www.bikecad.ca - Curved tubes
https://www.bikecad.ca/taxonomy/term/222
enCurving tubes
https://www.bikecad.ca/curved_tubes
<div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><div class="video-container"><iframe frameborder="0" src="//www.youtube.com/embed/DyPzo-syAgg" width="800" height="480"></iframe></div><p>Tubes can be bent in BikeCAD using the Curved check box. For tubes in the front triangle, you'll find the Curved check box in the Tubing dialog box.</p><p>For chain stays you'll find two Curved check boxes in the Chain stays dialog box. One check box curves the stays in a way that is visible in the side view and the other check box curves the stays in a way that is visible in the <a title="Auxiliary view" href="http://www.bikecad.ca/stays_auxiliary_view">auxiliary view</a>.</p><p>Similar controls are found in the seat stays dialog box, with one check box for curves in the side view and another for curves in the auxiliary view. Note that if you select a wishbone seat stay you will gain an additional option for curving the seat stay in the side view.</p><p>This option is called Raked. It is meant to accommodate an approach to curving the seat stays that was used in an older version of BikeCAD. Because raked stays are controlled using a different dimensioning scheme, this may still be an option you'll want to explore for current designs.</p><p>If our design includes any <a title="Extra tubes" href="http://www.bikecad.ca/extra_tubes">extra tubes</a>, the curved check box for those is found in the Extra tubes dialog box.</p><p>When bending tubes, it's helpful to display the dimensions used to control those curves. For most curves in the side view, you'll find the dimensions in the Tubing tab of the <a title="Dimensions dialog box" href="http://www.bikecad.ca/dimensions_dialog">Dimensions dialog box</a>. Here, for example, we see all the dimensions controlling the seat stay curvature in the seat stay tab, which is a subtab of the Tubing tab. Dimensions relating to curves visible in the auxiliary views are controlled in the <strong>Stays (auxiliary view)</strong> tab. Here, for example, we see all the seat stay curve dimensions in the Seat stay subtab.</p><p>Curvature dimensions for Extra tubes are found in the Extra tubes tab.</p><p>The actual mechanics of applying bends to tubes is the same for all tubes, so I'll demonstrate on the top tube. If we apply a single bend, dimension <strong>A</strong> is the distance along the line connecting the two end points of our tube, where the deflection occurs. Dimension <strong>A</strong> can be expressed as an actual distance in mm, or as a ratio of overall tube length. Dimension <strong>B</strong> is the amount of deflection applied to the tube. Dimension <strong>B</strong> can be either positive or negative. Dimension <strong>R</strong> is the radius of the bend. If we set the radius to <strong>0mm</strong>, we'll see that dimension <strong>B</strong> goes all the way to the corner of the bend. Notice that as we increase the radius of the bend, dimension <strong>B</strong> still points to the theoretical corner of that bend. Notice also that you do not have the option to directly input the angle of the bend. However, the bend angle is one of the dimensions that you can show on the screen. If you are looking to model a bend with a particular angle, you can play with dimensions <strong>A</strong> and <strong>B</strong> until the desired angle is achieved.</p><p>If we opt to apply two bends, we gain dimension <strong>C</strong>, <strong>D</strong> and small <strong>r</strong>. Similar to <strong>A</strong>, <strong>B</strong> and <strong>R</strong>, dimension <strong>C</strong> locates the point at which the deflection occurs, dimension <strong>D</strong> defines the amount of deflection and dimension <strong>r</strong> defines the radius of the bend. Like dimension <strong>B</strong>, dimension <strong>D</strong> can be either positive or negative.</p><p>When curves are applied to any of the tubes in the front triangle, notice that the icons defining the <a title="Tube extensions" href="http://www.bikecad.ca/tube_extension">extension of the seat tube above the top tube</a> as well as the <a title="Tube extensions" href="http://www.bikecad.ca/tube_extension">extension of the head tube above and below the top tube and down tube</a> becomes locked in the mode of defining this extension as the distance along the centerline of the seat tube and head tube. The option to define the extension by a distance measured along the edge of the tube is no longer available. When modeling bends in tubes, it can be helpful to turn on the problem curves checker. For more on the use of this tool, see the video on <a title="Identifying problem curves" href="http://bikecad.ca/problem_curves">identifying problem curves in BikeCAD Pro</a>.</p></div></div></div><div class="field field-name-field-tags field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/222">Curved tubes</a></div><div class="field-item odd"><a href="/taxonomy/term/388">tube bending</a></div><div class="field-item even"><a href="/taxonomy/term/389">bent tubes</a></div><div class="field-item odd"><a href="/taxonomy/term/390">bends</a></div><div class="field-item even"><a href="/taxonomy/term/391">seat stays</a></div><div class="field-item odd"><a href="/taxonomy/term/189">chain stays</a></div><div class="field-item even"><a href="/taxonomy/term/202">seatstays</a></div><div class="field-item odd"><a href="/taxonomy/term/201">chainstays</a></div></div></div>Tue, 01 Apr 2014 04:36:20 +0000bcurry32434 at https://www.bikecad.cahttps://www.bikecad.ca/curved_tubes#commentsIdentifying problematic curves in BikeCAD Pro
https://www.bikecad.ca/problem_curves
<div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><div class="video-container"><iframe width="800" height="480" src="https://www.youtube.com/embed/qqryl4ZNvwQ" frameborder="0" allowfullscreen></iframe></div>
<p>When modeling curved tubes in BikeCAD, although you are allowed to input any amount of deflection and any value of curve radius you like. It's not always physically possible to create a tube with those properties.</p>
<p>In the example above you can tell by the artifacts extending from the down tube that we likely have a problem here.</p>
<p>A new feature in BikeCAD Pro Version 8 helps us resolve these issues. When we click on the problem curves icon, BikeCAD connects the reference points of our curved tube with dashed lines to help us visualize the geometry of our tube. It also highlights the curved sections in green or red. Red markings identify cases where there simply isn't enough room to fit the requested radius.</p>
<p>There are several possible solutions to a problem like this. For example, you could lengthen the tube. Alternatively, you could reduce the amount of deflection. Or finally, you could reduce the radius of the curve. Because there is more than one way to resolve this issue, BikeCAD leaves it up to you to change the geometry. However, once you've got something that fits, BikeCAD will display the radiused section in green.</p>
<p>Once you're satisfied with your design, you can turn off the colouration by unselecting the problem curves icon.</p></div></div></div><div class="field field-name-field-tags field-type-taxonomy-term-reference field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/taxonomy/term/222">Curved tubes</a></div><div class="field-item odd"><a href="/taxonomy/term/223">problem curves</a></div></div></div>Thu, 01 Mar 2012 06:42:44 +0000bcurry6167 at https://www.bikecad.cahttps://www.bikecad.ca/problem_curves#comments