Liberty, Equality, & Justice for ALL
Tux-Lab Manufacturing Project
- Remember that time is money -
Benjamin Franklin 1748

Bottle Opener Rev 3
Apr 23, 2012

The mouth lip was modified for better clearance and the center cavity was removed to help speed up the machining process and the logo were modified to reflect the coarser resolution of electrochemical etching. The height was also reduce to better fit the raw stock height.

Bottle Opener Rev 4
Apr 23, 2012

The shallow mouth opening has too steep of an angle and tends to peal the cap back. The mouth opening was elongated to give better leverage to lift the cap.

Prototyping - ElectroChemical Etch
Apr 13, 2012

Electro-Chemical Etcher - McMaster
Starter Kit 2amp Hand Marker $73.80
16oz Stainless Steel Electrolyte $10.77

Raw Stock, Machined, Deburred Burnished & Etched

Prototyping - Machining
Apr 13, 2012

The mouth of the bottle opener was based off the dimensions of the can opener tool on a Leatherman Sideclip. A few laser cut acrylic prototypes were made to test the mouth geometry for bottle cap engagement.

The bottle opener in the foreground was the very first prototype drawn with a commercial 3d cad before switching over to FreeCAD.

Op1 and Op2 Completed

Op3 Completed after numerous unsuccessful attempts in the background.

g-code programming
Apr 07, 2012

Bottle Opener Speed and Feed Calculation

Tool SFM Diameter RPM Feed per Tooth # of Flute Feed (ipm)
Maritool .250” 4F TiAlN 315 0.250 4813 0.0014 4 27
Maritool .125” 4F TiAlN 315 0.125 9626 0.0005 4 19.3
Maritool 2.48 Shell Mill - ACK300 Inserts 300 2.480 463 0.0060 5 13.9

Fixture Machining
Tool SFM Diameter RPM Feed per Tooth # of Flute Feed (ipm)
Kennemetal .500” 3F HPF37 800 0.500 6112 0.0040 3 73.3
Kennemetal 2.5 Shell Mill - K110M Inserts 3000 2.500 4584 0.0060 3 82.5
Maritool .375” Drill Mill 4F 300 0.150 7640 0.0005 4 15.3

SFM Diameter RPM Feed per Rev
Feed (ipm)
Iwrin #36 Drill 200 0.1065 7174 0.0040
Irwin #25 Drill 200 0.1495 5110 0.0060

Bottle Opener Rev 2
Apr 06, 2012

Modify radius and location of head and tail holes for fixturing with socket screw during op3, machining of the profile.

Tool Path Planning
Apr 04, 2012

Before the g-code can be written, the machining tool path needs to be determined. A total of 3 cutting tools will be used. A shell mill to smooth both the top and bottom, a .25" end mill will perform most of the rough profiling, and a .125" end mill will perform the final profiling pass.

Each cutting tools has a specified cutting parameter. For both the .25" and .125" end mill the recommended radial cutting depth is 20% of tool diameter. Base on this information, LibreCAD was was to draw out the tool path.

In g-code, the tool path is represented by a series of linear and circular moves. Each transition point, ie where straight line meets a curve or where curves of different radius meets, on the tool path needs to be specified in terms of its X-axis and Y-axis coordinate. If the the next move is a circular move, the radius will also need to be specified. The process of dimensioning the transition points can be quite tedious.

Raw Stock & Cutting Tool Ordering
Apr 03, 2012
Stock - Metal Express
304ss flats, 4” x 0.5” x .125”, 100pc @ ~1.865 $86.00

Tooling - Martitool
.125 Double End 4F Carbide End Mill TiAlN, 2 @ 8.51 $17.02
.250 Double End 4F Carbide End Mill TiAlN, 1 @ 14.82 $14.82
45 deg Shell Mill Insert, ACK300 grade, 5 @ 10.70 $53.50

Fixture – HomeDepot
6-32 Hex Socket Screw $0.65
10-24 Hex Socket Screw $0.86
6-32 Irwin Drill/Tap Kit $4.97
10-24 Irwin Drill/Tap Kit $5.47

Tooling – Martitool, 2nd Batch
.125 Double End 4F Carbide End Mill TiAlN, 4 @ 8.51 $34.02
.250 Double End 4F Carbide End Mill TiAlN, 2 @ 14.82 $29.63
.125 4F Carbide Drill Mill 120Deg 1 @ 8.44 $8.44
3.3mm .1299” Cobalt 130deb Screw Length Drill TiAlN 2 @ 7.58 $15.16
USPS Priority Mail $12.45

Fixture Machining
Apr 03, 2012

Two Fixtures:

Step Soft Jaws for:
Op 1 - Side A Facing
Op 2 - Side B Facing, Hole & Pocket Machining
Profiling Fixture for:
Op3 - Profile Machining

FEA of Design Options
Apr 03, 2012

While waiting for the cutting tools to arrive. The effect of hollowing out the bottle opener was explored with Z88, an open source FEA software. Z88 is available in Debian, but Z88Auora the newer gui version of Z88 is only available as a Ubuntu package. Luckily, the Z88 was able to install under Debian.

After many hours of bumbling around, some sort of an answer was derived. The accuracy of the answer is unknown, but the picture look pretty. The skeletonized bottle opener does deflect more, but not that much more than the solid body version.

The ascii mesh was created using FreeCAD and imported into Z88. After reading through documentation, it appears that while Z88 is an open source software, Z88Auora is a binary only distribution.

TheCuriousPenguin - 2012
Free as in