This week, our assignment was to make a crate made of planks of lumber. Like with the apron, this assignment was completely new to me, and we decided to go for the beginner difficulty level for this project.

Procedure:

We started off by getting wood that had already been cut to the appropriate dimensions. WE used nine 14.5” long pieces and six 12” long pieces of 1×4 lumber and 4 10” pieces of 2×2 lumber.

We decided that we wanted to round out the edges of our wood before assembling the crate so that there would not be any sharp corners. We did this using the router and a curved router bit that made a curve with radius of about 0.5”.

After we did this, we used 100 grit sandpaper on a power sander to better round out the edges and to smooth all the surfaces.

We then decided that we were ready to begin assembling the three rectangles that would make up the sides of the box. We marked where we would put screws on each of the 12” long pieces, and then practiced screwing together two scrap pieces of wood.

To assemble our actual wood, we used the corner clamp to line up the two pieces of wood. We decided that we didn’t want the corners to line up exactly to create a different look to our crate.

We then used a 1/8” drill bit to make a pilot hole in the wood. We then used a larger drill bit to create larger holes for the head of the screw (so that they would be flush with the wood surface). Lastly, we used 1.25” screws to attach the pieces together. We repeated this process for each side of the box that needed to be assembled.

Finally, we were able to assemble all the separate components. We used three of the 14.5” long pieces to make the base of the crate. The 10” pieces were going to be the support for the three rectangular pieces and would allow for a 2mm gap between them.

We decided that we wanted the screws to be on the inside for aesthetic purposes. This was difficult to do though because it was hard to get the drill in the right position.

We then used 24 grit sandpaper to get every edge to be very smooth.

The last step in the process was to stain the wood. We used dark walnut wood stain, covered all parts of the crate, and then wiped it off after a few minutes.

With this, our crate was complete!

 

Cost  Analysis:

Raw material cost

Material	Ticket Price	Spent
1×4 lumber (202.5”)	$3.55/96”	$7.49
2×2 lumber (40”)	$3.55/96”	$1.48
1.25” screws (48)	$6.98/245 screws	$1.37
Wood stain	$6.98/8 oz.	$6.98 (overestimate because uncertain of the amount)
Total		$17.32

Labor cost

Assuming minimum wage in Texas of $7.25

Task	Time	Spent
Overhead	1 hour	$7.25
Wood preparation	4 hours	$29.00
Assembly	7 hours	$50.75
Post processing	0.5 hours
Total		$54.38

Machine time/machine hour cost

Machine hour cost can be calculated by dividing the cost of the machine by the total hours it should function, and multiplying that result by the time that the machine was in use.

The three main things used were the router, power sander, and the drill.

A Kobalt Router Table costs about $150 and should last for about 5 years. We used the router for about 3 hours, so the machine time cost was $0.01.

$150/(43830 hours) = ($0.0034/hour)×3hours = $0.010

A Black+Decker power sander costs $41.98, and is expected to last for about five years. For the five years of use, and since we used the power sander for about 1 hour, the total machine time cost was $0.001.

$210/(43830 hours) = ($0.00096/hour)×1hour = $0.00096

A Black+Decker drill costs about $85 and should last for about 3 years. We used the drill for about 7 hours, so the machine time cost was $0.02.

$85/(26280 hours) = ($0.0032/hour)×7hours = $0.023

Project total: $71.81

Overall, I really enjoyed this project and hope to build more things in the future with my new skills!