Sketchup doesn't have a function that allows you to draw tangent lines to a circle so you have to do it the old school geometry way. Here is how.
<p>Good method but what if it was 1 3/16&quot; X 2 31/64&quot;?</p>
<p>I appreciate the video. Sketchup gets a large user-base <br>because its free, but it sucks it requires so many workarounds to achieve basic <br>results, as you demonstrate. I use it and it has its purpose. Its purpose is to <br>have reasonable 3D presentations for basic uses but it is not and cannot be <br>accurate. It is completely unusable for any purpose where 10ths, hundredths, or <br>thousands of an inch matter. </p><p>Sketchup was designed badly from its inception. At its core, <br>is flawed math. Whenever you draw a circle in Sketchup, mathematically, any <br>circle/arc is immediately translated into straight line segments. I design <br>parts and assemblies and it was very disappointing to realize it&rsquo;s impossible <br>to draw anything with accuracy using Sketchup. </p><p>It got worse when I realized it&rsquo;s hard-coded into 24 <br>segments per circle. While Sketchup does allow the user to manually change the <br>number of segments, that feature is worthless as it breaks all the internal <br>math calculations for creating faces, trimming at intersections, or, frankly, <br>anything normal in making a drawing. A user is stuck with 24 segments per 360 <br>degrees or, if you change the number of segments, you will soon learn how Sketchup <br>breaks down.</p><p>It is also broken with its hiding feature. Incessantly, I <br>hide groups or components only to discover the auto-trimming and/or auto <br>creation of faces and/or multiple other features are affected by objects that <br>are hidden or already moved. For example, I havea group in the background with arc segments <br>and not only should Sketchup not trim my newly designed lines/arcs using <br>elements from a group (its supposedly <br>designed in behavior), but I also find my elements are continuously <br>trimmed/modified by elements that are hidden.</p><p>I hope my comments don't get reflected badly on you (they <br>shouldn't). I appreciate all your effort to help with creating lines from <br>tangent to tangent. You&rsquo;re doing the only method that will work in Sketchup and <br>it is very helpful. I wish you would show users what happens when you create a <br>solid by clicking &quot;closely&quot; as you described at the beginning. Yet <br>another bad feature of Sketchup is that it does NOT ensure closed endpoints. <br>When you click closely, there is really a gap. That gap doesn't stop Sketchup <br>from allowing planes to be created (the drawing appears okay graphically), but <br>the gap does cause numerous features to break; especially those related to <br>solids. </p><p>For example, if you try to use the join or subtract features <br>they, very often, fail. I have experienced crazy bending/warping, inner <br>contours that can't have their planes deleted, or I couldn&rsquo;t join two solids simply <br>because they are broken in some undiscoverable way without a plugin helper like <br>&ldquo;Solid Helper2&rdquo;.</p><p>To be honest, Sketchup is simply not a professional software <br>product. It is impossible to design anything with accuracy and it&rsquo;s loaded with <br>buggy/limited features. </p><p>NOTE: Having said that, the free version can be very useful <br>and its very helpful to a great number of people who don't have money. It&rsquo;s <br>really not bad for something that is free. It is not worthy of the Google name.</p><p>Seriously, thanks for assisting, it does take crazy stuff <br>like your example to draw basic shapes, but knowing these type of tips/tricks <br>allows the product to be more useful. I do hate that it&rsquo;s impossible for <br>Sketchup to ever be a truly professional product (IMO) as the core engine is <br>mathematically flawed, but I do still use it knowing all its problems.</p><p>Thanks again and sorry if I want other users to be <br>wary/careful of using it. It&rsquo;s truly not a professional grade product and <br>cannot possibly be professional grade the way it mathematically works <br>under-the-hood. That is why it doesn't support simple features like snapping to <br>a tangent. The math formula that calculates a tangent requires a true arc or <br>circle's dimensions. A series of straight line segments simply don't have the <br>information required to allow that kind of feature to work. It&rsquo;s also why it <br>doesn't have a fillet option or chamfer options or any of many options that robust <br>3D/CAD systems offer. In summary, it&rsquo;s a useful toy under the right <br>circumstances and the word pro belongs nowhere near it.</p><p>Solidworks is the real deal for actual real-life production <br>purposes. For gaming or other purposes, there is a long list that are the real <br>deal, but that's not my territory. Again, for real-life professional purposes, <br>get Solidworks, or AutoCAD Inventor. Inventor LT is far superior to Sketchup <br>and costs less than Sketchup Pro.</p>
<p>Thanks. Very useful.</p>

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