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Basic Construction
Lab Assignment - Project Box

Materials -
Wood Sheet - 1/2" ply
Plastic - Acrylic and Lexan - 1/8"
Aluminum Angle - 3/4"

Sheet Metal Screws
Machine Bolts
Sprockets and Chain
Motor

Tools -
Horizontal Band Saw
Stationary Sander
Drill
Metal Lathe

Measuring and Clamping -
Framing Clamp
Table Vice
Carpenters Square
Straight Edge
Metal Ruler
Tape Measure
Calipers

FINAL MEASUREMENTS - Download and print as your reference. All measurements to scale.
Short Side and Aluminum
Long Side and Top
Bottom

machine screws	sheet metal screws
phillips head	slotted	hex/alan/socket

Machine Screws Measured -
Standard Thread Sizes - do not confuse thread sizes for fractions or drill bit sizes
| #4-40 | #4-48 | #5-40 | #6-32 | #8-32 | #10-24 | #10-32 | #12-24 | 1/4"-20 | 1/4"-28 |

Sheet Metal Screws Measured -
Standard Thread Sizes -
| #1 | #2 | #4 | #6 | #7 | #8 | #10 | #12 | #12-13 | #14 | #15-13 | #17 | 5/16" | 3/8" l


Drill Bit Size Conversion - McMaster the maker of everything provides an excellent guide to drill bit size conversions from decimal to fraction to letter to number.

From Idea to Drawing to Material -

+ At this point in this class avoid approaching a tool without measurements. Transfer your ideas paper. Spell out all of your measurements. Length Width and Height. The more you know ahead of time the less time you spend at the tool and the more efficient the whole process will be.

+ When initially prototyping work with standard measurements. Take a look at your local hardware store and online providers and get a sense of scale for the materials available.

+ Use lengths etc. that are easily divided and manipulated.

+ Transfer your mesurements to your material using accuracy. You are only as good as your measuring tools. Experiment with calipers. Use a metal ruler rather than a tape measure to ensure precision. Use a t-square or carpenters square whenever possible.

+ When marking the surface of the material, it helps to make two marks. Like a V. It assures that you are focused on a point rather than a line or circle.

+ When measuring a length for a cut without a square, make two marks at either end of the length, and draw a line between them. This will avoid straying.

+ Base as many of your initial measurements in a FACTORY CUT side of the material. Any cut you will make will not be as accurate as an edge cut by a machine. ( One day maybe )

Step One - Drill the Short Sides

- Use a ultra fine sharpie. Your accuracy is as good as your tools.
- Measure an 1 1/4" from either side in. ( Making a V mark )
- From the center of your mark measure 1/4" up. Do this for both sides. You will only have to mark on SHORT SIDE.
- Clamp both short sides to the table using a block of wood underneath. Align the plastic edges.
- If you attempt to drill plastic without the wood block you will likely crack the plastic.

- Use a 5/32" or 3/16" bit
- Align the bit as precisly as possible. Run a slower speed for plastic.
- Drill until you see wood dust. STOP. You have drilled through.
- Do the same for the other hole.


Step Two - Drill the Long Sides

- Measure an 2" from either side in. ( Making a V mark )
- From the center of your mark measure 1/4" up. Do this for both sides. You will only have to mark on LONG SIDE.
- Clamp both short sides to the table using a block of wood underneath. Align the plastic edges.
- If you attempt to drill plastic without the wood block you will likely crack the plastic.

- Use a 5/32" or 3/16" bit
- Align the bit as precisly as possible. Run a slower speed for plastic.
- Drill until you see wood dust. STOP. You have drilled through.
- Do the same for the other hole.

Step Three - Use the Short Side Hole to Mark the PreDrill

- Running a Pre Drill hole we will avoid cracking the half inch ply.
- Put your 1/2" Wooden Base Plate in the table vise. Small End up. Mark one side TOP and one side BOTTOM.
- Align the Plastic by the BOTTOM. Check all sides for accuracy.
- At this point you may use the Framing Clamp to prevent slippage.
- Since the plastic is already drilled this drill will be pretty easy. For those with conifidence you may hand brace this piece.

- Use a smaller 3/32" or 1/8" bit.
- Align the bit as precisly as possible. You want to hit the center of the previously drilled hole. Run a slower speed for accuracy.
- Drill about a half inch down.
- At this point screw in the first screw before you drill again. This will assure alignment.
- Do the same for the other side.


Step Four - Use the Long Side Hole to Mark the PreDrill

- Leave Short Sides as they affect the overall length of the box.
- Put your 1/2" Wooden Base Plate in the table vise. Long Side up. Mark one side TOP and one side BOTTOM.
- Align the Plastic by the BOTTOM. Check all sides for accuracy.
- At this point you may use the Framing Clamp to prevent slippage.
- Since the plastic is already drilled this drill will be pretty easy. For those with conifidence you may hand brace this piece.

- Use a smaller 1/16" or 3/32" bit.
- Align the bit as precisly as possible. You want to hit the center of the previously drilled hole. Run a slower speed for accuracy.
- Drill about a half inch down.
- At this point screw in the first screw before you drill again. This will assure alignment.
- Do the same for the other side.

Step Five - Drill Holes to Mount the Aluminum

- On the top of each short side measure 1 1/4" from either end.
- Meaure 3/8" (.375) up. Make another mark.
- Clamp the plastic to the aluminum to the table.

- The bit you use here is important. It is the predrill for a specifie tap. Since we are using a 8/32" machine screw then we will use a #29 or 1/8" bit.
- Drill until you see metal shavings. Add a small drop of Cutting Fluid. Drill until you see wood.
- Remove the aluminum and reclamp the plastic. We will now open up this hole larger with a 3/16" or 7/32" bit. Be carful it is easy to crack plastic here. Never touch the bit to the plastic and start the drill with contact. This will grab the plastic. Start the drill early and approch surface with moving bit.
- Do this for the other Short Side.

Step Five - Tapping the Aluminum

+ Clearance drill. A drill bit that cuts a hole just big enough for a screw to pass through without engaging the threads.
+ Tap drill. A bit that cuts a hole of the best size for tapping.
+ Tapping. Cutting threads inside a hole with a tap.
+ Threading. Cutting outside threads with a die.

- Now unclamp aluminum and put it in the tabel vise.
- Add a drop of Cutting Fluid to a hole.
- Take your time in aligning the tap to the hole.
- Apply pressure down and clockwise.
- If you feel pressure back off and untwist. Never force the bit all the way through if you feel blockage. This is a natural part of the tapping process.
- Continue twisting clockwise until through the piece.
- Test the hole with a 8/32" screw. Clean off excess oil.
- Repeat for remaining holes.

Step Five - Assemble Box

- Put all sides on box. Start with small sides.
- Attach Aluminum angle. Use eithe 1/4" or 3/8" - 8/32" machine screws.

Step Five - Attach Top

- Align the top of the box. Checking all sides.
- Clamp the whole box to the table.
- Measure to find the center of the top (2 5/8") and mark.
- Measure in 1/2" (.5) and mark.

- The bit you use here is important. It is the predrill for a specifie tap. Since we are using a 8/32" machine screw then we will use a #29 or 1/8" bit.
- Measure and drill both sides.

- Unclamp. Remove aluminum angle and put in vise.
- Add a drop of Cutting Fluid to a hole.
- Take your time in aligning the tap to the hole.
- Apply pressure down and clockwise.
- If you feel pressure back off and untwist. Never force the bit all the way through if you feel blockage. This is a natural part of the tapping process.
- Continue twisting clockwise until through the piece.
- Test the hole with a 8/32" screw. Clean off excess oil.

- Reclamp Top to table.
- Open up this hole larger with a #29 or 1/8" bit. Be carful it is easy to crack plastic here. Never touch the bit to the plastic and start the drill with contact. This will grab the plastic. Start the drill early and approch surface with moving bit. Open other side.

Step Five - Reassemble Box

- Attach Aluminum angle. Use either 1/4" or 3/8" - 8/32" machine screws.
- Attach Top