Recutting hammer hooks

[shovelwrench]

While fitting a new barrel I discovered one of my hammer hooks is chipped. Its a Nowlin hammer, so I'd rather recut the hooks then replace it. I only plan on cutting enough off the hooks to clear the chip, then the same amount off the flat.

How do you guys indicate the hammer into the mill?

[log man]

Hey, I don't have a mill so can't give first hand advice, but laying a flat across the jaws shimmed on each side would be close. But I have run a mill and I probably would use an indicator on the flat. :)

Brownells is an amazing company, and would probably replace that hammer. They replaced two that did this, this one of a friends gun. No questions.


http://i472.photobucket.com/albums/rr85/logpics/20081111_2-1.jpg

LOG

[CDogg]

im actually thinking of ordering a bunch of internal and external parts of a 1911 that endures alot of stress for emergency purposes. In that way when something breaks, I dont gotta wait to order and get it before I could replace it. These parts have been discussed in another thread. Parts like the strut, hammer, slide stop all the springs, sear, disconnector and ecven the barrel bushing.

[shovelwrench]

Hey, I don't have a mill so can't give first hand advice, but laying a flat across the jaws shimmed on each side would be close. But I have run a mill and I probably would use an indicator on the flat. :)

Brownells is an amazing company, and would probably replace that hammer. They replaced two that did this, this one of a friends gun. No questions.




LOG

I had'nt thought of doin that way, That should work. I thought of trying an indicator on the flat, but even with the .0005 indicator I have, I feel like the surface is'nt large enough to get an accurate indication. I'll try your suggestion of shims under a parellel, then check with my indicator.

I'd consider returning it to Brownells but I hate to wait, when it'll only take a short time to cut it.

I probably won't get to it till this weekend, but I'll let you know how it works out.

Thanks

[Jerry Keefer]

shovelwrench

How do you guys indicate the hammer into the mill?
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Built an adjustable/repeatable fixture some years ago to hold the hammer.(and sear) It allows me to remove it and check the engagement angles and make adjustments if need be. The mill will work, but if you have access to a surface grinder, it's the only way to go.. I align the flats on an optical comparator.

If I could figure out photobucket, I'd send a picture or two...

Jerry

[shovelwrench]

shovelwrench

How do you guys indicate the hammer into the mill?
-------------------------------------------------------------------------
Built an adjustable/repeatable fixture some years ago to hold the hammer.(and sear) It allows me to remove it and check the engagement angles and make adjustments if need be. The mill will work, but if you have access to a surface grinder, it's the only way to go.. I align the flats on an optical comparator.

If I could figure out photobucket, I'd send a picture or two...

Jerry

Yeah,
I wish I had access to a surface grinder....

I wound up only having to take .002 from the mating surface of the hooks, and I took .003 off the flat (a little working room). The only way I have to check mating angles is with the pins in the frame and a magnifying glass.

Really I should have been keeping a closer eye on the hammer and sear in this gun, it was under a 2lb pull. 5,000+ rounds through it though.

Log,
I tried the shim idea, but could'nt hold it all in place, with pressure holding the hammer to the parallel (not much space in the jaws for my finger), and tighten it all up. I wound up just using the indicator, .0005, and kept adjusting till the needle did'nt move one bit..

Have'nt set it all on the pins yet to see, all should be well.

[Dave Berryhill]

Check out this post by Pete Single:
http://forums.1911forum.com/showthread.php?p=24382&#post24382
Scroll down to "Tip #1"

I've been using this method to cut the hammer hooks ever since I read this post years ago. I bought the horseshoe magnet and some .030 brass shim stock from MSC. The thickness of the shims isn't critical but using something non-magnetic makes it easier to set it up rather than steel shim stock. Using this particular magnet isn't critical either but it does have a nice square machined surface and it works well. Also pay attention to the climb milling instructions that he gives.

I also clamp the stone in my bench vise using rubber jaw pads and move the hammer back and forth along the stone like he suggests. It's much easier to keep the hammer square against the stone that way. I always have to do some de-burring of the edges after I machine the hammer but before final stoning of the hammer hooks.

It's not as nice as using a surface grinder but it's the next best thing.

[niemi24s]

Hi Dave:

Very interesting thread - thanx for posting a link to it.

FWIW, the angle between the hammer hooks and their adjacent flats works out to 86.00° from data on the Ordnance blueprints. [whoopie-ding! :D ]

Regards

[shovelwrench]

Thats thread is good reading material.

I'm gonna go ahead and order that magnet for future hammer work, and some brass shim stock.
My angle seems to be slightly captive, but made for a VERY crisp trigger.

Still waitin on some links before I get to shoot it again, its amazing the work one squib in a match will make for. I'm still wonderin if that did'nt have somethin to do with chipping my hammer.
http://i116.photobucket.com/albums/o2/shovelwrench/100_1500.jpg

[log man]

Ouch! The importance of the hook face being square to the flat is just to maintain the original angle as they are cut with an end mill that has straight sides. What's relative is where does the hook face point when extended towards the hammer pivot hole. Para and Kimber will intersect the center point, while most others, and good, will point to the top of the hole. The sear should always and is the original design, be neutral so it neither raises nor lowers the hammer. Geometrically this means a line through the sear pivot and touching the sear nose is square with the face. If the hammer hooks are like Para's old hammer the match is parallel, contrary to most this is not good, the sear slips out easy enough, but is dragging the whole way and and follow will begin as the pull approaches 2#. The hammer hooks face should point to the edge or slightly lower, but above the center point and have a radius on the tips that contact the sear about .002"-.003", just a deburr and smooth. And if they are about .020" in length or less they will land right on top of the sear face, good, now when the trigger is pulled the sear will not move until the pull weight is achieved and will snap out crisply. If the hammer hooks should be long and pass the sear face the that would be captive, but if they land on top then it is aggressive.

With what I've written in mind, study the two configurations.

http://i472.photobucket.com/albums/rr85/logpics/20081217_2.jpg

http://i472.photobucket.com/albums/rr85/logpics/20081212_3.jpg

http://i472.photobucket.com/albums/rr85/logpics/20081218_2.jpg

LOG

[niemi24s]

. . .its amazing the work one squib in a match will make for.http://i116.photobucket.com/albums/o2/shovelwrench/100_1500.jpgThanx for posting the pic.

Looks like, if not for the bushing & slide, you'd have a genuine "banana peel".

Regards

[shovelwrench]

Thanks Log,
I'm gonna do some more checkin on my angles befor I call it done.

Thanx for posting the pic.

Looks like, if not for the bushing & slide, you'd have a genuine "banana peel".

Regards

Yeah, PPC rapid fire does'nt lend time for checkin if it made it out of the barrel. Hopefully the "hard fit" of the new barrel will take this one holer @ 25 to a place of 50yd accurate.

[Dave Berryhill]

...its amazing the work one squib in a match will make for. I'm still wonderin if that did'nt have somethin to do with chipping my hammer.

I don't know about the hammer but it certainly didn't help the barrel. Ouch!