Just wondering what is involved. I've completely taken apart my 1911 several times and was wondering what is involved in fitting a non-ambi safety.
Which non ambi safety is good to get

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nice pic, that's what I needed. Thanks

Buy 1 or 2 cheap ones safeties to learn on first.  No sense ruining a perfectly nice Brown thumb safety.  I ruined two thumb safeties learning this, but they were only $20 MIM parts so I wasn't out that much.  

Also, this needs to be a near interference fit between the sear and the stud on the safety.  It should be a pretty tight fit.

Checkpoint: when you think you're close, install the slide w/o the barrel or guiderod.  Engage the safety.  It should require effort to get it fully upward (thus, the stud on the safety is making good contact with the sear).

Checkpoint: with pistol fully assembled, apply thumb safety.  Grip pistol in firing grip to release grip safety, then pull trigger very hard.  Now remove finger from trigger and disengage thumb safety.  If hammer falls to 1/2 cock, you took too much material off when fitting the thumb safety, which allows the sear to move when the safety is engaged and the trigger is pulled.  You now have a ruined thumb safety and a gun that will not function safely.

Good luck!

SF

now I'm getting nervous
Maybe I should bring this to a competent 1911 smith since I've never done fitting before.
I rebuilt my share of machinery but never a gun

I fitted an ambi safety this summer for the first time.  Just go very slow and take your time.  The only instructions I had was looking at how the old safety fit.  All I had was a set of hand files at the time too.  It was probably good I didn't have the dremel yet.

Like MartinMayhem writes, using backwards engineering can give you a ballpark idea on where to file and how much.

I used dial calipers to measure the distance from the pin on the thumb safety to the point on the stuf where it contacts the sear.  Comparing the new and old safeties gives an idea of how much material you have to remove.

Don't remove too much too fast!  Check it often once you are getting close (every 5 file strokes).  A dry erase pen might prove useful to see exacly where on the stud it's contacting the sear as engages and disengages (you gotta file it flat, not crooked).

You'll be surprised at how quckly a file can work, especially when you're talking about only removing 5 or 10 thousandth's of an inch.

Remember, you are striving too leave a little too much metal, not too little (too little ruins the safety, unless you can build it up again by welding it).

Using safe-side file would be good.

Also know that down the road if you change the sear, you'll probably need to refit the old safety or buy a new one and fit that.  If you anticipate using another sear or having a trigger job done (much, much more involved, but fun and rewarding once you know how), fit the thumb safety AFTER the sear is the way you want it.

SF

Get the kuhnhausen books.
Where are you in the state? I could help you out with this.

Quoted: Get the kuhnhausen books. Where are you in the state? I could help you out with this.

SE MN near Rochester

Nope, I haven't done this yet. I may let my local smith do it since I'm too retarded and impatient.

Quoted: I'd sure appreciate any advice you (or anyone else!) can give me. Thanks, Mark

I had a gunsmith give me a great sounding pointer the other day on thumbsafeties.  Take the inside in, clean off the blue and add sharpie marker, insert into gun, tap lightly to knock off the sharpie where it makes contact, and the section where the marker is removed is the area you need to file down.  Sounds a whole lot better than my way of test fitting, removing a little material, test fitting, etc........

twonami, I've fitted a few of my own...it's not hard if you're not too drunk

Really, I just paid close attention to what would move and what wouldn't, and very gently broke out a dremel and bought things down a notch. Constant checking and constant fitting/cleaning, and you should have a perfectly fit thumb safety inside of 10 minutes...

The one I fit to my Colt is so nice, it almost doesn't budge at all when the hammer's down. (Try flipping your safety on when the hammer's down...there's a good chance it comes up enough to block the slide from being pulled back...)

When in doubt, buy two; one to work on, and if that gets flubbed, go slower on the other

YMMV, I am not a gunsmith, yadda yadda yadda..

The last few thousandths are more safely removed with a stone than a file (in your hand, no power tool required).  Even a smooth cut file can remove metal to quickly.

Quoted: Here's the best of the dumb questions... Where do I buy this "stone" of which you speak?   Seriously, can I go pick on up at Home Depot, or should I be ordering something from Brownell's.  Same question for the file I guess, because all my hand file are pretty big.  Should I pick up some special set of small files? Thanks!

Brownell's.

www.brownells.com/aspx/ns/store/ProductDetail.aspx?p=9618&title=INDIA+STONES

I like the 657-010-034 and 657-070-723.  The first one is a good general purpose stone for fast metal removal.  For polishing, the hard arkansas stones do a good job and aren't too expensive.