FAL from scratch

[LT250R]

OK, this is my first post to this site. Also I am new to FAL's, never even had one in my hands but have become very interested in building one. Has anyone built one from one of the casting sold by The Tannery Shop. I am a machinist and have access to several lathes and mills including CNC macnines. I would like to know about any special machinig problems or tooling required to complete one of these.

[W.E.G.]

To my knowledge, nobody has successfully created a working FAL from one of the castings. I may be possible. But, so far no reports.

[skfullgun]

O.K., now you're talking about something about which I know nothing (not very hard to find a subject like that!). But....you sure as hell got my attention! :D

Keep us informed.

[rwwje]

Hell, there's a couple of manufacturer's that more than a few people would say still haven't figured out how to do yet (even though they have made and sold thousands). :D

[Upside Down @ 100 MPH]

I would say forget it. But on the other hand if you're the determined type, have the skills, and lots of time then go for it.

[blackbird]

First step would be to find out exactly what material the casting is made of. Their website does not specify. Whatever it is, one would have to consider the strength of the material, fatigue resistance (i.e. no aluminum) and ability to heat treat after the machining is done. Note that the FAL receiver from Tannery is not an 80% but a 0% which essentially means you have somewhat of the outside shape. I am not sure if it is a cored casting but if it is not, that is a lot of roughing to be done (maybe enough that billet 4140 might not be a bad idea). I saw a post here that stated that over 400 operations were required to take a billet to finished receiver. I cannot attest to the veracity of that number but in any case, the number is pretty significant. Add to this the fact that you will have to start by making quite a bit of fixturing and tooling and you start to get the idea that it might be a lot of trouble and expense for just a few receivers.

Another factor might be the unavailability of accurate plans. I sat down with a dial caliper and micrometer once to CAD the receiver but gave up after a few hours and slow progress. If anyone ever finds any accurate ones, please post it here.

If you do persist and have some success, let me know. I have equipment similar to yours including some fancy VMC's but decided the receivers were a bargain at anything under $400. Perhaps you'll discover some shortcut that I overlooked.

[ March 04, 2002: Message edited by: blackbird ]

[medicmike]

I would love to see someone do that and come back with a report that it was sucessful and easy ;) It looks to me that there are a LOT of machine operations and some pretty critical dimentions there. The only way find out is to go for it! Then give us a full report :D If it is pretty straightforeward I would be willing to give it a shot but I don't think I am that good a machinist and my equipment is pretty basic.

[Templator]

I'm a toolmaker and I wouldn't try it. I'm sure that it's possible, but it's going to be quite a bit more involved than you might think. The first obstacle that you'd have to overcome is the fixturing to hold it in the various positions necessary to perform the machining. All 6 sides of a FAL receiver have intricate machining,.. all 6 sides have to be machined relative to the other 5,.. and actually, if you count the inner breach face,. there's 7 sides to be machined. Additionally, some special cutters would have to be obtained to make some of the cuts. Check out the charging handle slot. I can think of no way to cut that without using some type of small, delicate (expensive) slitting saw.

People who tool up to produce receivers to sell figure in tooling costs as part of the overall picture,.. but tooling up to make just 1 is going to be much more trouble than a person is typically going to be willing to do.

lol,... I'll put it this way,.. if you ever did machine a FAL receiver out of a rough blank,..you'd put it in a hermetically sealed glass case and display it on the mantle.

[ March 04, 2002: Message edited by: Templator ]

[blackbird]

Originally posted by Templator:
<STRONG>Check out the charging handle slot. I can think of no way to cut that without using some type of small, delicate (expensive) slitting saw."
</STRONG>

Woodruff keyseat cutter (MSC $28) or, if you have one, are old enough to remember how to do a setup, and can grind the tool, a shaper?

Originally posted by Templator:
<STRONG>
"sealed glass case and display it on the mantle."
</STRONG>

LOL (but probably correct)!

:D

[Templator]

Of course a woodruff key cutter type of tool is the first thing that comes to mind for cutting a slot like that,.. but I can't recall ever seeing one with a face thickness that was that small. I don't have any measuring tools with me right now,.. but my calibrated eyeball tells me that the slot is somewhere in the neighborhood of .040". Does MSC offer them that thin?

[blackbird]

.250 diameter, .0156 Part # 07006273
.250 diameter, .0312 Part # 07006281
.250 diameter, .0469 Part # 07006299

and so on...

[Razielas]

thread it for where you expect the barrell to go in and then make a male piece. Chuck that in you indexer and make a center at the other end of the blank and use a center and when necessary use a machinist jack, I am fairlyy confident that is all the jig that you will need. Key slot cutter would be the only way to go for inside rails. look up a guy Roderus custom on the net and see the Bootiful Job he did on M1911 rails best I've ever seen from any manufacturer. YOu might have to employ an EDM to make the slots for the cover.
JOhn

[withergyld]

FWIW I saw a set of CAD drawing for FAL receivers at gunbroker.com for $9.99 Buy it now.

How good are they??? Won't know until someone tries them. Fal receiver diagram (http://www.gunbroker.com/auction/ViewItem.asp?Item=3297361)

[blackbird]

Well, here (http://www.williamsarms.com/fncnc.htm) is how Williams (who is probably a very bad example) does it. Please note that they are using a very heavy Kurt vise with what appears to be a series of custom jaws (to prevent crushing the charging handle slot, etc). The do have a non-vise jig on the horizontal mill for the barrel threading. Those VMC's are also loaded to the gills with tools. From analyzing the design a lot of those will have to be purchased for this job.

Most important, William's setup is to machine 7075! I would imagine that 4140 would require even more robust support. Somehow I don't see and indexing head/tailstock providing that.

Just my opinion...

withergyld: I believe I've seen the ones "aliciaandcharles" are offering and they are incomplete. This is an idea many of acquaintances in the tool & die trade have toyed about for a long time and one of them purchased "two 18x24 CAD drawn sheets" a few months back.

[ March 04, 2002: Message edited by: blackbird ]

[withergyld]

I saw them there and was curious to see how good they were, and now we know.