Wondering if anyone could fill in the blanks about what "is" needed. What sort of cfm (could a lack be compensated by using a smaller nozzle - yes, it increases the velocity but not the cfm), how to protect the paper air filter from a death of a thousand cuts, and what happens in the container: after all, there is a gooey mess of various metals, cutting fluids, etc.

rockrat
12-31-2008, 11:35 AM
CFM? I could not even venture a guess without a bit of trial and error. However, they do make a canister that can be added between the vac and the point were the chips enter the hose. The idea is that when the chips get into the first can they fall to the bottom and the vac continues at the top. A separator of sorts.


Click for larger photo.

http://images.rockler.com/rockler/images/27351-03-80.jpg (http://images.rockler.com/rockler/images/27351-03-500.jpg)

rock~

derekm
12-31-2008, 11:48 AM
"Vacuum is the newer tech but quite pricey as the typical shop vac ain’t going to deliver the cfm needed to make a good show of it."

Above was posted by JoeFin in a reply to a post about aluminum swarf galling on end mills.

Not wanting to hijack that thread...

Wondering if anyone could fill in the blanks about what "is" needed. What sort of cfm (could a lack be compensated by using a smaller nozzle - yes, it increases the velocity but not the cfm), how to protect the paper air filter from a death of a thousand cuts, and what happens in the container: after all, there is a gooey mess of various metals, cutting fluids, etc.

The best approach is a cyclone to knock down the fluid and swarf before the bag filter. I managed to find a packaged one in a Dyson (which have a high CFM) SWMBO was throwing out. I use the down the back of sofa nozzle. You can easily make a cyclone front end for a standard shop vacuum which was my plan before the dyson fell into my lap.

A simple cyclone is just a special version of what rockrat has, but with a specific inlet and out design so that the gas swirls around and exits from the centre.

airsmith282
12-31-2008, 11:55 AM
my shop vac works great its a cheap 5 gallon one i got for 5 bucks at a yard sale.
i never had an isse with the paper filter getting all cut up , but the elastic that holds the paper filter on finelly broke so i gave up- and use it as is ..
it still has the sponge screen on it and seems to be just fine.

been using this shop vac for a few years now suckingup metal and all kinds of stuff and its still running so iam not to worried about it ,, my next shop vac is going to be a job mate one just for that simple fact iam over run with tools in my shop that are now hangin off my celing so i need a more complact shop vac now untill i can afford to build a larger shop..

if you got holes in the hose thats going to ruduce the power alot try a new hose if you gota problem might just help also i always take long and med strings out of the way before takeing the vac to it all other wise it clogs up the hose alot

Rustybolt
12-31-2008, 12:38 PM
Dunc. I don't know ,but I use my dayton 10 gal. shop vac to suck up plastic and laminate swarf on the mill as I'm milling. I does a great job with the smog as well. I have a nozzle attachment which I think you can still get from Grainger. It is a nozzle that goes from the diameter of the hose and tapers down to about a half an inch. Very useful for getting the swarf out of the T-Slots. it seems to incrase the velocity. Maybe that would help.

tony ennis
12-31-2008, 12:48 PM
My floor is asbestos tiles. No vacuum for me. A pinhole in the filter and whatever asbestos dust is there gets ejected at 10000000 mph.

I really need to paint it, or something.

Teenage_Machinist
12-31-2008, 01:12 PM
Ishamura made a cyclone. Check it out.

BillH
12-31-2008, 01:20 PM
I'm going to make my own seperator with a 5 gallon pale

Circlip
12-31-2008, 01:52 PM
This seems to work quite well

http://www.cgallery.com/jpthien/cy.htm

Regards Ian

Forrest Addy
12-31-2008, 02:55 PM
If you're thinking of a central dust collection system to serve several machine tools with permanently connected duct I'd reccommend against it. It would be a mantenence nightmare because of the down time necessary to clear clogs. However a box store shop vac serving an individual machine is a real time saver especially if you make a chip pickup easy attached (and detached) at the cutter positioned to snuff up chips as they are generated.

Also have a length of electrical conduit handy to poke through the hose when needed.

I've had a shop vac at my milling machine for 20 years and it's one of the best time and hassle savers I've ever made. It's a cheap Sears vac dedicated for the mil. I never use compressed air on the machine except for clearing blind holes. I pick up all the chips (except twisty drill chips) with the vac. Saves time. Vac = handle chips once. Air = handle chips twice: blow off/scatter chips; sweep up chips/clean machine.

One thing. Never use a chip vac for general dust pick up. Once the filter begins to plug the suction CFM halves and reduces its effectiveness for chips. Buy one and dedicate it for chip pick up.

A tip. You will reduce number of clogs if you routinely fluff the chips as they are vaccumed up. A stream of individual chips will flow down the hose. A clump may snag. Clumps equals clogs.

Rustybolt
12-31-2008, 03:15 PM
Tony. There is less than 1% of asbestos in those tiles and that is encapsulated. I found this out after I paid a company to remove 2500 square feet of tile from a shop floor. Afterwards I talked to several environmental engineers who told me that asbestos abatement of floor tiles was a great scam.

andy_b
12-31-2008, 03:23 PM
A tip. You will reduce number of clogs if you routinely fluff the chips as they are vaccumed up.

just what my shop needs, a dedicated fluffer. i already have one in my house. :)

andy b.

Robin R
12-31-2008, 05:13 PM
I found a quick release magnet a big help with longer ferrous chips, $13.50 from Lee Valley. http://www.leevalley.com/wood/page.aspx?c=1&p=32072&cat=1,42363,42356&ap=1

Steve Stube
12-31-2008, 06:02 PM
I picked up the type Robin R shows at Harbor Freight ($3.90) IIRC. They don't seem to have that version online now (at least I didn't find it) but they do have this long reach one that I'm sure will be handy - gotta get me one!

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93950

quasi
12-31-2008, 08:20 PM
just what my shop needs, a dedicated fluffer. i already have one in my house. :)

andy b.


mine has become less and less dedicated over the years, to the point of total indifference.

danlb
01-01-2009, 01:46 AM
I have a little 3 gallon shop vac that follows me from tool to tool.

The best improvement I've ever seen was to add a flexible smooth vinyl hose in place of the pleated one that came with it. The hose mates with the original hose fittings perfectly. Because it is smooth-bore, the swarf (even long stringy stuff) is sucked straight down. It has not clogged more than two or three times in 3 years.

The hardware stores sell the vinyl tubing by the foot. My 8 foot section was only 5 or 6 bucks.

Dan

noah katz
01-01-2009, 05:18 AM
"The best improvement I've ever seen was to add a flexible smooth vinyl hose"

Is this just plain, unreinforced tubing? I thought it would need something to prevent collapsing.

Your Old Dog
01-01-2009, 08:30 AM
I just use a Craftsman 20 gallon vac. I discovered quite by accident that I could severely reduce plug up time by heating my nozzle with a heat guy and flattening it out so it fit into my mills table slots. I haven't had one hose plug up since I did that over 2 months ago. Long aluminum lathe and drill press ribbons are picked out by hand and not vacuumed.

Someone recently posted their idea to put additional dust back on the output from the vacuum to catch anything coming through the main filter. I plan on doing that as well because every once and a while my bag gets pierced and I end up eating dust! He used PVC adapter from hardware to fit his shopvac output and then slide the paper filter over it. Many household vacuums are two inch holes like the pvc. Thought he had a great idea.

Rich Carlstedt
01-01-2009, 01:42 PM
Just get an old grease drum fellows and make your own seperator.
I have had a vacuum system in the shop for 27 years.
It makes shop time cleanup , a joy, compared to old days.
to keep from plugging the 2 1/2 " hose, when ever I use a table saw, I cut up
blocks the size of childrens play blocks . a little over 1 x 1 x 1 .
If you think you are getting blockage in the hose, let a few of these rip through . They clean the hose out as they tumble through it !

http://i273.photobucket.com/albums/jj220/StationarySteam/Shop%20Tools/ShopVacuumContainer.jpg

http://i273.photobucket.com/albums/jj220/StationarySteam/Shop%20Tools/ShopVacuumContainer2.jpg

The Sears ($25) Vacuum is outside (stays clean) and the suction line is located under the floor. it comes up in the middle of the shop where the barrel is located ( see the white pipe !)
The barrel has a copper pipe soldered at a tangential angle for vortec action. My shop hoses attach here.
The suction pipe is mounted in the cover with a large coffee can inside used to deflect heavy particles outward.
The "Flag" in the barrel bottom is just a weight to slow down the chips and add drag to airflow.
Before I built this shop, My earlier unit had the suction pipe come in at ceiling level, and run to the center, and then directly down to the barrel. That works OK too, but my floor mount means only 16 feet of run versus 32 before.

I only clean the shop vac outside twice a year, and it never has metal chips in it. The barrel needs a handtruck sometimes.
Last, whenever I have coolant or oil contamination, I have a pail of sawdust. A few hands full and the chips are stirred. then a few hours later it gets suck up.. Have used same hoses for 17 years, and no waxy buildup !.
this is proven in the picture, which was taken when the barrel was about 15 years old. the turbulance keeps it clean
Rich

PS
No glue is needed for any joints. they pull tighter together in operation.

pcarpenter
01-01-2009, 05:27 PM
The best improvement I have ever seen (and have posted about here before) are the Cleanstream filters for the shop vac and other brands. It resembles the traditional cartridge type pleated filters that come with the vaccuum, but uses a Gore (not Al, thank you) membrane that both stops more stuff and flows more air. I paid full price for my first one and then lucked out and found several more at a local Sears on closeout and now all three of mine wear them. Not only do they flow substantially more air, they are washable and therefore easier to keep clean. As already posted, keeping them from being full of crud is the key to good suction.

When I first put one on my large vac in my shop building, I found that I was sucking screwdrivers and other large items off the bench. It really flows a lot of air. They come with a rubber diverter that goes on the inlet inside the tank to keep stuff coming in from hitting the filter at high velocity and tearing it up. It makes a 90degree bend inside the tank which may also help with creating a vortex to allow heavy stuff to drop out.

I see folks use their "wet/dry" vacs with the filter in place while picking up wet or partially wet stuff....bad move. All it takes is a bit of dampness with the powdery dust in the filter to turn it into plaster....a great way to then burn up the motor. I would think that use of this around coolant would be the same....it could really plug the filter up quickly.

Paul

dp
01-03-2009, 10:42 PM
This seems to work quite well

http://www.cgallery.com/jpthien/cy.htm

Regards Ian

I've just finished building my version and it works great! I like my smaller vac for using on the machinery because it's easier to poke into the small spots. What I don't like is the small cannister and frequent need to clean out the filter. The Thien lid does a fantastic job of separating the crud into the lower can, and the added height makes it ideal for the bench.

http://thevirtualbarandgrill.com/machinery/ThienLid/

BillH
01-04-2009, 12:10 AM
I need to make one of those

dp
01-04-2009, 01:00 AM
I need to make one of those
It was a 1/2 day project using stuff on hand - just the kind I like. One thing I really liked about this is that even though I cut a hole in the bottom of that vacuum, the red cannister fits tightly into an orange Home Depot bucket, so if I need to use it again without the Thien lid I just drop it into the bucket and it's back to work.

danlb
01-04-2009, 03:02 AM
"The best improvement I've ever seen was to add a flexible smooth vinyl hose"

Is this just plain, unreinforced tubing? I thought it would need something to prevent collapsing.


The hose is for a 2 gallon Craftsman brand wet/dry shop vac.

The tubing is 1.25 inch od, 5/32 thick walls. The tube does not stay totally round, it's cross section becomes oval when it bends. The walls are thick enough and springy enough that it will not collapse completely. Since vacuuming swarf is a matter of airflow and not suction, the hose does not collapse in use from suction.

I forgot to mention that the tubing is clear, so you can see any buildup, clogs or even the screwdriver that you laid down in the drip pan without thinking.

Dan

dp
01-04-2009, 03:16 AM
I forgot to mention that the tubing is clear, so you can see any buildup, clogs or even the screwdriver that you laid down in the drip pan without thinking.

I saw some of that at Home Depot - it doesn't flex well. Rockler has spiral flex tubing that collapses nicely and expands to 10'. I couldn't find any 2", though, and that's what I'd like to continue using. Vacuum shops have long lengths of wall-attachment hose that may be an alternative. I like the transparency idea.

JoeFin
01-04-2009, 08:32 AM
The reason I said "Shop Vacs" lack the Hp. to make a good show of it was based on the shop my kid learned G-code in. They had a dedicated "Central Vac System" for all the machines.

Check out the "G 23" in this .pdf
http://www.heritagevac.com/downloads/ModernDay.pdf

26 Amps with 137" of water lift is night and day difference from the typical "Shop Vac"

They also used a "Smooth Walled PVC" to pipe the vacume through the walls and leave the noisy motorised unit away in a utility closet. The outlet by each machine turned on the vacume when you plugged the hose in, so they only needed 1 vacume to service many machines. They also had an ingenious fixture to keep the suction by the utting tool.

The pipe is very cheap - like I've been saying to all the guys building or adding on to their shop - "Don't forget to put in the pipe for vacume"

Rustybolt
01-04-2009, 11:23 AM
Thanks dp, I'm going to try that on our powdered nylon recovery vac.

Rustybolt
01-04-2009, 11:27 AM
If you're recovering a lot of powdery-dusty stuff there is a coil hose with a copper grounding wire already in it . Staic build up can give quite a painful shock.