{"id":981,"date":"2009-11-15T22:41:41","date_gmt":"2009-11-16T04:41:41","guid":{"rendered":"http:\/\/gregsowell.com\/?p=981"},"modified":"2009-11-15T23:42:57","modified_gmt":"2009-11-16T05:42:57","slug":"desktop-catapult","status":"publish","type":"post","link":"https:\/\/gregsowell.com\/?p=981","title":{"rendered":"Desktop Catapult"},"content":{"rendered":"<p>So, I saw some homemade catapults a while back and figured I would try my hand at making one.  Here&#8217;s the prototype.  BTW, the video is at the end!<\/p>\n<p>Materials:<\/p>\n<ul>\n<li>About 2 feet of 1X4.  I picked up a 10&#8242; sheet for $1.81.  I used pine since this was a prototype, for the real deal, I would use a hard wood.<\/li>\n<li>8 screws.<\/li>\n<li>1 dowel rod.  I got an oak rod for $.99.<\/li>\n<li>Some cotton twine.<\/li>\n<li>A saw, drill, screw driver and proper safety equipment.<\/li>\n<li>Optional wood glue.<\/li>\n<li>Optional 4 year old assistant \ud83d\ude09<\/li>\n<\/ul>\n<p>I started by cutting a 11&#8243; piece of the 1X4 for the base.  Then I cut a 2&#8243; piece 10&#8243; long for the launch arm.  I then cut two 2X2 squares to hold the launch pin.  I cut a 1X2 piece for the launch pin.  I cut two triangles just using my square, so all angles are just simple 45s.<\/p>\n<figure id=\"attachment_984\" aria-describedby=\"caption-attachment-984\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-984\" title=\"DSC05407\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05406.jpg\" alt=\"All the bits cut and supplies\" width=\"640\" height=\"480\" \/><figcaption id=\"caption-attachment-984\" class=\"wp-caption-text\">Roughly what it will look like<\/figcaption><\/figure>\n<figure id=\"attachment_984\" aria-describedby=\"caption-attachment-984\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-984\" title=\"DSC05407\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05407.jpg\" alt=\"Roughly what it will look like\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05407.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05407-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-984\" class=\"wp-caption-text\">Roughly what it will look like<\/figcaption><\/figure>\n<img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-985\" title=\"DSC05409\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05409.jpg\" alt=\"Marking the triangle holes down the center.  Every 1\"\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05409.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05409-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-986\" title=\"DSC05410\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05410.jpg\" alt=\"\"I marked it!\"\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05410.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05410-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/>\n<figure id=\"attachment_987\" aria-describedby=\"caption-attachment-987\" style=\"width: 480px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-987\" title=\"DSC05413\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05413.jpg\" alt=\"Setting the drill bit\" width=\"480\" height=\"640\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05413.jpg 480w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05413-225x300.jpg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption id=\"caption-attachment-987\" class=\"wp-caption-text\">Setting the drill bit<\/figcaption><\/figure>\n<figure id=\"attachment_989\" aria-describedby=\"caption-attachment-989\" style=\"width: 480px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-989\" title=\"DSC05420\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05420.jpg\" alt=\"Safety 1st ;)\" width=\"480\" height=\"640\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05420.jpg 480w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05420-225x300.jpg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption id=\"caption-attachment-989\" class=\"wp-caption-text\">Safety 1st \ud83d\ude09<\/figcaption><\/figure>\n<figure id=\"attachment_990\" aria-describedby=\"caption-attachment-990\" style=\"width: 480px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-990\" title=\"DSC05423\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05423.jpg\" alt=\"Never too early to get them started\" width=\"480\" height=\"640\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05423.jpg 480w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05423-225x300.jpg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption id=\"caption-attachment-990\" class=\"wp-caption-text\">Never too early to get them started<\/figcaption><\/figure>\n<figure id=\"attachment_991\" aria-describedby=\"caption-attachment-991\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-991\" title=\"DSC05426\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05426.jpg\" alt=\"The triangles drilled\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05426.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05426-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-991\" class=\"wp-caption-text\">The triangles drilled<\/figcaption><\/figure>\n<figure id=\"attachment_992\" aria-describedby=\"caption-attachment-992\" style=\"width: 480px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-992\" title=\"DSC05430\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05430.jpg\" alt=\"Predrilling the holes for our triagles\" width=\"480\" height=\"640\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05430.jpg 480w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05430-225x300.jpg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption id=\"caption-attachment-992\" class=\"wp-caption-text\">Predrilling the holes for our triagles<\/figcaption><\/figure>\n<figure id=\"attachment_993\" aria-describedby=\"caption-attachment-993\" style=\"width: 480px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-993\" title=\"DSC05434\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05434.jpg\" alt=\"The triangles mounted\" width=\"480\" height=\"640\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05434.jpg 480w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05434-225x300.jpg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption id=\"caption-attachment-993\" class=\"wp-caption-text\">The triangles mounted<\/figcaption><\/figure>\n<figure id=\"attachment_994\" aria-describedby=\"caption-attachment-994\" style=\"width: 480px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-994\" title=\"DSC05435\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05435.jpg\" alt=\"Bottom view so far\" width=\"480\" height=\"640\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05435.jpg 480w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05435-225x300.jpg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption id=\"caption-attachment-994\" class=\"wp-caption-text\">Bottom view so far<\/figcaption><\/figure>\n<figure id=\"attachment_995\" aria-describedby=\"caption-attachment-995\" style=\"width: 480px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-995\" title=\"DSC05436\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05436.jpg\" alt=\"Predrilling lock holders\" width=\"480\" height=\"640\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05436.jpg 480w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05436-225x300.jpg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption id=\"caption-attachment-995\" class=\"wp-caption-text\">Predrilling lock holders<\/figcaption><\/figure>\n<figure id=\"attachment_996\" aria-describedby=\"caption-attachment-996\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-996\" title=\"DSC05439\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05439.jpg\" alt=\"Lock drilled and marked.  Sitting on lock holders.\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05439.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05439-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-996\" class=\"wp-caption-text\">Lock drilled and marked.  Sitting on lock holders.<\/figcaption><\/figure>\n<figure id=\"attachment_997\" aria-describedby=\"caption-attachment-997\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-997\" title=\"DSC05440\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05440.jpg\" alt=\"Lock cut\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05440.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05440-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-997\" class=\"wp-caption-text\">Lock cut<\/figcaption><\/figure>\n<figure id=\"attachment_999\" aria-describedby=\"caption-attachment-999\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-999\" title=\"DSC05441\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05441.jpg\" alt=\"Lock with dowel inserted.  Just about to cut the dowel off clean.\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05441.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05441-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-999\" class=\"wp-caption-text\">Lock with dowel inserted.  Just about to cut the dowel off clean.<\/figcaption><\/figure>\n<figure id=\"attachment_1000\" aria-describedby=\"caption-attachment-1000\" style=\"width: 480px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1000\" title=\"DSC05442\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05442.jpg\" alt=\"Lock complete\" width=\"480\" height=\"640\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05442.jpg 480w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05442-225x300.jpg 225w\" sizes=\"auto, (max-width: 480px) 100vw, 480px\" \/><figcaption id=\"caption-attachment-1000\" class=\"wp-caption-text\">Lock complete<\/figcaption><\/figure>\n<figure id=\"attachment_1001\" aria-describedby=\"caption-attachment-1001\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1001\" title=\"DSC05443\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05443.jpg\" alt=\"Dry run of how launch arm will fit\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05443.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05443-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-1001\" class=\"wp-caption-text\">Dry run of how launch arm will fit<\/figcaption><\/figure>\n<figure id=\"attachment_1002\" aria-describedby=\"caption-attachment-1002\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1002\" title=\"DSC05444\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05444.jpg\" alt=\"Drilled small hole in 1.5\" dowel\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05444.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05444-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-1002\" class=\"wp-caption-text\">Drilled small hole in 1.5<\/figcaption><\/figure>\n<figure id=\"attachment_1003\" aria-describedby=\"caption-attachment-1003\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1003\" title=\"DSC05445\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05445.jpg\" alt=\"Twine run from one dowel through the holes - either side of launch arm - through holes and into the last drilled dowel.\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05445.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05445-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-1003\" class=\"wp-caption-text\">Twine run from one dowel through the holes - either side of launch arm - through holes and into the last drilled dowel.<\/figcaption><\/figure>\n<figure id=\"attachment_1004\" aria-describedby=\"caption-attachment-1004\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1004\" title=\"DSC05446\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05446.jpg\" alt=\"Another view of twine around launch arm\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05446.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05446-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-1004\" class=\"wp-caption-text\">Another view of twine around launch arm<\/figcaption><\/figure>\n<figure id=\"attachment_1006\" aria-describedby=\"caption-attachment-1006\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1006\" title=\"DSC05451\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05451.jpg\" alt=\"In the launched position\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05451.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05451-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-1006\" class=\"wp-caption-text\">In the launched position<\/figcaption><\/figure>\n<figure id=\"attachment_1007\" aria-describedby=\"caption-attachment-1007\" style=\"width: 640px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-1007\" title=\"DSC05452\" src=\"http:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05452.jpg\" alt=\"In the locked position, ready to launch\" width=\"640\" height=\"480\" srcset=\"https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05452.jpg 640w, https:\/\/gregsowell.com\/wp-content\/uploads\/2009\/11\/DSC05452-300x225.jpg 300w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><figcaption id=\"caption-attachment-1007\" class=\"wp-caption-text\">In the locked position, ready to launch<\/figcaption><\/figure>\n<p>So, the way it works is to wind both of the dowels forward.  This streches the twine which inturn puts pressure on the launch arm and forces it forward.  Once you get it sufficiently tight, you pull the launch arm back and lock it with the lock pin.  You put some object in the little launch cup that I boared into the launch arm, then pull the launch pin back.  If it doesn&#8217;t go quite as far as you would like, just wind the dowels farther forward.<\/p>\n<p>I noticed that my triangles are starting to lean in from how tight I have the dowels twisted.  I&#8217;m going to put a little block below the launch arm on the triangles to hold them apart, I&#8217;ll update the post when I do.<\/p>\n<p>As always, thanks for reading, and please leave me some comments.<\/p>\n<p>The Video below is my 4 year old launching a lizard =)<\/p>\n<p><object width=\"425\" height=\"344\"><param name=\"movie\" value=\"http:\/\/www.youtube.com\/v\/pSnQdQncPeQ&#038;hl=en_US&#038;fs=1&#038;rel=0\"><\/param><param name=\"allowFullScreen\" value=\"true\"><\/param><param name=\"allowscriptaccess\" value=\"always\"><\/param><embed src=\"http:\/\/www.youtube.com\/v\/pSnQdQncPeQ&#038;hl=en_US&#038;fs=1&#038;rel=0\" type=\"application\/x-shockwave-flash\" allowscriptaccess=\"always\" allowfullscreen=\"true\" width=\"425\" height=\"344\"><\/embed><\/object><\/p>\n","protected":false},"excerpt":{"rendered":"<p>So, I saw some homemade catapults a while back and figured I would try my hand at making one. Here&#8217;s the prototype. BTW, the\u2026<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[28],"tags":[],"class_list":["post-981","post","type-post","status-publish","format-standard","hentry","category-fun"],"_links":{"self":[{"href":"https:\/\/gregsowell.com\/index.php?rest_route=\/wp\/v2\/posts\/981","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gregsowell.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gregsowell.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gregsowell.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/gregsowell.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=981"}],"version-history":[{"count":18,"href":"https:\/\/gregsowell.com\/index.php?rest_route=\/wp\/v2\/posts\/981\/revisions"}],"predecessor-version":[{"id":1012,"href":"https:\/\/gregsowell.com\/index.php?rest_route=\/wp\/v2\/posts\/981\/revisions\/1012"}],"wp:attachment":[{"href":"https:\/\/gregsowell.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=981"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gregsowell.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=981"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gregsowell.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=981"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}