Dust/debris in my vacuum pump lines 2

[dogboy74]

Hi-

Apologies if this is in the wrong sub. I have a little vacuum pump system I use for to vacuum-form plastic over plaster models. My problem is that after a while tiny bits of plaster from the models gets pulled into the system and clogs it up. I just tore everything apart and cleared it out for the second time in the last year and would like to prevent future clogs.

The air comes in from my workbench and down the braided tube into the system. Would it be possible to add one of these air filters pictured below in the very beginning of the system to catch the fine plaster dust and sand size particles? If so would it have to be laying flat so the little bottle is on the bottom or could it sit vertically? If not, could I do a high loop type of thing where before the braided line comes down the back of my workbench into the system it goes up 2 feet or so and then back down to try and trap that debris in the bottom of the loop? I have the vacuum set to turn off when it hits 10 mmHg.

Any help would be appreciated. Thx

 

[Doug Hunter]

To filter fine plaster dust, I think you'll need a filter with a paper element. That metal mesh probably won't catch it. It would be helpful to understand your smallest particle size to be filtered, and then you can buy a filter that is rated for it.

Best regards,
Doug Hunter
Altarium Technical Consulting

https://www.altarium.us/

 

[3DDave]

If you put the filter there then the flow will be restricted when you want to pull the plastic.

Put it after the holding tanks; I agree with the paper filter. The larger the housing the better to give the dust more time to settle.

 

[3DDave]

Another thought - have you tried a spray coat of shellac over the plaster to capture the plaster? It dries fast and is very thin.

 

[Artisi]

Agree with 3DDave, probably more effective to seal the plaster models.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[LittleInch]

Like the others say, first figure out what size dust or plaster and sand particles you want to capture, then choose your filter medium accordingly/

Some sort of paper or fibre would be the best, but also have the biggest pressure drop so pumping down your mold would take a bit longer.

If that little one is fine then I can't see why vertical wouldn't work, just emptying it would be more difficult as the bits would fall out before you unscrew it. check which way the flow path goes, most go out to in.

A loop won't work unless you make the bottom loop bit about 10 x bigger than the main hose.

An alternative is simply a large pot with entry in on side and exit the other with a small mesh filter which then drops all the big bits into the bottom of the pot. but a proper filter is best and reduces the volume of the air to be sucked out.



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Also: If you get a response it's polite to respond to it.

 

[dogboy74]

Thanks for all the ideas. There is definitely plaster dust size particles along with sand size and maybe slightly larger but fine dust would be a factor. The shellac is a pretty novel idea and I think would help at least reduce a large portion of this.

 

[dogboy74]

Does anyone know how the filter in the pic above I provided works? Does the air intake get forced down into the mesh strainer through bend in the tube inside is it just straight across and uses gravity to trap whatever comes in as it falls down?

 

[LittleInch]

My guess is that one nozzle ( inlet) feeds the external bowl and then the air flows through the mesh into the centre which then feeds the other nozzle. Then bigger bits and dirt when no flow falls into the plastic bowl.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[3DDave]

Yup - outside in so the collection of material is visible and the gas velocity is a little lower to let the big chunks drop out.

 

[Artisi]

Look at cyclone dust extracter.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)

 

[pierreick]

Hi,

https://powertecproducts.com/blog/cyclone-2stage-dust-collectors/

May work for your application(principle), similar to cyclone.
Pierre

 

[LittleInch]

Guys, this is a minute little domestic vacuum mold set up here, not a mass air flow dust extraction system....

Let's not go berserk here.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[dogboy74]

Yea, it's just a little vacuum system and I don't see how I could put that giant dust thingy in the line. I put it back together today so I could get back on with my work but I need to get a filter in there sometime soon. It's a major pain taking it apart and getting it back together sucks just because the design.


In the meantime I'm going to try shellac and put extra care into just keeping the plaster out of the system as much as possible.

 

[Artisi]

There is no need for a "giant dust thingy" do an internet search and you might be surprised what you turn up.
"small dust cyclone" might help.

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)