3D printed MG34 project idea thread.

[Dracul]

I'm just creating this project thread as to not hijack another thread. This is likely to just be a one-off pet project of mine, and it will might WILL take awhile. I'm no expert engineer, so I will have to desecrate the authentic design of some of the parts. Simplicity over authenticity here.

I came across a skilled modeler who made a high-detailed MG34 model intent for 3D printing and even printed one out himself, and bought a copy of the models from him. I originally wanted to print it as a static prop/replica, but I've decided I wanted to challenge myself, and make it accept airsoft internals. 

This is the modeler's work on the MG34 files I'm using (I know it has a Star Wars name, but the SW prop was just a MG34 with a few add-ons):  www.flickr.com/photos/138687445@N03/sets/72157671429051850 

I'm basing it off of V3/AK internals, as I have a V3 fusion engine collecting dust. I just need a new hopup and inner barrel. This makes things easier as I don't have to worry about hiding a huge battery or aligning the pistol grip to screw to the gearbox. This should be as easy as dropping in the internals and maybe screwing on a brace or two.

I came across three big problems I'll have to figure out:
1. Figuring out how to incorporate the AK selector switch.
2. Figuring out the mag situation. 
3. Making it easy to break down the gun to get to the internals easily. 

Here is a pic of the models assembled: 


And a cutaway view with airsoft internal models in yellow:


Its going to be a challenge, but if the internal models I'm using are to proper scale, it might be easier than it looks. I've gotten good at figuring out tolerances. 

Preliminary solutions:
1. Maybe have the a reduced or cut down AK selector lever, or model a simple one masked as a random screw or bolt, or move the charging handle down to the selector lever axis and use that as the new lever. 
2. I'll have to add mass to lower receiver, under the hopup, to accept a common drum or MG mag and some how offset and angle it to feed under the gun AND to be masked by a normal looking 34/32 drum. 
3. Model in holes to accept large push or screw pins to the forward section of the lower receiver, like any other gun that can be taken apart. 

This is a pretty big undertaking and its all in the idea and planning stages right now. No doubt a huge money, time, and material sink, too. If this actually ends up working, then I'll contact the modeler and see if he will accept compensation to allow me to sell kits based off of his model (and I'd model it further to accept common AEG internals as well). 

[2nd Bat]

The feed system and hop up are always the biggest challenges. But you know that. The other huge challenge is that the pursuit of perfection in these things with regard to fidelity of demensions is a project completion killer. Some reasonable compromises have to be made if you're gojng to wind up with a functional, durable skirmishable gun. Remember that you're goal should be something that is recognizably a German machinegun at airsoft ranges.

[adrg]

As you might have noticed from my PM I am working on a complete similar project.
One thing that you might notice is that the V3 gearbox is a little too long in front to accomodate within the hand grip mount. In my trials the handgrip is moved 2-3 cm backwards.
About the mag - I am looking mainly at a top load because I was looking for a AA version with the saddle drum on top. But you can configure a piece that would mount on the ejection port underneath and use a MG 42 drum mounted side way. It will have a weired tub for feeding.
Also you might want to take a look to Ares new slim motors for V3 which will fit better in the handgrip as they are shorter enough.
I’ll send you a PM for some questions.

[Dracul]

Now that you mention the saddle drum, that might actually be easier, but I'm afraid the hop-up might not work properly when upside down... If thats not a problem, then it would make life much easier. They look more simple to model, insert drum mag electronics, without worry of the side drum mounts being thin, and more authentically mounted (without doing anything weird with the underside of the gun). Not sure how common the AA config was for WWII standard infantry, buuuuuut, it would definitely be easier to work with.

As per our PM convo, it seems like you are modeling yours based off a real-steel body and its individual to-scale parts. This one is more or less a single solid model, I don't, or shouldn't, need to move the handgrip at all. Though, I am going to have to add mass to the hand grip for sure. Hopefully, it wouldn't be too much of a distraction (despite going to have an air tube coming out of it regardless...).

[Dracul]

I just did some research on the saddle, not drum, but mag. The "Patronentrommel 34" It was actually a spring loaded mag, instead of just a case to hold a belt.

Researching it, I feel like its the easier way to be functional and reliable, but it would require a near complete remodel of the feed tray cover. Another con to this is, it was only really used as emplacements on vehicles and anti-air use. Photos of it in use seem to be from the pre-war period, latest in Poland.

While the research weighs against leg infantry use, which is no doubt what I'd be using an MG34 for, I'm likely to go with the PT34 mag, as per the primary ideal of simplicity over authenticity. I wouldn't be doing anything crazy like alternating bullet loading from each side, like the PT34 was capable of, one side of the mag is still big enough for drum electronics and plenty of ammo.

[adrg]

Top feeding is actually quite difficult and you need either a dedicated hop-up or one from P90 or I think there is a ST -57 that also has a top load. You can source these, but aligning with gearbox and guessing the nozzle will gonna take some time.
It won’t work with a V3 hop-up or most hop-up. The only hop-up that might be easily converted to top load are the A&K variants for SVD/M43/60 etc. these have a circular nub. All needed is to get a hole direclty oposite the original one and reverse the hop-up position. Yet - this is a delicate procedure as if this gets very slightly off - you’ll need to try with another. It still can be used for original purpose though.

I totaly agree there isn’t a direct use for a saddle drum in infantery. I was looking for that as a variant that gasn’t been done yet.

If you are searching for DLT -19 (Starwars name) you can find some printings that are actually really close to the original MG34. It is just they won’t print only parts or sell the models.
I am working on 2 technical solutions - both AEG:
1. A&K SVD wich basically means the body if the SVD is slimed to get into the MG34 body. Still requires large adaptations of the body and it isn’t the most common AEG. I bought this cheap at about 120 EU few years ago.
2. V3 gearbox with one hop- up (not decided yet) with top or lateral feed (I have found some bare hop-ups for Sterling). Still a mater to decide how to fix all these in line.

It seems there is enough space for some 11.1 V LiPo in the back (using 1.25” /35 mm pipes).
Right now the winning version seems to be the V3 with slim motor.

[Dracul]

Well, damn, back to the under-gun idea for the mag. Oh well, it will easier on modeling anyway.

The models I bought was the Star Wars model, but the guy offered the SW add-ons as separate parts with it, leaving the base MG34 models as a proper MG34.

I'm using a fusion motor, a Wolverine SMP, so space needed is fairly limited, even the battery takes up little space.

[adrg]

You’ll get more than enough space for the tinny battery.
I would run the line in the back of the stock. I was thinking also using HPA and actually using a small 50mm diameter tank in the back in place of pipe linking to the stock.
But I ditched the idea because of the small volume.
A great place to put a slightly larger tank is in a ammunition box used separately from the replica - like in a stationary position

[hunterj]

Dracul did you ever finish this? I have a 3D printer and would love to print a airsoft MG34.

[2nd Bat]

One of semi active members up in Canada (Steve Miner) just posted on his Facebook site his impressive video of his FJ42 custom which he created via 3D Printing. Very impressive. I truly hope he offers the components of perhaps the files to others.

[hunterj]

I have been following his FG42 and his G43 builds. They're extremely well done, but do not seemed to be geared at all towards production besides single builds at a time. He basically 3D prints the entire gun from the ground up. They look fantastic though.

[2nd Bat]

I am not super up to date on 3D printing but my understanding is that even with fairly expensive machines the print time is extremely slow (several hours for each part?). Hence a multi part print for something like an MG 34, G43 or his FJ would be a lengthy involved process once you had it all worked out. Naturally while it's printing you can be doing other things like sleeping and dreaming up other projects. Not a great medium for mass production.

[rullow]

basically the part of the size of receiver of MAS49 or MAT49 is the whole days print - depending on quality requested....
however usually you print overnight and then you spend enough time processing the parts...so the time you spent printing is not such issue..
it would be if you would like to make it in series....

[adrg]

I agree - mass production in home 3D printer is still expensive and time consuming. for a MG34 you can get some reproductions from plastic or wood fairly cheap (actually might be cheaper than 3D printing itself + lots of extra work o get it finished). About using the V3 in the SW models widely available - this is doable, but with slight alterations. For example - the angle of the handle needs to be slightly adapted. I was testing with Ares slim motor which helps because it has the mount only on the cap. One other complication is that the cylinder is sitting higher than the ax of the outer barrel - which means the cylinder head should type M14 (V7) to better align the inner barrel with the MG34 ax. I stopped working at these for couple of years now due to lack of time - but what I tried so far:
1. V3 gearbox - the most available - requires some small alteration of the MG34 body and GB to proper align and work differently with the MG34 ax. Also it will be difficult to utilize a AK 47 body to hold everything together (meaning the 3D print must be augmented with support structure).
2. A&K SVD gearbox - a nice and slick GB. Requires re-positioning of the trigger. Otherwise you can successfully use the whole SVD in your build to keep external alteration as minimal. Hop-up can be relatively easy adapted to top feed if you just fill in the whole from underneath and do one from the top. Still - overall the gearbox is a little exposed in some areas and protruding. Overall this is my most advanced model I did.
3. MG42 GB - I have found a shell in one of the EU shops, but I still need to do some parts to complete the inner GB. It sits nice, handgrip not completely on the correct angle, but can be managed also the hop-up is directly linked to the GB nozzle which makes the overall build easier than working with separate parts. Specifically the GB is full auto only which is different than what was the original model. This is my most underdeveloped model.
4. - Looking right now to the AGM M1918 GB - again shells are available here in Europe in none shop - but not the entire GB - so a lot of rebuild is required.
5. I was juggling with the idea to use a Real sword Type 97 gearbox - but this is very difficult to source and very expensive. It is very compact and slim with lowest nozzle sitting I ever saw (if you can find it). But I think I will keep that for another project (FG42) as there aren't many out of the box GB to fit that body.