Hardened/Hardish Steel to Make a Part

[Johnm1]

I'm researching the feasability of shaping a part to replace a half cock notch on a hammer and attaching it mechanically and silver soldering it in place when fitted. The part is small and would be fabricated from a piece of stock approximately 0.25" wide x 0.15" tall x 0.5" long.

Almost all of the surfaces would be sliding surfaces and the half cock notch is more of a 'hook' arrangement. So it doesn't need to be sear surface hard. But it shouldn't be soft either. I am not touching the full cock notch. Consider I'll be whittling this by hand with very little machinery to help. I can get rough shapes using a grinder and roto tools. But final dimensioning will be by hand with a file and stone. Sort of cave man tools. I have the patience to whittle and shape. Not sure I have the talent though.

So what are my options for material and what are the sources?

FYI - here is a smaller version of the hammer. The part would be from the marker lone down.



FYI - 3 failures aadding weld material and shaping in place. But, depending on if this is even feasible, I may have to try a 4th or 5th time.

 

[Hugger-4641]

I would probably go with a piece of 1084 or 1095, weld it , shape it, then heat treat it.

 

[Johnm1]

I would probably go with a piece of 1084 or 1095, weld it , shape it, then heat treat it.

Where does one get little bits of steel?

 

[755]

Where does one get little bits of steel?

i am a kifemaker if you have any in your area they probably have pieces like you need laying around from cutting out blanks

 

[Steve762us]

I'm not a machinist.

How about a pin, vs surface application?

Fab your half-cock hook with a 'stem'; drill
hammer site to accept moderate press-fit for
stem/shank, and use permanent threadlocker.

Maybe?

 

[Hugger-4641]

Where does one get little bits of steel?

Google 1084 or 1095 and thickness you want and you'll come up with lots of sources. Here's one for 3/16":
https://www.etsy.com/listing/683778...EYWINnCe6H5-ofa0KAGXH6OoS6MgT5HhoCxLcQAvD_BwE

 

[BBBBill]

@Johnm1
A few metal suppliers to choose from -
OnlineMetals.com® | Buy Metal Online | No Minimums or Cut Fees!
Metals Depot® - Buy Metal Online! Steel, Aluminum, Stainless, Brass
Speedy Metals Online Industrial Metal Supply
Hobby Metal Kits LLC

 

[dfariswheel]

Brownell's sell steel for gunsmiths.............

https://www.brownells.com/tools-cle...-tools/shop-supplies/extra-wide-spring-steel/

 

[jdsingleshot]

Seems to me that in silver soldering anything that close to the sear, you are bound to reduce the hardness of the sear. Why can't you just Dremel a notch for the half cock position?

 

[WestKentucky]

Is this for the S&W 44?

I totally misunderstood what the plan was. Seems you could just cut the notch deeper on the hammer, but that’s just my take on it.

 

[Big Bore 44]

Go to the local scrapyard and get an old car spring. A Chevy leaf spring will be enough good steel to fix many of those hammers.

 

[Jackrabbit1957]

You could try a piece of hacksaw blade, plenty hard for what you're doing. It will also bend to a certain extent before breaking and it may be thin enough as well. Another source is to check with a small engine repair shop and see if they have an old spring from a rewind starter off a chainsaw or a lawnmower laying around. I used to have one myself, made a few parts from it, let me look around and see if I can find it.

 

[Johnm1]

Why can't you just Dremel a notch for the half cock position?

Seems you could just cut the notch deeper on the hammer,

I wanted to just cut a deeper notch. Beginning at post 23 on page 2 of the below referenced thread I eliminated that option based on how the rear sear would collide with the trigger guard.

https://www.thehighroad.org/index.p...eah-this-is-getting-old.919057/#post-12655130

Difficult to explain but cutting the notch without adding material changes how the rear sear interacts with the hammer. It requires the rear sear to travel uphill instead of downhill on its way to the end of the double action pull. One of my attempts at adding material and cutting a new notch cut the notch too deep, similar to how it would be cut without adding material. Because of the uphill travel, the double action trigger pull was almost unusable.

 

[jmorris]

I'm researching the feasability of shaping a part to replace a half cock notch on a hammer and attaching it mechanically and silver soldering it in place when fitted.

I would probably just TIG using 4130/4140 filler rod and make it the shape you are wanting.

I have successfully repaired bolt cutter heads with this method and you can be precise in your application of heat to the part too. Like welding to this little broken drill to remove it from the part it broke off in.



Build the area up with filler and reshape.

 

[Varminterror]

The proper task would be to fill weld with a hardenable fill, then heat treat once reprofiled.

This silversoldered piece will break free with use. Not the right technique for the task.

 

[Johnm1]

The proper task would be to fill weld with a hardenable fill, then heat treat once reprofiled.

This silversoldered piece will break free with use. Not the right technique for the task.

As a rank amateur, I do appreciate the information. Accepting this is the wrong technique for the task, does it matter that the added piece is mechanically attached with a screw as well? Could it hold if both screwed and soldered?

The reason I chose this method over welding/shaping again, aside from the fact I tried that 3 times and failed*, was adding material and shaping only address' the missing half cock notch. It doesn't help the push off the revolver also suffers from. My thought was if I could extend a piece to the full cock notch I might be able to add a little surface for the rear sear to rest against and cure the push off. Surprisingly it does work. It looks like hammered dog poop, but it can't be pushed off. I thought I was going to have a double release of the sear, but surprisingly I don't. It functions as it should. At this point the added piece is only screwed in place and this can all be 'Undone'



*While making this part I did learn why my previous attempts to add and shape failed. One must strategically remove excess weld material when first fitting the hammer into the frame. With what I know now, I could weld and shape now. But I'd still have the push off issue.

FYI - the full cock notch is only 0.020" tall with a slightly acute angle. Here is a picture of a similar hammer from a 38 caliber revolver showing a normal/functional full cock notch.


The notch I'm working with looks very much the same. It isn't obviously worn out of shape except for a couple of scratches. It holds but pushes off with very little force. So it's worn. I don't know what tool could be used to recut a notch that small. Certainly nothing I own or have the knowledge to use. Jackrabbit has a tool/jig for cutting notches but I couldn't envision how it could be used to cut something this small and shape.

 

[Johnm1]

I would probably just TIG using 4130/4140 filler rod and make it the shape you are wanting.

I so much wish I could weld.

 

[Hugger-4641]

German machinist apprentices are given a block of steel and a file to make machine parts from.
You can probably order some needle files small enough to make that notch.

 

[Varminterror]

I so much wish I could weld.

Small projects like this can often be knocked out on a slow Thursday afternoon at any fab/weld shop, I’ve had a lot of work like that done for $20 or a few cold beverages. I can weld, but I’m not good enough to weld small parts, let alone stainless, so that’s my solution when these projects present themselves.

 

[doubleh]

I made my living for years as a ASME Code 9-G 6 certified welder. Tiny to huge and 25 to 5,000 # operating systems, both gas and water. Now if I had to choose between making a weld or getting shot I would just have to say to go ahead and shoot me. Essential tremors have taken that skill away from me. 30 years ago I would have quickly done that little job but no more. A tig rig would make quick work of it. I loved to weld stainless pipe but all we used was 316, one of the true stainless steels so no experience with other classes.

 

[jmorris]

I’ve had a lot of work like that done for $20 or a few cold beverages.

He’s not kidding, I’ve done a lot of little things like that in trade of cold beer, over the years…

 

[a5werkes]

aside from the fact I tried that 3 times and failed*,

Thomas Edison famously said, "I have not failed. I've just found 10,000 ways that won't work!"

Kudos, keep after it.
https://goleansixsigma.com/not-failed-ive-just-found-10000-ways-wont-work-thomas-edison/

 

[Johnm1]

Thomas Edison famously said, "I have not failed. I've just found 10,000 ways that won't work!"

Kudos, keep after it.

So far I've found a lot of ways not to do it.

I was pretty surprised that the added piece does cure the push off. And it wasn't that difficult to fabricate. I used an old S&W mainspring as the stock. It had a slight curve that I needed. I thought fabricating a piece to form a half cock notch would be easier. But not so.

The surface of the hammer that was removed by the previous owner (half cock notch) and I’m trying to replace determines both the angle and travel of the rear sear into the half cock notch. Too much height and the double action sear can’t reset. Too little height and there isn’t enough space for the rear sear to move into the notch and hold. If the thickness/angle of the added piece is wrong it presses on the sear and prevents it from rotating into the notch.

It takes a couple hours to whittle a 1/4” x 1/4” piece out of hardened material. It takes minutes to do the same out of brass/copper. So for testing I tried making parts out of copper. But those pieces only last a couple of cycles in the gun while testing and fitting. Overall the right answer is a new hammer. Short of that I think welding material and shaping just the half cock notch is the way to go.

I can't solve the push off with added weld material unless I find the tool to recut it. So for now the added piece for the push off is going to stay.

Oh, and if the full cock notch is cut a billionth of an inch closer to the front of the revolver one can set the single cock by using the double action trigger pull. Even though this action is different than modern double action revolvers, I suspect that is true for modern revolvers.

 

[Johnm1]

Build the area up with filler and reshape.

But how do I find someone who can weld like this?

I've tried taking a small part to a random shop to have a small amount of material added and it was expensive and not very useful. Way too much material. Do you figure my local gunsmith is the right person to do some TIG welding on a small piece?

 

[jmorris]

But how do I find someone who can weld like this?

Mail it to me with return postage and post a copy of your first photo of exactly where you want it built up and by how much in thousandths of an inch. Like this.