View Full Version : Suggestions needed for 1911 frame rail cutting

May 19, 2001, 11:35 AM
I think most people have probably heard about Tannery Shop (www.tanneryshopinc.homestead.com) selling 80% receivers, he sells receivers that arent yet legally a gun (as they require lots of work to finish) and ships them right to your door. You finish the gun yourself (No one may work on the gun until it is complete other than you) and get to choose a custom serial number. Tannery's latest offering is a 1911 frame with the frame rails uncomplete. Here is a picture:
I was thinking of using a Brownell's 1911 auto slide/frame rail file (stock number 080-753-000) to finish the rails. Would this file do the job? Anyone have any suggestions on alternate methods? Milling is not really an option right now.


John Lawson
May 19, 2001, 01:54 PM
Ho yeah! You certainly COULD do it with the file. After all the Paki's in the Khyber pass did it with nothing more than a file for a long, long time.

May 19, 2001, 02:05 PM
I don't see ANY rails at all? the only way to get rails cut is with a smith who has all. I've used that file to fit a
slide, and it will take alot of metal off fast, but where
the heck would you start?milling is the only option, then you can fit slide with stones or files.

May 19, 2001, 02:23 PM
Because the frame is an 80% receiver, it cant have any rails at all when its sold, or it would be a firearm and require a NICS check and Form 4473.
I was thinking about making a jig using two peices of 1/4" plate steel, and indexing off the holes in the frame and running bolts thru the holes to hold the jig in place while I work the file. I cant mill stuff easily (I can do really light work, such as aluminum, using my 5/8" chuck drill press and its slide table, but i dont want to burn the bearings milling steel if I can avoid it, which bit would I use anyway? Does Brownell's have it?), but the dress press can drill thru plate steel and I also have cutting saws to shape the jig. If I made the jig, would the file method be possible?


May 19, 2001, 05:39 PM
wheres George Stringer?I wouldn't even try this job, had
enough trouble fitting finished slide to frame.one slip and
you'll have a chunk of worthless steel. someone else has to
give you info,its beyond my ability.

May 19, 2001, 06:50 PM
I have the machinists blueprints in front of me and I would say do it with a woodruff keyway cutter after putting it in a mill vise and dial indicating it. Because it will do it evenly on both sides and a-lot faster to boot.
That is my opinion though. Filing can be very imprecise let alone doing two sides the same is not too easy at all. But if you want to do it more power to you.

May 19, 2001, 07:25 PM
Teufelmann55: Ah, thanks for the idea. I assume I'd want a 3/32" cutter (a 3mm one would be ideal, but i sorta doubt I will be able to get one), and then hand-fit the slide and the frame together?


John Lawson
May 20, 2001, 08:27 AM
Modern "gunsmiths" are machinists, pure and simple. In the far off days of the 1940's, an apprentice was given a task like this and a set of files. If he couldn't accomplish the task, he was automatically called a ribbon clerk.
Any gunsmith who CANNOT accomplish this, is certainly not of the old school.
It was done this way: give the part a coating of layout blue (also called toolmaker's ink) and carefully lay out your lines with a very sharp scriber. Then you apply a straight edge guide for the file (one was deemed enough in those ancient days.) This was usually a hardened piece of tool steel. Note that it was a major operation to harden the guide without warping it.
Then the guide was clamped to the part SOLIDLY with toolmaker's clamps. The part (grip frame, in this case) would be solidly attached to the workbench or vise. You begin with short strokes, laying the file against the guide. Soon, the cut will be deep enough to guide the file evenly against the guide piece.
The first cut would be narrower than the slide rail, in this case, and the depth kept shallow. (The file has to be guided by the left hand as the right hand pushes it, making an even, parallel cut.) Then the other side is done. After this, the fitting phase begins in the normal fashion.
Before this kind of test, the "old master" called you "Mr. X" If you accomplished your task successfully, you were Mr. X, the Gunsmith." No higher compliment could be paid to an apprentice who had proven himself a worthy journeyman.
Today, any kid could do the job with minimum instruction. Clamp the part, align the cutter and go!
And, for this, I say: How many of you Misters could do this job as your long ago predecessors did it?
Is it "Progress" that we now depend on electronic readouts and special lead screws? Whatcha gonna do when the lights go out? (and, they will go out for the big time this Summer.) Think about it.
Boy, we have a bunch of (by their own admission) ribbon clerks hanging around here, don't we?

George Stringer
May 20, 2001, 09:31 AM
Kharn, as John said it can be done. You can get the dimensions you need from Kuhnhausen's books. He's right about something else too. Gunsmiths these days are machinists when it comes to something like this. If they aren't they find other jobs quickly. You just don't have the time. I make a lot of my own parts by hand but when I can cut them in a mill or a lathe that's how it's going to be done. How many folks would be willing to pay someone by the hour to file away at something like that? Is it a lost art? Maybe. Is there a need for it now? No. If I were you I'd have a local machinists mill the rails close and then finish it when you fit the slide to it. George

May 20, 2001, 10:39 AM
George: The ATF has ruled that only the owner may work on an 80% frame until it is functional (they used the test of able to fire a primer in the Maadi-Griffon case), once it can do that and the owner puts a serial number on it, it is treated as a normal firearm for purposes of gunsmithing. Obviously, a 1911 would not be able to ignite a primer without the frame rails done.

I'm probably going to take John's suggestion and do it by hand, I have a lot of spare time this summer and i would rather sit there and file away then burn out my drill press trying to cut the rails. I'll probably even make a jig out of the hardened plate, I could once, the plate and frame are clamped in place, run a drill bit thru the holes in the frame, and then bolt the plate to the frame. This way, if I bought more 80% frames, I could complete them easily.


May 20, 2001, 04:11 PM
Kharn, do you know if these 80% frames are forged or cast? I went to the site and they seem to specialize in castings, but they make no specific mention of the 1911 stuff being cast. Aren't forgings preferable to castings when it comes to handgun parts? Just axin'


May 20, 2001, 04:38 PM
They are cast steel or stainless steel. Forgings are preferred, but doesnt someone make complete 1911 castings? (Caspian?) With the right protective coating and enough lube, it should be fine.


E. BeauBeaux
May 21, 2001, 11:21 AM
Kharn, don't be discouraged. I have an email in to Brownell's in hopes of getting a file designed for this purpose. It can be done, and will be a better fit than factory as this way you can match the slide to the frame. I have the other 80% they offer and this will be easier than the AR project. Hang in and we'll get through in style.

May 21, 2001, 12:07 PM
E. BeauBeaux: Wont the Brownell's 1911 auto slide/frame rail file that I mentioned in my first post do the job? From the description it sounds like it would.


E. BeauBeaux
May 21, 2001, 01:22 PM
I looked at the same file in the catalog, it's for a final finish the way I understand it. Not wide enough for a one time cut. Maybe I miss read it [I'll recheck it tonight]. If I get an answer back form Brownell's I'll post it. Sent it last Thursday.

John Lawson
May 22, 2001, 12:45 PM
Congratulations, and my apologies! There are no ribbon clerks on this forum!
George is right about it being commercially implausible. However, once, when I was really sick with the flu, I got up when my wife went to work every day for several hours, toughed it out, and went out into the shop to work on a Popular Mechanics design for a boring head. By the time I was able to return to work for 8 hours, I had a boring head that I was not able to buy for financial reasons.
As my old jmentor used to say: "Poor people have poor ways."

George Stringer
May 22, 2001, 01:59 PM
Kharn, I just got off the phone with a compliance officer in the ATF. I had to call them on another matter and I asked him about your frame and having someone else cut the rails or whatever. What you said earlier about a ruling against that didn't make sense to me. Here's the deal: There is no ruling against you having a gunsmith or machinist cut the rails or do any other work to the frame. As long as they are doing it "under your direction" and not on a frame that belongs to them then they are not involved in manufacturing under the gun act. You are but as we all know you can do that as a private individual. So I'm back to my original recommendation that you have someone cut the rails in to say .005" oversize and then fit your slide to the frame. George

May 22, 2001, 02:04 PM
Whoa, that is a very good ruling for us, we (everyone on AR15.com's Build It Yourself forum) had kept to the "must finish it yourself" standard as to not run afoul of the ATF. I might just have to write a letter to the ATF to get this in writing, the guys on Ar15.com will be very happy to hear that.

Thanks for giving them a call,

May 23, 2001, 05:30 PM
Dlask Arms sells heat treated steel drop forged frames.
24.95 + shipping. I'm gonna try that out.


May 23, 2001, 09:58 PM
Kharn, thanks for turning me on to another great forum! If you know someone with a surface grinder, or don't mind paying a machine shop, just buy a file a little thicker than you need the rail slot to be and have them grind it to size. That way only the edge teeth will cut. And use a nice thick block to guide the file. An inch would be much easier to hold the file square and firmly against rather than the 1/4" you planned on using. And if you get that ATF compliance officer's ruling in writing, how about posting a scan somewhere.

gunbuilder, I'll bet you are the same "Rick" we know at AR15.com. If you decide to offer 80% forged 1911's from dlask I'll be your first customer. As with the AR forgings, the magazine well will be the problem spot for most do-it-yourselfer's, along with the horizontal and vertical slots for the trigger. But no sweat with your magical electric wire and trodes.

May 27, 2001, 08:09 PM
George Stringer, If the information about having rails cut
on the 1911 forgings by a machinist or smith are correct as
stated by the ATF, I would pay someone to do this for me.
I understand that the work must be done at my direction.

George Stringer
May 28, 2001, 07:54 AM
JP27, I'll e-mail you. George

May 30, 2001, 08:37 PM
Don't be bashful, use your slide table, nobody said that you have to take out all of the material at once. Use an end mill or keyway cutter and take out .010 at a time. This way you won't have to much vibration, you will have a straight cut to guide your finish work and you can stop short and finish with a file and stone.

May 30, 2001, 09:08 PM
My parents are going to order a milling machine for me, so I just have to wait until the mill arrives and then I could complete the rails with the mill. Where could i find a keyway cutter? I had a link on Grainger.com to one, but I lost it, and I cant find the cutter now.


May 31, 2001, 08:23 PM
Try http://www.mcmastercarr.com or J&L Industrial Supply. My personal choice for basic cutting tools is Mcmaster Carr, their prices are fair and they have it in stock 99.9% of the time. J&L has more specialized stuff and is a supplier for small machine shops.

June 4, 2001, 09:34 PM
A Woodruff Cutter should be no more than .120" wide.
What we in the shop I work in think is ideal for the dimensions is-the frame rails ideally about .120" +.0000" -.001" thick and the width of the rail cutouts in the slide itself. The cutout should also be about .120" high =+.0000 -.001 ideally (all dims. are for match fit with slides we use). All dimensions are before fitting the slide.

Frame _______ ____
Rail I .113"min .120"max thickness
_______I ____
Undercut of rail I .120" Ideal +.0000" height
I__ ____
*DIMENSIONS SOMETIMES VARY ON SLIDES SO PLEASE MEASURE SLIDE THAT YOU ARE GOING TO USE FOR ALL DIMS.!! Also measure twice and cut once!!!! Remember that the Dims. I give you are what we use and are not law-just what we have found to work for our particular needs.

June 4, 2001, 10:01 PM
Sorry about the confusion on my last post I tried to do a basic line drawing to show how it is supposed to look but the computer garbled it so I will try to figure out how to post it in a more intelligible manner.