Thanks Griz! I really appreciate the feedback and especially the advice - I will give card scrapers a try. And of course you are more than welcome to steal the design details - you can see I did the same from the FWW article I referenced.

The 3D program I used when I designed this (you can see the date stamp in my screenshot - 2017) was called Sketchup. It was by Microsoft and was a free program at the time... I don't think it is anymore but haven't checked recently.

Since I haven't been much in the basement this past year+ other than for my Christmas build (the Warthog), I haven't been designing much. But start with Sketchup and see what else is out there. Some are easier to learn and use, others not so much. Sketchup was in the middle for ease-of-use.

I just looked at my list of software and it looks like I downloaded Autodesk Fusion 360. But I have not taken it for a spin - and I can't tell you why I picked it... I must have looked at some online reviews of software and picked the "best" free 3D software... This would have been late 2018 or early 2019 when I got frustrated with Sketchup... sorry I'm not being more useful!!

SD