P08456 Underwater LED Light
R.I.T. MSD-II
Manufacturing Plan
P08456:
Jeremy Schiele
Justin VanSlyke
Jonathan Lent
2/6/2008
Standard Practices 3
Hinge Manufacturing Procedure 4
Bullet Housing Manufacturing 5
Thruster Housing Manufacturing 6
LED Housing Manufacturing 6
Anodizing Process 7
Electrical Component Manufacturing 7
Final Assembly Tree of Light Unit 8
Appendix A: Electrical Drawings
Electrical Schematics 9
Views of Gerber Files 10
Appendix B: Mechanical Drawings
Bullet Housing 12
LED Housing 13
Thruster Housing 14
Hinge Arm 15
Hinge Base 16
The purpose of this document is to be a history of the work that went into the original production, and to provide a guide to the remanufacture, of the LED light unit originally designed and manufactured by P08456. When remanufacturing individual problems may occur and will need to be dealt with on an individual basis.
I. Mechanical Components
- Dimensional Tolerances
- Component Critical Tolerances: These tolerances will be held to within spec in order to verify the end functionality of the product.
- Non-Critical Tolerances: Will be held to within drawing spec, X.XXX=0.005 and X.XX=0.01 if otherwise unnoted.
- Material Condition
- Surface finish will not be rough enough to interfere with anodizing process and/or finish.
- Cosmetic imperfections will be tolerated, providing that they in no way interfere with the overall functionality of the part/interactions with other components.
- CNC Machining: Due to the need for multiples or single parts to be machined, Computer Numerically Controlled machining will be used.
- Prototype Verification: Before any CNC operation is conducted, a sample part will be run with the final program, written by the CNC operator (J. Bonzo). This part will be checked for dimensional tolerance and stability for all dimensions available.
- Multiple Parts: After a sample has been verified multiples may be machined, operation of machine can be run by students of P08456 with proper knowledge of machine.
- Anodizing Finish: A protective anodizing layer will be applied to resist any dissimilar metal corrosion. Type-II thickness < 0.0001 in.
II. Electrical Components
- Component Location: Surface mounted components (SMC) will be placed onto its solder pad within tolerances so as to not inhibit electrical performance.
- Orientation: Parts will be oriented so as to not interfere with functionality.
- Solder Wetting: Solder will be heated to correct temperature to allow for complete adhesion between the PCB and SMC.
- Handling: Both PCBs and SMC parts shall not be damaged in handling.
III. Component List with Manufacturing technique required for production
- Bullet Housing: CNC Machined
- LED Housing: CNC Machined
- Thruster Housing: CNC Machined
- Hinge Part 1: Hand Machined- Mill
- Hinge Part 2: Hand Machined- Mill
- Power Supply Board: Outside vendor & Hand populated
- Micro-controller Board: Outside vendor & Hand populated
- LED Driver Board: Outside vendor & Hand populated
- LED Board: Outside vendor & Hand populated
Hinge parts are machined by hand on a vertical milling machine such as the Bridgeport. Reference Hinge Arm and Hinge Base drawings for dimensions and geometry.
· Cut stock to rough dimensions: 1.25 in. x 0.5 in. x 0.75 in. (L x W x H) for base, 1 in. x 0.5 in. x 0.5 in. for the arm.
· Hinge Base (4 pcs.)
o Secure stock in vice with parallel bars
o Level off one side with end mill
o Flip stock 180 degrees
o Mill stock down to dimension (0.625 in. or 0.375 in.)
o Repeat for other side, same process as above.
o Overhang part out of vice
o Mill protruding end flat
o Flip stock 180 degrees again
o Mill protruding end until 1 in. length is reached
o Choose parallel bars that leave less than 0.25 in. between top of bar and top of vice.
o Secure part with 0.625 in. going up, and 1 in. going along the vice.
o Find zero on right hand and front side of part (front right corner)
o Mill out fist side of tab (0.375 in. in from right side) to a depth of 0.375 in., leaving a 0.25 in. flange at the base.
o Mill out second side of tab (0.625 in. from right hand side) to a depth of 0.375 in., leaving a 0.25 in. flange at the base and between the two cuts just made.
o Remove end mill and replace with center drill
o Zero mill to front right corner again
o Center drill at 0.1875 in. from right side and 0.1875 in. from front (this would be on the right flange)
o Center drill at 0.8125 in. from right side and 0.1875 in. from the front (this is the left flange)
o Replace center drill with #28 drill bit and drill through the piece for both holes just center drilled.
o Remove piece and flip away from you 90 degrees, so the tab and the flange are between the jaws.
o Zero a center drill to the top right corner of the tab
o Center drill 0.125 in. from the right side of the tab and 0.1875 in. from the far side of the tab.
o Replace with #28 drill bit and drill through the piece at this location as well
o De-burr all edges and piece is complete.
· Hinge Arm (4 pcs.)
o Vice down stock on parallel bars
o Level off one side with end mill
o Flip stock 180 degrees
o Mill stock down to dimension (0.375 in.)
o Repeat for other side, same process as above.
o Overhang part out of vice
o Mill protruding end flat
o Flip stock 180 degrees again
o Mill protruding end until 1 in. length is reached
o Replace end mill with center drill and zero to bottom left corner of piece
o Center drill 0.1875 in. from left side and 0.1875 in. from bottom
o Replace with #28 drill bit and drill through the piece at this location
o Flip piece up in the stock (long way down) with parallel bars below to keep it true.
o Replace drill with center drill and zero to bottom right corner of top face
o Center drill 0.1875 in. from right side and 0.1875 in. from bottom.
o Replace center drill with #36 drill bit and drill to a depth of 0.6 in.
o Remove piece from vice and de-bur all edges
o Using a #6-32 tap, tap the 0.6 in. blind hole in the end to a depth of at least 0.5 in.
o Remove tap, blow out threads and piece is complete.
Method: The bullet hosing is machined using a CNC lathe with two live spindles. The exact machine used was the Mazak Super Quick Turn 15M-Y Mark II. Two steps are involved in the CNC process:
Step 1: Sealing surface o-ring groove, exterior diameter, and internal volume are removed from part. 4-40 standoff mounting holes and 8-32 lens cap retaining screw holes are located and spotted with an oversized drill bit.
Step 2: Part is reversed, and unfinished end is exposed to be cut. The ¾-16 bulkhead connector hole and the curved contour are cut into the part.
Once CNC operations are completed the following operations can be done:
- 4-40 tapped holes are drilled using a # 29 drill bit
- 4-40 holes are tapped and bottom tapped to assure enough threading
- 8-32 holes are drilled to a depth of 0.75 in.
- 8-32 holes are tapped
- ¾-16 hole for bulkhead connector is tapped. Part should he held in lathe, while tap is secured in chuck and part is manually spun as tap is pressed into it.
Refer to Bullet Housing drawing for dimensions and geometry.
Method: The motor housing for the thruster being designed by P08454 is CNC machined using two types of operations. All processes and programming contained therein are handled by the staff of the Brinkman Manufacturing Lab. Part geometry is conveyed either by part drawing or by IGS file (an output from Solid Works).
Operation 1: Using Mazak Super Quick Turn 15M-Y Mark II all concentric geometry is cut into part. Machining black is cut with 2 in. of extra stock for the Mazak jaws to hold onto, these portions will later be cut off. The exposed internal volume (for magnetic coupling) is bored out to final dimensions, but internal cavity for motor is not because it is inaccessible.
Operation 2: Before machining, extra stock used for holding part in previous operation is cut off. Using the Okuma Ace Center MB-46VAE vertical milling CNC. Part is centered in 4 law chuck fixed to table of milling machine. Face is machined flat per drawing and motor cavity is machined out. The part is then removed, and turned upside-down so the tabs can be machined into prop end of housing, and mounting thru holes and counter bores machined into inside of motor housing.
The LED Housing, which is also referred to as the Lens Cap Housing holds the LED board, and is secured to the Bullet Housing with an o-ring to seal light unit.
Method: Similar to Thruster Housing, the LED Housing is machined using 2 CNC operations, but with the addition of a manual operation at the beginning and end.
Operation 1: The end that will eventually be inserted into the Bullet Housing is to be machined manually on a lathe. The amount of stock left on the unfinished end is not critical, just so that it is enough to make the final part (0.80 in. overall length minimum).
Operation 2: On the Mazak 15M-Y, the concentric geometry is cut into to raw end of the machined blanks prepared in operation 1. Features cut in this operation include thru hole, final length, and counter bore that lens sits in.
Operation 3: Using the Okuma MB-46VAE the part is centered in a small 3 jaw chuck fixed to milling machine table. Features cut into part include 8-32 thru holes, o-ring groove, and contours surrounding thru holes that act as counter bore for screws.
Operation 4: On lathe, snap-ring groove is manually cut into part. After all operations, parts are de-burred and cleaned in soap solution.
NOTE: Operations 2 and 3 are handled by Brinkman Lab staff.
Anodizing process is handled in conjunction with BSV Metal Finishers Inc. of Rochester, NY. Anodized finish is Mil Spec Type-II black, thickness < 0.0001 in.
Method: Thoroughly cleaned parts with tapped holes plugged, are hung on an electrically conductive rack. The parts are dipped into an acid bath with an electric current run through them. The electric current is a catalyst for the formation of a protective layer of oxidization on the surface of the aluminum. The current also enables a thicker than naturally occurring layer to be formed.
Method: Electrical components and printed circuit boards are designed using Atrium Designer; file format used for manufacturing the PCBs is DXF-274 Gerber Files. These files are sent to the manufacturer (Advanced Circuits) who builds the specified board/s according to the drawings sent.
PCBs are populated manually in the Surface Mount Technology (SMT) Lab, a part of the Center for Integrated Manufacturing Studies (CIMS).
Electrical Schematics and views of Gerber files are given in Appendix B
Electronic Gerber files used for manufacturing are available on the EDGE website:
http://edge.rit.edu/content/P08456/public/Electrical%20Design%20Information%20Page
The final assembly of the light unit is performed manually. The following is an assembly tree for the light unit.
Figure 1: Electrical Communications Schematic
Figure 2: Microcontroller Schematic
Figure 3: LED Board PCB Schematic
Figure 4: LED Driver Board Schematic
Figure 5: RS 485 Communication& Micro-controller Board Schematic
Figure 6: Power Regulator Board Schematic
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