Danger Glitter

 I have no idea what kind of steel P38s are made from, so machining and welding are going to be guesswork.  I had the raw forging and the original frame piece XRF tested to see if I could narrow down the alloy used, and the results were fairly inconclusive.  The manganese content was in the range of 4130, spark testing looked similar to the 4140 I compared it to and when I heated and quenched a chunk, it got hard-ish so it's got some carbon in it. For lack of better options, I decided to treat it like 4130 for machining and welding.

I hate machining steel.  There is nothing I like about it.  It's not very forgiving if you do a dumb, it's hard on tooling, and worst of all, unlike aluminum the danger glitter is more than happy to stab itself into your fingers like tiny little needles.  Machining from a raw forging like this presents it's own challenge too because I know there is a lot of extra material there, but I don't know where.  After whacking off the chunk of forging that I needed, I decked the top and cut the overall width so I would have some straight, square surfaces to work with.  I decided to start my CNC work with the inside of the trigger guard because its the area with the least amount of extra material on it.  I tried to centerfind the pocket with the proper tools....and promptly broke a cutter on the first pass because it was too far off.  So I eyeballed it instead and didn't break the next one.  Since the trigger guard is a weird shape, I also decided to drill the trigger pin hole to use as my program center so that I had an easy to find reference point.

Slow and steady is how my little mill mills, and with mildly hard steel it's even slower.  My feed rate was pretty average for the material, but my depth of cuts were very shallow.  A whole day of machining got me this far:

After a whole lot more painfully slow machining the first side was done.

New Project Time: the Megatron P38

 If you've been following this blog long enough, you know that Transformers is one of my favorite things(the real Transformers, not the smashed Coke can looking Michael Bay stuff).  I also like guns(which is why most of you are here at this point), so I decided to combine the two.  While he's a plane or a tank or something now, the original G1 design for Megatron was a Walther P38.  

I don't mind toys that look like guns, but I'm generally opposed to guns that look like toys(looking at you Lego and Nintendo Light Zapper themed Glocks).  I'm making an exception here because the original Megatron design still looks very much like a real gun and is not brightly colored in a way that would attract a curious toddler(cough Lego themed Glock cough).  Here's the look I'm going for, although I probably won't add the scope(pictures stolen from the internet).

I've been thinking about this project for the better part of a decade, but never got around to it.  Another thing you know if you've been following long enough is that doing things on the cheap is kinda my thing.  At this point in history, real P38s are fairly expensive.  More than I want to spend anyway(plus, I fully intend to engrave the Decepticon logo on the slide and I'd feel bad doing it to a nice gun).  I found a CAD file, but the frame is pretty complicated.  I think I have the skill to machine one from scratch, but I definitely don't have the patience for it.  Then, as luck would have it, I happened across part of an original P38 frame for cheap.  Some WG members pointed out that there were a few raw frame forgings available too, so I picked one up.  I also picked up a P38 parts kit on sale at EGP, and we're off.  Here's what I'm starting with.  I 3D printed the missing frame chunk and now I have to machine the forging to match.