Aluminum AR180B lower. *Update DONE!*

yeah - with that rifle it FEELs like its just a matter of time before breaks, apparently it is very strong...

I am not a metallurgist/machinist but why not cast it? a cast must be stronger than that plastic? - not as nice but... thos whole deal is to strenthen that hinge point right?

f7
 
Casting is expensive for minimum production. I'd have to spend all the money making the molds and then still do machining. With the capabilities of CNC machines these days, it's taking over a lot of stuff that used to be cast.

As it sits my cost is zero now that I've bought the material. All that remains is to put in the time.
 
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Casting would be desirable if you were making a number of copies and you want to cut down on material and machining costs. The problem is that you have a lot of up front design costs for the patterns. Also a casting will need to be heat treated. If it can be produced on a cnc machine it would be less work.
 
Rudy H said:
Casting would be desirable if you were making a number of copies and you want to cut down on material and machining costs. The problem is that you have a lot of up front design costs for the patterns. Also a casting will need to be heat treated. If it can be produced on a cnc machine it would be less work.
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Cast aluminum doesnt need heat treat. Just anoidize for hardness. Even if it was steel it still wouldnt need heat treat unless it was an upper your speaking of.
 
But the point is moot as I have no intention of casting anything.

I still think that with the capabilities of CNC, no casting should ever be needed.
 
I was finally able to get some free shop time and start cutting some material off. All I can say is damn I love cutting aluminum! It's like butter and the carbide leaves such a gorgeous surface finish.

Any way, front end has been faced to length in relation to the mag well. Side profiles have been cut so the block is the proper width. Front pivot pin slot is cut. Also, I've manage to screw up already. :redfaced:

billet_screwup.jpg

Nothing serious, mostly cosmetic. That'll teach me for getting in a rush. All I want is a full day to work on this thing and I'd be able to finish most of it.

My blueprints are essentially finished, I'm still tweaking them and making minor changes, mostly to the format. After all the work I've put in them there is a pretty good chance I'll offer the plans for sale ones I finish my lower and know it works.
 
Ok how much would you charge us armedsask for a metal receiver?

By the way I wanted to ask you where did you get the forend & vertical grips, your stock, cheek rest, rails and site?????? I would like to build some thing like that. Could you PM with the details and costs, please. I really like your setup.
 
Armedsask, if that's the billet that I know about,
remember the material is 7475 T7.
Think of another way to fix it, because it's practically unweldable with regular procedures.
 
Dr.Lector said:
Armedsask, if that's the billet that I know about,
remember the material is 7475 T7.
Think of another way to fix it, because it's practically unweldable with regular procedures.
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Hmm, here I thought it was 7075 T6.

I have no intention of welding or fixing the mistake. It's minor and cosmetic. The most I'll do, if I do anything, is fill it up with some type of filler just to make it look good but that's not to high on the list. I've learned my lesson to slow down and not rush things. Easier said than done when you've got other people needing to use a machine.

Edit: I have no plans to make and sell these billet lowers in the near future, stop asking.
 
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