Step 8: Projectile Arm 1

So, luckily, I have more pictures for this arm... So you can at least get an idea of how to make the simple projectile arm... For Arm 2 you'll have to put up with my drawings...

This arm is made up of three square lashings and one tripod lashing.

Image 2 gives you an idea of the construction before being lashed up

First you want to start by making a sorta crucifix shape like in picture 3. Then by adding your two side pieces (that make up the support for the arm) using, you guessed it ... SQUARE LASHINGS you should get a ...fork shape.. Like in picture 4

Now, using the tripod lashing that you saw in the last step... lash up the top end, to make the shape of image 5!

<p>Any chance this could be built using the knots Cub Scouts are required to learn?? I'm looking for a fun activity to use for our boys to practice making their knots, especially my wolves and webelos. Not sure what knots my webelos need to work on, but my wolves need to learn the square knot.</p>
Well itninvolves clove hitches and square lashings so i would assume it fits your badge requirement. However workingbon such a small scale might be difficult for your cubs.ntry broommpoles and stringnor rope. Makes for a good group activity<br>
that really didnt make any sense, but at least i already know how to tie a knot lol. Great job by the way. i hope you dont mind but im going to use this for a school project.
Aslong as you send me a picture of how well it turned out :)
well my teacher made me take it apart because some of the dowels were his but im going to make a new one when summer starts <br>
well bbq sticks and cotton works really well :)
I love the word &quot;trebuchet.&quot; I want a bumper sticker that reads: <br><br>WHEN TREBUCHETS ARE OUTLAWED, ONLY OUTLAWS WILL HAVE TREBUCHETS!
me and my scout group once made a &quot;full size&quot; (+/- 2 meters high) Trebuchet, it shot 70 meters or about 230 feet :D it was so cool but unfortunately it broke the first or second time we shot it, and we haven't rebuild it xD
We once built two trebuchets and fired water balloons at one an othr... that was good fun
Amazingly over engineered - we do this with elastic bands :) I've just been doing some full scale projects, working my group up to building a full size pioneering trebuchet.
In all honesty I loathe green garden stick/elastic band pioneering... I don't think it teaches the kids anything.... when I build /pioneer with my scouts, we use nothing smaller than broom staves, so they can lash and knot... I don't see the point of dooing the activity otherwise.... Elastic band pioneering perhaps is good for beavers and younger cubs... but i dont think it can replace the knot work...
Nice Clean lashings. What is the overall size of your scale model? also what size of twine have you found works well with this size of project?
To be honest on thease small scales, embroidery cotton works just as well as what I used... not sure about the sizeing of the yarn... It's similar strand width to that of embroidery silk, I haven't a clue where I got it from... But I tell you what would work really well, is the waxed cordage you can get from craft shops such as Hobby Craft (in the UK)<br /> <br /> If its any help... the reel the yarn is on says:sylko Perle' 250m....sh.736 no.5 bey(think thats the colour)<br /> <br /> the smaller trebuchets are about 3 or 4 inches high... I can't put my hand to a ruller at the moment, but I hope that helps :)<br />
Hmm apparently this I'ble has been Featured... but no funky banner yet.... All in good time I imagine....but well... YAY me ;)<br />

About This Instructable




Bio: I'm an un-repentant mess creator... I'll turn my hand to anything and providing i get my fingers back... I'm happy.
More by Biggsy:Scout Project: Campfire Cakes (Cakes cooked in an orange) My Robot conversion... Monkey to Man Cardboard Props: How to make a 1950's type Press Camera 
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