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 Post subject: Q: "Can you tell me more about Pulse Rifle shrouds?"
PostPosted: Fri Dec 05, 2003 8:01 am 
Regarding my own fiberglass shroud project, we are close to finishing shaping the master and begin the mould making process.

I have a question for the PR-Expert-Types:

What is the purpose of the arrowed feature on the shrouds ? On the screen used working aluminum shrouded PR, was this just a feature beaten into the shroud form, or was this a clamp/brace of some sort ??

If it were the latter, we will build a metal piece separately. If it were part of the shroud with no particular purpose, then we will need to add that to the master.

SOMEONE's RECASTED SD's SHROUD

http://www.menatarms.us/Presentation2.jpg


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 11:11 am 
MAA,

Taking the photos of the Bapty PR that I saw as reference I can say that the detail wasn't beaten into the aluminium shrouds, they were additional pieces riveted to each shroud half.

Hope that helps,

Harry.
<IMGSRC="http://www.triotech.demon.co.uk/hhacabanner.gif[/img]Edited by: [url=http://pub217.ezboard.com/bthealienslegacy.showUserPublicProfile?gid=harryharris>Harry Harris[/url] at: 12/5/03 4:13 am


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 12:28 pm 
Quote:
Quote:The point being that it's one single bracket which passes under the shroud and helps to secure it together.
That's what I thought at first, but then if the countersunk rivet theory is right (and I think that is what Spellbinder99 said the fixings on that part were) then as MAA said, it would be impossible to disassemble the shroud for maintenance of the Thompson.

Actually if you need to hammer those rivets from the other side wouldn't it mean that you couldn't build it like that in the first place?

The plates that do hold the shroud halves together, on the upper front face of the shroud for example, are pop riveted to one half of the shroud, and screwed to the other half with self-tapping screws.

Harry.
<IMGSRC="http://www.triotech.demon.co.uk/hhacabanner.gif[/img]Edited by: [url=http://pub217.ezboard.com/bthealienslegacy.showUserPublicProfile?gid=harryharris>Harry Harris[/url] at: 12/5/03 5:30 am


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 1:56 pm 
Thanks H/H !!! :)

That's what we figured (in case everyone thinks I'm referring to my imaginary friend -- I hired a sculptor to work with me on making the shrouds).

As we all know most kits out there now has this feature moulded-in (e.g. G&P Airsoft PRs). I just wasn't sure about the Bapty PR though -- having never seen it up close and personal; however, we did have the following image for reference:

[img]http://www.menatarms.us/Presentation3.jpg[/img]

Anyone know exactly how these two piece metal brackets(?) were secured onto the shrouds ??

"We few, we happy few, we band of brothers...For he today that sheds his blood with me
shall be my brother."


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 2:09 pm 
It was hard to tell on the Bapry PR because of all the paint on the shroud which looked like it was put on pretty thickly and/or in many coats.

They looked like they were held on with rivets, but not the common 'pop' rivets that you normally see as they have heads that are slightly raised in a dome shape.

The fixings on the Bapty PR were flush with the surface, leaving nothing more than a grooved ring:

[img]http://www.encom.demon.co.uk/graphics/opr03.jpg[/img]

Spellbinder99 is your man for fixings and the like, and I do remember a discussion over on the old board about it but I can't remember how far we got with identifying how it was done.

Harry.
<IMGSRC="http://www.triotech.demon.co.uk/hhacabanner.gif[/img]


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 2:17 pm 
It could be a countersunk rivet(either steel or copper) that is put in from the outside and hammered on the inside to hold it in place. At least that's how I plan to attach the ones on my shroud. :)
www.rivetsinstock.com/rivet09.htm
fdoveraker@att.net


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 2:20 pm 
Surely it's an 'it', not a 'they'? The point being that it's one single bracket which passes under the shroud and helps to secure it together.
Mike


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 2:25 pm 
Ah!

But using rivets would make it hard to take the shrouds off for service, which in the past haven't been a real concern. However, with growing popularity of Airsoft and guys like ARMAT who wants to make actual firing PRs, wouldn't another type of fasteners be better suited ??


"We few, we happy few, we band of brothers...For he today that sheds his blood with me
shall be my brother."


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 3:10 pm 
The way the ones I have right now are will be solid, in that they will run underneath the shroud and hold onto both sides.
To act as a clamp. Otherwise as two separate clips I cant see how they would do much in the way of functionality.
Accuracy be damned I am going to use button head hex drive screws for all my fastening needs. They could have very well used a couple of countersunk hex drive screws in that piece and the holes gotten filled by several layers of paint.
Like MAA mentioned the shroud on working guns, airsoft or otherwise ;) needs to be removable for service.

More later.

Matt


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 3:51 pm 
As a couple of people have stated - I think they may just be pop rivets - dis-assembly won't really be a problem as drilling out a pop rivet is easy and they only cost pennies - a very cheap fixing.


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 4:08 pm 
But you don't need to drill them out, they can stay on because it's not a one-piece assembly.

As I said earlier it's two parts, at least on the Bapty PR that I saw:

[img]http://www.triotech.demon.co.uk/PulseRifle/pr_detail.jpg[/img]

I'll check my other reference on this though because as we know, no two Pulse Rifles were exactly the same.

Harry.
<IMGSRC="http://www.triotech.demon.co.uk/hhacabanner.gif[/img]


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 4:15 pm 
I believe the clamp was initially one piece to hold the shrouds together. The firing pulse rifles however need cleaning and maintainance on a daily basis. So the shrouds and attachement pieces were modified for easy access. From what is visible form the pictures of the pictures on Harry's site and the following picture I'd say it is possible to disassemble the (firing) PR without separating the two shroud halfs:
Image
The disassembly procedure seems to be like this:
- remove magazine
- unscrew the Thompson barrel
- pull out the Grenade Launcher (including the Barrel Vent, Thompson foreward Grip holder and Thompson barrel) to the front
- slide out Thompson barrel to the rear of the GL-assembly
- unscrew the lower rear clamp
- slide lower Thompson receiver out to the rear (no, if you check the pictures on Harry's site you'll see there is enough clearance for the levers on the side)
- remove main spring and chocking pin
- remove bolt
- slide out upper receiver to the rear

Cheers,
Stefan

Edited by: [url=http://pub217.ezboard.com/bthealienslegacy.showUserPublicProfile?gid=bugstomper>Bug Stomper[/url] at: 12/5/03 9:17 am


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 6:19 pm 
The GL-assembly attaches at two points to the Thompson:
- to the barrell via the support triangle (which is in fact a part of the barrel vent)
- two screws with 9mm spacer tubes that connect the shotgun receiver to the foregrip rail of the Thompson (prototype 10-hole version). The spacer tubes were replaced by a solid block with the later models.

The foregrip rail slides from the front into the upper receiver of the Thompson and is locked in place when the barrel is screwed in. Thus you get a very solid connection (I think Stephan, Kevin and Neil can agree ;) ).
Now when you unscrew the barrel you can easily remove the whole GL-assembly toward the front.

Cheers,
Stefan

Edited by: [url=http://pub217.ezboard.com/bthealienslegacy.showUserPublicProfile?gid=bugstomper>Bug Stomper[/url] at: 12/5/03 11:25 am


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 6:44 pm 
*Sigh* ...I could look at that picture all day..:lol:

Oh wait I kinda do..:P ...sept my shroud isn't aluminum...:roll:

So Stefan are you saying that the PR can be Disassembled without "Un-Sandwiching" the shrouds?...Sounds interesting....I like it...

I need to think about that in regards to mine. The thing goes together like a puzzle box. if I were to do it like that all I would do is remove the grip frame from the upper, dismount all attachment points and slide the whole thing out from the front But the stock may be a problem going out front. My worry is how dificult "Unscrewing the Thompson barrel would be. In a real gun those babys are on TIGHT!

....and barely discernable is the extension, still on the foresection of the vent that the stock thompson barrel screwed into, what had the blank adapter mounted to in thevery tip.

The pic before, of the clip definately shows countersunk "somethings" painted over.

Matt


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 7:28 pm 
Matt,
I don't think it will be possible to slide the Thompson out without first removing the chocking pin. And to remove the chocking pin you need to remove the lower receiver first.

As for the blank firing adapter - I'm pretty sure there is no such thing. Even if you thread the barrel, you won't be able to screw something onto it without getting a much larger diameter than the barrel (especially if it needs to withstand the gas pressure). However, not even the raised area that is normally located below the front sight is visible in any pictures. So, in my opinion they used completely new (blank-) barrels for the firing rifles and the flat surfaces at the front (as always: Harry's site) are there to unscrew the barrel.

Cheers,
Stefan


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 7:46 pm 
I love that top picture. So, technically, I can make my shroud so it is one solid piece? That makes my job a lot easier when finishing off my shroud, and would have made bapty's job a lot easier. I like this thread a lot. Keep it going!

One more thing to throw out there: most shrouds (SD, GEM) have special little contours in the shroud edge for the fire selectors, etc on the Thompson gripframe. It the thompson was to slide out, there would have to be no such contours. I figure that bapty didn't have to worry about that due to the pact that they were using thin alluminum rather than thicker resin. What would be done about that?


Brian
Edited by: [url=http://pub217.ezboard.com/bthealienslegacy.showUserPublicProfile?gid=ignaut>Ignaut[/url] at: 12/5/03 12:50 pm


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 8:04 pm 
I don't know, it seems like it would be pretty hard to create a pusle rifle that was sturdy and could be dismantled without taking the shrouds apart. How is the grenade launcher assembly held in place to the thompson? I can't think of a way to get at whatever attachment point would be there wihout taking the shroud halves apart. I agree though it would be nice, right now mine is like taking apart a jigsaw puzzle too.
fdoveraker@att.net


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 8:29 pm 
If Bug Stomper’s PR is one thing, then it is most definitely very solid :D



<span style="color:black;font-family:FederationBold;font-size:medium;]Adapt-Overcome-Survive


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 8:33 pm 
what`s the next step after "very solid" ? very much solid ?




just do it !


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 8:35 pm 
... and it didn't even had the new barrel vent and stock back then :D

Cheers,
Stefan


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 8:42 pm 
Ah ok. Well I'm working with an airsoft Thompson. Mine is attached the same way. Spacer tube but the foregrip frame is made as one piece along with the barrel so that's why I can get at mine without taking the shroud apart.
Image
Image
fdoveraker@att.net


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Fri Dec 05, 2003 10:48 pm 
The following page on Harry's site should answer your question:
www.encom.demon.co.uk/opr15.htm

Cheers,
Stefan


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Sat Dec 06, 2003 5:18 am 
If DEAN O and Bug Stomper are right about both the TM Thomspon and real-steel Thompsons being able to be taken out of the shrouds w/o disassembly to the two halves -- then for the sake of structural strength I suppose I could have the fiberglass shrouds made as a one piece shroud.

BUT -- even though this may be most practical strength-wise, I'm still intending on having my finished shrouds done in left/right halves and figure out the best fastening system later (which now may be using rivets over hex screws).

:)
"We few, we happy few, we band of brothers...For he today that sheds his blood with me
shall be my brother."Edited by: [url=http://pub217.ezboard.com/bthealienslegacy.showUserPublicProfile?gid=menatarms>MENATARMS[/url] at: 12/5/03 10:21 pm


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Sat Dec 06, 2003 6:04 am 
Well, I don't want to jump ahead of myself; I need to get these done--- but the fiberglass shrouds we're working on are just a prelude to what I'm really looking forwards to. There are a certain type of local craftsmen in-country that weld sheet stainless steel (0.7 to 1.0mm) for commercial purposes. They work that sheet stainless steel into all kinds of curves and angles with amazingly clean welds. But nevermind trying explain to them what is a shroud -- just hand the fiberglass ones to them and say here, copy this ...
"We few, we happy few, we band of brothers...For he today that sheds his blood with me
shall be my brother."Edited by: [url=http://pub217.ezboard.com/bthealienslegacy.showUserPublicProfile?gid=menatarms>MENATARMS[/url] at: 12/6/03 11:19 pm


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 Post subject: Re: Q - About Detail on Pulse Rifle Shrouds
PostPosted: Sat Dec 06, 2003 7:46 am 
I'm still waiting to see if someone with more money than good sense will actually CNC a set of shrouds from billet...:lol:

<M>


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