VaderSpade’s 80% AR-15 build - Milling, Etching, & Anodizing

[VaderSpade]

With a Tactical Machining Jig. Customer support at Tactical Machining is second to none, they are great to work with, and have always gone above and beyond.
http://www.tacticalmachining.com/80-pro ... ivers.html

First I want to thank everyone for all the help I’ve received on these boards. I’ve done a few of these now, and I just about have the kinks worked out, so I thought I would pay it forward, and help others with their builds.

The Tactical Machining jig is by far the easiest way to complete an 80% receiver that I’ve tried. I was lucky enough to find a killer deal on a nearly new mill for $850.00 on Craigslist.
If your going to try milling with a drill press I would recommend getting (at the least) an X, Y table, and a vise.

A small mill would be better. With a drill press you will need to go much slower. Although most jigs are designed to work with a drill press, there are a few problems; the most dangerous of these is your drill chuck coming lose at high speeds. I don’t recommend using a drill press, but I did with my first build, and sure enough the drill chuck came loose and buggered up my FCG pocket. I locked it back into place with RED loctite gave a day to set up, and had no further problems. If you do this you do so at your own risk.

I won’t be covering all the measurements and dimensions just yet they are easily available elsewhere. I’ll post a link at some point.


The setup.

The Tactical Machining jig is very straightforward, use this plate with this end mill, and
go slow.


I try to get as close as possible to the edge of the plate, for the outline, but I like to leave a few thousandths for the cleanup stage.

Make sure your cutting edges are below the plate, or you will be ordering a new one.


Watch your clearance. I can’t reach the back with this setup, but we’ll clean that up later.

After you have a good outline remove the top plate, measure twice, and cut carefully.


Just short of the .690 spec. We’ll get that with a full-length end mill, for a cleaner cut.

It always spooks me when I break through the selector hole. What’s that! Oh ya it’s O.K.




As I mover deeper I leave just a little more, kind of a step cut. This keeps shaving from being crushed against the side, and cleans up easily when we move to a full length end mill.


Note the depth mark on my end mill, this is my warning mark. Don’t go too deep.


My sophisticated measuring tool.


First stage done.

[VaderSpade]

Switching to the full-length end mill.


Taking those last thousandths off the sides and bottom.

Finishing the end I couldn’t reach with the short end mill. Measure carefully.


Make sure the trigger slides in before you change setups.


Now put the top of the jig back on with the trigger slot plate.
You may have noticed I skipped the second plate. That plate is for the full depth part of the pocket. If you’re going to use the edge of the plate as a guide it’s a good idea to use it. For me it’s just as easy to measure it in as I clean up with the long end mill.


I can’t express how easy this plate makes cutting the trigger hole. Before it was “Change tools from milling to drilling, take three measurements, drill three holes, change back to milling and hope you’re not too far off. Then file the little bit you WILL be off.”
With this Tactical Machining jig it take just a few moments.


Flip the jig and drill two 5/32ths holes.


Looking good.






Check the trigger, and upper fit. You don’t want to be filing after anodizing.

[VaderSpade]

Etching

Half the fun of building a gun is putting your own mark on it. I have been experimenting with different methods, and short of buying a CNC rig electro etching is the best method I have found.
I am etching with a jewelry plating power source but a battery charger will work (not an automatic one).

First we make a stencil, by hand or with a vinyl cutter. I use one from U.S. Cutter;
http://www.uscutter.com/GreenStar-Intermediate-Calendered-Vinyl-24quot-x-10-Yard-Roll_p_1020.html


Tape is used to pull the stencil from it’s backing in one piece.


The stencil is placed on the receiver with the letters in place.
This makes the stencil easier to place, and gives a solid surface to work against.


The letters or graphics are then “weeded out”. You will need a magnifying glass (I double up reading glasses) a long needle, and tweezers to pull the bits you want removed. Carefully remove (weed) the parts you want etched.


Carefully lift the edge of the bit you want to remove.


Pull the bits away with tweezers.


My charger is set to the full 12 volts @ 10 amps. The amps that trickle through are determined by how much surface area is contacted by the Q-tip. Place the clip about halfway up on the swab. I place a little solution in a shallow container and dip the Q-Tip, make sure it gets wet up to the clip. There will be bubbling, when this slows and the Q-Tip turns black repeat the process. It can be hard to see how deep your going, when the little islands within the a’s & e’s won’t stay in place you’ve gone about as deep as possible.

I should say large open areas do not work as well as smaller outlines.
I use about ½ cup of vinegar and a teaspoon of salt.


Tape the surrounding area to avoid sparks and etching areas you don’t want etched.


I mixed white vinegar with a little salt, dipped a Q-tip into this solution and attached it to the negative side of the charger, then clamped the positive side to the lower.
It takes awhile, and starts slowly, but after you break through the surface the pace picks up.









A few tips in response to some questions I've received.

A cheap NON-automatic automobile battery charger 12 volt, 10 amps should work fine.

An automatic automobile battery charger would read a dead short and turn itself off.

One thing I learned the hard way is that the positive side needs to be connected to the lower and the negative side to the Q-Tip. I got it backward once and it ate away the clip holding the Q-Tip, and barely marked the work piece (in this case just a piece of scrap).

If the bare clip touches bare metal there will be sparks, tape off the surrounding area.

I recommend testing any setup on a piece of scrap before trying it on a lower.

Example of text;

Manufacture
City State
Model
Caliber
serial #

Max is 10 maybe 12 letters/numbers per line.

If you want room for artwork the Manufacture and city should be moved to above the hammer pin/selector area.

[VaderSpade]

Anodizing

I’m using the Moonlite Anodizing kit, and although I have nothing to compare it with I think it works just great. They have a great how to, so I won’t try to explain everything. I’ll just post pictures with some captions, showing the lowers being anodized.
http://www.focuser.com/anodize.html


The lineup.

Prep the surface, and clean. Submerse in 140 degree cleaner for 5 minutes, then rinse well.


Etch at room temperature for a few minutes.

Your part will turn black. Rinse.


Deoxidize/Desmut the part at room temperature about 3 minutes, and rinse well.

It should be shiny again. J


Now we’re anodizing! 68-72 degrees for 75 minutes. Read the instructions as to how to figure voltage and time with your power supply.

It should have a nice golden tone when it’s done. Rinse twice.


Before and After.

Into the dye. 120-140 degrees for 5-20 minutes depending on how dark you want it.


Looking good. Rinse it.

Finely seal it at 180 degrees for 20 minutes. And rinse for the last time.
After that final rinse I like to dry it with a hair dryer, and oil it up.


Finished. Never let the part dry between steps, and because of the heat used in some steps that can be tough.

Why build your own???

For me I’m building family heirlooms, these guns will be here long after I’m gone. I hope they will say something about what I stood for.
That’s the second amendment etched into the upper receiver.

As to reliability, mine are as good as the best out there. Being perfectionist drives a lot of us that build our own.

I have collected arrowheads forever. Most were just chipped to be shot once and never seen again. The builders didn’t put much time of effort into them, and why would they.
But others are works of art. Why? Why would someone put so much time and effort into an arrowhead?
If you can find the answer to this question you will have your answer.
And yes I have built my own Bows and Arrows; I still chip arrowheads now and then.

[patjsimpson]

Great Tutorial Thanks!
Pat

[junior]

Thanks again for posting this here

[VaderSpade]

I have been getting a lot of questions on etching, so I just revised, and added more photos to the etching part of this thread.

[SuP]

Excellent post!

[Loren]

Dose it matter the direction you cut with the side of the mill bit, relative to the driection it turns? For example do I want the work (area to be cut away) to go into the bit's rotation (like a circular saw) or with it? Does this matter?

[VaderSpade]

Dose it matter the direction you cut with the side of the mill bit, relative to the driection it turns? For example do I want the work (area to be cut away) to go into the bit's rotation (like a circular saw) or with it? Does this matter?

I try to cut into the bit's rotation, but often need to back up a little to clean out corners. The only differences I’ve found it makes is speed. I can move a little faster without vibration when moving into the bit's rotation than I can when backing up.