[bumthum]

Okay, I thought it was about time to get this thread going as I have made some real progress and actually have something to write about. I realize that this is a Saturday Night Special topic, but it is a form of literal gun smithing, so I thought this would be the most appropriate forum to have this discussion in.

Just some background on me, I have an associates and a bachelors degree in Mechanical Engineering Tech from Purdue, but I am not a professional engineer, a full fledged ME, I'm not in the firearms field, and my ideas and advice are mine alone. If you attempt to do anything like this DO NOT copy my processes and procedures unless you do thorough research and decide mine are best practices. I'm not going to include dimensions, etc, because I'm not sure what the limits are for that information (I know 1A versus ITAR and whatnot), I like these forums and do not want them running afoul of any changes in political winds from the glowies. End of disclaimer...

Evolution of my 3D Printed Raven frame as of 15 Apr 22:

So in school we used Solid Edge / Solid Works and I'll admit that I really grew to love those programs, they're both are pretty powerful in my opinion. I've had to relearn some things to use Fusion 360, because I'm to frugal to fork over enough scratch for those other programs. I needed a test bed to get the hang of Fusion, getting things sliced in Cura, and then printed on my Ender 3. It's ugly and basic, but I sorted out what I needed to do.

Next I sat down with a pair of dial calipers took dimensions directly from a P-25, jammed them into a sketch and did some basic extrusions and cuts. I was mainly looking to sort out the pockets for the Retainer (Part# 100-9) and the Sear Assembly (Part#100-10). The first frame lacked a trigger guard and is pictured below.

The next iteration included a trigger guard and recesses for the grip panels as well as screw holes to secure the grips. It was this frame that I first revealed in the SNS Safeties thread and shown below. Note that there is no inletting for the Trigger (part# 100-17), its associated parts (part#s 100-22, 100-23-5, and 100-23-9) or fire control mechanism all inclusive. The first two Raven frames were early iterations and I never got far enough on them to include those features.

At this point in the story life intervened and I had a pile of personnal and professional issues to deal with that stopped work on my hobbies (I even briefly considered getting out of my guns completely to raise needed cash). Time passed and life settled down a bit, so I got back to work. I decided to start all over again from scratch, some of the dimensions on my previous frame were off by a noticeable measure and I had gotten the wrong angle on the magwell so it was impossible to get a magazine in and out smoothly.

I sat down with my calipers and an MP-25 this time and began grabbing dimensions. From that I created a new sketch and, fortunately, I located my angle finder and was able to properly design the magwell this time. The results are below, while both are slotted for the trigger and include pockets for the retainer and sear assembly, only one has the inletting and recesses for the fire control components. It was this frame that I included in a later SNS Safeties post and it turns out that the fire control parts interfaced perfectly. The only change I needed to make was a sloppy pocket for the sear assembly.

Next there was a flurry of activity, slightly moving pin holes, rounding the edges, trying to sort out the pocket and pin hole for the Magazine Catch (part# 100-15) and the Catch Spring (part# 100-23-4). Note: Spoiler alert, I'm still trouble shooting the pocket for the magazine catch and spring. As you can see below, these three frames are broadly similar with the only difference in the first two being the location of pin holes and the third frame including recesses for the Grips (part# 100-14) and holes for the Grip Screws (part# 100-24). These frames are slightly shorter in height than the darker red frames as I discovered that the magazine was unable to protrude far enough into the frame when compared against a real MP-25.

My most recent iteration, as of 15 Apr 22, is the white frame below. Basic tweaks were made to the magazine catch pocket and the angle set into the recesses for the grips to make them parallel with the bottom edge of the Slide (part# 100-3). The frame is once again a bit shorter to better accomodate the magazine length and, as I knew the locations of the pin holes were correct, I never bothered assembling the fire control parts onto it to test for fit. I know it's difficult to see the frame in the photo below, but trust me... it's there.

That sort of give an idea of frame evolution to this point. I must say, I love that CAD/CAM and 3D printing enable rapid design iteration. So far this has been more time intensive than actually stressful, although I still need to work out the magazine catch pocket. Once I have all of the frame centric details sorted out, I'll start dealing with how I'm going to mount a parts kit barrel, that will involve more changes to the frame, but I want to get the basic details done first.

Next post I'll cover some basics about the frame design itself. I have some down time coming up, so hopefully I'll get the final basic elements of the frame done within a week or so and can do another post on frame evolution. If you're interested in this thread, let me know. If you're not interested, let me know. If it needs moderated or pulled, that's cool too.

 

[moona11]

Do you have access to a L/K ? It would help you get the proper dimensions for the program and elevate most of your issues

 

[bumthum]

Do you have access to a L/K ? It would help you get the proper dimensions for the program and elevate most of your issues

I wish, but no. I'm doing this all from my apartment and my profession is presently unrelated to engineering or manufacturing.

 

[adam01364]

That's an amazing post.

 

[undeRGRound]

Well done, it's nearly finished.

But as they say, the devil is in the details

 

[TNTRAILERTRASH]

This is a lot of work for a well known jam-0-matic. My sister used to carry one. Never could get it through a full mag without a jam, Now she packs a LCP2.

 

[bumthum]

This is a lot of work for a well known jam-0-matic. My sister used to carry one. Never could get it through a full mag without a jam, Now she packs a LCP2.

Well, I own around 16 Ravens at this point and, though there are only three that I shoot, I've actually never experienced a jam or stovepipe, even with my hand loads using flat point bullets. Generally, I consider the Raven design to be the most consistent and functional firearm in its class. Obviously there are likely exceptions to that, but I'm not sure the Raven design is a well known jam-o-matic (unlike the other Ring Of Fire guns). Even period reviews gave it solid scores, but your mileage may vary.

Either way, the design fascinates me, I think it played a large role in US firearm history, and allowed a lot of lower income people to defend themselves.

 

[Rerun]

Bravo Zulu!

Outstanding series of articles!

Really enjoying your work!

Never give up!

Rerun

 

[moona11]

I wish, but no. I'm doing this all from my apartment and my profession is presently unrelated to engineering or manufacturing.

I bet its still a fun little project. I trash those guns all tthe time but have fun.

 

[adam01364]

FWIW, my experience with Ravens has been that jamming in an unmolested pistol was always mag related.

In the past I've acquired some "polished" feed ramp Ravens that would never work consistently.

 

[bumthum]

FWIW, my experience with Ravens has been that jamming in an unmolested pistol was always mag related.

In the past I've acquired some "polished" feed ramp Ravens that would never work consistently.

I've seen a few Raven mags that have been so heavily used that there is a groove worn in the follower. I suspect a lot of people never took the time to buy extra mags for their pistols and the magazine quality definitely shows signs of decline through the years of production. I'm sure some are very much responsible for misfeeds, etc.

I have a Raven that was found in a water soaked abandoned car. Its heavily corroded among other issues. I was going to use it for a reliability test and haven't cleaned it or done any maintenance. At some point in.the near future I'm going to run it through its paces and see what happens with jams, etc.

 

[FlashBang]

Looks good! After you get the frame all sorted out you'll need to address the magazine. 3D mags are cheap to print, just need to get all the parts to proper scale etc. I 3D print 20 round AR mags and they work great. Biggest issue is finding the springs for the 20 round mags I print. The cost to print them, including the floor plate etc etc is under $1.50 for the filament. I'd love to get your files and print settings when you get it all done.

 

[undeRGRound]

Looks good! After you get the frame all sorted out you'll need to address the magazine. 3D mags are cheap to print, just need to get all the parts to proper scale etc. I 3D print 20 round AR mags and they work great. Biggest issue is finding the springs for the 20 round mags I print. The cost to print them, including the floor plate etc etc is under $1.50 for the filament. I'd love to get your files and print settings when you get it all done.

In another thread's "drift" he seemed to indicate that it would be available

 

[bumthum]

Looks good! After you get the frame all sorted out you'll need to address the magazine. 3D mags are cheap to print, just need to get all the parts to proper scale etc. I 3D print 20 round AR mags and they work great. Biggest issue is finding the springs for the 20 round mags I print. The cost to print them, including the floor plate etc etc is under $1.50 for the filament. I'd love to get your files and print settings when you get it all done.

There's an interesting concept, but the Raven design doesn't leave much room for a thicker magazine body. Probably something to look into once I get this done and functioning.

But yes, as @undeRGRound mentioned, I do plan on making the files, etc, available upon PM request once I get everything done and make sure I'm not passing around files for an accidental hand grenade.

 

[bumthum]

Basics of Fusion 360 and CURA Work:

So, for an object that is mostly symmetrical, I like to layout the general outline I'm seeking on a central plane and then extrude the sketch in both directions. Below is Sketch 1 of the current iteration of my frame. Most of the profiles seen in this sketch are extruded in both directions, but there are a few that are only there to give me a visual of how thin the material will be once a cut is made into the main body of the object, the pocket for the Sear Assembly is a good example here. The pocket for the Sear Assembly is shown here, but I actually draw a circle on the upper plane, after the main shape is extruded, and then I make an extrusion set to "cut" to the appropriate depth. You can see the Magazine Catch pocket has quite a few profiles, this area is still being actively worked.

Once the main body is extruded then I start making extrusions set to cut at various depths to remove material where it needs to be removed. Fillets are added to the edges I prefer to be rounded and all other edges remain as drawn. This body was made using the Sketch 1 shown above.

Once I get all of the desired changes made for a given iteration, I go to file and select "3D Print". You drag and select what you want printed and export it to CURA. CURA wasn't one of the built in programs that Fusion 360 had in it, but setup was as simple as selecting the CURA executable when I was prompted and I was never asked again. The result shows up in CURA and, to make a functional print, you should set it at 45 degrees to the bed. Without going into the details, trust the other 3D printing gurus online and just set the object to 45 degrees. It increases the cross section of the shear plane and generally results in the best split of recoil forces being transferred into the frame by the pins holding your operating parts. It's trig, but it's also intuitive. I won't cover settings here, if you're interested, you can PM me when I finish this project and a README will be included with the other files.

So that is the very basic Fusion 360 and CURA rundown... not a detailed account. I was able to obtain 3 parts kits with barrels and most of the small parts. Only one kit was for an MP-25 with a rotating safety, the design I chose to base my Ghost Raven on, but I have a pile of spare Raven parts, so I have room to experiment. You may have noticed that none of these frames will accept a barrel in any way, that problem is being solved, I just need to time to think about it. I see that one or two sellers on Gunbroker are putting up kits with the barrel, I recommend jumping on one of these if you're interested in this project, they are also available on some e-shops, but at much higher prices.

The next iteration will likely have all of the other details solved and incorporate a method for mounting a barrel. I'll probably CAD up what I think the barrel should look like and start working the frame around that. There may be some math involved at that point, I need to make sure I have some good way to mechanically fix the barrel in place without leaving the frame too weak in that area.

Standby for further...

 

[here]

So regarding the potential weak frame around the barrel perhaps the solution lies in making a 3d model to be used as a mold to cast a new metal frame. Since these are such small gun printing the frame 0% infill and the making a lost wax mold wouldn't take that long or use a-lot of metal even if the choice of metal was more expensive than PLA+. As for machining the cast you could also design a set of file brace jigs to allow for hand machining similar to the diy aluminum glock rails.
Hec you might end up with a stronger than stock frame.

I do wonder if the cast frame idea I outlined is better for gun like the titan do to the differing barrel setup.

 

[bumthum]

So regarding the potential weak frame around the barrel perhaps the solution lies in making a 3d model to be used as a mold to cast a new metal frame. Since these are such small gun printing the frame 0% infill and the making a lost wax mold wouldn't take that long or use a-lot of metal even if the choice of metal was more expensive than PLA+. As for machining the cast you could also design a set of file brace jigs to allow for hand machining similar to the diy aluminum glock rails.
Hec you might end up with a stronger than stock frame.

I do wonder if the cast frame idea I outlined is better for gun like the titan do to the differing barrel setup.

Well casting is certainly possible, but the point of 3D printing the frame is to make it more readily accessible. I get it, this isn't some FCG-9 project where I'm trying to arm the huddled masses, but I think casting metal is beyond the reach of the average hobbyist.

I got all the frame squared away except the barrel mounting issue, I'm still pondering it, but a solution is always possible. All those years of school won't let me down.

 

[here]

I think casting metal is beyond the reach of the average hobbyist.

imho small scale one off plaster of paris style Al casting isn't beyond the average person with a 3d printer since you'd need one any way to make the mold. Now large scale high efficiency casting is far beyond your average person. All you would need is a can to pour the plaster in and submerge the plastic frame, a butane torch, melting pot and pliers, along with some other small things.
The pliers, crucible, and torch can be replaced by an old pan and common gas kitchen stove. So as long as its not an every day thing its a fairly low barrier of entry

Also as far as im concerned the point of 3d printing is to avoid paper work.

 

[bumthum]

imho small scale one off plaster of paris style Al casting isn't beyond the average person with a 3d printer since you'd need one any way to make the mold. Now large scale high efficiency casting is far beyond your average person. All you would need is a can to pour the plaster in and submerge the plastic frame, a butane torch, melting pot and pliers, along with some other small things.
The pliers, crucible, and torch can be replaced by an old pan and common gas kitchen stove. So as long as its not an every day thing its a fairly low barrier of entry

Also as far as im concerned the point of 3d printing is to avoid paper work.

Yes yes, I suppose, but you can also buy a Harbor Freight mill for ~$800 and mill a frame from aluminum stock as well... if "off the books" is what you're looking for and extra work processes aren't a barrier for entry.

I view 3D printing as also a way of democratizing the gun hobby in a way that opens it up to the masses, including the relatively unskilled. Someone with basic hand tools and a 3D printer ought to be able to make this Raven in an apartment... or in a hobby room.

 

[Twisty]

Yes yes, I suppose, but you can also buy a Harbor Freight mill for ~$800 and mill a frame from aluminum stock as well... if "off the books" is what you're looking for and extra work processes aren't a barrier for entry.

I view 3D printing as also a way of democratizing the gun hobby in a way that opens it up to the masses, including the relatively unskilled. Someone with basic hand tools and a 3D printer ought to be able to make this Raven in an apartment... or in a hobby room.

Just how messy is this process?

The reason I ask is you said in an apartment. As a landlord I had a tenant who had a motorcycle disassembled in the living room. He was using the kitchen sink and dishwasher for parts cleaning. I kicked him out and kept his deposit.