Reversing an aquarium vacuum pump

[jeffthompson]

Hi everyone, I'm outfitting a frankenlathe and needed a vacuum pump. I want to remain portable, so instead of using a vacuum cleaner (which is noisy, bulky, etc) I bought an aquarium pump. But! I realized after it arrived that the pump was basically a compressor, pushing air out, not pulling like a vacuum.

I poked around inside the pump and was able to very easily reverse it. For $13 paired with some tubing and a jar, it seems like a pretty good bargain. Haven't fully tested it yet, but I'm hopeful this will work well.

IMG_8032.jpg

First, pry up the bellows mechanism with a small screwdriver. It is just friction fit.

IMG_8031.jpg

Then pull the white plastic part out, rotate 90º and re-insert. Be careful to re-seat the O-rings - they tend to want to jump their seating. Do this for both sides and you'll have a reversed pump!

[opcode66]

Let us know how the suction is. If it is consistent. And, most importantly, if it works!

[handcut]

Exciting times. I would be very keen to know if this works. My vacuum cleaner is in a very sorry state from overheating!

[jeffthompson]

Indeed! I'm now a little embarrassed to have posted so soon – I was excited that I could salvage this little pump. Need to go find some very thin tubing...

[rsimms3]

Old thread on the topic that may be of use:
http://www.lathetrolls.com/viewtopic.php?f=1&t=1778&hilit=aquarium+pump

[Soulbear]

Hi Jeff,
I read elsewhere on the forum about Aquatic Pumps being used for Vacuum. What I think would be really useful for both myself, and fellow Trolls developing their own Lathes, are Types/Manufacturers/Models/Details/Details/Details. I recently contacted a leading U.K. Manufacturer/Distributor of large Aquatic Pond Aerification pumps. I chatted and explained at great length about what I was trying to acheive with their pump, only to be told that their models had no facilities to attatch a pipe or construct an inlet port onto them. The inlets being some irregular shaped hole from an Air Cleaner Filter Box. This sort of detail was not apparent when looking at the on-line sales literature. I was looking to buy the largest Cubic/Foot/-Litre/Min Pump I could reasonably afford, my thinking being, that once Vacuum Clamping to the platter is achieved, the highest available flow rates would in all probability be the best for swarf/chip pick-up. At £100/$150 and upwards, its a fairly costly purchase, for a hack that may not work. My point is, who would want a Bloody Great Vaccum Cleaner blasting away, when there are more elegant and much quieter alternatives, if only we knew which models are the most effective and are best regarded. A BIG SHOUT OUT TO PRO TROLLS"WHAT SPECIFIC MODELS WOULD YOU RECOMMEND?" Many Thanks Soulbear

[Soulbear]

Hi There,
Just out of interest I thought this might be a suitable contender:-

Vacuum Pump.jpg

Specifications

Type piston compressor, oil free
Output 1/5 hp (150W)
Rotation speed 1450 / 1700 rpm
Standard volume 20 - 23 l/min
Max. pressure 4,0bar
Max. Vacuum 600mm Hg
Hose connection 1/8 inch (9,51 mm)
Cable length 1,8m
Nozzles suitable for all types of airbrush with nozzles 0,2 - 1,0mm
Dimensions 255 x 135 x 170mm
Weight 3,7kg (light and portable)
Noise ca. 40 dB (low noise level)
Overheat protection available
Has any Troll used this or similar with good results? Many Thanks Soulbear

[jeffthompson]

soulbear – I posted a link to the pump I bought, but it was kind of hidden Here's the link: http://www.amazon.com/gp/product/B0009YJ4NG?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00

Re reversing the pump, see the images above. There is not connection built into the pump, which is why I reversed the mechanism. Now what was the air in is air out, and what was air out (the small connectors for tubing) is air in.

If you want a bit more detailed explanation, I posted a short tutorial: http://www.jeffreythompson.org/blog/2015/08/10/reversing-an-aquarium-air-pump/

I'm going to get some tubing today and see how well it works. Fingers crossed!

[tragwag]

I tried this with this air pump: http://www.webbsonline.com/Item/Pondmaster-Air-Pumps-04580?gclid=CLn7-Nzoo8cCFQ2PHwodGn8B4Q
after a bunch of frustrating work, and mounting it in a subwoofer box, there wasn't enough suction through any tubing/chip jar combo I fashioned up.
I went back to the vacuum cleaner setup, and things are smooth.

[jeffthompson]

Quick update: I got some tubing that fits and plugged everything in. The vacuum seems pretty good! Mine has two inlets (formerly outlets) and so I hooked them together for maximum suction. I don't have small enough fittings to hook up to a jar yet, but I did suck up a few little pieces of wood and they just shot up into the tube (which is uncut and about 5' at this point).

Not sure how it will do on the lathe, but this looks really promising. I'm cutting plastic for the moment, so the swarf is really thin and lightweight.

Here's the way I have it hooked up currently:

IMG_8040.jpg

[jeffthompson]

Suction! I finally got some tubing and fittings that works with the pump (3/16" ID). It's no vacuum cleaner, but it has plenty of suction to pull up sawdust and fine plastic swarf into the jar (a plastic one from the Container Store with an O-ring in the lid). I'll have to test it on the lathe proper, but for a very compact, cheap, and quiet solution, I think this might be a good starting point.

IMG_8059.jpg

[dimi751]

Hi jeff

Great job on the diy vac system, good test will be with swarf material, but I don't think there will be suction problems, you probably already
Done this, did you put a small hole in the container
So it does not implode ?

Keep us updated this is a interesting topic

Thanks for sharing this !

Best
Dimi

[jeffthompson]

Thanks dimi751. I didn't know about the small hole – what diameter should it be? Is there a good spot for it to go?

[dimi751]

Good point Jeff

Usually the standard vacuum hose fitting has a plastic slider and you can adjust the suction power from there

I would put a small breather hole on top on the containers lid Around 5mm diameter.

Try without the hole first, if the food container starts
To implode during suction ( this will depend on the vacuum suction power then drill the hole. Otherwise don't worry about the hole.

[cosmO_O]

Thanks Jeff for the post!

I bought today an APS 400 (liters) type pump, after 5 minutes of assembly its made a really pretty vacuum. So i can confirm, the method is working. One thing, because its not a vacuum cleaner, every cm tube is matters, so watch the length

[dimi751]

Hi jeff

Any progress ? Interested to hear if all worked well

[jeffthompson]

I have it all hooked up, but am finishing up a bracket to attach the hose to my lathe. Hoping to do some cutting in the next day or two.

@Hole in the jar:
I'm going to forgo for now and take my chances 5mm is about almost 1/4" – that's pretty big, no? I was thinking more of a pinhole size. I would worry a hole that big would cause the system to lose suction.

@Length of hose:
Yes, definitely longer runs = less suction. I ran mine on 5' (1.5m) and it worked fine. The nice thing about a very quiet vacuum: it can be really close by!

[dimi751]

Hi jeff

Thanks for the update !

Sounds promising so far, where is the pump located when you cut the record ?

Dimi

[jeffthompson]

Update: it works great!

The overall setup of my vacuum. Might be a good idea to move the vacuum a bit so it doesn't vibrate the table, but works for testing.

IMG_8073.jpg

Closeup of the vacuum and container with tubing attached. I'm replacing the small T intersection with a Y fitting, which is better for airflow (sharper corners = less flow).

IMG_8074.jpg

The aluminum bracket holding the tubing in place. This is just a small piece of flat bar epoxied to a piece of 3/16" OD aluminum tubing. It swivels a bit, so I can adjust the placement of the tube.

IMG_8075.jpg

I spliced in an inline switch to the vacuum so I could turn it on and off without having to unplug it.

IMG_8078.jpg

Any thoughts or suggestions for improvement most welcome!

[rsimms3]

Looks good! My one question/concern would be the hose resting on the turning platter. All the other vacuum setups I've seen have the tubing attached to the carriage so it moves with the head and keeps it from rubbing on the platter or getting accidentally tangled in something else. Otherwise this looks like a good approach. Vacuum apparatus is fast approaching as my next project if I can get my signal chain down pat for plastic impressing.

Also, and others will probably know, are there disadvantages to using the plastic tubing from the head to the catch container vs using the yellowish surgical tubing?