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X-Carve

X-Carve topics and Classes. If you have any troubles with the X-Carve, please report it. If you have any questions or suggestions, please email davelers@gmail.com.
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Sign In

The first step to using the X-Carve is to "sign in", you can also "request" an open time slot ahead of time.

Signing in to use the X-Carve lets anyone interested in using it know that it is currently in use. All you need to do is click [new], enter your first-name last-initial, click Preview and Post Now!. The returned page includes a Login to Easel link. The current setup gives everyone a 2hr block of time. If you need more/less time, please add a note to the comments.

Requesting a time slot helps to insure that you can sign-in/use the X-Carve when you want. Requesting a 2hr time slot can be done as a reply to the current users sign-in (auto filled form) or as a new post. When using [new], replace the default title with "'month-day' request" and replace the default comment with the requested time frame (hr:min - hr:min). Please limit requests to the current or next day that Makerspace is open.
[ page | comments (7) - Monday, 18-Nov-2019 | top ]admin

Machine Setup

Machine SetupIf you get prompted to setup the X-Carve; use the pictured settings (click to enlarge) and choose no homing, manual spindle control and no z-probe.

If the X-Carve is cutting too deep, the lead screw setting is wrong and needs to be set to Acme (coarser thread/less revolutions than M8). I'm not sure what is causing it, someone using the default/wrong settings or the X-Carve loosing its settings and falling back to the default settings.
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Drilling holes

Drilling holesDrilling holes using the hole tool, or the convert to drill holes app, is done with an 1/8" shank circuit board drill (NOT with a router bit), the router speed set to 1, and the pictured custom cut settings. While these settings have only been tested on wood, they should work with acrylic as well... Swarf can accumulate on the bit when drilling acrylic, a shot of compressed air at the top of the stroke prevents it.

The Plunge rate should be at least 2x the Recommended Plunge rate (faster for < 1/8", slower for >) and the Depth per pass should be the same as the Cut Depth. Without these settings the bit will not move smoothly or fast enough (i.e. will get hot and burn/melt the material).

For through holes, increase the material thickness so that the Cut Depth and Depth per pass can be large enough for the body of the drill to make it through (VS just the tip, .8" VS .75" in the example). Note: the CNC does not use the material thickness info, just the depth of cut info.

For mixed cut/engrave/drill, create a duplicate workpiece so that the drilling is on a seperate workpiece.
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Dust Collector

Dust CollectorThe new dust collector swings out of the way for easy bit changes and provides good cut visibility.
  • Loosen the side knob and swing the plate out of the way
  • Insert/tighten the bit and set its start location/height
  • Turn on the CNC controller to lock the stepper motors
  • Swing the plate over the bit until the bit is centered in the hole/plate
  • Set the plate just high enough to clear all clamps/screw heads.
  • Insure that the space between the router body and plate is >= depth of cut.
  • Tighten the side knob.
In the example the plate is relatively high because it needs to clear the knobs (bad idea), luckily there was enough clearance to make the desired depth of cut... There are some new low profile hold down clamps to help with potential clearance issues... Added a rotational stop to simplify bit/plate alignment... Widened the bit slot for the 1/2" V bits, even the collet nut will fit when the flats align with the slot.
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Repetitive Cut Fixture

Repetitive Cut FixtureThe fixture is a combination square and spoil board that allows routing multiple pieces using the same home position. While the square is not particularly square, it does allow for reasonably accurate repetitive (re)positioning. The example is one of three marble mazes that were routed with a bullnose bit and then repositioned and through cut with a straight bit.

The fixture has 5mm holes on 75mm centers (same as the X-Carve) that allow positioning and clamping anywhere on the table. There are also some special 2 hole clamps for clamping 1/4 and 1/2" stock to the fixture (example stock is 3/4).
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Polylines

PolylinesPolylines (12min) cut cleaner and faster than segmented lines (32min). In Easel, the only way to cut inside or outside of the line is with closed polylines. Polylines show up as an unbroken path when Simulate is clicked in Easel. Hidding the material and tilting the preview should show a single vertical start/finish line.

While Inkscape has a Path Combine/Break Apart that looks like it works, and that I thought had worked for me in the past, nothing I tried in Inkscape got me an unbroken path in Easel... The DXF Segmented Line Fix in Inkscape video shows a couple of ways to fix/join segmented lines. The shift-select adjacent segment, box/select node, shift-J to join method may simpler to do in CAD (e.g. clicking adjacent segments can fix or join them, depending on the tool selected).

Another solution, in this case, is to open the dxf or svg in (the free version of) QCAD, add a layer and use the polyline tool to rebuild the shape as a closed polyline. Delete the layer 0 shape, save and import into Easel. For shapes with curves, I use an old CAD program (AutoSketch 9) to join the segments into a polyline (save as dxf and import into Easel). Apparently QCAD can do this, but not with the free version.
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Center Origin

Center OriginThe default Easel origin is the bottom left of the material. Centering any multiple object drawing on the material can be a PITA, especially when text is involved. While using a center origin is not visually intuitive, it is relatively easy to setup. The easiest way is to select all the objects in the drawing (Ctrl A), select the Shape tab, click the center circle and enter 0/0 for X/Y. While this works in simple cases, it is not very precise (center circle and origin are not aligned) and probably won't work as expected when text is involved.

The problem with text is that it doesn't center (its bounding box does) or center isn't the best place for it. For precise center origin alignment of text, or any set of objects: add a square to the drawing, set Cut to Outline and Depth to 0, set Shape to a Size that's bigger than all bounding boxes (blue lines), e.g. material size (if that's big enough). Use Edit > Center to Material to center it on the drawing, select all objects and (as above) set Shape position to 0/0 (center circle selected). While the added perimeter shape shows up in the drawing, the depth was set to 0 so it won't be cut/visible in the preview/simulation (deleting it is optional).

Mark the center of the material with a pencil, align the router bit over the mark and hit carve. Center origin is also handy if you want a reference point that can be used on both the X-Carve and the laser, e.g. route paths/pockets and then laser cut and/or engrave the part (or vice versa). If one or the other operation will cut away the pencil mark, do that one last. While the laser default origin is the top left, it has a center-center option.

Note: the only reason for work area and material dimensions is for visualization and to insure everything will fit. The only information sent to the X-Carve is how and where it should move the router (example image). When designing stuff in Easel, reducing the Machine Work Area dimensions to match the material dimensions will make previews and simulations easier to see (set to 1x1mm for the example image).
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Router Bits

Router BitsGenerally, cutting wood works best with straight two flute bits and plastic with single flute up-cut spiral bits. Down cut spiral bits can provide cleaner cuts in wood and may be worth the extra cost in some applications (I'm not sure the X-Carve is rigid enough for them to make a difference). Compression (up/down spirals) bits are worthless on the X-Carve, they are only beneficial on single pass (full depth) through cuts.

Wood pocket cutting works reasonably well with a 3/8" T-slot cutting bit. The primary reason is the relatively large cutting surface on the bottom of the bit. Most specialty surfacing/bottom cleaning bits are too big for the X-Carve. While 1/2" open center mortising bits are another option, they are typically significantly more expensive and the current Easel algorithms favor 3/8" (over 1/2 and 1/4")... Nov '19: anything over 1/8" takes longer, i.e. there's no advantage to using a larger bit.

Inventables bit articles:
Carving Bits 101 - Bit Basics
Carving Bits 201 - Feeds, Speeds, and V-Bits

Cheap Bits:
AliExpress : Milling Cutters
single flute   single flute 10pcs (e.g. 1/8 carbide $6+)
straight two flutes   straight two flutes 10pcs (e.g. 1/8 carbide $9+)
1/4" shank, 3/8" pocket cutting
The straight two flute HUHAO (Hozly looks very similar) brand is better than Fdit (Walfront looks very similar). Both the tip and edge grinding is simplified/slightly flawed/cheaper on the Fdit's. More facets on the ground shape generally means higher quality and a few bucks more... That said, the Fdit's seem to cut fine. The Weix spiral two flute bits are ground well (better than Kitbakechen).
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