The M5906 Project

[Old_Cop]

Pay attention, this is how a professional works.

 

[vigil617]

This has to be the best post that I have ever read on any gun forum, ever.

The pictures, the procedure , and the information.

Great post.

Mike, you ain't seen nothin' yet!

Look up some of BMCM's other threads about different repair and customizing projects and you will find similarly amazing, detailed, and well-written descriptions -- all with Bill's flair for humor -- that will capture your attention for hours. This man is the real deal.

Bill, one observation on this part of the M5906 project: who'd a thought that the grip screws would be metric?

Is it your experience in other S&W projects that metric, as opposed to National Coarse ("standard") or National Fine ("SAE"), threads are often used? As an American manufacturer with plants here in the States, S&W puzzles me by this choice. I know gunsmiths must use a lot of very small, fine threads, so maybe there are comparable American thread systems besides the ones I've mentioned, but as for metric, I'm surprised, that's all.

 

[BMCM]

Bill, one observation on this part of the M5906 project: who'd a thought that the grip screws would be metric?

Is it your experience in other S&W projects that metric, as opposed to National Coarse ("standard") or National Fine ("SAE"), threads are often used? As an American manufacturer with plants here in the States, S&W puzzles me by this choice. I know gunsmiths must use a lot of very small, fine threads, so maybe there are comparable American thread systems besides the ones I've mentioned, but as for metric, I'm surprised, that's all.

Well, these grips are crafted in Germany by the Karl Nill, Nills-Griffe Company. I gather Metric is a thing over there on that side of the pond. Were you to check any of the top shelf PC guns that were originally equipped with Nills wood grips, I'd wager every one of them are fastened with the very same M4 screws that Nills supplied to S&W with the grips.

I don't really have issues with Metric per se. What really gives me heartburn is when I'm working on some machinery or vehicle and I find a mishmash of fastener standards. I've come across this a number of times on vehicles ans it's really REALLY annoying. Imagine, for example, all the fasteners on the accessory belt driven junk is Imperial and where all the brackets are fastened to the engine and all the engine bolts are Metric. So I need two complete sets of tools to repair the cursed thing Makes me want to go visit the company CEO that made that piece of junk and punch him right square in the face

Cheers
Bill

 

[vigil617]

Well, these grips are crafted in Germany by the Karl Nill, Nills-Griffe Company. I gather Metric is a thing over there on that side of the pond. Were you to check any of the top shelf PC guns that were originally equipped with Nills wood grips, I'd wager every one of them are fastened with the very same M4 screws that Nills supplied to S&W with the grips.

I don't really have issues with Metric per se. What really gives me heartburn is when I'm working on some machinery or vehicle and I find a mishmash of fastener standards. I've come across this a number of times on vehicles ans it's really REALLY annoying. Imagine, for example, all the fasteners on the accessory belt driven junk is Imperial and where all the brackets are fastened to the engine and all the engine bolts are Metric. So I need two complete sets of tools to repair the cursed thing Makes me want to go visit the company CEO that made that piece of junk and punch him right square in the face

Cheers
Bill

<smh> Of course. The screws that came with the Nills grips are metric, and those screws are what you used to secure the grips on your fixture. Perfectly sensible.

Now, though, for the ultimate attachment of the grips to the frame, aren't you faced with the choice of either using the Nills screws and having to re-tap the 5906 frame (filling the old holes with weld first), or using the old 5906 grip screws with the new grips to avoid the re-tapping? Do the holes even match up to begin with?

 

[BMCM]

Ahh but you are assuming the 5906 has holes drilled to begin with. Plain Jane no frills 5906 is not drilled & tapped so I'm more 'r less at liberty to use anything that strikes my fancy. The limiting factors are 1) the diameter & depth of the counterbore housing the screw head in the wood and 2) the combines thickness of material the screw must fit through and 3) the thickness of the steel on the sides of the magwell through which we drill & tap and the shank of the screw must hold fast.

In this case the head of the supplied M4 screws and the counterbore in the grip is precisely 8mm in diameter. The screw heads are also relatively thin being a tad over 2mm thick and the threaded shank is only 4mm long. I have ID'd a 316L stainess screw that's close but with a 6mm long shank that I'd need to trim.

I have not been able to find any Imperial screws that have a 8mm diameter head that will precisely fit the wood. Then again I haven't really looked that hard for SAE screws. What I'd really like to find is a set of screw in titanium either slotted or torx that I can flame anodize

As it stands currently I'm not seeing any reason to reinvent the wheel, I'll roll with the screws supplied. Plus i already have to tooling to drill and tap the frame for M4 x 0.70mm

Cheers
Bill

 

[Pine_Worker]

This guy is amazing!

 

[BMCM]

Happy Independence Day Gents,

Got a little bit done on this project today sitting around the homestead doing by social distancing bit. If truth be told, I was social distancing long before there was a pandemic

Anyway, lets get to work shall we?

So, what I need to be able to do here is hold this grip panel by the area under my thumb pretty rigidly in order to perform a couple machine ops on the opposite end...

We're going to use another piece of that half by one inch tooling plate about 6 inches long to make another fixture to hold these grips. First order of business, we need to take a few measurements...

We'll need to know the height of that raised boss in the middle and the radius of those curved edges on that boss...

And, we need the width of that groove between the spine and the boss here...

5/16" radius gauge tells me a 5/8" diameter cutter will match that curve. I don't have one but as long as I go a touch smaller we'll be fine. I'll use a 1/2" cutter.

That gap measure a bit over 3/16"

We already know the angle on the boss is 74° from the previous installment so my vernier protractor is so set and I have the caliper locked down at 0.195"...

Splash some layout dye on our piece of tooling plate and using those tools, scribe the area the needs milling out onto the stock...

Now over on the mill, we have our marked stock propped up on a couple parallels in the vise and aligned parallel to the Y axis. Cutting 0.080" deep with a 1/2" 3 flute carbide end mill turning at around 900RPM...

Then we swing the vise over to 74° and lock it down to for the cleanup cut on the angle...

So far so good...

Clean it up and back to the bench to check the fit, Good to go...

Now we flip it over and take our M4 transfer punch and mark the fixture for a drill & tap operation...

Drilled the fixture with a #30 bit then tapped metric M4-.7 pitch
Grip fits on there nice and secure with a single screw snugged up...

Now we repeat all those steps again on the opposing end and side of the fixture so I can hold the other panel in the same fashion...

With that done, we will next turn our attention to the frame...

A little layout dye...

Set the grip in place making sure it's snugged up tight at the top then mark for drilling with our M4 transfer punch...

Once we have both sides, all four holes, marked... Frame gets strapped down on the mill table for drilling & tapping. Here we're spotting the first hole with a small center drill...

Swap bits to a #30 cobalt drill and poke the hole clean through...

Starboard side done. Flipped over and re-secured to tackle the port side...

I power tapped all four holes right on the mill but neglected to capture any pics of that. Just chucked the tap and with the spindle running at about 170RPM just lowered the quill and let the machine do the work. Turned out just fine, Looks like I got the holes located where they ought to be...

Now we get ready to put that new fixture to work. First fasten securely the port side panel...

Then flip 'er over and take a pencil to outline the area below the boss where the frame window is unfilled...

Like so...

Swap panels and repeat that step with the starboard side panel...

Now with both panels marked we're gonna take that little tiny dovetail cutter and head over to the mill with our new fixture to make some adjustments...

Here's the setup. Starboard panel on the fixture, clamped in the vise, vise swung to 74° left and locked...

What we're going to do here is take that tiny dovetail cutter and make a beveled undercut on the bottom edge of that raised boss along here...

Then traverse the Y axis a bit and make a plunge cut in the center of that marked area to create a dovetail slot about 0.050" deep right about there...

There's our little undercut done...

And there's the slot...

Then we repeat those steps. With the port side fasten to the other end/side of the fixture then clamped in the vise which is now rotated to 74° right...

When we're all done we have opposing sides each with a matching small undercut and dovetail slot...

The point of all that is to provide and mechanical anchorage for some filler compound I'm going to use to enlarge the boss to fit the frame window which we're going to cast in place on the frame.

We'll be playing with that stuff in a day or two, stay tuned.

Cheers
Bill

 

[vigil617]

Bill, I gotta say, using that little dovetail cutter instead of a straight end mill is genius. Genius, I say! The joints that you will achieve with your filler compound will be so much stronger and stable that way. That's some head you got on you!

Happy Fourth of July, Master Chief!

 

[Tom Kent]

You have more talent in two seconds than I have had in 74 years. My hat is off to you!

 

[Green Frog]

Bill, I’m enjoying this series of your posts way beyond measure. You have graphically demonstrated the two classes of people who work on guns, the “Parts Changers” like myself who simply take existing parts and try to put them together in a way that will work, and the “True Gunsmiths” who make, modify and fit parts in such a way as to perfect the vision of a particular gun. Thank you for the inspiration.

Froggie

 

[KWIndy]

How is this project going BMCM?
Any updates?

 

[DMcBB]

Hey Bill, any news? We’re all waiting with baited breath to see how this 5906 turns out!

 

[BMCM]

Well, the thing is I have folks paying me to fix up or mod their guns of which I have several on the bench right now. I just don't feel it's right for me to be mucking about with my personal stuff when folks are paying me to work on their stuff. I think I'll be picking this 5906 project back up soon after the holidays however, stay tuned.

Cheers
Bill

 

[DMcBB]

Bill! Any movement on this project? It’s just too cool to leave alone!