I definitely agree with the "make what you know" thought process. It's a lot easier to draw inspiration from hobbies and interests or even those of friends. I started out doing some job shop work for friends and eventually started designing a better throttle lock for my own bikes. I wanted something that solved problems I had with every other one ever made and after 8 solid months of prototypying and redesigning eventually I had a product I was willing to sell. This was all done on my X3 mill I converted. The first 1500 units were made on that before I could afford a Tormach. Check out the product (OMNI-CRUISE: Universal Motorcycle Throttle Lock) and you will see the 4 main parts. Top and bottom are aluminum with 14 different processes to get those two made including 0.15" wide slots through the 1" tall 0.25" wide bottom. The center pivot nuts are machined to length on the mill, cross drilled and tapped there as well. The bottom Delrin slide is machined from plate and the countersunk holes are also all done on the mill.

Today I have sold over 10,000 Omni's... and have since had to upgrade to a Haas TM2P as my main machine so I can walk away longer while running 3x as many parts per set up vs the Tormach, but the Tormach ran 7,500 Omnis by itself at $50 retail each for 4 parts per (I only sell a small percentage at retail and the rest to dealers and distributors). Ha, never did this math before:

Since Dec 2012
Total parts machined for Omni-Cruise --- 48,000
Total parts hand assembled (inc hardware) --- 168,000

Ouch.

I only work on Omni-Cruise about half the time and the rest is split between jobshop and new product development. I have only been able to get one other product to market and have another about to launch this month, but the job shop work is VERY erratic and painfully "when it rains it pours". I tend to get several jobs at once and have to turn one or more away to not get behind on my next Omni batch but have some great customers that actually plan ahead and bring me "when ever you have time" work as well. Today I am re-machining racing brake calipers. Tonight I am machining customer rollers for test units used for calibrating electronic bike sensors. Tomorrow I am machining 30lb steel door counterweights. Most nights I assemble Omni's and watch a movie with the wife who usually helps assemble. She is amazing and knows her limitations but does what she can.

Inventing and making your own stuff is WAY more fun and usually lucrative. Getting knocked off is something that just happens. I improved upon any previous design out there with my throttle lock... only took 6 months for one of my competitors to use most of my ideas to upgrade theirs to do the same thing I invented mine to (that none had ever done before). Naturally theirs came out at 40% less money, but I still sell a crap load because many people can tell the quality just from the design and pictures, not to mention reviews and magazine articles. Plus there are actually a few of us left that buy American; I went with a Haas mill and Epilog laser specifically for that purpose.

Make a good product and people will buy it. Make a cheap product and people will buy it. Make a product with a small market and it better not be cheap. Make a product for iPhone market and it better be cheap. I have a very limited clientele for my Omni and my new line of products has an even smaller market unfortunately but retails at almost $200-$700 per sale.

There isn't much I would change if I could about what I have done. I own my own business. Have a shop. Lots of toys. Most importantly I'm the boss so I get to work whichever 12-16 hours a day I feel like it.

Last toy was a $3000 high speed spindle Cat40 for the Haas to make up for the Tormach Spindle Speeder I just sold with the mill. Previous toy was an industrial parts tumbler. Next big toy will be a 6,000 lb+ slant bed lathe. (already have one in mind). They say you should ask yourself what you would do if you had a million dollars. Whatever you would do with it is what you should do for a living. If I had a million dollars I would buy a free standing shop with a large outside fenced in lot, fill it with a few more Haas machines, hire someone to do the damn paperwork, and do the exact same thing I do right now. I haven't "worked" a day since I quit my day job, but by god I have never had so little free time in my life either.