.38/.357 prototype

[bruski]

.Cutter,

 Your pan turned out nice. Did you post it from the cad model drawing that you sent us?

bruski  

[Cutter]

.Cutter,

 Your pan turned out nice. Did you post it from the cad model drawing that you sent us?

bruski  

Thanks bruski

 

Yes , same model.

It will work for either 3/4 or 7/8 bolts.

It’s shown with the 7/8 bolt carrier.

[Sparky_NY]

 

Setup, a simple program, push the button, take a nap.

I’ll be back in and hour.

 

(Geezer schedule) 

 

Do you drill holes for bolts first then profile around the OD, or just profile everything from the round blank?

[Cutter]

Do you drill holes for bolts first then profile around the OD, or just profile everything from the round blank?

 

Profiled the flats and radius, the OD

was finished on the lathe

I used a 3/8 extended 2 flute to reach 2.250

[Sparky_NY]

 

Profiled the flats and radius, the OD

was finished on the lathe

I used a 3/8 extended 2 flute to reach 2.250

 

Thanks, great info.     I will do mine that way too,  previous ones I drilled the bores then profiled,  your way is easier.

[bruski]

How do you profile the flats on a lathe that is meant for turning a radius?

bruski

[bruski]

Never mind, I misunderstood the post. I started to think that I wasn\'t using the lathe to it\'s full potential for a minute there.

bruski

[Cutter]

Guys,

Take a look and lets hear what you think

 

The white is the bolt with a .312 hole through, I can drill

it from both ends. The red is a bushing for the firing pin,

it has a .0625 hole through. The red is pressed into the bolt end up to a small shoulder.

The green is the firing pin going through the red bushing and threaded through the yellow one.

The firing pin will also slide through the purple bushing. The purple bushing is a threaded

insert in the end of bolt. The threaded yellow bushing allows adjustment for the firing pin length

with a positive stop.

Thanks Jerry

[Sparky_NY]

Very similar to what I came up with except no red bushing,  I plan to drill the 1/16 from the face end of the bolt.

[Cutter]

Just because everyone likes videos and sometimes they inspire

 

 

https://www.youtube.com/watch?v=9WbRpjlacwQ

[Cutter]

Some gear-head info

[bruski]

I don\'t think the .312 through hole is necessary for me any way, maybe for your longer bolts though. The video is nice to watch while it reminds us of our goal it also has the excitement with it to give us a kick in the pants to keep working on ours. Thanks.

 

 In the pictures you will notice 6 bolts fitted to the carrier at last. I had to pull a lever 6 times to get them which took quite a bit more effort than cutters push button machine,lol. The holes are not drilled yet for the firing pins though, more on that later.

bruski

[Sparky_NY]

Guess I am attacking from the the rear.   I did some test drilling for the bolts today,  5/16 for 3.7 deep followed by .1935 for another 1.8 depth,  have to drill the 1/16 hole about .75 deep from the other end of the bolt but that should be easy.     My concerns about that deep drilling in 4140 prehard are no longer.   Peck drilling on the cnc lathe is the hot ticket.   Only did one as a test.   Will make up a test firing pin assembly shortly.

[Cutter]

I don\'t think the .312 through hole is necessary for me any way, maybe for your longer bolts though. The video is nice to watch while it reminds us of our goal it also has the excitement with it to give us a kick in the pants to keep working on ours. Thanks.

 

 In the pictures you will notice 6 bolts fitted to the carrier at last. I had to pull a lever 6 times to get them which took quite a bit more effort than cutters push button machine,lol. The holes are not drilled yet for the firing pins though, more on that later.

bruski

 

 

bruski,

Before I got my CNC I made my first RG-G cam that way.

Stepping off every degree, except the straight cut

[Cutter]

The 7/8 bolts are drilled through , 5/16 diameter.

Next, counter bore both ends for bushings, rear one threaded.

After that, mill flats and a hole for the pressed in follower

[Sparky_NY]

TO quote my hero   \"Setup, a simple program, push the button, take a nap.\"

 

Material: Bearing bronze,  16 pitch, 12 tooth, left hand, 45 degree, 1/2 bore, cut with a .093 flat endmill   Camera makes the finish look a lot worse than it actually is.

 

  I will make the 24 tooth next to complete the 2:1 drive gears, probably from steel.  

 

 

 

[bruski]

Sparky,

 That gear turned out really nice with an end mill. You pushed the right buttons on that for sure.

 

 I drilled one of my bolts today and spent some time re-designing the firing pin in my head but then I was interrupted with some honey do\'s.

bruski

[Cutter]

Great job Spark, very impressive 

[Sparky_NY]

 

Great job Spark, very impressive 

 

Take a look,  gearotic motion.     The trial version is full featured except you can\'t save the file.    Art, the guy who wrote Mach3 is the author of this software, he gave me a copy years ago and I just now got to try it out.

 

http://gear2motion.com/\'>http://gear2motion.com/

[bruski]

Well, I got a little bit of time in on the first completed firing pin re-worked from the Enfield pin on the bottom of the picture. It would be better off just to turn them from drill rod because of the uneven hardness in the Enfield pins. I will pin the increased in size (.350 OD X .370 L) bushing in the rear of the bolt with a 1/16 diameter roll pin. The sear knob on the tail end will be silver soldered or welded to the firing pin. So there won\'t be any spring changes possible with this one. I will probably thread the sear tip on the others with about a 10-32 thread and loctite them on.

bruski