A pair of 1911s that I built from Sarco kits, the parts for the most part are o.k, the extractors suck, but the rest are good, but I am having trouble with the slide stops on both of them. I can not release the slide with thumb pressure, it takes both thumbs. I am going to replace them when I can with extended stops. Until then, how do I get these to work right, where do I file?
Are you trying to lower the slide stop with a empty magazine in the pistol?
If so remove mag and try again.
If not, check the angle of engagement between the slide stop and the slide - it should have neutral or negative engagement. Also, if there's a slot or dimple at the back of the slide stop for the plunger to engage make sure it's not too deep, or sharp sided (and the plunger isn't too pointed).
Try it with out a recoil spring, normally there should be some slide overtravel past the slide stop notch. If there isn't, you are at coil bind or something is long.
Your're on the right track, refacing the end of the slide stop is easy to do and I do it all the time to get one to drop easier or harder depending on what is necessary. As long as you think about it before you file you should be good to go. Usually the angle on your slide stop is about neutral you just need to file an angle so that is can slip down easier, Just putting in a degree or two is all that is usually needed.
I filed just a tad off the end of the stop, then stoned it, did it to both, now they work great. Firm but easy to operate.