Final product review

Reflection.

The crossbow is an example of energy transfer, a transfer from elastic energy to kinetic energy. Its starts when you pull the string back to the latch. Then the energy u used to pull the string back turns into elastic potential energy and is stored in the bamboo part of the bow. After that, when the trigger is pushed down, the string will be lifted up from the latch. Due to the elastic energy stored in the bow, the bamboo would like to extend bringing the string forward. This movement pushes the projectile forward, turning the elastic energy stored into kinetic, launching the projectile forward.

Successful areas

The body of the crossbow came together very well, we were lucky to have such a hard sturdy wood to use it on.

The bamboo also went on without a hitch, for the most part.

Except for the body nothing had to be remade and we had time to sand everything down so it is more smooth.

The string is my favorite part, we found the best possible string for it and the knot we chose is really simple and effective, meaning we could remake them really well. We only had to remake the string 2 times to get the correct measurement but that’s not a big problem.

What could be improved

Due to time constraints. We didn’t have time to completely polish the crossbow. I would have liked it more if we managed to sand it a bit more using finer sand.

My biggest regret was not covering the crossbow with a layer of oil to give it a good color and waterproof it. Adding the oil would have better protected the wood from weathering away.

Impact on the environment.

This is made of wood and bamboo and metal. Except for the rope, all of the other ones can be reused or recycled. So there won’t have a very large environmental damage. However, a crossbow was used as a weapon in ancient days, and having one around might harm other people. However, the speed of this crossbow shouldn’t be strong enough to seriously injure a person. But still, keep it out of the child’s reach and make sure to wear eye protection while using it.

Potential client.

A  potential client might be a person who is interested in bows and projectile launchers. Also with less power, this might be a nice toy similar to the nerf gun.

Or if you live in medieval times and need a simple yet effective long-range projectile launcher in order to stop an invading army in its tracks, while also not having explicit training to use a longbow.

Crossbow plan

the cross bow will be consisted of mostly 2 parts them being the body of the crossbow and the bow part, with some small parts such as the trigger.

The body

the body will be made by using a 2 by 4 (like a wooden beam). the beam will then be measured and put through a band saw get the correct shape (which is around 75cm by 3cm by 8.5cm). before sanding down using the circular sander to smoothen the and have a smoother grip. if there is more time use a handheld sander to sand down the entire thing to make sure all of it is smooth and you wont get a splinter.

The bow

the bow will be a piece of bamboo that will be around 108cm long. it would be simple but would require the use of the small round saw I think to cut the corners on the ends of it to make the rope stay.

The trigger

the trigger would simply be a piece of metal or something hard on the latch so when the rope is pulled back and the rope is on the wood all we need to do it to flick the metal up and would release the string.

Connecting the body and the bow

this would be slightly tricky, however it can be done by cutting a square out of the body and putting the bamboo inside the square before filling up the square with wood and glue to hold it in place.

day 1 planning

make the plan

day 2 making

make the body

day 3 making

put bamboo onto the body

day 4 make groove and attach sting and trigger.

1. What is your biggest take away from 6th-grade science?       my biggest takeaway from 6th-grade science is analyzing data
2. If you were to write your own comment on the report card, what would you say?  How confident do you feel in making models in science, analyzing data, and constructing scientific explanations?                  for models I feel not very confident but analyzing data i am pretty confident and for constructing scientific explanations I don’t feel very confident.
3. What would you like to work on for next year in science?               i am interested to learn anything.

Me and Cormac made a water filter and guess what, it did not work as planned but after we modified it worked okay it looked like pee.