12V Vacuum Pump Arrived

A nifty red box showed up which contained a 12V Vacuum Pump I ordered from Spark (first thing I ever ordered from there).

I will use it for a pick and place. Perhaps a small vacuum clamp. Should get to that in about 20 years or so.

Vacuum

vacuum

Just picked up this vacuum pump at sparkfun.

I’m planning on doing some experiments with pick and place and perhaps vacuum holdown for small parts on CNC systems.

CNC vacuum foot

skirt

Okay so I went to do my first job with my new CNC vacuum system. I discovered that I made the vacuum foot too deep. It sort of competes for space with the workpiece hold down clamps.

So I made another. It just took a few minutes to modify the design to make the foot shorter and thinner. I also made the floor counter sunk into the bottom. This is something I really like about computer aided design and manufacturing. You can repeat things with less effort.

It cut out in about 20m at 6600 rpm at 90ipm with an 1/8 inch 2-flute endmill. It took about 5m to cut off flash and another 10m or so to clamp the pieces and throw some Methylene Chloride at it to “weld” it.

The new vacuum head is much smaller. It’s so cute!

insert

With the foot higher relative to the endmill, I’ll need a longer skirt to help prevent material from flying out and to accelerate the vacuum.

So I made this insert which would help to mount the rubber skirt underneath the foot. When I cut the insert out, I used the vacuum shoe even though it still lacked the rubber brush/skirt. As you can see in the video, the pieces fly away with too high a velocity for the vacuum to grab them.

It was a little tricky to mount the rubber skirt onto the shoe. I eventually wrapped the skirt around the insert, wet the outer surface of the rubber then stuffed it into the shoe. I used a small screwdriver to get it to fit. After it sat for a while it seemed a pretty good friction fit.

sexy!

It worked out well.

I then split the rubber skirt with a pair of scissors.

I think it’s a bit long. It dips below the end mill when it contacts the work piece.

In retrospect, it should probably not contact the workpiece till the endmill is plunged into the workpiece.

Once I had it mounted, I decided to give it a try. I used it to cut out a bracket to hold the other end of the vacuum hose to the table top.

I added that to the video as well so you can see the effect of the vacuum. I had the vacuum off and on.

It works really well, I’m really happy with the outcome.

One small issue is that the skirt is a bit long and touches the endmill sometimes. I think I will shorten it till it doesn’t do that.

I think if it got caught in the endmill it would make a big mess of everything.

it works

If the skirt misbehaves after that I’ll make another shoe that is wider so it can be further from the endmill.

Sounds like a lot of work but making another iteration takes very little time.

I guess I’ll share the CAD and g-code files if anybody is interested.

Obviously it will work for anybody that has a spindle based on one of those servo motors like I have.

Aside from the skirt brushing the endmill a bit, it’s working perfectly.

Next I will mount run an exhaust hose from the vacuum to the window so that the dust and chemicals that get sucked up are vented outside.

table clamp

I guess I need to get a shop vac with a proper exhaust hose.

The one I have just vents into the room. Not so great if you’re picking up dust because some will always go straight through.

One thing I really like about using the rubber skirt is that there is really good visibility of the cutting and the workpiece.

I think it’s fairly important because you can spot problems before they happen sometimes.

One thing I’m not happy with is that my shop vac is really noisy. It’s about twice as much noise as the mill itself.

It’s going to take some work to solve that problem. Perhaps a quieter vacuum. Perhaps a workbench with a vacuum enclosure. Perhaps I can put the vacuum in a different room.

Dust Skirt for CNC

cnc dust collector

I just drew up a design that I think will work. It will be a box that has has a hole which will fit onto the spindle motor shoulder.

That’s the larger hole which will be on the top of the box. The top of the box also has another hold to attach the vacuum.

The floor of the box will have a hole for the spindle to exit.

The little circles are to make the tube to attach the vacuum.

I’ll cut this out of acrylic and then glue it all together.

I’m debating if I should go 1/8th or 1/4 thickness.

tube

1h Later: Okay, I cut it out of a piece of 1/4 extruded acrylic.

It came out quite nice. The hole I cut for the top of the box fits my mill spindle perfectly.

I have Methylene Chloride which is great for gluing acrylic.

As you can see the little rings form a vacuum hose mount.

Because the surface of the acrylic is so smooth, you can’t even tell that the hose mount is several pieces.

skirt

After glue drying: Here is is installed.

It has a really good friction fit but I know that will become an issue since it will be taken off and on the machine every time a different endmill is mounted.

Also, I cut the lower hole too small so I will make another bottom plate. Actually, it’s tempting to just skirt the whole thing.

I can see that it will increase the chance of collision with clamps for holding material. If I break this one and need to make a new one, I will make it tapered so that the side with the vacuum hose is higher up.

Roomba

roomba

Dust is sort of an issue when you have a CNC. I got a Roomba that is in need of repairs. I understand it needs a docking station, battery and there is an infrared or led burned out somewhere.

Hopefully I can get it working and it will put around and gobble up any stray particles and dust.

Dust Control on CNC router/mill

dustcontrol

I’m working on a solution for grabbing dust while cutting. Here’s a design I just came across.

I think something like this made from clear plastic and a clear plastic skirt would be pretty cool.

The difference I would add is to channel the wood so that the suction appears around the end mill. Then the skirt could come down from there to stop debris from flying out and increase the suction.

Challenge: Where to get some nice vacuum hose? I tried Prices Auto in Ottawa so far and nothing close.