Need Ideas For Bench Grinder Table Vacuum System

[nc5a]

Except for the doors and the vacuum hose/nozzle that reaches each grinding station the table is done. But the vacuum hose/nozzle is causing me problems.

I'm looking for a flexible 1 1/2" to 2" OD smooth bore hose that stays put where ever I bend it to. My plan is to use one flexible vacuum hose and bend it where necessary to reach each of the 6 grinding stations. So when I adjust it to suck up the grinding dust I want it to stay where I put it.

What kind of hose would that be and what search words would one use to find it? Vacuum hose would work although it's not smooth on the inside but it would work. But the problem is making it stay where I put it. I really don't want a bunch of clamps or brackets hanging all over the place to hold the hose. Probably 20-24 inches of hose will get me to all the stations. The 2" diameter hole in the center of the table is the vacuum source port.

Any Ideas?

Ron

[Tundra Twin Track]

Flexible steel exhaust tubing should work, but mount tubing so grit does not plug up spiral joints.

[alanganes]

Maybe attach the hose to a section of goose neck like the sort used to hold lamps and microphones. If you anchor it in the center of the table by your vacuum inlet, it could reach around to any of you grinders.

Nicely done setup, by the way.

[JoeLee]

Flexible steel exhaust tubing should work, but mount tubing so grit does not plug up spiral joints.

How would you do that??
Grit is going to collect on the inside walls of the piping no matter how you mount it.

JL...............

[JoeLee]

This is what I rigged for my SG and my T&C grinder if it's any help.

If I have to do any heavy grinding with my bench grinder I take it out side.





JL...........

[Mcgyver]

As we do exhaust and dust collectors occasionally, the starting point is what sort of CFM each pick up point needs. I believe there are tables of suggested values for small machines, 500 CFM comes to mind for a grinder. Maybe its less, can't remember but its likely a lot more than a vacuum can deliver. It would be worth looking at, you might need a more powerful blower to get the results you want.

[Tundra Twin Track]

How would you do that??
Grit is going to collect on the inside walls of the piping no matter how you mount it.

JL...............

The way the flex pipe is crimped when manufactured the flow of product should only travel one direction so not forcing product into the seams.On a grain vac if you have it the wrong way the Vac really jerks as the flow of product cavitates.

[BCRider]

What about individual collection funnels for each wheel that you plug the regular hose onto? Each of the grinders you show will have it's own unique pattern of where the majority of the swarf flies. And that pretty much means a different shape of collection funnel to catch and work with the energy of the swarf so it works for you. And that pretty well means different funnel designs for each wheel. And if that's the case you simply connect the regular plastic hose that comes with the vacuums to each collector funnel which is mounted to each grinder.

I'm getting some deja vu here.... Was it a thread of yours about this same topic where I mentioned the same idea of separate collection funnels?

[ahidley]

How about a four way valve? Plumb them all through a 4 way manifold and have a valve to only allow one to suck at a time and have it set up like the above post..

[Paul Alciatore]

The swami SEES all.

The swami SEES a vertical pipe (3" PVC?) in the center The swami sees a smaller vertical pipe (2.5"?) that slides in that pipe, held by a thumb screw and with some packing to hold the vacuum.

The swami SEES an elbow on the smaller vertical pipe bringing it horizontal.

The swami SEES an even smaller horizontal pipe in that pipe, again with thumb screw and packing.

The swami SEES a second elbow to bring the third pipe down toward the grinding stations.

The swami SEES another, even smaller pipe in the downward pipe. This, final pipe is once again held with with thumb screw and packing. It can extend to each grinding area. It has an elbow that can face the wheel to catch the dust.

That should give you complete adjustablity in all three dimensions and the ability to aim the suction port directly at any of the wheels, at any height, and at any angle.

At that final position, you could use an elbow that adopts to a larger pipe size to increase the area of the suction port. You will need to drill and tap the PVC pipe for the thumb screws: If you use thinner gauge pipe you could add half of a splice fitting on the ends to increase the thickness to allow more threads there. That half splice could also be made to hold the packing/gasket that seals against leaks.



With this design, the walls are smooth and the transitions are always from smaller to larger so the accumulation of grit inside the pipe should be minimal. Another idea just hit me: add a long, vertical spring on that first vertical adjustment to hold most of the weight of the assembly. That would make adjustment easier. That would work better for me than you as you need a full 360 degree rotation there.

PVC pipe fittings will have a friction fit. That means that you could have different collecting funnels for each station. They would fit into the final elbow.

I like this idea - yea, I know it's mine so I should. But I am planning a multiple grinder station, probably on a rotating table and I had some other ideas in mind. They involved multiple air gates and would be somewhat involved and perhaps more expensive. But this looks better so I may very well use it myself. One advantage for my grinder station would be that my table could rotate around the largest, vertical pipe so the vacuum stays still under it. But that will not be today or even this month or next. I have too many unfinished projects as it is.

[Paul Alciatore]

Another idea just hit me: Using my idea above, attach one or two of those small, LED, goose-neck lights to the horizontal arm, near the second elbow. They should provide excellent illumination for your/my work.

It just gets better and better. "I love it when a plan comes together."

[nc5a]

What about individual collection funnels for each wheel that you plug the regular hose onto? Each of the grinders you show will have it's own unique pattern of where the majority of the swarf flies. And that pretty much means a different shape of collection funnel to catch and work with the energy of the swarf so it works for you. And that pretty well means different funnel designs for each wheel. And if that's the case you simply connect the regular plastic hose that comes with the vacuums to each collector funnel which is mounted to each grinder.

I'm getting some deja vu here.... Was it a thread of yours about this same topic where I mentioned the same idea of separate collection funnels?

BCrider.....I think I remember you posting a comment about vacuum/dust collection arrangements but I don't remember if it was directed toward me. But I get the drift about different shaped collection chutes. I'm trying to make this simple so I use it every time I grind. Recognizing of course that it probably won't be very efficient. Designing and building collection chutes for the 6 grinding stations isn't something I have time for right now.

When I get my surface grinder up and running it will require more careful consideration for a collection chute.

[nc5a]

The swami SEES all.

The swami SEES a vertical pipe (3" PVC?) in the center The swami sees a smaller vertical pipe (2.5"?) that slides in that pipe, held by a thumb screw and with some packing to hold the vacuum.

The swami SEES an elbow on the smaller vertical pipe bringing it horizontal.

The swami SEES an even smaller horizontal pipe in that pipe, again with thumb screw and packing.

The swami SEES a second elbow to bring the third pipe down toward the grinding stations.

The swami SEES another, even smaller pipe in the downward pipe. This, final pipe is once again held with with thumb screw and packing. It can extend to each grinding area. It has an elbow that can face the wheel to catch the dust.

That should give you complete adjustablity in all three dimensions and the ability to aim the suction port directly at any of the wheels, at any height, and at any angle.

At that final position, you could use an elbow that adopts to a larger pipe size to increase the area of the suction port. You will need to drill and tap the PVC pipe for the thumb screws: If you use thinner gauge pipe you could add half of a splice fitting on the ends to increase the thickness to allow more threads there. That half splice could also be made to hold the packing/gasket that seals against leaks.



With this design, the walls are smooth and the transitions are always from smaller to larger so the accumulation of grit inside the pipe should be minimal. Another idea just hit me: add a long, vertical spring on that first vertical adjustment to hold most of the weight of the assembly. That would make adjustment easier. That would work better for me than you as you need a full 360 degree rotation there.

PVC pipe fittings will have a friction fit. That means that you could have different collecting funnels for each station. They would fit into the final elbow.

I like this idea - yea, I know it's mine so I should. But I am planning a multiple grinder station, probably on a rotating table and I had some other ideas in mind. They involved multiple air gates and would be somewhat involved and perhaps more expensive. But this looks better so I may very well use it myself. One advantage for my grinder station would be that my table could rotate around the largest, vertical pipe so the vacuum stays still under it. But that will not be today or even this month or next. I have too many unfinished projects as it is.

Paul.....I had a brother that was given away at birth, could you be him? We have exactly the same idea except mine is constructed with 1 1/2" plumbing fittings like used under a kitchen sink. The flexible joints would be possible with the nuts and cone seals lightly snugged up and the nut locked in place with a tab. This was my plan until I discovered this, https://flexpvc.com/cart/agora.cgi?p...-025-2-1/2inch. I think it's made to order and self supporting to 36". A bit bigger than I need but it's already anti static and built for vacuum systems. Nice drawing by the way.

Ron

[Tom S]

I'd be worried about the suction loss you would see with all the bends and reductions in that design. The reduction in pipe size as you move away from the might be sufficient to keep a higher level of vacuum, but at the cost of a reduction in the volume of air being pulled in by the vacuum. Think of it as the reverse of a pressurized tube, reducing your diameter over distance will keep the pressure up, but will also result in a reduction of cfm. And like Mcgyver mention, you need a certain amount of cfm to have a sufficient dust removal system.

I'd go with BCRider's recommendation of a variety of different collection funnels permanently mounted to the machines, with a smooth-bore vacuum rated tube that can be switched from funnel to funnel. Keep the bend radius of the tub large when accounting for the different funnels to help keep the suction level where it needs to be.

[Paul Alciatore]

That stuff looks neat but the price seems a bit steep. 24"= $60 and 36" = $90. I haven't priced it yet, but the PVC or drain pipe ideas may be a lot less expensive. Re: PVC vs. drain pipe, I think the PVC with thumb screws would be easier to adjust but the drain pipe would probably have better seals.

I don't think going to a larger pipe/tube size and then back down to a size close to the original vacuum hose would have a large effect on the suction. And the larger size would make the effect of the elbows somewhat less. After all, PVC pipe is used for central vacuum systems; the 2" size I think.

On that brother thing, I don't know. But my mother says they found me floating around in the flood when the levee broke after a hurricane. Thank goodness that basket was waterproof.

Paul.....I had a brother that was given away at birth, could you be him? We have exactly the same idea except mine is constructed with 1 1/2" plumbing fittings like used under a kitchen sink. The flexible joints would be possible with the nuts and cone seals lightly snugged up and the nut locked in place with a tab. This was my plan until I discovered this, https://flexpvc.com/cart/agora.cgi?p...-025-2-1/2inch. I think it's made to order and self supporting to 36". A bit bigger than I need but it's already anti static and built for vacuum systems. Nice drawing by the way.

Ron