Most parts are designed on a plane. A 2D sketch, an extrusion\u2014we\u2019re making progress. The problem arises when the geometry extends in three directions at once: a tubular frame, a pipe run, or a wireframe structure whose segments change orientation. In such cases, stacking 2D sketches on reference planes quickly becomes unmanageable. That\u2019s what 3D sketching is for.<\/p>\n
A 2D sketch exists on a plane. Everything you draw remains flat on that plane. A 3D sketch exists in space: each segment can point in any direction, without creating a plane each time.<\/p>\n
To start one: Insert > 3D Sketch. The Tab key switches the active workplane between XY, YZ, and ZX as you draw. The marker that follows the cursor indicates which plane you\u2019re drawing in. This is what\u2019s confusing at first: you think you\u2019re drawing on a flat surface, but you\u2019re actually drawing in depth. Look at the marker, not the view.<\/p>\n
A 3D sketch cannot be extruded like a closed 2D profile unless the outline in question is planar. If you try to extrude a path that winds through space, SOLIDWORKS will either reject it or only accept a portion of it. There are two valid methods, depending on your needs.<\/p>\n
For a structure made of beams, tubes, or profiles, the 3D sketch serves as the framework. You draw the entire path in a single 3D sketch, then apply a mechanically welded element (Insert > Mechanically Welded > Structural Element). SOLIDWORKS places the selected profile along each segment and handles the miter cuts at the intersections. The entire structure is created in one go, not segment by segment.<\/p>\n
For cable, conduit, or pipe runs, the 3D sketch defines the path of a sweep. A circular profile\u2014the 3D path\u2014is defined, and the sweep follows this path even if it changes planes three times.<\/p>\n
If you really need several extruded bosses oriented in different directions, don't mess everything up in a 3D sketch. Create the 3D sketch as a geometric reference (points, axes, construction edges), then base your extrusions on planes constructed from these references. This keeps your control clean: move a point in the 3D sketch, and all the extrusions follow.<\/p>\n
My advice: For a structural framework or a frame, don\u2019t create extrusions manually one by one. A 3D sketch of the framework combined with mechanically welded components is faster to create, easier to modify, and the bill of materials generates automatically. Save individual extrusions for details that the mechanically welded parts don\u2019t cover.<\/p>\n
Constrain the 3D sketch from the start. An underconstrained 3D sketch deforms unpredictably when you add a dimension. Fix the starting points, and set constraints along the X, Y, or Z axes on the segments that must remain straight.<\/p>\n
Use blocks if the same spatial pattern recurs. You create it once, then reuse it. And name your 3D sketches in the tree: on a complex wireframe part, \u201c3D Sketch 12\u201d won\u2019t mean anything to you in six months.<\/p>\n
Need help with your SOLIDWORKS design methods? Ohmycad trains and equips engineering firms<\/a> on these topics in everyday life.<\/p>\n As soon as the geometry branches out in multiple directions at once\u2014a tubular frame, a pipe run, a wireframe structure\u2014the 2D sketch remains simpler when viewed on a single plane.<\/p>\n Insert > 3D Sketch. As you draw, the Tab key toggles the active workplane between XY, YZ, and ZX, and the reference line that follows the cursor indicates which plane you are drawing in.<\/p>\n Not like a closed 2D profile, unless the contour in question is planar. For a path that winds through space, a mechanically welded element (for a structure) or a sweep (for a cable or pipe run) is used instead.<\/p>\n Draw the entire path in a single 3D sketch, then apply a mechanically welded structural element (Insert > Mechanically Welded > Structural Element). SOLIDWORKS places the profile along each segment and handles miter cuts at the intersections.<\/p>\n Constrain it from the start: set the starting points and create constraints along the X, Y, or Z axes on the segments that must remain straight. A 3D sketch with insufficient constraints moves unpredictably as soon as a dimension is added.<\/p>\n In the same series:<\/strong> Symmetries in SOLIDWORKS<\/a> and sheet metal tables<\/a>.<\/p>","protected":false},"excerpt":{"rendered":" Quand et comment utiliser les esquisses 3D de SOLIDWORKS pour construire des structures et extrusions orient\u00e9es dans l’espace, sans se battre avec les plans.<\/p>","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_breakdance_hide_in_design_set":false,"_breakdance_tags":"","footnotes":""},"categories":[498],"tags":[],"class_list":["post-117561","post","type-post","status-publish","format-standard","hentry","category-tutoriels-astuces"],"acf":[],"_links":{"self":[{"href":"https:\/\/ohmycad.com\/en\/wp-json\/wp\/v2\/posts\/117561","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ohmycad.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ohmycad.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ohmycad.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/ohmycad.com\/en\/wp-json\/wp\/v2\/comments?post=117561"}],"version-history":[{"count":0,"href":"https:\/\/ohmycad.com\/en\/wp-json\/wp\/v2\/posts\/117561\/revisions"}],"wp:attachment":[{"href":"https:\/\/ohmycad.com\/en\/wp-json\/wp\/v2\/media?parent=117561"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ohmycad.com\/en\/wp-json\/wp\/v2\/categories?post=117561"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ohmycad.com\/en\/wp-json\/wp\/v2\/tags?post=117561"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Frequently asked Questions<\/h2>\n
When should you use a 3D sketch instead of a 2D sketch?<\/h3>\n
How do I start a 3D sketch in SOLIDWORKS?<\/h3>\n
Can you extrude a 3D sketch?<\/h3>\n
How do you create a tubular frame from a 3D sketch?<\/h3>\n
How can you prevent a 3D sketch from becoming distorted?<\/h3>\n