Category Archives: Shapeoko

Shapeoko 3 Dust Shoe

Since receiving an updated board from the lovely folks at Carbide 3D I’ve been running my Shapeoko 3 a great deal more than I was previously. This has lead to my small shop being covered in a progressively thickening layer of fine wood dust and aluminum shavings. If I had a dedicated wood shop this wouldn’t be an issue, but my small shop pulls duty as my R/C build area, my electronics shop, my wood shop, my metal shop, and a Ham radio shack…

I needed something to contain all the dust.

There’s a handful of dust shoe  designs available (in both plan form and assembled), but in my opinion nobody has nailed it. The flaw I’ve seen is attaching the dust shoe to the router using the two fasteners that attach the spindle lock.

DW611 Bottom Screws

Sure, it will probably get the job done, but I wanted a mounting solution that would be slightly more robust; especially since I wasn’t going to be using uber thick acrylic or aluminum.

So as I always do, before starting into the design I laid out a list of requirements to meet.

  • Mounts to either spindle mount, or Z-carriage…not spindle
  • Works with 1-1/4″ vacuum attachments (since I’m using HD Bucket Head as suction)
  • See-through (I like to be able to see the business end)
    • This means acrylic or polycarbonate.
  • Use ‘brush strip’ as a skirt (looks cool, works well)
  • Brushes can be easily changed for different heights
    • Probably attach with magnets (not a big deal since I don’t run any ferrous materials on the shapeoko)
  • Relatively inexpensive
  • Easy to machine (no crazy 2 hour 3D tool paths).
  • Must work with stiffened Z Axis Carriage plate.

Then I went into my shop, sat down, and stared at my machine for 30 minutes, took some measurements, made some sketches, and at the end had everything designed in my head with critical dimensions on paper.

This is how my mind works...
This is how my mind works…

Moved to my desk and about an hour had everything modeled and CAMd up.

Completed Models for Assembly Check
Completed Models for Assembly Check

Models done, I put in an order to McMaster for some brush strip and ran off to Home Depot for some .200″ thick acrylic, 1/8″ aluminum angle, and magnets (does anyone know how they work yet?).

Once the brush strip arrived, I did some test cuts int he acrylic to work out what kind of a fit I needed for the brush and the magnets and to try out some speeds and feeds in the acrylic. I ended up increasing the pockets for the magnets .005 over their actual diameter to get a slip fit. The brush strip was hard rubber and gave a nice snug fit at net sizes.

Then ripped the sheet of acrylic down to manageable sizes on the table saw and buzzed out the parts on the shapeoko. The aluminum angle was a little trickier, but I was able to get the radius cut out in acceptable fashion. I transferred the 8 holes from the machined acrylic to ensure alignment (I haven’t really done much drilling on the shapeoko…that’s something to experiment with later).

This project left me with a love-hate relationship machining acrylic. Your job can be chugging along with a beautiful surface finish and next thing you know you’re melting the acrylic to the tool and your surface finish goes to hell. I’m still running a 2-flute end mill…so I need to give it another go with a single flute plastic endmill, or maybe it’s as easy as tweaking speeds and feeds (probably up my feed rate).

Once everything was assembled I jumped on the opportunity to run some test cuts…and…NO DUST! I was also a little surprised because I feel (no hard evidence) like it quieted the machine down a bit.

After some test cuts I found that the brush strip was a little long for what I needed (I had ordered the 3″ tall stuff) so I decided to trim it down; but that was the only adjustment I had to make.

I plan to make at least two more shoes for varying length bits with 1″ strip, 2″ strip, and then the 2.5″ (trimmed) strip I have will round it all out. The next parts I make will also use proper Acrylic welding adhesives.

Finished up, running the router to make sure no cooling air is blocked and that theres clearance to the spindle.
Finished up, running the router to make sure no cooling air is blocked and that theres clearance to the spindle.
All finished, I thought I would need another support for the vacuum hose, but turns out the dust shoe was plenty.
All finished, I thought I would need another support for the vacuum hose, but turns out the dust shoe was plenty.

Shapeoko3 Z-Axis Carriage Stiffeners

Once I got comfortable with the basics of running a CNC (CAM, manual g-code, homing, zeroing, etc) I wanted to start to push the Shapeoko3 to reach the limits of material removal and surface finish. I started off with a block of aluminum, a 0.25″ 2 flute end-mill and just started entering g-code to jog the machine back and forth at set depths, widths of cut, router speeds, and feed rates. This quickly confirmed the difference in stiffness between the X and Y axis.

Despite being made from heavy stamped steel the Z-Axis carriage was flexing during cuts in both the X and Y directions resulting in loads of chatter at high material removal rates, and poor surface finish during finishing passes. To fix this I decided to build a pair of stiffening gussets that would tie the carriage plate directly into the spindle (while trying to keep things somewhat clean looking).

Initial sketches and dimensions taken from Shapeoko.
Initial sketches and dimensions taken from Shapeoko.

The stiffeners would run from the top of the carriage to just below the spindle mount. They’ll be notched to wrap around the spindle mount so that the attach fasteners will see lower loading. They’ll tie into the carriage plate at 3 locations with countersunk hardware.

Whipped up a model in Inventor and  got everything CAM’d and made a trip to my local material supplier of choice: Shapiro Supply. I cut out the right hand support first, tweaked the CAM, and cut out the left hand a day later. The first RH part required a some filing to fit it to the spindle mount the LH part with slightly revised G-Code (to repeat finishing passes and make up for machine flex) came out quite nicely.

STEP Files for anyone interested: Shapeoko3_ZCarriageStiffeners

Model for LH Stiffener after tweaks.
Model for LH Stiffener after tweaks.

Then I stripped the Z-Carriage off of the machine.

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Centered the spindle mount and test fit the stiffeners.

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Measured the offset of the stiffeners from the side and added half the thickness to the measurement (to give me the center line of the stiffener that I could transfer over to the carriage plate). Applied some layout fluid to the backside of the  and scribe a center line. Center punch holes and drill pilots.

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Dykem the mating surface of the stiffeners and transfer holes. Drill pilots in the stiffeners and open with tap drill. Tap for the screws I’m using (#8-32).

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Another sanity check after I finished tapping the holes in the stiffeners to make sure everything fit together before countersinking the holes in the carriage plate and laying out the holes that would tie it into the spindle.

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Layout the fasteners that will attach the stiffeners to the spindle mount.

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Drill, Tap, Countersink all fasteners.

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Re-install the Z-Axis carriage. Done…almost.

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After I installed the carriage I was still a little dismayed at how much movement  was present in the Y direction. Upon further examination I realized the movement was no longer the carriage plate flexing, but in the V-wheels…I thought I was stuck with it and the slop was just inherent to the design of the machine. Then while applying pressure to the spindle I noticed a slight popping coming from one of the wheels (that was associated with ~0.010″ of movement). I assumed something was loose, and tore back into the Z axis.

I tried to trace down where it was coming from: did I have a loose fastener somewhere…? I completely disassembled the Z Axis again and re-assembled, re-tension all of the v-wheels on their rails etc. The play was still there, the ‘popping’ was still there. It appeared to be isolated to my lower LH V-wheel…so I concentrated on that.

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When I disassembled the suspect V-wheel,  I took some measurements and the shim between the two bearings mic’d at 0.042. Measuring the delrin V-wheel itself, it checked with a 0.030 wide internal ridge. The 0.042 shim was to thick and was allowing ~0.012 of float between the bearings.

vwheelspacingjpg

I changed out the oversize spacers with thinner washers (which should result in a nominal fit to a  slight pre-load on the bearings) and the remaining slop was gone.

Chatter was greatly reduced allowing me to increase material removal rates, and finishing passes could easily take full depth cuts on 0.25″ thick stock while still maintaining great (for a desktop machine) surface finishes.

Video shows me machining a pocket in 6061-T6 at 20ipm, 0.10″ width of cut, 0.050″ depth of cut.

This was one of the first tests I did after the mod and have since settled in on 30ipm, 0.10″ depth, and 0.050″ width cutting 6061.

Now if only I could control the spindle speed through the software…

Shapeoko 3 Dropped Connection

I received my Shapeoko 3 in June of 2015 and couldn’t wait to get it up and running in my shop. The design is solid, much stiffer to the X-Carve and Shapeoko 2. The machine gave me the ability to quickly and accurately cut wood, aluminum, brass, circuit boards, and plastics.

Starting out running simple jobs that didn’t require any tool changes I began to notice that the connection would drop upon turning off the DWP611 router that I was using as a spindle. This would result in a lost zero, and would occasionally drop the spindle a couple inches letting the cutting tool gouge the work. It made running complex jobs requiring tool changes nearly impossible.

I contacted carbide 3d and they recommended adding ferrite beads to all the cables. I ordered a USB cable with ferrite chokes build in from amazon and a bag of 7mm clip on ferrite chokes for the router and any other cables that needed them.

I installed everything, and the problems persisted. I continued by trying just about everything short of buying a big universal power supply.

  • Plugging the router into a separate circuit in my house.
  • Adding chokes to the stepper motor wires.
  • Adding multiple chokes to all wires.
  • Removing the controller board from the machine and moving it behind a piece of sheet metal as a shield.

After these solutions failed, I sent several emails to Carbide3d that all went unanswered.

Finally, I landed on a post in the Shapeoko forums where a user said he had added a shielded three conductor extension cord to his spindle. Unfortunately he didn’t provide any instructions (so hopefully this will help those who are hesitant).

THIS INVOLVES WORKING WITH 120V AC POWER. INCORRECT WIRING CAN KILL YOU! IF YOU’RE NOT SURE EXACTLY WHAT YOU’RE DOING GET SOMEONE WHO DOES TO HELP.

I dug an old PC power cord out of a cabinet and went to work. Before I made anything permanent I mocked everything up. The router uses crimp on spade connectors, and luckily I had a couple from a previous project. I did have to bend the power wire connector on the switch 90 degrees to fit it into the location of the original. Once finished I power cycled the router and…NOTHING. No connection drops!

Mocked Up and Ready to Test
Mocked Up and Ready to Test
Crimp on Connectors tying in Power, Neutral, and Ground.
Crimp on Connectors tying in Power, Neutral, and Ground.

After everything was working, I tidied up the wiring I bit. I had to slit the router casing using a Dremel to allow the ground spade connector to sandwich between the router cap and metal body. Once lined up I used a dab of hot glue on the back of the connector to hold it in place.

Slot in router cap to allow terminal to clamp up on router body.
Slot in router cap to allow terminal to clamp up on router body.

I located the switch back in its original location, routed the wires in a manner that they wouldn’t be pinched, and reinstalled the top cover. Once the cover was installed, I metered continuity between the ground prong and router body to ensure the terminal hadn’t shifted out of place.

Done, ready to re-install the top cover.
Done, ready to re-install the top cover.

I’m still using a ferrite bead on the power cable, and the USB cable with built in chokes. Since the mod (~4 months) I’ve only had one or two dropouts, and at least one was caused by static from my shop-vac hose when vacuuming up Kydex (plastic) chips during a job. Compared to the drops every-other power cycle I consider this a success.