I may take on some work down the road, but I would have to really have things down before I would be willing to make stuff for others. That will take some time...
Winston Moy has a pretty
good series of videos about his first attempt at (small scale) mass production with a CNC.
... by chance would you consider doing custom work for fellow model rocket enthusiast? Could be a profitable little cottage business.
I won't speak for other tool owners here, and I certainly don't want to discourage you from commissioning custom work, but I can tell you why I haven't given it any serious consideration.
The CNC provides two advantages; precision and automation. Its the automation part that might make it profitable.
Setting up a job on the CNC can be pretty time consuming. Between modeling and setting up the tool-paths, I spent more than 2 hours on the centering rings pictured upthread. Prepping the tool took about 20 minutes. Then about 30 minutes to complete the cut and get the pieces off the tool. That was a lot of overhead for a very a simple job; single sided, and all cut with a single endmill.
It was my whole morning getting the first set made. If there was a market for Estes PSII 2" to PSII 2.5" centering rings (the most "custom" thing in that job), I could turn out a lot of them in a day. If I was only going to sell the few that I cut yesterday -- between my time, materials, and wear-and-tear on the tool -- they'd be prohibitively expensive.
I am still learning how to do this, but right now I could model a set of airfoil fins from scratch in one or two hours. Setting up the tool paths might be another hour. Cutting would be 30 minutes to 2 hours per side, depending on the size and number of parts -- and would require some number of manual end mill changes.
The Shapeoko XL has 33" by 17" of useable cutting area (which is a lot for a home CNC) which limits the number of multiples I could produce in one pass.
For example: I cut two simultaneous sets of the fins on the orange BT300 rocket you can see in the corner of the image I posted
here. I was able to cut those double-sided, which saved space on the wasteboard -- but meant manually flipping the workpiece and repeating about half of the cutting operations (so more time tending the machine). The fins on the BT60 copper-colored rocket were cut single-sided and assembled like clamshells -- If I'd needed them, I could've cut two sets at once. The fins laid out on the bench between the rockets have a span of 13 cm and a root light of 11 cm. I need four fins. With some creative packing, I could probably fit 8 pieces into the cutting available area, but I was not able to cut a complete set from a single piece of 12 x 24 plywood.
There are other constraints; for example the thickness of a piece of 3mm (nominal) aircraft ply might vary by ±.25mm from one end of the piece to the other. For precise thickness cuts (like the tabs on the fins that will fit into dados cut into centering rings) this reduces the effective cutting area for a single job.
All of which is to say, you could buy a pretty nice kit from Madcow or LOC for what
I'd charge you for a set of custom fins (again, I won't speak to how others might price their labor).
OTOH, it has occurred to me to run off a batch the of "formers" for clones of the
Centuri X-24 bug lifting body. Just because I want to make one, but I haven't yet had a job where I could fit it onto the stock with the other parts I was cutting.