M72 LAW 3D printable

I improved the accuracy of the A7 sight based on some lower rez information. Still not perfect but its as good as its going to get since I'll be printing this in resin and I need it thicker for strength, since this thing is going to flip up with a spring. Perhaps I'll drill a hole down the center and glue in a metal rod.

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TazMan2000
 
I took apart my Creality CR-10S to clean it up, put in a new Bowden extruder and leveled out the lead screws on the Z-axis shafts by shimming, along with bending parts to a right angle. Now it prints better than when it was new and measures perfect to the dimensions of my design.

Here is the halves of the rear extension slider for the M72.

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This is going to save a bit of time post processing.

TazMan2000
 
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The arming thingamajig is installed. The draw may be a bit long though, but since it's glued in, I'm not going to change it.
Through the clear tube, you can see the styrene strip that I'm using as a bushing for the sliding inner tube, so it won't scrape off the paint. Next is working on the flip up sighting system.

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TazMan2000
 
Filled and primed. I tested out the flip up springs and they work beautifully, but took them off for painting. I still have to attach and adjust the mechanism rear cap. I will eventually design the front cap but I want to make sure the important stuff is done first.

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TazMan2000
 
I'm not posting a video, but trust me, the sights pop up when extending. I made a front cap, and am working out a way to make the strap that holds that cap in place. PLA is definitely not as strong as metal, so I'm going to have to modify the strap to add webbing for a shoulder strap.

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TazMan2000
 
A quick coat of Tamiya Olive Drab. I still have to add the rivets to the sight holders and the tube.
I printed out the sticker instructions several times until I managed to get just the right shade of olive drab on regular bond paper. Unfortunately the picture shows it really off, but it is just about spot on with my eye. I have a full sheets of sticker material that hopefully has the same properties as the bond. Also, when I coat it with Testors Dull Cote, I hope it doesn't change the colour too much.

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TazMan2000
 
Almost finished. The strap that holds the front cap in place is not accurate to the real thing, but the strength of PLA is limiting, so I cobbled something that works. I still need some webbing for the shoulder strap. Also, I still have to add a piece of plexiglass to the front sight and get some printable clear stickers to print the red graduation length markers.
Sorry about the quality of the photos, as they are from a cell phone and the lighting wasn't the best.
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TazMan2000
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I'm considering this M72A3 done. A few things I'm unhappy about, is the aluminum channel not being black. Adam Savage noted in his weapon build of some sort of blackening solution with worked well at first but seems to rub off with a bit of handling. If I were to try and make this more accurate in the future, I would try and electroplate it or acid etch it. But even that may wear off with repeated collapsing/and extending the prop. Another thing is that that the graphics were printed on an inkjet and editted with MS Paint. The staircasing is evident, but for a PLA prop, it will do. I suppose if I wanted to make it more realistic looking, I would put in a tube in the channel to simulate the ignition train. I still might...but I have other projects on my bench, including the M72A7.

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I was trying to replicate one of those metal ID plates you see on the M72A7 and up models. I wasn't going to chance inserting a piece of tin foil into my inkjet, so I printed the graphic on a piece of clear film stickers you can get at Staples and glued it onto the non-shiny side of a piece of aluminum foil. It turned out pretty good, however, it will still need to be glued and coated with a dull coat, so some of the advantages of reflectivity will be diminished.

The markings are actually stamped into the plate, so I tried using a grey colour to simulate that. Unfortunately, it didn't work out that well. Good enough for a prop though.

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TazMan2000
 
That looks really good, I reckon (esp from a metre away, no-one's gonna be able to tell).

I've used the same idea to do dataplates (using Avery brand self-adhesive labels; on the work laserprinter); one day I'll try out their silver foil labels, as I suspect they'll be better/easier, but they are quite pricey.
 
That looks really good, I reckon (esp from a metre away, no-one's gonna be able to tell).

I've used the same idea to do dataplates (using Avery brand self-adhesive labels; on the work laserprinter); one day I'll try out their silver foil labels, as I suspect they'll be better/easier, but they are quite pricey.
Thanks.
I never saw the foil labels for letters, but I saw them for wine bottles. They were indeed expensive.

TazMan2000
 
The M72A7 version is finally done. It's similar to the one that Sarah Conner uses in the last Terminator movie. This one has a bit of a different olive drab paintjob than the original M72 LAW, so I found that Rustoleum had a satin olive drab meant for outdoor furniture. I'm not sure if I bought a bad spray can, but I had nothing but issues with this one. It would stay tacky for days, and tape would take off layers. Then on another day it would go on without issue. I've never had this problem with any other Rustoleum product, except one time with their sandable primer where nothing would come out but air.

Then, I tried using a vinyl sticker product that was meant for inkjet. It did not like any sort of coating to protect the ink. Even though I waited days for the ink to dry, it would still rub off with the lightest touch. I tried the Testors ink bonder for inkjet decals, but it wrecked the ink. Anything else would cause a white film.
Whatever....I'm done.

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Even with a matte clear coat, the "metal" plate still looks great.
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Not sure what happened with this photo. The spotty paint job is not evident with the naked eye.
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TazMan2000
 
Oops. I forgot to glue on one of the most critical parts that identifies this model. The Picatinny rail.

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I've seen some of the picatinny rail parts with white raised lettering on top, others without. You would think white would stand out in the field...but then again, wouldn't the painted metal plate reflect light? I digress.

TazMan2000
 

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