These upgrade frames were one of my longest-running projects to date, taking about 1.5 years to bring from idea to production. I had wanted a new frame shape from the moment I bought my Mini back in 2007. I like Minis but am not very fond of their steep frame angle. I believe the high frame shape is mostly a by-product of the internal air tube system running straight up inside the grip, so some tricky redesigning is needed to achieve any other angles.
With that goal in mind, I set out to build a "standard" 72º grip angle, same as used by most markers and firearms that use a 45-style frame shape. In fact, the running name for this upgrade was the "Mini 45 frame", but I ended up having to rename it because the new frame couldn't use standard 45-style grips (rather it uses the Mini's stock/OEM grips).
The altered frame shape meant I needed to create a new method to pneumatically connect the bottomline air regulator to the Mini's stock air tube system. The stock frame places the regulator directly below the air tube, but this new frame needed a totally new design. There were a few ideas floating around, like using a sealed set screw air passage in the bottom of the frame, but ultimately I came up with a much better system using a spring-loaded air coupling (see picture below). The air coupling pushes against the bottomline regulator to create a seal, without having to manually adjust the tension on the stock air tube.
Prototype:
As mentioned, this project was conceived long ago but I was only able to create a prototype in relatively recent years. The problem I encountered was that the upgrade frame was a drastic change from the stock parts, so a LOT of time would be required for experimentation and development. The large amount of time meant I had to get all other projects off the table before I could begin playing with Mini frame ideas. Once I was able to clear the plate, I started making a few test components; the first was this air tube test bracket seen below:
It was now time to create an actual prototype of the frame itself. This was a longer process due to the complexity involved, but I was able to make a couple prototypes without much trouble (only two were functional, but is common for testbed parts like these)
The prototype frames were in testing for nearly 6 months before I was able to hammer out all the details. There were a couple changes made before production frames would be available, but many of them were minior. Noticeably, the metal area around the solenoid was strengthened, and the snatchgrip shape was streamlined. The trigger magnet system was also tweaked to provide frame magnet adjustability.
Production:
Once all the details were in place, Nummech began producing these in small batches in order to gauge demand. We quickly ran out and ended up making more, so I consider the project a pretty strong success.
Nearly as soon as these were released, people were immeditely interested in an altered version for Axes, so development began on those without much wait. The overall shape and most of the features were the same between frames, but the new Axe frame had a couple enhancements meant to remove unnecessary material around the air tube. The next batch of Mini frames also incorporated these features, which are seen below (these came to be known as the "v2" Mini VL frames).
Here's some pics of the finished frame installed on test markers:
