www.HomeGunsmith.com Archive
Archive Date: Apr. 24 2018, 04:00 ET
This is an archive! Click here to go to the live site.

Home > Building The Perfect Piece at Home > AR-15 Specific Home Smithing > Started machining!, Receivers
Click here to go to this topic on the "live" site.
Posted: Aug. 25 2006, 22:11 ET

I finally started machining today, I got the material cut, I cut a 1.5x4x8.25(extra long) solid chunk of 6061 T6 aluminum. I'm hoping to have some sweet receivers.

My design:

I set up the mill, zero'd the vice,

set in my parallels and my big chunk of metal and zero'd that then moved to the front takedown hole and zero'd that there and drilled and reamed.

Centerdrilled everything

I then went and drilled and reamed the rear takedown, drilled and reamed(actually used an end mill to ream it :D ) the selector hole, drilled the mag release hole, then the .156" holes, I drill-reamed the .156 holes after drilling them to 1/8" for good measure, I would have reamed them but I don't have that size.

More to come(probably not in a timeley manner)

The upper design is still up in the air, I'm looking to do a left hand cocker and maybe even the buffer spring up front. check out this thread: Sidecocker ideas

If anyone sees something that doesn't look right or could be improoved apon, let me know!

Enjoy guys!


Posted: Aug. 26 2006, 16:10 ET

Mmm.... chunky.  Looks great, can't wait to see more progress!

Posted: Aug. 28 2006, 10:48 ET

Very good. I like the pictures and explanations, keep it up!

What kind of mill are you using?


Posted: Aug. 28 2006, 14:14 ET

JFettig, could you put together a blue print of your design that could be used has a temp-let that could be pasted on a piece of aluminum so the holes could be drilled and rough shape be cut out?

I know some people dont like the block type shape of some of the AR15 lowers, truth is it may help some people (like ME) some day build an AR 15 lower from scratch.

Keep up the good work! (and please think about that templet)

Posted: Aug. 28 2006, 18:50 ET

Hey guys, I am using a mini mill I origionally got from homier.com and converted it to cnc. I think if I had a manual mill I'd rather do it on there for some reason right now.
I did design it to be simple enough to machine it manually minus that radius which can be changed.

Brokengun, some of the holes can be drilled like that but some can have a little tighter tollerances, specifically alignment.

After I complete this, I'll probably release the model to the library, as well as the prints I make for making this(some are very detailed, some aren't)

I'm hoping to be doing some more machining this week, I have some of it dimentioned out, the outside infront of the magwell and maybe part of the top plane.

I'm having issues with my mill not having enough travel to do some of the work so a few issues might arise or cause a little difficulty.
I drilled and reamed my takedown holes acurately as well as have square edges so I should be able to locate stuff when I have to move the part in the vice.


Posted: Aug. 28 2006, 21:42 ET

Again, I like all the pictures and explanations, so keep it up.

I'm also interested in the machines :) What kind of band saw is that? Do you have any pictures of the whole milling machine? What kind of CAD/CAM program do you have? That looks like a big vise to have on a mini mill. What size is it and where did you get it? I'm getting a mini mill (hopefully) this week, and I'm starting to collect tooling for it. Thanks.


Posted: Aug. 28 2006, 21:51 ET

its a cheap 4x6 bandsaw from harborfreight with a expencive 6-10tpi variable pitch blade from grizzly.com that does an awesome job... oh and a new motor  because the stock motor fried.

Yes, I have some pictures

I am running solidworks right now, and no cam, I hand program 99% of what I do.

The vice is a 3" screwless vice that opens 4"

I don't know what mini-mill your getting, but make sure to get the biggest one you can(talking the sieg x3, or grizzly 'small mill' at least)
If you want more mill info, start a thread or pm me :)


Posted: Sep. 2 2006, 12:32 ET

I made some progress :D

Heres the profile at .01" to make sure I didnt screw up when programming the mill.


Finished with that program/opperation. I think I'll do a little more today.


Posted: Sep. 2 2006, 13:24 ET

Looks good! How long did it take you to program the last operation by hand?


Posted: Sep. 2 2006, 14:21 ET

I mapped out all the coordinates in my solidworks print by offseting geometry and dimentioned everything out, I'd say It took about 1/2hr to write the program but I also made 2 test runs and modified it a couple times to make it clean out all the material so there was nothing left in the corners of the peice.

It probably took half hr to machine that or maybe a little less.


Posted: Sep. 2 2006, 15:43 ET

Most excellent JFettig, looking fwd to more

Posted: Sep. 2 2006, 18:59 ET

Way to go Jon!
Cant wait to see more!


Posted: Sep. 2 2006, 19:55 ET

:anim_beer: great work & photos!
keep 'em coming...

Posted: Sep. 2 2006, 22:04 ET

That is impresive, I'm just in awe of you guys that can write programs like that.

Posted: Sep. 4 2006, 13:24 ET

More progress! I surfaced the top (where needed) and milled out the recesses on the magwell. I will leave the mag release slot for later after the magwell is cut because it may push the drill around If I choose to go that route.

I'll soon cut the bolt catch slot, not today but that will be one of the next opperations.

I'm short on travel, I cannot cut the back plane or too far, so I may leave that and the grip area for another mount, I'll likely have to move the vice and/or turn the material. I know I can turn the material and do the top plane and radius and maybe I can do the back too.

Heres a few pics:

The right side of the reciever will look almost identical with the contours. I did this for 2 reasons, to make it look good as well as have something to clamp onto when doing the magwell and FCG pockets.

Enjoy :)


Posted: Sep. 4 2006, 13:42 ET

Looks good Jon! One question I forgot to ask-how much metal can you take off in one pass? How much would it be if you still had the stock motor?



Posted: Sep. 4 2006, 17:02 ET

I've taken 1/4" with a 3/8 roughing end mill before with lots of noise and chatter, I typically just do 1/16" but it really doesnt have a problem doing 1/8 other than sometimes I'll get some chatter and it makes some gross looking stuff. I know it'll do a good job with a 1/16" pass so I typically just go with that. I've done .1" with my 2" face mill once (about 50% stepover) at 6000rpm with the new motor.

I typically did the 1/16" pass with the old motor, I do that for anything 3/16" and bigger and about .05 max for a 1/8" end mill and typically .02 or .03 for a 1/16" end mill. When you use the small end mills, make sure you have some way to evacuate the chips, whether it be flood coolant or an air stream. For manual milling machines, I prefer the koolmist setup for a small amount of coolant and compressed air, must have good ventalation when using those.

I actually climb milled this whole thing so far with very good results(dont try that on a manual mill!) everything is comming out very smoothly.


Posted: Sep. 9 2006, 15:35 ET

Making progress!

My mill enclosure is starting to leak, I've been goobering crap into the cracks to keep me going, hopefully I can finish this before I have to pull it apart and redo it.


Posted: Sep. 10 2006, 02:07 ET

Lookin' good.  Keep the chips flyin!  :thumbs:

Posted: Sep. 12 2006, 19:28 ET

What do you think, should I engrave something like this on the left side of the magwell?

thats a fender spacer I made for a chopper...


Posted: Sep. 12 2006, 20:51 ET

Go for it! When I do mine, I'm going to research all the markings that were on the A2 M16 and duplicate them......I want to copy it as closely as possible. However, doing something like that would give it more personality.


Posted: Sep. 18 2006, 22:30 ET

Well this sucks.....

I kept telling myself that I should lay the origional over mine. Everything fits perfectly except one of the most important parts! the hammer pin hole!

The hole I drilled is .036 too far forward.

I'm not quite sure what I should do about it. I could plug it somehow, If I press a peice in, it will likely come loose eventually or jar just a little bit. Welding makes a mess and I don't have a tig welder, I saw that similar fix using the aluminum screw which I think isnt much better than pressing a peice in.

One side is machined to aproximate size right there, the other isn't.



Posted: Sep. 19 2006, 01:10 ET

Thread it and put an aluminum set screw in it using loctite #620 "retaining compound."  This stuff is green and it will *not* come loose any time soon.  Choose a diameter that will encompass the whole size of the pin hole you need in it's correct position, so you drill that hole in your plug only, and not through the threads.  When you thread you hole, run the tap in just far enough that the last thread isn't quite completely cut.  Almost, but just not enough so that when you run your set screw in it takes a little force to put it through.  Just enough force that you can't "finger" twist it through.

Everything aluminum that we press fit at work we use #620 on and I swear by it.

Posted: Sep. 19 2006, 07:28 ET

Thanks, I was thinking I'd do that, but instead of threading only far enough, I'd thread it through but when I  turn my set screw, I'd make it a super tight fit.(I'd thread it myself)


Posted: Sep. 19 2006, 20:03 ET

It depends on what finish your going to put on it if you use a spray on finish  you can hide the plug pretty well. If you anodize it you'll probably never be happy with a plug repair. If it was mine I'd make a special pin with a head .072 bigger in diameter and ream the hole thats off back on target and to the size to fit the new pin that would get everything back in alignment .

Posted: Sep. 19 2006, 20:12 ET

scasa, I was thinking about doing the same thing. It is possible to do still. I do plan on anodizing it too.The problem is that both sides of the receiver are off that far. I'd have to get a hammer with the .072 hole in it also. I believe thats the size older colts used or something similar and I think there are hammers with that hole. I just have to make sure theres some 2 stage triggers with it like that(or modifiable).


Posted: Sep. 30 2006, 11:35 ET

Excellent work, great photos, and especially, nice job on the CNC conversion.  I've done one myself and it is NOT a trivial job!  :D

Posted: Sep. 30 2006, 16:32 ET

I did a little more machining, started on the top plane but for some reason in the middle of a cut the computer shut down. being tired and frusterated I just quit there, I'll resume it later. oh how I wish I had a bigger mill!

Swede, you've probably seen my machine multiple times at cnczone. Thanks for the compliments.

I now wish I would have coughed up the $$$$ for the X3 earlier this summer. I cant really justify it now.


Posted: Oct. 7 2006, 14:42 ET

alright guys, I finially finished half the top plane and radius and back plane as well as the side. The only parts on this whole side that are missing is the bolt catch slot, the radius on the back as well as the sides of the buffer tube hole area. I can machine the opposite side now.

I am now uploading high-resolution pictures if you want to see them:

I'm also looking for suggestions on what I should call 'SAFE', 'FIRE' and if I should put 'AUTO' in there for display purposes or what to call it. I really like the one I got in my avatar :D I do plan on putting a skull and bones as you see on bottom of page 2(unless someone has a better idea)


Posted: Oct. 7 2006, 19:45 ET

looking good Jon - great progress so far.

How about "Get Some" for one position? :-)


Posted: Oct. 7 2006, 23:25 ET

hmm, I want something maybe catchy or something.

I'm thinking I'll also modify the selector to flip back to "AUTO" but still just be another semi-

I wish I knew who did the one in my avatar, I'd feel bad if I just flat out stole it.


Posted: Oct. 8 2006, 00:29 ET

Parley, Plunder, and Pillage.


Posted: Oct. 14 2006, 16:28 ET

Any further progress? :)

Posted: Oct. 14 2006, 20:11 ET

not yet, been busy this week and weekend. I'm not sure if I'll be more or less busy in the upcomming weeks. I have 2-1/2 more months at home till I go back to school again for a semester, I'm hoping to at least have the lower completed.

I did make a new comp though :D I'll post that in another thread soon.


Posted: Oct. 15 2006, 15:37 ET

I sent you a PM about your CNC conversion....can you get back to me when you have time?  :)



Posted: Oct. 15 2006, 20:32 ET

Blackgun_Fun, I did not get a pm. try sending another.


Posted: Oct. 25 2006, 13:11 ET

You are an inspiration, thanks for the nice posts!


Posted: Nov. 29 2006, 22:19 ET

Wow, I totally forgot to post these pictures, I made some progress a while ago:

high-res pics are uploading right now.(just take out tn_)

I just need to finish the top plane, back then the surface thats not machined as well as the angles and radius around the hand grip area.(and the rest)


Posted: Nov. 30 2006, 11:09 ET


Posted: Mar. 9 2008, 23:21 ET

I'm about 99% done now! I haven't finished the buffer tower, I'm getting a Lo-Pro upper from DPMS and I figured why not match it to the upper?

To do my magwell, I didn't have any long end mills smaller than 3/4" so I roughed it out after I drilled the corners and used a fuzzbean shaper attachment in my mill :D

After this I just took a file to clean up the burrs, it turned out really  nice! I used the ray-vin guide for the remainder of the lower.
I'd say it turned out really nice!

Huge chamfer on the magwell

This lower is going on my .300 whisper pistol, I'm just waiting for the upper, charging handle, gas tube, pistol buffer, and FF tube, all of which are ordered.

I plan on putting a rifle scope on this if the recoil isn't too bad, I don't think that with a good cheek weld on the buffer tube I'll have much trouble with getting a scope in the eye, at least thats what I'm hoping, I'll post a pic of the black eye if I do :;):


Posted: Mar. 10 2008, 00:21 ET

Nice ! Would it be a lot of trouble  to stretch it out and make one in a .410?

Posted: Mar. 10 2008, 03:56 ET

Quote (scasa @ Mar. 09 2008,21:21)
Nice ! Would it be a lot of trouble  to stretch it out and make one in a .410?

YES!!!! AR410!!! Lets do this!

Posted: Mar. 10 2008, 10:03 ET

Shouldn't .410 fit in a regular mag? I'd imagine that you'd have to change the lockup because you'd need a way to feed these things.

I'm not interested in a .410 feel free to make your own :D


Posted: Mar. 10 2008, 22:55 ET

I just tried a 2 3/4 shell and it was really close to fitting, you could force it in but it was really tight

Posted: Mar. 11 2008, 01:29 ET

What's this pistol going to wind up weighing?  With your heavy barrel, linear brake, and a mild round, you might just get away with a rifle scope.  Sure would make life easier (and less expensive).  I'd still get a "friend" to do the first test fire looking through the rifle scope though.

Posted: Mar. 11 2008, 07:55 ET

Good question, I don't think it will be too bad, the barrel isn't "heavy" but it will weigh a decent amount. The scope itself will be a decent fraction of that weight.

I'll be getting more parts toward the end of the week, I guess it doesn't help that I don't have a scale.

I wonder if I'll need angled rings or an angled base? The drop on these bullets at long distance is around 100 inches+


Posted: Mar. 15 2008, 13:56 ET

I got this lower blasted, it looks awesome. I now have to convince Cobbler to let me set up an anodizing setup at his place :D

I really like this:

I couldn't hold it in and take a picture at the same time, but when the mag release is depressed all the way it comes out flush with the side.

I have my pistol buffer now as you can see, I have the rest of the stuff for it but not assembled, looks like I missed a turn on the z for the buffer retainer hole, won't go down far enough!


Posted: Mar. 15 2008, 14:16 ET

nice. which pistol buffer is that?

Posted: Mar. 15 2008, 14:20 ET

Its the ACE pistol buffer, I have the pad that goes around it too. Its about the same size as a carbine buffer tube but much nicer.


Posted: Mar. 15 2008, 22:29 ET

That sure turned out nice !

Posted: Mar. 16 2008, 10:13 ET

Exelent job Jon! I always wondered why the trigerguard was a seperate piece. With it going all the way across it looks like the lower is much stronger. Very nice, Ron :thumbs:

Posted: Mar. 16 2008, 13:47 ET

Beautiful :cool:

I guess I need to learn some CNC :;):

Posted: Mar. 16 2008, 14:00 ET

Quote (Ron458 @ Mar. 16 2008,07:13)
Exelent job Jon! I always wondered why the trigerguard was a seperate piece. With it going all the way across it looks like the lower is much stronger. Very nice, Ron :thumbs:

on the original design, it's so the 'guard can be flipped down to allow access to the trigger w/ big bulky gloves in winter. :)

Posted: Mar. 16 2008, 14:37 ET

Thanks guys,

Madjack, only the outside of it was done with CNC, With my design, you could easily do it on a manual mill.
I'd share it with you but I know there are a few flaws in it.

Yup, goober is correct. I've never had any need to flip it down so I went with this. I may do a little more reshaping of it like some others have done by turning the thing upside down and taking out the sides.


Posted: Mar. 16 2008, 21:22 ET

great work your design significantly simplified the design. I look forward to seeing the prints of your design even if they are flawed.

Posted: Mar. 19 2008, 20:35 ET

out standing work! Thanks for the pics!!

- sorta funny-lookin rounds in the mag though?? ???

(just pullin you leg!).  

Keep it up. Lookin great.

Posted: Mar. 20 2008, 09:00 ET

Can you add a pix or touch on the different jigs you needed for this build.  Going to be an awsome pistol.  Think I need one!

Posted: Mar. 23 2008, 00:48 ET

Quote (bsouthnow @ Mar. 20 2008,08:00)
Can you add a pix or touch on the different jigs you needed for this build.  Going to be an awsome pistol.  Think I need one!

I didn't really use any jigs, just a block of aluminum, 3" screwless vice and a 4" angle plate. Part of the design was to make it so I can clamp it anywhere and have something square to work off of. The sides of the magwell are the same width as the buffer tower and everything is centered in there. I'll try to find some time to fix the model(just found another error, my bolt catch spring hole is too deep!).


Posted: Mar. 23 2008, 14:05 ET

Would you be willing to upload your solid model?

Posted: Mar. 23 2008, 22:32 ET

I'll make a note to fix the flaws and I would be willing to send it to you when I do. bug me about it in a couple weeks again, hopefully school will give me a break sometime soon.


Posted: Mar. 24 2008, 02:45 ET

That looks great!  Once you get all tthe bugs worked out of the design, I would love to get a solid model and blueprints.

Posted: Sep. 22 2008, 14:06 ET

Here is a picture of the pistol in its current configuration. I'll be putting a finish on this sometime in the near future.


Posted: Sep. 22 2008, 15:23 ET

This is so freaking amazing. I'd love to see a custom simplified upper (no forward assist) with a fixed charging handle.

Posted: Sep. 22 2008, 17:25 ET

The upper I have there is a DPMS Lo-Pro, no FA or deflector. it doesn't ding up my .300/221 brass as much. The charging handle is still there. Someone makes a modified bolt carrier and upper for a fixed right hand charging handle. I prefer mine not to move even though the position of the stock handle does suck.


Posted: Sep. 23 2008, 03:40 ET

Quote (JFettig @ Mar. 23 2008,22:32)
I'll make a note to fix the flaws and I would be willing to send it to you when I do. bug me about it in a couple weeks again, hopefully school will give me a break sometime soon.


Nice job Jon, any chance you have time to upload your solid model? I really like the clean and simple lines of your design.

Posted: Sep. 23 2008, 08:23 ET

PM me your e-mail address and I'll e-mail it.


Posted: Nov. 7 2008, 14:47 ET

I'm getting ready to engrave this and I want to figure out what to put on around the selector switch.

Here is what I have so far to engrave:

Posted: Nov. 7 2008, 15:36 ET

Slaughter & Serenity


Play & Pause


you could use icons (play & pause):

or (power & stop)


Posted: Nov. 7 2008, 18:46 ET

Quote (SloChild @ Nov. 07 2008,15:36)


I also like the HK style pictograms.

Posted: Nov. 7 2008, 21:41 ET

From what I'm reading all over the net, you should be able to sell lowers as fast as you can make them. It seems that all kinds of 'assault weapons' are flying off the shelves and lowers are impossible to get. GetRDone :D

Posted: Nov. 8 2008, 02:22 ET

Nevada, I sure can't make them very fast! I'm also not licensed to manufacture :)


Posted: Nov. 13 2008, 19:40 ET

Here is what I went with:

Nothing around the selector...yet.


Posted: Nov. 13 2008, 19:56 ET


Posted: Nov. 13 2008, 21:06 ET

What does the other side look like ??

Posted: Nov. 13 2008, 22:03 ET

I like the serial number... I hope you get to fill in any gaps.:D
very nice

Posted: Nov. 14 2008, 01:38 ET

The other side is blank so far, I have nothing.

I'll be serializing my 9mm AR next... its either:
299 792 458


Posted: Jan. 24 2009, 17:59 ET

lmao just realized your SN is Avo's #. nice touch  :notworthy:
missed it the 1st time i read this thread.

Posted: Mar. 2 2009, 07:53 ET

Man, this thing looks better than the milspec.  The angles are amazing.  A four rail handguard, flat top receiver, magpul MIAD grip,  and squarish buttstock like a magpul CTR would mirror the angles very nicely for a  super "modular" look.