The details are always the most time-consuming part of any 3D project. I've always struggled with the 'accuracy' of my 3D models. By accuracy, I mean how perfect are the bevels, angles, measurements? This is even more true when I take on a hard surface style project in Blender or Maya. Over the past year, I've nailed down a fairly quick workflow when it comes to pipe shapes. The resulting mesh has a solid thickness throughout with access to tapering via Blender's curve panel, but the mesh also retains equal spacing between other pipes. Above is a very quick result using this technique.
First, create a 'path' for your pipes. This is a simple outline created from joining planes at 90-degree angles that form the path for your pipes. Keep these super simple and position the corners where you like. In this example, I chose sharp corners and 90-degree angles but something less sharp would work just as fine.
It's important that each corner is bisected by an edge as seen below. This will ensure the bevel operations will function as intended. I created this shape by combining multiple planes and merging vertices.
Select the joining edges and with the Bevel tool, bevel them to your desired size and bevel count. **Bevels in Blender take the current scale of the object into consideration when beveling. You need to 'Apply Scale' in order for the bevel operation to work properly. Switch to OBJECT MODE, choose Object -> Apply -> Scale.
After the corner edges are beveled, you can cleanly create edge loops that flow through the whole mesh. Switch to EDGE MODE and add a single loop cut down the middle of the mesh. See how the corners are thicker than the rest? We'll take care of that.
Select the new loop cut and choose 'Mesh' -> 'Separate' -> 'Selection' to create an object just containing the selected edge. Hide or delete the original path mesh.
The result should be simply edges with no faces, just edges and vertices.
We still have a couple more modeling actions before we can turn this into a pipe. This is where the detail talk from earlier comes in handy, especially if we want several equidistant pipes. Extrude the pipes in the Y direction (Z in Maya). This may seem a little strange now, but it'll make sense in a few more steps.
Once you've extruded the edge, switch to EDIT FACE MODE and select every face on the mesh. Then in your tool pallet, click and hold on to the extrude tool until the second tool panel pops up, choose 'EXTRUDE ALONG NORMALS' with every face selected. If your object doesn't look right or is kind of exploding in certain corners, it's probably because your normals are inverted on some of your faces. Undo the extrude then select every face again, choose Mesh> Normals> Recalculate Outside to get consistent normals. Attempt the extrude along normals operation again.
Now that the extrude by normals operation gives us clean angles, we can now delete all interior loops and the mesh's thickness. Our goal is to return to the single-axis mesh we have a little bit ago, but this time with clean angles.
Choose the Loop Cut tool again and add as many loops as you want for piping. Make sure there is enough space to account for your pipe thickness. I added three cuts. After cutting your loops, select the exterior and interior loops ONLY. Don't select the cap edges.
Now separate by selection again by going to Mesh> Separate> Selection. This left me with five copies of my edges.
Now we're going to convert this to a curve by switching to OBJECT MODE and going to Object> Convert> Curve. Your edges are now curves, if you go into edit mode you can see the control points. Go to the Properties Panel and select the Curve tab. There you can modify the Depth and Resolution settings of the Bevel twirl down to achieve a pipe look. Play with the options, offset and extrude can do some really neat stuff that could help with animation or any kind of growing effect.
Once you're satisfied with your properties, back in OBJECT MODE select Oject> Convert> Mesh to convert the pipes back into geometry for more detail modeling.
Hope this helps you tackle some complex pipe layouts. I find getting clean base shapes can be tough, but once you have that foundation adding small details becomes much easier. If you like these tutorials and want to support my work you can buy me a coffee: https://ko-fi.com/bruceevans or download my toolset from Artstation or Gumroad. Cheers!