Thumb Safety - how to fit?

[Tom in Ohio]

I'm thinking that I would like to replace my stock Springer ambi-safety with a single thumb safety - extended tactical type. My question is which brand should I get? I am concerned about how it is manufactured because I use a high-hand hold where I rest my thumb on the safety while firing and I don't want it to snap off. I also want one that I can install myself. I am not a gunsmith, but I can get by with a file. What kind of hand fitting is usually required and is it something an amateur can handle? If anyone has knowledge on how the various makers stack up please let me know. Thanks.

[stans]

King's Gunworks is one of the older names in the business and they make good parts. Wilson and Ed Brown are also very good. If you know what you are doing and are handy with a file (no Dremel), then you should be able to handle this job. Thumb safeties rarely drop in, the surface that blocks the sear almost always needs to be adjusted.

[1911Tuner]

Like stans said, it's not a major operation, but it does take a little time. Helps to be able to see what you're doin' too.

Assemble the gun without the grip safety so you can see exactly what and how much to file. It'll come down to a one light stroke and check, etc. until you see how it pregresses. Removing the plunger assembly from the tube
will make it go faster, since you won't have to mess with that when you try it to check the fit.

One thing...The safety lug has three identical-looking points. Only one is the right one, so make sure you've identified it. Many first-time fitters don't,
and cut the wrong one. Try to maintain the radius and blend it. Leaving a sharp corner can lead to a crack. I suggest using a round needle file after the point is right.

[Tom in Ohio]

Thanks for the advice. I ordered the Ed Brown safety last night. If I run into any trouble installing it I'll probably put up another post. Thanks.

[Tom in Ohio]

Well, I gave it a try and I think I ruined the thumb safety. I got it to go in all the way after some careful filing of the corner of the lug where it struck the sear and everything seemed OK. Once it was in the frame and just fit past the sear, I couldn't get the safety to engage (move up) so I kept filing a little more at a time. I wasn't sure exactly where to file to make this happen, so I kept filing at the same point on the lug I had been filing to get the safety to clear the sear. Eventually, I took off enough metal to where I could see daylight between the safety lug and the sear and still it wouldn't move up all the way. I then discovered that it wouldn't move down all the way either. I could not see where the safety was hanging up. It wasn't being blocked by the sear or the hammer and I had removed the plunger. Eventually, I figured it out that the cut on the safety lug where it engages the frame was not fitted properly. When I removed all the other parts: hammer, sear, disconnect; the safety would not move up or down fully in the frame. The frame was binding in the cut on the safety lug.

So, now that I have parted with $30 on one thumb safety, I would like to try again and do it right. Does anyone know where I can find instructions with pictures and better step by step instructions than those provided by Ed Brown?

Thanks.

[1911Tuner]

Tom...It looks like you've fallen victim to that age-old (Machine Age) bane known as "Tolerance Stack." The frame is at the high end of tolerance...The frame slot in the safety lug is at the low end...and there's a couple thousandths inch worth of NO-GO. Rare to happen with safeties, but it does happen occasionally.

Only thing to do is get another one and start over. King's makes a good safety, but I don't think the instructions cover that particular glitch. Measure the slot width in the new one and compare with the old one...
and adjust as necessary. The safety should move a little, even if the block point needs fitting...so you shlould be able to tell when you've got it right.
Don't cut the slot so wide that it lets the safety walk in and out of the frame past just touching by more than a whisker's breadth.

If it's any consolation, I nearly killed one about 2 years ago because of the same issue that you had...Mine wass because of a slight taper in the slot, so the safety moved...it just stopped short. I caught it just in time, but JUST in time to let me swage the point enough to block the safety.

On the plus side, you gained a little knowledge and understand how tolerance stacking can bring on a Murphy Moment. Happens to us all. If a smith tells you that he's never killed a part...he's either lyin', or he's only worked on one or two guns.

[Tom in Ohio]

Thanks, I guess I'll just have to consider it a $30 gunsmithing lesson.

[1911Tuner]

Thanks, I guess I'll just have to consider it a $30 gunsmithing lesson.

Yep. On the next one, remove the hammer, sear, and disconnect to make sure the slot will fit the frame. Chances are that it will.
If you have to fit the slot, take at least half from the pad side
of the slot. Keeps the safety from walkin' in and out.

[SW1911SC]

QUOTE:

Eventually, I figured it out that the cut on the safety lug where it engages the frame was not fitted properly. When I removed all the other parts: hammer, sear, disconnect; the safety would not move up or down fully in the frame. The frame was binding in the cut on the safety lug.


REPLY:

I think you can still use that Ed Brown safety. The Ed Brown thumb
safety needs a little filed off where it engages the frame. That's how
they are made. Once you relieve that area, the safety will have more
travel and you can then refit it to the sear.