Shop Vac Question

[CFLBob]

The inescapable cleanup from the milling machine either ends up in the shop vac bag, in the case of steel chips, but I sweep aluminum chips up with a small dust pan and save them in bucket, believing that someday I'll melt them down and cast aluminum.

Monday, while I was sweeping up a few cubic inches of aluminum from the latest piece, I thought of a dust separator like the ones woodworkers use. Supposedly, these work by swirling the air in the separator between the nozzle and vacuum cleaner itself. While swirling around, the heavier chips fall into the bucket while the lighter dust goes into the shop vac.

Almost as if they read my mind, Rockler sent me an email today showing their separator is on sale. It looks like this, for those who don't recognize the term separator.



It seems like if it works for wood shavings it should separate metal chips pretty easily, but has anybody tried this?

It seems like the idea would be good. Maybe not this exact one, but the concept seems easier than swapping the bags in my shop vac.

 

[GreenTwin]

I purchased on, and they do work well, but are rather a pain since they take up the space of a 5-gallon bucket next to the shop vac.
I forget exactly which brand I purchased, but there is a video online where a guy tests all of them, and finds the one that supposedly works best, which is the one I bought.

If I had a shop dust collection/chip collection system, I would definitely use a wall-mounted separator, but I have not had time to make a dust collection system yet. I have resorted to just changing shop vac bags for now.

They do work though, expecially the one I bought, and will even separate fine dust.

I bought the Dust Deputy. Seems like I made a plywood disk to mount on top of a 5 gallon bucket lid, to make the lid a little more rigid.

 

[Scott_M]

+1 on the dust deputy. Although I use it before my dust collector on my sandblast cabinet. 5 gal bucket gets full maybe a cup gets by and into the dust collector, The bucket is much easier to dump.

Scott

 

[abby]

Melting aluminium turnings/chips will be a waste of time , the very large surface area results in heavy losses due to oxidation . If you want to do some casting you can find cast aluminium engine parts quite easily.
Dan.

 

[GreenTwin]

Melting aluminium turnings/chips will be a waste of time , the very large surface area results in heavy losses due to oxidation . If you want to do some casting you can find cast aluminium engine parts quite easily.
Dan.

This is very good advice.
I would not recommend trying to reuse metal chips, or aluminum cans.
Aluminum cans are not necessarily the right allow for engines.
For generic/art work, maybe chips or cans, but even then I would not recommend chips.

I use 356 alloy aluminum, which is generally what is used when casting aluminum.
I use gray iron scrap from large motor end bells for casting iron parts, and it seems to work well.

The brass/bronze folks mention how easy Evadur is to use, in lieu of straight brass.
I have melted straight brass, but the zinc will burn off, and you must avoid all of the zinc fumes.
I don't do brass/bronze anymore, just because of how difficult it is to melt/pour, and control the fumes.
I have not tried Evadur though.
I am not sure if Evadur is the appropriate alloy for things like engine bearings and such.
I would think engine bearings would need to be bronze (I plan to use babbitt).

.

 

[rklopp]

Why not a shop-vac without a bag? I have an old 5-hp Rigid that sucks chips of all kinds just fine. I do not try to separate the aluminum from the ferrous or the cat hairs. When it's full, I take the head off, dump the bucketful in the trash, and blow off the filter. The only problem is that oils slowly plasticize the hose and it kinks more easily. I am on my second or third hose, the the vac itself is probably 15 years old.

 

[CFLBob]

Abby and GreenTwin - thanks for that well thought-out advice. I know that creation of aluminum alloys includes the thermal treatment it gets as being made. This doesn't have any soda cans in it, but I'm sure it's not all 6061. There's some 2000 series in there for sure, and other things I don't know about. Corners of a window screen frame I rebuilt. Junk.

I should probably just see if one of the scrap dealers will buy a few pounds of aluminum scrap (been collecting it for years).

This Ridgid vacuum is a few years old and I've always had a bag in it. Aluminum, steel, brass, cat fur, long-dead or freshly-dead lizards, leaves, whatever. It all ends up in it.

 

[kwoodhands]

I used to mill lumber and made a separator. Plywood box on wheels. 3" PVC toilet floor flange adaptors for the inlet and outlet hoses. 4" hose fits perfectly on these adaptors and a hose clamp .
I have not used a separator for metal, I do not get dust, just swarf.
When the separator was full of chips I pulled the box outside and dumped the chips into a mulch pile.
I sold the composted mulch for $10.00 a pickup load. Just happy to see the pile go down.

 

[ChazzC]

Home Depot has their own version (Duststopper for $40), much cheaper than the Oneida. Other than occasional hose plugs from aluminum rats nests, this has worked well for me. I still have a filter in the Shop Vac (SS14-550, 8 Gal 5.5 Hp from Costco on sale a few years ago), but just as insurance against fine dust when using the setup to cleanup after a wood working project. I put mine on the bottom shelf of a cart with the Vac so I could tuck it away in a corner near the lathe & Mill, but still move it around if needed elsewhere (I did have to take the Caster Dolly Ring off of the Shop Vac to make it fit, which was a pain):

I also added a Rigid Diffuser ($13.50 @ HD) to the exhaust port on the Vac to stop the blowing:

At first I put the Duststopper on a "Homer" Bucket and had a 4' 2-1/2" hose connected to a 7' 1-1/4" hose; this setup collapsed the bucket after a year+ of use. So I replaced the hoses with a 1-7/8" hose from Lowes, which reduces pressure in the system, easily reaches all of my metal working tools/areas and also seems to have eliminated rats nests clogs:

The hose fits the connection on the Duststopper and includes a 1-1/4" adapter so I can use "regular" attachments. I did get a 1-7/8" crevice tool when I picked up the hose for general cleanup:

I replaced the plastic bucket with a heavy duty, epoxy coated one from Grainger ($26):

I have not had any issues with hot chips, but I don't generate them in large volumes and the shop vac pulls a lot of air (195 CFM).

 

[Richard Carlstedt]

I put a 2 " PVC pipe under the shop floor before it was poured and the ground level
behind the shop is about 4 feet lower and I placed the vac outside under a small shed.
Inside , I have a 20 gallon drum with a "vortex" coffee can set up. All ho,e made and works perfectly.
The drum gets all the chips and dust and very little ever reaches the vac. I clean them both every 6 months. I soldered a piece of 2" copper drain pipe tangentially to the top of the drum. A large coffee can with both ends removed was mounted to the cover. The chips and air come in and fly around the inside of the drum, so I added a "Flag" at the bottom ( just a weight really) to slow the spinning chips and they settled down to the bottom. The air being light and free of particlesgoes to the coffee can center and out to the vac. The PVC fittings are NOT glued and all may be disassembled. Outside the vac is protected from weather and has a remote electronic Start/Stop control has been working for 30 years with the same Sears 5 gallon shop vac.
Rich

 

[awake]

I made my own wood-dust/chip separator out of a 30-gallon metal trashcan, plywood and window seal foam for the lid, and plumbing fittings to suit the 4" hoses on the woodworking dust collector. It works quite well. I don't see why a similar arrangement suited to the size of a shopvac wouldn't work well with metal chips ...

 

[CFLBob]

Lots of good ideas here, especially @ChazzC and @Richard Carlstedt. Of those two, @ChazzC's is better for my place.

But I'm seriously thinking back to @abby saying not to try to melt down chips and cast them.

 

[Mike Henry]

I use the Oneida Dust Deputy and have been happy with it for the most part. It does a great job of keeping debris from the shop vac but the Dust Deputy itself tends to fall over if you pull the hose far enough to take out the slack. I like ChazzC's approach to that problem and will probably implement it.

The other issue is the hose tends to get stiff with use, maybe from cutting oils or fluids, and needs replacing periodically. I tried some 2-1/2" reinforced hose from Rockler and wasn't happy with it. That was replaced with reinforced hose from Oneida and I'm much happier with that.