K32 build....

[shovelwrench]

Hondo, Thank You!!

I understand peening the ratchet, and fixed ONE revolver doing that!! (940)

In this case.. The ratchet itself is like new, as is the entire cylinder eBay nearly gave me

While this is an inexpensive adventure(relatively), my last .32 build was the test subject, this one I want near perfect. I'd rather have something timed a little advanced, and work my way back.

After seeing the wear spot on the current hand, I think a replacement and re-fit are in order?? (throw me your opinions)

Its .095" wide..

I absolutely want to here your guys thoughts!!

While I understand how everything works together, by no means do I have the experience..... I can take measurements, and make chips. HOPEFULLY the tolerance stacking gods are kind to me!!! LOL


On a side note.... I have to punch the hole for the pin that will retain my locking bolt, and locking bolt "housing". Then finish the muzzle/crown and the barrel is done except for attaching a front sight and addressing the sight rib/flat/grooves(terminology??)!!

 

[Jebus35745]

I have addressed a slow timing on one cyl hole a few times like Jim suggests. Works great. I mark the ratchet tooth needing attention with a magic marker so it is easy to find after you close the cyl to see if you fixed the problem. I envy the heck out of you being able to do this yourself. Jim is handy at customizing S&W's also. I look forward to seeing the progress on your gun, very interesting. Larry

 

[Big Cholla]

SW: Your 'hand' looks perfectly normal to me for a handgun of that age and use. And, 0.095" is a normal hand average. Your 'best' fix is to just use the very clear and well written directions you received from Hondo44 and peen the offending extractor star boss just ever so slightly. That will take care of the problem.

Substituting a wider hand very well could cause timing problems with one or more of the other chambers. .....

BTW: My complements, you look to be an above average ability (and results) machinist. That is a skill I don't take lightly. .....

 

[Hondo44]

Then finish the muzzle/crown and the barrel is done except for attaching a front sight and addressing the sight rib/flat/grooves(terminology??)!!


Congrats on the barrel; beautiful machining!

Most refer to those grooves in the rib as striations or serrations. No doubt the factory has a specialized milling cutter to do them. Likely an expensive custom cutter and not worth the cost for a one time job.

I have never cut new striations except on front sight bases and other small parts. But I have cleaned them up for a re-blue with a 40 LPI checkering file.

On the cyl hand, the old timers would "stretch" a worn hand.
With a guide clamped to the work to keep the file straight, the checkering tool might do a fine job.

 

[Protocall_Design]

Great build you have going Shovelwrench!
Revolver smithing is the art of adjusting that which is non adjustable. For the hand, a quick, easy way to advance the timing is to bend the hand a few thousandths to the left, or towards the center pin. The hand is too hard to bend, but the pivot pin will bend. This works best on a gun with all the ratchets worn down the same amount.

What happens is, when the hand is raised by the trigger, it is leaning in as far as the frame will let it. When it turns the ratchet to the stopping point it goes to the right, around the ratchet and up to the end. In some cases, it may be necessary to file the hand window inwards a little to allow the hand to move over some more. This is more of a field fix to get by until you can get an oversize hand and do it right.

For the grooves in the top, you can lay the barrel in a T slot on the mill table with the top facing horizontally, tie it down with a strap clamp or 2 and use one of the cutting tools mentioned above. The T slot will accurately align the barrel with the X axis of the mill.

 

[shovelwrench]

Thank You everyone for the advise, kind words, and support!!!!

Spent some of the day in the shop today and yesterday.

I set everything up to drill the hole for the locking bolt Friday night, but had to run into my friends shop for the .043 carbide bit I purchased to use on my last .32s replacement hand (that's a whole nother story, I frame, broken hand)...

Anyway, drilled that hole.... Long story short, hind sight being what it is, should've put a plug in the locking bolt housing and gone all the way through. Wound up with the hole .020 off on the other side.

So today was spent making pins to fill that hole, then re-drilling it all the way through from the other side....

I'll have to open the recess up in the barrel where I relieved for the holes to make it look "right", but all and all, turned out well!!

This is the good side, once I touch things up I'll throw up pics of both sides.

 

[shovelwrench]

OH!!

My cylinder gap is a hair tight too..

.002, Problem??? Figure I can always open that up later if need be...

I'm also likely to make a new extractor rod, this one is tweeked a hair and slows a couple more chambers down. I was never really happy with how the threads looked either!!

They're 36tpi, correct!?!?! (this one is right hand)

 

[Protocall_Design]

You probably want around .003 minimum if you only shoot jacketed bullets. If you shoot lead or a combination, .005 to .006 is the minimum.

 

[shovelwrench]

SOOOOO,

Apparently the proper slot cutter for the rear sight stud is made from unobtanium!!!

Took me while but I found one and its on the way!!

I'm going to pull another revolver apart and copy the rear sight cut dimensions.

I also set up a grinder in the horizontal mill vise and modified an .045 slitting blade to cut the barrel serrations. I'm going to play around with some scrap before I commit to using this method, but the small amount of testing I did do look promising.

I'm thinking next step is going to be machining for the rear sight and making a front sight. Since I'm thinking of running the barrel serrations part way into/up the sight ramp.

So with a .160 rear sight, does anyone know the approximate front sight height???

Would middle of adjustment on the rear, then measuring height off the bore, and matching the front to that get me in the ballpark?

I'm probably going to make the front tall, then before bluing and final teardown, do some test shooting with the file handy...

I took next week off, so hopefully will have some more progress on this by the new year!!!

 

[Protocall_Design]

Your sight measuring plan should work fine. You may want to make the front a bit taller than the numbers, just to be sure you have enough.

 

[drgbike]

If you can say, where did you get the t slot cutter. Great story line thanks.

 

[shovelwrench]

If you can say, where did you get the t slot cutter. Great story line thanks.

I actually found a few available different places. Hard part was finding a distributer that I didn't need a corporate account and could web order...

Here is the one I got....

Here's the product listing from the manufacturers page

There's also one from MicroCutusa.com available through MSC, but their quote was 109$ before shipping was added.....

 

[steelslaver]

What I use cutting the slots for the rear sight nut is a small HSS 2 flute end mill that I modified with a cutting disk on a dremel tool. I believe it is a 3/16 end mill and I just removed the flutes above the thickness of the nuts flange leaving 2 teeth on the end of the mill. Then I cut the slot the right depth with a regular end mill and follow up with the modified mill only doing the under cut. Works well for me. I have 2 of them out in the shop and it you want could get one and try to take a decent picture of one.

I got tired of searching for the correct cutter online. But, am saving your link thanks.

 

[steelslaver]

PS, I like what you have done with the barrel and how you are doing the rod latch set up. Looks like your going to end up with a very nice 32.

 

[shovelwrench]

Again, thank you everyone!!!

So I did get quite a bit done.

I finished the muzzle. And since I did, I couldn't use the giant pliers I had been using to take the barrel on and off. So at that point I also needed barrel blocks.

Made a front sight from the peice of barrel that was also used for the locking bolt housing.

I soldered the front sight on and went to setting the barreled frame up for machining. I used a cutter from the horizontal mill to shape the sight radius. Then used another, identical cutter, that I ground to 60 degrees to cut my striations.

This is the sight after the initial radius cut.

And cutting striations.

I also stepped the front sight. The sight is REALLY tall yet until I get the rear on and get height reference and some rounds through...

Also, I'm at 80 lines per inch on the striations. Let's just say, the plan was 40!! Had a friend stop and distract me in the middle of a knee adjustment... And then it was 80. I'm going to machine the rear sight to match the 80.

If you see there's some minor cutting on the top strap in the front. That is gonna clean up when I machine for the rear sight.

Next is rear sight, and the cylinder!!!!

 

[Nighthawk0083]

I cant wait until the next episode!

 

[Krogen]

I'm really enjoying this thread. I wish I had the skill and equipment to do exactly the kind of things you're accomplishing. I'll just settle for watching it happen. Thanks for sharing your journey!

 

[steelslaver]

Nice recovery from you groove problem. Things happen especially in one offs. Think its going to look great when your done.

 

[armorer951]

Great thread and photos, thanks. Was there a reason why you decided to fabricate/use a traditional front locking bolt, instead of installing a detent in the yoke?

 

[shovelwrench]

Nice recovery from you groove problem. Things happen especially in one offs. Think its going to look great when your done.

Thanks!! DEFINITELY learning a lot!!

Great thread and photos, thanks. Was there a reason why you decided to fabricate/use a traditional front locking bolt, instead of installing a detent in the yoke?

I never really cared for the aesthetics of a revolver with a barrel that didn't hide the extractor rod inside its radius without a locking bolt. And the challenge/lesson.

I very well might add the detents before I decide I'm done though....

 

[Troystat]

Really neat project. Can't wait to see the end results and to hear how it shoots.

 

[badwhale]

subscribed

 

[shovelwrench]

Got to do a little more last night.....

Its funny how the external dimensions on these revolver are fairly destroyed by the polishing/finishing. It took me quite a while messing around weeknights to figure out where to indicate from before I could start machining.

What worked best was sticking a VERY snug gauge block into the rear sight notch. As this is one of the few square and unfinished machined spots left.

Indicated in to well under .0005 and verified by measuring barrel runout, I could finally start machining for the rear sight.

I took this one just to show the cutter, it always amazes me how well a cutter this small , made from solid carbide, removes metal!!

After this pic I test fit the sight and wound up cutting the rest of the U-cut, where the old sight notch resided, forward till its just about gone. Then moved the rest of the dimensions forward to match.

You can see the U-notch clearly here, but its only a few .001"s deep at this point, really its just enough left that the bluing remained.

Also, you can see where the firing pin has been eroding the frame!!! While I'm going to move that whole radius forward a little and wind up having more meat there, should this have the spring in the hammer nose??

 

[shovelwrench]

Today I'm going to drill for the sight screw, and attach a digital scale to my quill before I set up to ream the cylinder....

AND, pull the sideplate and clean internals...

 

[Hondo44]

Neat work!

You might consider the longer version rear sight with serrated tang that meets the barrel rib serrations, so you don't have the blank spot between the front end of the rear sight and the back end of the rib.

Although you may want the blank spot since the serrations of rib and sight tang are different lines per inch.

 

[shovelwrench]

So I indicate the rear of the cylinder in to dead on with a .0005 coaxial indicator.

Then I go for a chamber.

The chambers aren't quite straight, from the rear to about midway they're off by .001x .002y. I didn't get a chance to put a feeler on long enough to reach the forward end of the forcing cone yet.

BUT, my question...

Should I be indicating from the rear of the chamber, Or center it up on the forcing barrel end of the cylinder??

OR, am I putting way too much thought into this!?!?!

 

[shovelwrench]

Hondo44,

That's a very good possibility, Is the screw location the same on the "old" style sight??

I am going to see if I can add the extra lines in the current sight!!

 

[teletech]

Sorry I'm too late to help you, but perhaps it will be of value to others:
I've had good luck using a threadmill for work like that, but considering what some of those cost I've been known to grind a tap so it's one-flute and use that to get a matching set of v profiled lines.

Does anyone know how S&W cuts the grooves down the center/top of the barrel. The fine, threadlike finish that continues on the rear sight??

 

[shovelwrench]

That is something I hadn't considered....

I'll probably try that out on something though, thank you.

 

[Protocall_Design]

Hi Shovelwrench -

The mounting holes on the rear sights are all the same for the newer round end style. The holes on the square end ones are all over the place, depending on what model they are for.

In the picture of the mill setup, here's what I would do.
Tram the head of the mill to the table (or the vise bed) so you know it is perfectly square (or as close as you can get).

Put the 2 clamp bars on parallels in the vise without the cylinder, the same way as they are in the picture. Rebore the hole for the cylinder. Mill .010 off the inside of each bar so they will clamp on the cyl. With the bars sitting on the parallels, put the cylinder back in the clamp. It will now be exactly perpendicular to the vise and the holes will be straight. This pair of clamp bars will fit all K frame cylinders.

When you dial in an outside circle with the CoAx indicator, you want the curved feeler to be on the other side of the part from the way it is shown, going around the outside circumference. For a hole, you will use a straight feeler. I have found the CoAx indicators are not as accurate as a dial test indicator or a good edge finder. I have a Blake (good one) and it's that way too.

With the cylinder in the clamp blocks and the front facing up, locate the center of the first hole with an edge finder. The .22 hole is small, so use the pointed end about .1 down in the hole. Run it at around 1000 to 1200 RPM and touch off one side of Y axis, zero the setting, touch off the other side and get a reading. Divide that number by 2 to find center. Do the same for X. This will get you exactly on center without the worry of whether the cylinder is indexed exactly along the X or Y axis. Do this for each hole. I don't know if you have a DRO or not. It's really a time saver. Otherwise make sure you compensate for slack in the leadscrew. Lock the X and Y so the table doesn't move during the cutting process.

Drill the hole through with a 19/64 drill, then ream with a .312 reamer.
Once all the holes are reamed through, you can turn the cylinder over and run the chamber reamer from the back side. The chamber reamer pilot will run in the .312 reamed holes.

This is probably more information than you actually needed, but I hope you find some of it helpful.

Best Regards.