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wallpep
April 05, 2002, 17:22
Has anyone done a FAL raw forging? Is it difficult? What kind of tooling is required? How long did it take? I'm new to this type of rifle, matter of fact I'm absolutely clueless about the FAL, so any help is appreciated.

avanarts
April 05, 2002, 18:08
It would take far more than the average home workshop to finish one of those raw forgings. Every surface must be machined, every hole must be drilled, and every thread must be tapped.

I have one of the forgings that I bought just so I can say that I have one. It's a big heavy chunck of steel.

If someone would just market an 80% receiver for the FAL, that might be worth taking on.

[ April 05, 2002: Message edited by: asig220 ]

medicmike
April 05, 2002, 20:58
Thought about doing one of these but after looking into it I decided it was well beyond my machining skills. Lots of milling operations. An 80% reciever would be wonderful if someone would start making them!

bushka
April 05, 2002, 23:15
max you are truly mad,unless you can read a blueprint,have a milling machine of some sort and all the attendant tooling/clamping accesories and measuring tools,forget it.
but if you don`t care about how it ends up looking it is possible to get a functioning far away facsimile of a fal with a drillpress
and vice.etc.if you go on the cheap please realize that it will take at least 1/100th
the amount of time it takes to scrape one out
as it does to just buy one done outright.

blackbird
April 06, 2002, 02:30
Look at a finished receiver some time. You will need fixtures to hold it in at least 4, possibly 6 positions. You will need some tools for specific cuts (like the charging handle rail), the cost would add up very quickly. You MIGHT be able to mill and then file the magwell but sensible people would broach it. When you are done, assuming it is of a strong enough alloy, you will need to send it off for heat treatment. This is not optional given the locking method of a FAL. If the alloy is unsuitable, you would probably be better off starting with some square barstock 4140 Chrome-moly steel.

Bottom line, if you have lots of money and time and just WANT to do it, go for it. It can probably be done if you can locate some accurate blueprints and/or reverse engineer a finished one.

If on the other hand you are thinking you can save some money... sorry to be the bearer of bad news... you can't make it for what you can buy it even if you completely neglect the cost of your time.

[ April 06, 2002: Message edited by: blackbird ]

wallpep
April 06, 2002, 18:12
I run a machine shop and have plenty of tooling, not to mention outside vendors, so that is not a problem. Compared to an AR-15 lower, how hard could it get?

Billyboy, Ive been told that I am quite mad a few times, but it usually means that I'm about to have a lot of fun.

cc48510
April 06, 2002, 18:31
I would like to get some of these and finish them enough to install the main parts, but not more than 80%. I think they'd make nice blocks to keep unfinished parts kits on until you can be finished.

They might also be useful for display replicas, etc...

blackbird
April 07, 2002, 01:36
Originally posted by madmax:
<STRONG>I run a machine shop and have plenty of tooling, not to mention outside vendors, so that is not a problem. Compared to an AR-15 lower, how hard could it get?</STRONG>

Considerably harder since some of your critical relationships are in the upper receiver on a FAL. Things like your bolt quide slots, locking shoulder recess, etc. The AR lower is a simpler proposition and is aluminum. Chrome-moly makes it much more interesting. Like I said, if you can find some accurate drawings (hint: No need to look on the auctions) that would be hurdle #1.

I am not aware of anyone having succesfully completed a FAL receiver from a raw forging or casting on a "one-off" basis.

[ April 07, 2002: Message edited by: blackbird ]

BRM308
April 08, 2002, 09:53
Madmax. Now that everyone has said its not possible, go and do one and prove them wrong.If you have a complete machine shop at your disposal and the imagination you should be able to do it. I know I'm gonna give it a try.
couple of things.
The locking shoulder to bolt face recess is critical. And I thought that once that was established, I'd mage a plug for the barrel pilot hole already in the casting and with the bolt installed center mark for the barrel hole and drill a pilot hole from the back. Then fixture it in a lathe faceplate and bore and thread for the barrel.Then face the reciever.Just some ideas.Good luck

Templator
April 09, 2002, 13:57
,.. you'll go crazy,...

SF
April 09, 2002, 14:18
What Templator said :eek: This is a MAJOR tooling , fixtures, and special cutters undertaking,not to forget the proper metalurgy,heat treatment and precise alignment of all the above just to save $250,but more power to you if you have the time ;)

BRM308
April 09, 2002, 15:29
Madmax. I apologize. I was wrong. Its clearly impossible. Take all this good advice and give up now. :rolleyes:

HatchetJoe
April 09, 2002, 16:12
Originally posted by madmax:
<STRONG>I run a machine shop and have plenty of tooling, not to mention outside vendors, so that is not a problem. Compared to an AR-15 lower, how hard could it get?

Billyboy, Ive been told that I am quite mad a few times, but it usually means that I'm about to have a lot of fun.</STRONG>

Ignore these guys, they just don't realize where the recievers come from to begin with. The challenge is getting a good set of prints with metallurgical spects on the stell and Heat treat specification. Then work out the jigs and have at it. Although I question the desire for just one.

medicmike
April 09, 2002, 21:08
I say you should go for it.
Might give some of us the courage to give it a shot. Yes it will be a lot of work but it is always cool to do it yourself! ;) Just be sure to post your mistakes so those that follow won't repeat them :D
Keep us posted!!!

blackbird
April 09, 2002, 23:54
Guys! Guys! (and BRM). Clearly it is not impossible. The replies here address the specifics of the original post.

Has anyone done a FAL raw forging?

Don't know of anyone who has and I do frequent forums and groups that do a lot of home building. Have built AK and AR receivers myself and a few homemade experiments.

Is it difficult?

Yes, it's steel, not aluminum or sheetmetal. There are lots of off-axis cuts, undercuts, thin sections (charge handle slot, for example). Because of the locking scheme on the FAL there are some critical relationships unlike a stamped AK that has a cast trunion or the AR which locks on the barrel extention. This also means that whereas AK, AR and pistol receivers/frames can be used un-heat treated, on the FAL it needs to be done correctly which is not a torch/bucket of water/oil operation.

What kind of tooling is required?

Tooling and fixturing are likely to require several custom made items.

How long did it take?

Can't answer that one since no one claims to have completed one. The fact a machinist is asking this is of some concern.

I'm new to this type of rifle, matter of fact I'm absolutely clueless about the FAL, so any help is appreciated.

Wouldn't it be good for this fellow to take a good hard look at the FAL receiver before he gets his hopes up too high. He is "clueless" as to the FAL by his own admission.

Metallurgy is simple, 4140 ordnance steel. Don't know what tannery's castings are.

So, fellows, I too would like to see someone pull this off but I feel it is only fair to warn the fellow that it is:

a) going to cost a lot more than buying one (by the time you purchase/make fixtures, etc.)

b) require a set of prints that are not generally available (the ones out there including the ones on the auctions are incorrect) or reverse engineering of an existing receiver

My days of gung-ho youthful enthusiasm have been tempered by experience (including failures). I think my comments in response to madmax are responsible information sharing. So, how many receivers for firearms have the cheerleaders amongst us manufactured? Post pictures so we can see your handiwork. I already have on 19kilo's thread on Maadi furniture.

BRM308
April 10, 2002, 00:38
Um. Ah. Ya see(embarassed cough)Just one. An RPK reciever with the bulges for the front trunion.And a couple of 1/2 finished Ar 15 raw forgings.
I sort of look at stuff like this as a challenge to my machining skills.
(Gotta get ahold of William at the Tannery Shop)

blackbird
April 10, 2002, 02:16
BRM - Did you make the RPK receiver from scratch or modify a commercial one. Reason I ask is that I have been experimenting with the thicker sheetmetal for the RPK and it is a different animal (growls a lot louder) than the AKM. Also, where did you find a kit. I hear InterOrdnance's are really poor.

Can you post a pic?

Thanks.

Templator
April 10, 2002, 02:18
,... you'll go crazy,..

blackbird
April 10, 2002, 02:29
Templator....

,... you'll go crazy,..

Are you quoting song lyrics? If so, could you please fill in the blank for us old fogeys? Who? When?

If not...

what in God's green earth you talkin' about?

Templator
April 10, 2002, 02:36
lol,.. just responding to those folks who are contemplating milling a FAL receiver from a blank, blackbird,... you and others (who should know better) seem to want to indicate that it's a possibility,.. well,.. yeah!,.. it's entirely possible to take a clump of steel,.. smack it down into a Kurt angle lock vise with a Lixie dead blow hammer,... put an end mill in the spindle,.. then, after an orgasm of chip throwing, you blow every thing off,.. and low and behold!,.. what to my wondering eyes should appear,.. but a FAL receiver with a logo of gear!!

But you and me both know that it ain't gonna happen,... now do we?

[ April 10, 2002: Message edited by: Templator ]

blackbird
April 10, 2002, 02:47
Templator: You've got me confused with someone else. If you read my posts I am not encouraging this fellow to waste his time.

Templator
April 10, 2002, 02:50
oh,... well,... I liked my little poem anyway,...

By the way,.. you do good woodworking, blackbird,...that FAL you built is a beauty.

blackbird
April 10, 2002, 02:55
Thank you for the kind words.

mwolfe82
April 10, 2002, 09:26
Hey just wondering Blackbird how complex is the finishing required of the ar-15 castings? Was contemplating try my had at finishing one.

blackbird
April 10, 2002, 13:47
Not too complicated but precision alignment of the holes is critical for troublefree operation. Tannery and others rent or sell a jig to insure everything goes into the right place. I wouldn't try to do this in the average shop without that jig.

I had plans and DRO (digital readouts) on my mill so once I squared up and supported the castings, I could move to the hole locations and center drill (a short stubby super-rigid little drill that stays on center), followed by the right size drill. The DRO eliminated any backlash induced error.

If I did another I would make, rent or buy the jig. It would make it quicker and less prone to error.

[ April 10, 2002: Message edited by: blackbird ]

W.E.G.
April 10, 2002, 14:21
Originally posted by Templator:
<STRONG>...after an orgasm of chip throwing, you blow every thing off,.. and low and behold!,.. what to my wondering eyes should appear,.. but a FAL receiver with a logo of gear!!</STRONG>

Cool! Maybe we can get somebody to make a metal stencil for the gear logo. I'm pretty good with an electric pencil. My Dremel is actually a Sears knock-off. But my electric pencil is a REAL DREMEL!

Group-buy for the gear stencil???

"Ey mon' don'cha know, dees ees da early model prototype Gear model. On'y few made, very valuable. I t'ink you should buy it, hurry."

BRM308
April 10, 2002, 15:19
Blackbird. I made it fom scratch. I built a bending die for my 20 ton press and used .050 4140 from Aircraft spruce and specialty.The dies for the bulges were milled and then used on the twenty ton press. For the design I just copied an AK reciever. Some of the pictures are at AK 47.net in their BIY archives. Tonight I'm going to weld on the rails.
Tmplar. I didn't mean to flame you, but I've seen some pretty impressive stuff made in basement shops. A few years ago I attempted to make a FAL reciever out of a solid billet and gave up, but now you can order a casting from the tannery shop that has a lot of the finished profile done. Say a 30% casting. No rails. A unfinished barrel hole and the magazine well is onlt roughed out. There are no LS holes etc. but the material is definately there. At 40 bucks a pop worth a try.

wallpep
April 10, 2002, 16:06
Sorry, I haven't seen this board for a couple of days. I've been doing my other project, an AR15 lower from a Les Baer broached forging. I've found it to be pretty simple overall (my first attempt was a Tannery Lower and it works great). The hardest part has been making fixtures, I want to do more, as do some friends, so if I can just slap a fixture on the mill and go so much the better.
But back to the FAL, the closest I've been to one was pictures until today. My tapco kit showed up so I know sort of how it looks. Next week I'll go and pick up a new upper so I can see how it all goes together, then I'll definately know how hard it is to make one. More than likely I'll try it even if it does look impossible, I figure having two won't hurt (the heavy barrels look pretty neat). When I start I'll definately take pictures and notes, maybe even write a book HAHA. Thanks for the feedback and input. :D

BRM308
April 10, 2002, 22:08
Madmax. I f you need an FAL print let me know.I don't know how accurate it is, but its a starting point.

blackbird
April 11, 2002, 02:39
Originally posted by BRM308:
<STRONG>Blackbird. I made it fom scratch. I built a bending die for my 20 ton press and used .050 4140 from Aircraft spruce and specialty.The dies for the bulges were milled and then used on the twenty ton press.
</STRONG>

Same here on the '74 that I posted a picture of. Same source for the 4130 as well.

Receiver #1: Used "Dr. Strangelove's" CAD blueprints from ak47.net which turned out to be wrong in length and height. The top cover missed the rear sight block notch by almost .125" in length and the buttstock/handguards were too loose.

Receiver #2: Corrected the dimensions. Got in a little of a hurry and chose to gas weld the rails (using small holes on the receiver walls). Mistake! Distorted the receiver sides. Made a homebuilt spot welder until I can find a commercial unit that can squeeze in there. Used a PIC MCU to give me time control on the "spot welder".

Receiver #3 met its untimely demise when the press slipped while installing the center "spreader" rivet. Steel rivets are a bugger bear!

Receiver #4 is what is on the rifle. I got lucky with the rivets.

Next time I'll use/modify an Ohio Ordinance receiver. Cheaper and probably less frustrating. The '74 receiver is virtually identical to the '47 as I found out too late into this process.

The good news the the rifle shot the first time and every time since. Five hundred rounds so far without a failure. Looks like everything ended up aligned as it should. A lot of "basement projects" don't seem to work quite this way. I'll chalk it up to painful double and triple measuring and a healthy dose of luck.

So... "Um. Ah. Ya see(embarassed cough)Just one"... you really haven't finished a home built receiver yet. You have some challenges ahead... ;)


PS - Whose RPK kit?

[ April 11, 2002: Message edited by: blackbird ]

glenplumridge
April 11, 2002, 03:30
Have done 3. 1 from mild steel to prove feasable, 2 from solid block of 4140. Took about 20 hours each, use slot cutter for rail grooves and grind your own tool for cocking handle slots, use the locking shoulder hole for reference dimensions. After all someone built the very first FAL from scratch, didn't they.

blackbird
April 11, 2002, 04:10
slr.oz:

Would love to see them!

Did you stop at Type 3 or did you go all the way for the Type 1 or 2 cuts? How'd you handle the undercuts at the front for the topcover? Did you turn the barrel threads or use a tap? Have any pictures? What markings did you apply if any? Was this on manual or CNC equipment? Whose plans did you reference?

Since you are the first I have heard of, I am very curious.

BRM308
April 11, 2002, 09:44
slr oz Post pictures please!

Blackbird. Yeah. It took me 4 tries before I got an acceptable reciever. I screwed it together.

blackbird
April 11, 2002, 11:56
BRM:

Could you post some pix? I could not do the screws (unless I completely ignored the original rivet locations) because the holes in the Bulgarian kit were already too big for #10's and the heads on #12 button heads were way too big.

Last try.... whose RPK kit?

BRM308
April 11, 2002, 14:34
I'll see what I can do about pics. It was an IO kit. Suprisingly, in good shape.

blackbird
April 11, 2002, 16:28
Originally posted by BRM308:
<STRONG>I'll see what I can do about pics. It was an IO kit. Suprisingly, in good shape.</STRONG>

Wow! A decent IO RPK? Consider yourself the luckyest gunowner alive! You did look in the barrel, didn't you?

Would love to see the pics. Did you dimple the sides of the magwell or put in plates?

cc48510
April 11, 2002, 16:31
How hard would it be to make a dummy receiver from one of these ? It doesn't need to meet tolerances since it won't be used on a real gun, correct ?

I would need to have the following. How hard would they be to do ?

1) Barrel Hole with proper threading. Doesn't have to clock worth shit as long as it looks fine.

2) Gas Tube hole.

3) Magazine Well.

4) Charging Handle Slot.

5) Holes cut to attach Lower (Take Down Pin, etc...)

6) Room to fit the Bolt and Bolt Carrier in place, but not enough to allow the gun to chamber a round.

blackbird
April 11, 2002, 16:41
cc: You are a FAL/AR guy right? Reason I am asking is that Kalashnikovs variants don't have many of the the features you ask about. I would imagine that the work to make a dummy is just slightly less than making a real one. You can probably leave out the lower rails but then you cant work the charge handle or it will get twisted outside the trunion and not go back in until you manually set it horizontal.

You will still have to bend the sheetmetal, drill it, mill the openings and rails, fit the trunions, rivet or screw them, etc.

glenplumridge
April 12, 2002, 01:07
To those interested, it was inch style recievers.The topcover over hang was TIG welded after machining as was the feed ramp then filed to shape. The ejector is removable, secured by a recessed grub screw and the mag catch pin, barrel was threaded on a lathe to match tap on hand. Milling was done on an old bridgeport with heaps of backlash which made it a bit nervewracking. Barrel then headspaced when reciever finished and the gas block also hand made and positioned. Unfortunatly I don't have the ability or the equipment to post pic's but will offer any advice to those wishing to have a go at scratch build. The design was reverse engineered as no plans are available at my location.

BRM308
April 12, 2002, 10:45
Blackbird. I said good kit and that is what the barrel looks like.Barrel was bright some light pitting.It was well used but everything refinished alright. When I shoot it I'll let you know.Believe me I know I got lucky.

cc48510
April 12, 2002, 11:40
Actually, I was an AR Guy. But, I am saving up for my first FAL. I was actually referring to the FAL Type Receivers (I just missed the last few posts in RE: Kalashnikovs). I really don't know much about AK Receivers.

Originally posted by blackbird:
<STRONG>cc: You are a FAL/AR guy right? Reason I am asking is that Kalashnikovs variants don't have many of the the features you ask about. I would imagine that the work to make a dummy is just slightly less than making a real one. You can probably leave out the lower rails but then you cant work the charge handle or it will get twisted outside the trunion and not go back in until you manually set it horizontal.

You will still have to bend the sheetmetal, drill it, mill the openings and rails, fit the trunions, rivet or screw them, etc.</STRONG>

blackbird
April 12, 2002, 13:59
Originally posted by slr.oz:
<STRONG>The ejector is removable, secured by a recessed grub screw and the mag catch pin, barrel was threaded on a lathe to match tap on hand. </STRONG>

Did you make the whole gun from scratch? Most of the kits we get here in the USA (is "oz" in your name for Aussieland?) have the ejector block and gas block included so some of the items you mention would not be part of "making a receiver" to most of these fellows. Did you not have access to the ejector block with the bolt holdopen and mag catch?

Thanks.

Templator
April 13, 2002, 11:56
slr,..I'm sure that many on here would like to see your rifle. Sounds like you did quite a bit of work on it. You're the first person that I know of who has fabricated a receiver from scratch.

Yours is definitely a project which should be photographed and posted. Borrow a digital camera if you don't have one and get us a pic.

Thanks,...

Blade
April 14, 2002, 12:51
The FAL reciever is possible but not really cost effective if you look at the price of an IMBEL. The cutters I bought to do the job were almost the cost of an IMBEL Type 3.

I built one at work on a Lagun mill which is really just a Bridgeport copy. I used 4140 barstock. I have been planning to get one of the Tannery Shop castings to check out but just haven`t got to it yet. I will get that taken care of and I also want to get a copy of his prints to compare to mine along with the 1911 prints.

I used prints I got from a machinst that built one for a L1A1 kit when those kits first came out. I wouldn`t claim they are an exact match for Steyr prints but they do work. I have started a computer 3D drawing in a Uni-Graphics cad system but it isn`t complete yet.

edit: Another thought , the reciever must be put in the mill vertical to cut one surface and it will probably take a full size mill to have enought vertical clearance. I have never used one of the mini-mills but just by looking at them it would be tough to fit.

I went to Knob creek yesterday and the FNs from DS Arms were easily the best looking rifles there.

[ April 14, 2002: Message edited by: EMDII ]