The problem you are having happens because you haven't redirected the edge flow around the extrusion, and correctly boundary looped it off from the surrounding topology. So I would start with more segments in my cylinder (64 to better establish curvature) and then I'd select the polys I want to extrude, inner extrude them once to divert the edge flow around it, then do the extrude, and use the 'borrowed edge' technique to add the vertical control edges to the extruded block, and above and below it to ring fence it off from the rest of it. Then, because of my increased initial subdivision I can slightly slide the outer loops outwards to the edge of the block to nicely solidify those edges without disrupting the curvature of the cylinder too much. I also did double control loops vertically, just to get it that little bit tighter.   Like so...          CBR  

Looks right. Which technique did you use?

Trying to create a simple missile with fin. I've included project in Studio 18 if interested in looking closer. I made 4 attempts. Attempt 3 is probably my closest to success (shown in image), but you can see there is still a bump or pinching. I think its due to the 4-sided triangles, but I can't figure out a better poly layout to smooth things. Attempt 4, which is not shown, I tried creating the fin on an edge. That had a similar result to number 3. I know this has to do with poly layout, but I'm struggling to find the solution. Would appreciate any guidance. Thanks missle_01.c4d

I use XRefs to load my characters and core models into my scene. I've now got a scene file where all of the XRefs are frozen: all the options, like "reload" are grayed-out. Even the XRef object's coordinates are uneditable.   I've experienced this twice before. First, I discovered that XRefs loaded using a relative path can lock up like this. The solution was to keyframe some property on the XRef (like its position), and it would "unlock" it, allowing you to edit the "options" and switch to absolute file path.     Only once since then have I had an XRef lock up like this, and restrarting C4D fixed it.  I've restarted C4D, restarted my computer... and I can't do anything to the xrefs in this scene file.    Anyone know of a way to force an update or refresh, or something?

As they say on kids TV - here's one I made earlier    

Jed,   That works perfectly.    I was close to this one of my attempts, but couldnt get it.   Right, I was using the Degree node to convert the radians. I think my problem was using a range mapper at the beginning, which was restricting it to only the first rotation and also not using the Math:Modulo.   Thanks, really appreciate you taking the time to look at it!    

Not sure where the 44 fits in, but I think this file does what you want ie it turns the 2nd wheel by 44 degs from 90% > 100 %. There's a readout for the 2 rots, and a user data control to turn 1st wheel. Remember that XPresso uses radians not degrees.   turn44.c4d

There´s a odometer inside Content Browser. Simply type into search field in Content Browser "odometer". Not sure if it´s what you want to achieve, but you can check how it´s made...