Making a MacGlashan Tribute Gun

[Killbucket]

What's a MacGlashan?

Here's a link:http://www.macglashanbbgun.com/

There's a slim chance you may have used one of these at a carnival, attempting to shoot a little red star out of the middle of a chuk of paper.
Technically possible, but highly improbable...You had to draw a nearly perfect circle to remove "every bit of star", mis ONE shot, and your math goes kaput on you.
I have GREAT memories of being VERY frustrated with this process. Had I $100, the random-toothed carny could have had every dime, because just shooting a "machinegun" with John Wayne-COOL spade grips was a rush for 9-year old me.

The military briefly used these for gunnery practice (please, follow the link, read the page!) for new pilots/gunners, and they have all but vanished from pop culture.

It's a good bet that if your Grandaddy scoffs HARD at your airsoft guns, he won't be able to stop himself from at least trying something looking like this.

Huggers of the P90 series airsoft guns are allowed a bitty smile, the MacG was a top-feeder.

But they are also afforded a sickening halt, as I'm going to just do a quickie, and build a box around a Beta Spetnaz AKM.
Because they're cheap, and I'm going to make the Ak part of the design "disposable"...OK, "field-swappable"!

[Killbucket]

So after perusing the few pics we can find, I've determined two things:
A: An approximation is going to be just fine, because most humans won't be carrying a real one, and be able to compare them.
B: No CNC'd parts. Putting too much thought into this would be a shame, unless I wanted to make a "Museum Dummy". I don't. This is going to be a fun machine!

I'll still give it a fitting paint-job, tho.

CRITERIA: The gun has to slip out without grabbing any tools. The gun has to be minimally modded, so backups aren't a chore. I've removed the furniture and the selector lever, and locked the gearbox into full-auto mode with a spot of ABS glue. Design will be such that placing the stripped-down AK into the box results in the trigger being guided back by a ramp, so it's always in fire mode as well. An electric solenoid relay will turn the AK on and off with presses on the fire button. A small toggle switch will serve as a safety.

First off, a chunk of scrap cardboard and a few tools are set out on the kitchen floor, to determine the "package"..

If you browse the InnerTubes much, you've seen cardboard guns aplenty. I laugh too. Find a guy who's made 20 or so, and you might have a pretty good engineer on your hands.

Actually, I had the fan going, and the dogbowl made a great paperweight.


Determine where the barrel centerline will be, and draw everything from that reference, or "Datum". The MacGlashan has some gear that protrudes from the top-front. Look under the front of thre sight tube, and you'll see what I'm talking about. I'm going to exploit this feature, and allow the top of the AK to be this part. This will make the casing shorter top-to-bottom, for a better length/width ratio.

I've determined the side panel size, and made some 1.75" wide strips two make the main box sides and ends.-So far, all material's been cut with a Stanley knife blade. Two deep scores in the sheet, bend and snap.


This poor BetaSpetz has been subject to about four paintjobs, and as many custom shells.


Left it like this overnight. Applying the "Just Walk Away Human" rule, so the bonds will all cure up perfectly aligned. I could have made the box a bit narrower, but I wanted plenty of room inside for gas gear if It decide to add that in later. But I think it looks close enough!

Notes:

Oatey ABS cement was used for gluing. I pour it into Wilton cake-decorating bottles for MUCH easier application. Note the small section of aluminum extrusion on top of the part here (a 1919 sideplate from another build). I use it to make sure my parts are at right angles where needed. Eye-balling it doesn't work.


More coming...

[The Saint]

Wasn't the original MacGlashan ammo 8mm bakelite? I recall reading that somewhere.

[Killbucket]

Originally Posted by The Saint

Wasn't the original MacGlashan ammo 8mm bakelite? I recall reading that somewhere.

.177 cal:
"BBs were conventional commercial .177 caliber copper-coated steel shot."

http://www.macglashanbbgun.com/Histo...7/Default.aspx

Reading on, I must be pretty lucky to have touched one at all, let alone fire it. There were less than 1000 built, I think.

I sold my M2HB' s waaaay tooo cheap..less than 500 of anything isn't many.

[Killbucket]

You can see how the nose of the Ak is located here. Glued-in spacers hold it centered in the body. When I do th final CAD, I'll narrow the casing and eliminate the need for spacers.


I added a small tab at the front to close the slot for the barrel. Not really needed, because a front plate will cover it up.


See how the front sight on the AK sticks out the top. I'll make a small box to hide it.


I allowed the motor to stick slightly out the bottom. I'll argue it's for cooling. Actually, I'd prefer to have the casing not be as tall as it is, so it's the product of compromise, not design criteria.


Look close, and you'll see the tab holding the trigger back. I'll run a feed tube to an adapter plate, plug a wire harness into the AK.

Now scouting for a barrel shroud. The original is tapered, I'd like to find a way to preserve that detail. Hmmm...

[Panzerfaust]

Very Cool!
Is it acrylic sheet that you use? If yes,what kinf of adhesive you find to be the strongest to bond the parts with?

[Killbucket]

Originally Posted by Panzerfaust

Very Cool!
Is it acrylic sheet that you use? If yes,what kinf of adhesive you find to be the strongest to bond the parts with?

.118" / 3mm ABS sheet from www.interstateplastics.com
All bonds are made with Oatey Black ABS Plumbing Cement.
There are better glues, but this is the most user-friendly, and results in very string bonds.

[Panzerfaust]

Thank You!

[Panzerfaust]

Thank You !

[Killbucket]

PVC sheet from the same place is lighter (to ship, smile) and is reasonably durable.

[Panzerfaust]

I will see if I can get some of this stuff through work ;o)

[Killbucket]

Originally Posted by Panzerfaust

I will see if I can get some of this stuff through work ;o)

YouTube - King Missile - Take Stuff From Work
King Missile ROCKS...and you just reminded me of their best work.


______________________________
The free pattern bin:
http://www.air-sharp.com/free_patterns.html

[Killbucket]

R&D Notes.
Finally at the point where I've started measuring the box I've made around my AK here, and comparing that to the pics of the real thing.

I printed out the side view pic they have up, that shows the sidecover removed.
Nice that they took that particular picture. There's standard hardware shown inside...

So by guesstimating what size hardware I'm looking at, and comparing the depicted vs actual size, I determined that my printed page was 3.13 times smaller than actual size.

Now it's just a simple process of measuring features on the printout, and multiplying by 3.13x.

I came to the conclusion that the MacG is a box measuring:
APPROXIMATELY 1.5 x 16 x 5.625.

Now I'm going to take my M14 mount CAD:



(print this page on 8.5 x 11, no margins, 300dpi, using ACDSee preferably, because it's free and friendly. You'll have parts to start building anything around an M14's gearbox and hopup.)

And drop it into a box that size in TurboCAD. Meanwhile, I'm going to knock the AK version down, and put the bits back into the goodie bin.

[Killbucket]

Rather than construct a pintle, I just made a standard 1/4"-20 threaded lug on the bottom.


So I can just mount it on a standard Velbon tripod.