- Location
- Surrey, B.C.
Those pictures brought a tear to my eye.
Aluminum AR180B lower. *Update DONE!*
- Thread starter Armedsask
- Start date
Armedsask,
You don't have to stop to take the chips out.
Next time you can consider an end mill with only 2 flutes.
That will take chips out much better.
Next time you machine a trigger pocket, use MUCH more coolant,
like 5-6 times the volume of the stream in your pic
(use shields so you don't get soacked).
And do not go through with the trigger hole until
after you finished the pocket (exactly like you did).
That will create a "bath tub" which will contain a lot of coolant
under turbulence and the chips will be taken out much easier.
The end mill with 2 flutes will take care of that.
Remember, during CNC machining, usualy there's nobody
to interupt the cycle and clear the chips.
My 2 biggest concerns at the machining of the trigger pockets
are tool vibration and deflection.
I use end mills with very slow twists.
That and a slightly higher rpm gives me the least deflection.
However, vibration might be a problem
and I don't mean the noise (use ear-muffs!).
What I mean is chattering of the cutter which creates
nasty machining marks and dulling of the tool.
Changing just a little the rpm or the feed might help you to find
a "sweet spot" for the tool and stop vibrating.
Needless to say, a very rigid machine is important.
You did good, I hope it measures ok.
You don't have to stop to take the chips out.
Next time you can consider an end mill with only 2 flutes.
That will take chips out much better.
Next time you machine a trigger pocket, use MUCH more coolant,
like 5-6 times the volume of the stream in your pic
(use shields so you don't get soacked).
And do not go through with the trigger hole until
after you finished the pocket (exactly like you did).
That will create a "bath tub" which will contain a lot of coolant
under turbulence and the chips will be taken out much easier.
The end mill with 2 flutes will take care of that.
Remember, during CNC machining, usualy there's nobody
to interupt the cycle and clear the chips.
My 2 biggest concerns at the machining of the trigger pockets
are tool vibration and deflection.
I use end mills with very slow twists.
That and a slightly higher rpm gives me the least deflection.
However, vibration might be a problem
and I don't mean the noise (use ear-muffs!).
What I mean is chattering of the cutter which creates
nasty machining marks and dulling of the tool.
Changing just a little the rpm or the feed might help you to find
a "sweet spot" for the tool and stop vibrating.
Needless to say, a very rigid machine is important.
You did good, I hope it measures ok.
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I'm still deciding what I'm going to make.
I like the way Magpul did the extruded aluminum monolithic upper on their Masada. Might try something like that. How much just custom extruding cost?
I'm leaning towards a long stroke AK style gas system as the bigest problem with my AR180B is getting the gas piston off for cleaning. The RIS covers it and you have to remove the gasblock and slide everything out the front.
I've got a few ideas bouncing around in this head of mine.
I like the way Magpul did the extruded aluminum monolithic upper on their Masada. Might try something like that. How much just custom extruding cost?
I'm leaning towards a long stroke AK style gas system as the bigest problem with my AR180B is getting the gas piston off for cleaning. The RIS covers it and you have to remove the gasblock and slide everything out the front.
I've got a few ideas bouncing around in this head of mine.
A lot of people would flame me for this:
The more I look at that Type 97 Norincho, the more I like it.
I like everything on it, including the gas system.
That would be my first choice.
Well, on that 97 I dont like the trigger, but that's because
it's a makeshift, it's a trigger to replace the original
for the civilian market. The original is a trigger with 4 position selector.
Spend some time and look around.
But I wouldn't go with that stupid Magpul system.
You need an un-compromised positive tightening of the barrel.
I can't do extrusions. Neither can Dlask. Sorry.
I'd say for the beginning,
don't change too many things from the original design.
To switch from stamped sheet metal to carved alum
is enough change for the beginning.
Later you can change the design easy.
The more I look at that Type 97 Norincho, the more I like it.
I like everything on it, including the gas system.
That would be my first choice.
Well, on that 97 I dont like the trigger, but that's because
it's a makeshift, it's a trigger to replace the original
for the civilian market. The original is a trigger with 4 position selector.
Spend some time and look around.
But I wouldn't go with that stupid Magpul system.
You need an un-compromised positive tightening of the barrel.
I can't do extrusions. Neither can Dlask. Sorry.
I'd say for the beginning,
don't change too many things from the original design.
To switch from stamped sheet metal to carved alum
is enough change for the beginning.
Later you can change the design easy.
Oooooh... design suggestion.
Reverse the angle-cut for the magazine well - make it AR15 style, not AR180 style.
When I owned an AR180B I always wondered why they did that. Anyway, your project has me wanting to contact Dlask and see how much they'd charge me to make an aluminum AR180B lower
Good job!
Reverse the angle-cut for the magazine well - make it AR15 style, not AR180 style.
When I owned an AR180B I always wondered why they did that. Anyway, your project has me wanting to contact Dlask and see how much they'd charge me to make an aluminum AR180B lower
Good job!
Minor Hijack -
How are AR180B barrels fitted to the Receiver? Are they just screwed in tight?? I don't recall - but I was wondering if it would it be possible to have the material on the AR15 barrel around the chamber threaded to fit an AR180B upper?
How are AR180B barrels fitted to the Receiver? Are they just screwed in tight?? I don't recall - but I was wondering if it would it be possible to have the material on the AR15 barrel around the chamber threaded to fit an AR180B upper?
That's how it will be.G37 said:
It's because the AR18 was built like that. It was built as a bent sheet metal lower and that was the geometry of the bend and such.
As for my upper, the details aren't finished yet but it will be left side cocking and take standard AR15 barrels. I still haven't decided on a short of long stroke gas system.
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AWESOME job so far!!!!!!
Let me just touch on this:
Keep in mind a Manufacturing Licence is required to legally manufacture recievers for sale or anything other then personal use.
Armedsask has stated that he will not be manufacturing these lowers for sale.Let's leave the issue at that.
So while this is a pretty damn cool project Armedsask has going, any more talk or posts regarding "aquiring" one of these recievers will not be allowed.
Thx.
SKBY.
Let me just touch on this:
Quote:
Originally Posted by Armedsask
I have no plans to make and sell these billet lowers in the near future, stop asking.
What do you mean? Not even for me?
Please, please, pretty please (with sugar on top). Pleeeeeeeeease
Keep in mind a Manufacturing Licence is required to legally manufacture recievers for sale or anything other then personal use.
Armedsask has stated that he will not be manufacturing these lowers for sale.Let's leave the issue at that.
So while this is a pretty damn cool project Armedsask has going, any more talk or posts regarding "aquiring" one of these recievers will not be allowed.
Thx.
SKBY.
P0WERWAGON
CGN Ultra frequent flyer
- Location
- burnaby BC كافر
looking good!!
I guess I'll give you boys a bit of a teaser.
The upper I'm building will be modular. So one basic upper design will be capable of making 4 different rifles.
These will be a pump-action upper in standard configuration, a pump-action upper in bullpup configuration, a semi-auto in standard configuration, and a semi-auto in bullpup configuration.
The differences between the 4 different rifles will be such that you can not change the rifle lay out by simply swapping parts. Each upper assembly is specifically designed for it configuration.
There is the potential for limited manufacture and distribution.
The upper I'm building will be modular. So one basic upper design will be capable of making 4 different rifles.
These will be a pump-action upper in standard configuration, a pump-action upper in bullpup configuration, a semi-auto in standard configuration, and a semi-auto in bullpup configuration.
The differences between the 4 different rifles will be such that you can not change the rifle lay out by simply swapping parts. Each upper assembly is specifically designed for it configuration.
There is the potential for limited manufacture and distribution.
