This list of materials is copied directly from my science fair project. It includes what I used at the time. The lumber list is really long, but I think I bought somewhere around 20 8' long 2 X 4s, I'm not sure... This still does not include the 2 X 6 pieces or any other pieces of plywood. I would still recommend that you read through the list, and buy the lumber as you need it to avoid wasting wood. Buy 15 2 X 4s to start off with, then buy more later. Also, if I mention anything else in the instructable that I didn't mention here, let me know.Materials
2 segments of 6 ft. (1.8288 m) long 2 X 4
These are the horizontal beams that are used as the track.
2 segments of 6 ft. (1.8288 m) long 1 X 6
Long sides of the base
2 segments of 2 ft (0.6096 m) 1 X 6
Short sides of the base
*It would be better if the two previous 1 X 6 pieces were 2 X 6, I'll explain later.
2 segments of 6 ft., 2 in. (1.8796 m) long 2 X 4
2 segments of 5 ft., 10 in (1.7272 m) long 2 X 4
The two previous segments are diagonal supports. Cut at least 3 inches longer unless you are very good at cutting angles accurately (A miter saw would help)\
2 segments of 8 ft (2.4384 m) long 2 X 4
These will be the drop channels
*look at the last step: improvements. This may need to be changed.
8 segments of 3 ft., 6 in (1.0668 m) long 2 X 4
Main track supports
look in improvements, may need to be changed
4 segments of 4 ft., 5 in. (1.3462 m) long 2 X 4
These are the pieces of wood directly on either side of the drop channels.
2 segments of 2 ft., 11 in. (0.889 m) long 2 X 6
3 segments of 3 ft (0.9144 m) long 2 X 6
More diagonal supports. These Are not included in the instructable because I did not think they were necessary. I might include them later. If you really want to include them, they should also be cut about 3 inches longer, until you know what to cut.
2 segments of 1 ft., 0.5 in. (0.3175 m) long 2 X 4
2 segments of 2 ft. (0.6096 m) long 2 X 4
extra lateral support
4 segments of 1 ft., 5 in. (0.4318 m) long 2 X 4
4 segments of 1 ft., 5 in. (0.4318 m) long 2 X 6
diagonal supports, lateral and track-supporting
2 segments of 3 ft. (0.9144 m) long 2 X 4
6 segments of 2 ft., 5 in. (0.7112 m) long 2 X 4
These make up the short arm
May need to be shortened, look at improvements
2 rectangles of 3/4" in. (2.54 cm.) thick plywood, 2 ft., 5 in. X 3.5 in. (0.7112 X 0.0889 m)
Plywood also included in the arm
1 segment of 7 ft. long 2 X 4
the arm itself
2 rectangles of 3/4 inch (1.905 cm) thick wood, 1.5 in. by 2 in (0.381 X 0.0508 m)
The two bits at the open top of the cut channel..keeps the drop channel from "opening"
*look at the last step, improvements. This may need to be changed
4 rectangles of 3/4 inch (1.905 cm) thick wood 9.5 X 5.5 in (0.2413 X 0.1397 m)
4 rectangles of 3/4 inch (1.905 cm) thick wood 9 X 4 in. (0.2286 X 0.1016 m)
4 rectangles of 3/4 inch (1.905 cm) thick wood 9.5 X 9 in. (0.2413 X 0.2286m)
Threee previous sections are for the counterweight boxes. This might change depending on your weights setup. This is what fit for me. Also, 1 inch thick wood would would be stronger.Hardware
about 250 2.5 in. (6.35 cm.) wood screws, phillips head drive, #8
I would get more in case some of their heads strip...
if you buy pt lumber make sure they are approved for use in it..
8 .5 in. (1.27 cm) wood screws, phillips head drive, # 8
16 1.5 in (3.81 cm.) wood screws, phillips head drive, #8
3 ft. (0.9144 m.) long 5/8 in. (1.5875 cm.) diameter threaded rod, coarse thread
NEEDS TO BE MADE THICKER: LOOK AT IMPROVEMENTS
2 segments of 2 ft. (0.6096 m.) long 5/8 in. (1.5875 cm.) diameter threaded rod, coarse thread
May need to be made thicker
20 5/8 in. (1.5875 cm.) nuts, coarse thread
for the threaded rod
24 5/8 in. (1.5875 cm.) washers
again for the threaded rod
10 1/4 in. (0.635 cm) diameter, 5.5 in. (15.24 cm.) long carriage bolts
For the arm assembly
6 1/4 in. (0.635 cm) bolts, matching thread
for the carriage bolts
6 1/4 in. (0.635 cm) washers, matching carriage bolts
for the carriage bolts
3/8” X 4” eye bolt (Including bolts)
8 matching cut washers
these will be used in the trigger
2 1/2” X 10” eye bolts
these are the trigger pinsWheels, weights
3 3 in. X 1.5 in. (7.62 X 3.81 cm) diameter wheels, 5/8 id bearing load rating of 200 lbs (90.71 kilos) or more
May need to be hanged if the diameter of the threaded rod is changed
excellent site for cheap, strong wheels http://www.thecasterguy.com/
2 hand weights, 10 lbs (4.54 kilos)*
2 hand weights, 8 lbs (3.63 kilos)*
*must be able to fit inside counterweight boxesSling
Approx. 50 ft. (15.34 m) of 3/16” (0.47625 cm) braided polyester cord
The sling lines, I bough 50 ft because i needed to cut the right lengths for each ratio, you probably wont really need more than 15 ft.
Approx 25 ft. (7.62 m)1/2” braided nylon rope
(This is actually for the trigger)
15 in. X 6.5 in (38.1 X 16.51 cm.) denim fabric
for the sling
Just find a pair of old jeans
Approx. 10 ft. (3.048 m ) of gorilla tape
for the sling
1 keychain ring
A solid metal ring of any kind would work better.
One thick nail.
This is the pin.
I don't know what gauge mine was, I found it in the trash Buy one that is at least 4 inches. The thicker the better to prevent it from bending. You should also cut off the head if you keep getting downward throws no matter how you adjust it.
If you want a better pin system, look at the turnbuckle pin system here.
(third picture on the right) RLT industries trebuchet.com
hacksaw if you don't have a METAL CUTTING BLADE FOR YOUR JIGSAW,
jigsaw the one I used here
circular saw (The one I used here) OR miter saw AND table saw
you need to miter, rip, and crosscut.
drill (The one I used here
came in a kit here
) with a varied drill bit set, for pilot holes, etc. One drill bit MUST be the size of your threaded rod (Mine was 5/8", it should be thicker) Ideally, the drill bit would be a foot long, or 6 inches, so that the holes in the arm don't become misaligned. I'll explain later...
also screwdriver bit driving in your screws.
coping saw and orbital sander (The one I used here
Socket wrench for your threaded rod
...I'm kinda adding these as I think of them..
Tape measure, ruler
I think that's it
OK onto step 1