My recollection is a little different, but you should know. The B7 was not an AeroTech motor, it was an Apogee motor that TVM produced at the Aerotech facility, and it was designed by a third party. TVM was mainly leveraging AeroTech's pemits, but also the facilities and supplies, and probably some labor as well. TVM was on site in Las Vegas when his motors were made. The E6 and F10, are clearly Aerotech motors, some of which were relabeled as Apogee motors. Apogee and TVM is due a little more credit for some of those motors like the B7. Low sales may have been a factor, but they were discontinued when TVM decided not to continue production at the new AT facility. I don't know the nitty-gritty details of the Apogee/Aerotech operation.
The C10, C4, B7 (and maybe the D3) motors were designed and developed at AeroTech back when Ed LaCroix still owned Apogee.
Ed wanted a smaller 'C' motor for Eggloft so the C10 motor was developed.
A longer-burn C4 motor for gliders was another specialty motor for Apogee developed by AeroTech.
These were both 18mm diameter motors but less than two inches long.
Ed really wanted a 13mm diameter motor.
The largest performance we could get out of a 13mm phenolic case would be a 'full' 'B' motor.
The B7 was a real challenge.
Scott Pearce spent a lot of time with Gary Rosenfield developing that motor.
Getting the 13mm casing was not an issue.
Creating a nozzle for the motor WAS an issue.
Ed didn't want to spring for a nozzle mold and AeroTech had no use for a 13mm nozzle.
Solution: Scott took 18mm nozzles and machined each one on a lathe to the size needed for the B7 motors.
It took him all day to make 100 of the nozzles.
Casting the propellant was another challenge as the propellant was difficult to pour into such small casting tubes.
Scott and Gary eventually figured it out.
Making the small diameter delays for the motors was not easy either.
Eventually, the first batch of B7 motors was created by AeroTech.
The motors were NAR certified with -4, -6, -8 and -10 second delays.
Those were cool motors. I still have several in my collection.
I used two of the B7 motors as a cluster in a 'C' eggloft event at a NAR meet.
Scott developed a special two-headed Copperhead igniter for clustered B7s.
The igniter worked great! I messed up by forgetting about drag-separation as the egg capsule came off the rocket at motor burn-out.
Qualified but last place.
Later, Ed would come up to AeroTech and do the final assembly of the B7 motors.
The propellant/delay would have already been cast and the nozzles made.
All the Apogee composite propellant motors were produced at AeroTech by AeroTech staff or later with Ed LaCroix handling some of the final assembly work. I was gone from AeroTech when Ed sold Apogee to Tim van Milligan so I don't know how/who made these special motors at that time.
That's the story of the origin of the Apogee composite propellant motors.