Nomad 883 Pro Dust Head

[mbellon (Mark Bellon)]

There have been a number of dust heads for the Nomad - @Flatballer, @patofoto - each with its own set of advantages and disadvantages. I’ve decided to enter the ring with a dust head for the Nomad 883 Pro.

The Nomad 883 Pro is a challenge for a dust head since one of the changes made (from the Nomad 883) was to dramatically reduce the distance from the gantry to the edge of the spindle. Due to the design of the Nomad 883 Pro there is only 0.100" of usable space behind the spindle. In reality, it is even less since margin must be calculated in. My design has only 0.050" behind the spindle… and still barely clears the gantry when it is moved downward.

Because no brush can go behind the spindle and clamping the spindle using a split ring design doesn’t have much material to work with, I’ve elected to use two brackets. The brackets attach to the top plate and use a flexible pipe clamp to affix the brackets to the spindle.

The brush plate is affixed to the top plate via magnets.

Yes, that means there is no brush “behind”. The current design is quite good at controlling the “mess” but I will modify this discussion once I come up with a fourth piece - a brush which is fixed to the bottom of the gantry.

The brush plate has the standard brush mounted such that the brush cannot come in contact with the spindle - no brush eating!

Let’s get started!

PARTS YOU WILL NEED

2 - pieces of Starboard - 2.5” x 2.5” x 1”

I got these from TAP plastics. I live near one of their stores so I just stopped in and had them
cut the pieces from 1.5” thick stock to order. Their cut to order service is also available via
their WEB site.

2 - pieces of Starboard - 5.5” x 6.25” x 0.5”

I got these from TAP plastics. I live near one of their stores so I just stopped in and had them
cut the pieces from 0.5” thick stock to order. Their cut to order service is also available via
their WEB site.

4 - Neodymium magnet - 0.75” in diameter, 0.187” thick, 10 pound pull

I got these from McMaster-Carr (MMC), part number 5862K973.

WARNING! These are *VERY STRONG* and can be a real bugger to get apart. Be careful!

1 - piece of tubing - 1.5” diameter, 5 feet long.

I got this from MMC, part number 5500K31.

2 - tube fitting

I got these from MMC, part number 5500K17.

1- easy cut brush - 2 inch brush, 3 foot length

I got this from MMC, part number 7900T5.

1 - flexible pipe clamp - 0.5” tall, ~1.75” diameter when fully expanded

I got this at my local hardware store.

4 - #8 construction screws - 0.75" long

I got these at my local hardware store.

4 - #8 washers

I got these at my local hardware store.

NECESSARY TOOLS

0.125" square end end mill
Phillips screw driver (for screws)
Pliers or vise grips (for the press fit of the magnets)
Dremel or cutting tool (for the construction tabs)
Dremel abrasive disk or sand paper (to remove the construction tabs)

MACHINING PARAMETERS

ALL OF THE PARAMETERS IN THIS POST ARE DONE AT 10K RPM!

ALL PARTS HAVE THEIR STOCK CREATED BY ADDING 0.25" ALL AROUND IN X AND Y.

ALL CONSTRUCTION TABS ARE 0.1" IN WIDTH AND HEIGHT.

SPINDLE BRACKET

Two of these will need to be machined.

TOP PLATE

PLEASE PAY CLOSE ATTENTION! THERE ARE INCLUSION AND EXCLUSION REGIONS!

BRUSH PLATE

PLEASE PAY CLOSE ATTENTION! THERE ARE INCLUSION AND EXCLUSION REGIONS!

CONSTRUCTION NOTES

Construction tabs can be cut/sanded/ground off. I used a Dremel with a diamond covered grinding wheel.

The brackets are 1.000" inches deep. To machine these using commonly available end mills - including those from C3D - the “stick out” (the distance from the bottom of the collect nut to the bottom of the end mill) must be adjusted. Commonly available end mills are 1.500" inches long. When placed in the collet and collet nut, the “stick out” must be adjusted so that it is slightly longer than 1.000". Failure to do so will result in a collision.

Notice the “machine whole stock”? This will remove all of the stock that is not geometry (the part).

The inclusion ensures that machining will affect everything inside (leaving the tabs). The exclusion for the corners of the top and bottom plates excludes stock that is a waste to machine… this saves a LOT of time.

Another reason things are done this way is to ensure that the large openings are machined away. This prevents anything from coming loose and potentially ruining the part and/or breaking an end mill.

The “press fit” for the magnets is a bit tough. I used a pair of vise grips. Remember that these are very strong magnets, so be careful!

I suggest mounting the magnets with opposite polarity. YMMV.

Use the washers and #8 construction screws to attach the spindle brackets to the top plate. The screws should not go through the bottom of the brush plate - do not over tighten!

Slide the top plate with brackets onto the spindle and move it up to the top. Now open the flexible pipe clamp, wrap it around the brackets and tighten it until it just closes.

Lower the gentry slowly and ensure the top plate is able to pass the bottom of the gantry. Now tighten the clamp a little bit more. Monkey tight, not gorilla tight. Over tighten and the spindle can be damaged!

The brush fits into the brush plate slot via press fit. It’s close, but not too tight. The brush can be replaced or different length brushes can be used for different jobs.

The press fit works well for me but based on feedback I may want to tighten it up by 0.010" or so.

The tube fittings screw onto the tubing. Trimming the tubing to the proper length depends on how one want to exit the Nomad enclosure.

Trim one of the tube fittings such that it passes through the top plate, a little bit into the brush plate.

PICTURES

mark

P.S.

Here are the STL files:

Spindle Bracket.stl (119.9 KB)

Top Plate.stl (345.6 KB)

Brush Plate.stl (352.6 KB)

[iamhankodonnell (Hank O'Donnell)]

Awesome, awesome, awesome!

[mbellon (Mark Bellon)]

Thanks!

Looking at the mess your machine made (beautiful work by the way), this could really help keep it under control… mine looked similar when I was prototyping these parts.

A dust collector - I have a Festool CT26 (which has a HEPA filter) - and a dust separator (a cyclone) ensure that the best air quality is achieved and the longest life of the filters is possible.

If you look at the @patofoto dust head, it exits out the back. The @FlatBaller version exits out the front. I don’t think there is enough space in a Nomad 883 Pro enclosure to exit out the side like I do (my enclosure is 4 inches wider and 6 inches taller than standard) but the front or back is definitely possible.

I specified a 5 foot piece of tubing so any choice can easily be made. YMMV.

mark

P.S.

Now that I have this done, I will start on the fixed brush.

[imp]

Maybe this will help someone, this is the part list with total from MMC including substitutes for the products mbellon got from TAPplastics. Instead of the 2: 3x3x1 starboard, my list includes 1:3x12x1 HDPE (non-marine grade). Which will have to be cut down. Instead of the 2: 5.5x6.25x0.5 my list includes 1: 12x12x.5 Starboard, which again will be cut down.

I have a big project in the works that is going to be made out of various woods, probably a couple hundred pieces total, haven’t counted yet. Since my cnc lives in my one room apartment with me, I need to finally make a vacuum system. So mbellon, thank you very much for posting this design. I was very surprised at the sticker price though (I shouldn’t have been), which is part of reason I am posting the above parts list.

I’ll be posting pictures, once I have parts in hand, and can find a good way to mount the tubing in a non-modified chassis.

I also have an idea I think that might work as the back part of the brush, using the excess of the hdpe in the above list. I’ll post pictures in a different thread, pass or fail, so it hopefully helps someone.

[mbellon (Mark Bellon)]

Thanks for posting @imp!

The plastic cost from TAP - I can trivially visit them since I live locally - was ~ $20. TAP only charges for plastic purchased.

The magnets are “high tech” and are $$$… but they work SO well.

I’d love to hear your ideas on the fixed brush. I’ve got a simple idea too. Haven’t tried it yet - been sick.

mark

[imp]

Yea, unfortunately I don’t live anywhere near a TAP, so I’m trying to consolidate my shipping. Eh well, more options for others. Especially if I can make a back brush from the left overs.

Oh yea, neo magnets are amazing. I’m a physics student, I’m even currently in a class dealing primarily with magnetism, so I know they are worth it. Just… well… I’m cheap. Still worth it.

Ok, so the idea I have that I think might actually work: a plate that will slide down behind the two posts in the back (tape in pic), that comes down the sides, only thick enough to hold bristles, plus a slot in the back (away from the bit) to hold the second piece which would slot in from the back and would hold the downward bristles. Problems would include the whole thing sliding towards the bit, and being in the way at the bottom of the -Z movement. Possible solution would be to have a U piece going around the back holding all the bristles, and a plate (tape in the pic without the sides) holding it up/forward. Another problem would be it eventually being pushed out of slot, but that could be fixed with adhesive, or any other fastener. I need to prototype to see if any of it works how I think it will. I have some 88 cent poly cutting boards from wal-mart I am going to use for testing.

The pic might be overkill. I was actually going to show every part in painters tape, but I knew that was a bit much. Hopefully it helps, one way or another.

[mbellon (Mark Bellon)]

Oh yea, neo magnets are amazing. I’m a physics student, I’m even currently in a class dealing primarily with magnetism, so I know they are worth it. Just… well… I’m cheap. Still worth it.

300 level EM? Graduate?

I started out in Physics - galactic dynamics (astrophysics). I work in CS - OS internals now.

Ok, so the idea I have…

That’s a good idea. Mine is a single machined piece of plastic. It’s slotted to go onto the gantry bottom plate, has two holes for screws to hold it to the plate and a slot in the bottom for the blush.

I’m playing with a idea for a skirt - flexible plastic - that’s held by a simple paper clamp…

mark

[imp]

300 level EM? Graduate?

I started out in Physics - galactic dynamics (astrophysics). I work in CS - OS internals now.

Nah, undergraduate level still, I wish I was at the graduate level. The VA will pay for my masters, but I still haven’t decided to stay in physics or swap over to chemistry officially. I’d like to do something kind of in the middle. Particle physics, nuclear chemistry, physical chemistry, etc. My dream would be to work in particle physics focused on quantum entanglement for use in communication. Which is supposed to be theoretically impossible, but hey, the earth used to be flat.

You made a good decision, I’m sure you’ve heard the joke, “Whats the difference between a physicist and a large pizza”

That’s a good idea. Mine is a single machined piece of plastic. It’s slotted to go onto the gantry bottom plate, has two holes for screws to hold it to the plate and a slot in the bottom for the blush.

To screw to hold on the plate? As in new holes, the existing holes with longer bolts purchased, or tabs that over hang the gantry bottom plate that are then screwed through?

Because if you meant the existing holes, that’s kind of an amazing idea. I hadn’t thought of it. I wasn’t mentally wanting to modify the base element in anyway, so I was designing for clip-on. But longer screws really isn’t changing anything. And could easily mean a one piece part. Hmm. I wonder if that would work?

[mbellon (Mark Bellon)]

Nah, undergraduate level still, I wish I was at the graduate level.

You’ll get there…

The VA will pay for my masters, but I still haven’t decided to stay in physics or swap over to chemistry officially. I’d like to do something kind of in the middle.

I understand.

Particle physics,

IMHO not a good choice - too many people, too little money, little here in the US anymore.

nuclear chemistry,

IMHO a better choice. Many industrial and research uses.

physical chemistry, etc.

Material physics is one hot area… how to design high tech materials is serious stuff now.

My dream would be to work in particle physics focused on quantum entanglement for use in communication. Which is supposed to be theoretically impossible, but hey, the earth used to be flat.

Ah… the current entanglement record is now in the kilometers range and growing! Yes, they’ve tested communications. It works. They also just published papers showing that it can be easily beaten too.

The universe is filled with not much new and… surprises!

You made a good decision,

It was a tough time. Only about 3 or 4 out of 100 still work in the field.

To screw to hold on the plate?

One piece. The holes go through the the plate and are tapped (threaded). The screw is tightened against the gantry plate and the piece no longer moves. I need to draw it. A slip on. The bottom has a brush.

mark

[dyelton (Donavon Yelton)]

Obtained all of the products for this but are the settings for the toolpath correct? My end mill keeps hanging very shortly after the initial cut. I’ve triple checked the settings and that it is at 10k RPM. Any ideas?

[mbellon (Mark Bellon)]

Obtained all of the products for this but are the settings for the toolpath correct? My end mill keeps hanging very shortly after the initial cut. I’ve triple checked the settings and that it is at 10k RPM. Any ideas?

I just reverified that the posting is correct. The number posted at for 10K RPM and the rates are fine for HDPE and Starboard.

It’s hard to diagnose with this little information but at first blush, not having Z0 set properly would result in an unexpectedly deep plunge would could hang the Nomad.

Can you post a screen shot of your MeshCAM parameters screen? How did you set up Z0?

mark

[dyelton (Donavon Yelton)]

I always setup Z0 by placing a sheet of copy paper between the stock and the end of the cutter and go down until the paper doesn’t move then go up until I can get the paper out.

Here are my settings for the job. First item I’m cutting happens to be the brush plate.

[mbellon (Mark Bellon)]

That sure looks correct.

I always setup Z0 by placing a sheet of copy paper between the stock and the end of the cutter and go down until the paper doesn’t move then go up until I can get the paper out.

This means the Z0 is actually slightly above the stock top… but for this applications such exactness isn’t called for.

Could you please zip up the “.nc” file? I’d like to see the G code.

mark

[dyelton (Donavon Yelton)]

There was another issue involved and Jorge took care of it. Running the brush plate now and about halfway done…runs like a champ!

Thanks for the how-to! I can’t wait to get this on my Nomad and hook it up to the Festool…no more shavings!!

[imp]

Keep us informed how you decide to hook up the tubing to the case. Assuming you have a non-modified chassis?

I just got my parts today for this project as well.

[mbellon (Mark Bellon)]

Any one trying to build this can post or PM me. I’ll be happy to help.

mark

[dyelton (Donavon Yelton)]

I’m almost done running the parts. I have the two plates done and I’m running the two brackets as I type this. I have a day job, a wife, and two small children so it’s been a little slow getting started. I have everything I need to make this sucker and will take pictures once I’m done and post them here. I plan to route it through the back. I haven’t looked, but I’m curious if there is a right angle adapter that I could put on the back of the machine to plug the Festool hose into (I’m certain it exists, I’m just too lazy to look it up at the moment).

@mbellon I’m curious why you don’t mass produce already made kids and make a few bucks? Seems like there would be enough demand to make a few dollars from the project. I’m certain that we all appreciate your willingness to come up with the design, the list of materials, and post instructions for us (I know I’m highly appreciative).

[mbellon (Mark Bellon)]

@mbellon I’m curious why you don’t mass produce already made kids and make a few bucks?

As a teacher, my job is to work myself out of a job. I’m more than happy to give this kind of things away… I can move onto other projects and give those away too!

I haven’t looked, but I’m curious if there is a right angle adapter that I could put on the back of the machine to plug the Festool hose into (I’m certain it exists, I’m just too lazy to look it up at the moment).

That Festool host is a bit hard to find fittings for and right angle I’ve never found. If someone finds them, let me know. I do my fittings “in line”… like this:

Dust collection with Festool and Oneida?

The Festool has some serious air velocity and vacuum so it can easily move the necessary amount of air. A dust head is best in that it achieves the best possible air quality by removing the swarf/dust immediately. Maintaining negative pressure on the enclosure will also provide a safe air experience, just remember to vacuum up the swarf/dust that is visible. Regardless, be sure to allow the vacuum to run for a few minutes after a job finishes to ensure the enclosure is cleared. What you need…

mark

[imp]

Finally completed my dust collection system. Now it is kind of a shame I don’t have something queued to be milled so I can test it without just wasting materials. I decided to run the tube through the back, seems to work.
I also made a water trap system for ~14 dollars. Hopefully it works, doesn’t leak air if nothing else.

[msharp42]

will the ball mill which comes with the nomad work for this ?
or does it have to be a square mill.