The exposure settings are going to be light-dependent...so, there isn't any way to share "canned" settings for. you there. The f-stop may also depend on just how close you are and the DOF you need to fit the whole pen in, and if you want maximum detail then there are going to be some limits there (by around f16 or so diffraction will start limiting your resolution.)
I am not great with flash, so I purchased some fixed lighting, a couple diffusing light boxes to enlarge the light source and give me softer lighting and shadows (which, is not necessarily always what you want...large diffuse lights can eliminate reflections you may want to keep in place on shinier pens!), and some booms, reflectors, and some other things to help me control primary and fill lighting and all that. Not terribly expensive, most of these items can be found for anywhere from $15-$30 each, although a good large light with an umbrella and diffuser may cost more like $50 or so.
With fixed lights, its easy to see exactly how your pen will be lit, get it set up just right, and then set up your camera at the various angles you want and get your shots. If you know your lighting, you can manually set your white balance, otherwise if you shoot RAW you can adjust that after the fact as well. I usually try to use a white balance that matches the kind of lights I use, so 5000k, 6500k, 2800k, etc. depending on the light. Gives me a more realistic view on the camera while I'm setting up shots.
I've tried to use my phone for photos...but, it just doesn't give me the quality or control I'm used to. I've been using DSLRs for close to 15 years, and I'm too used to being able to control every aspect of my shot.
You can get excellent results with a DSLR though, if you put a little bit of money into lighting gear, and spend a bit of time getting the lighting right.
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