After drag racing for all of the 70s and most of the 80s culminating in a AA/BAD (later changed to AA/DA and finally to TAD, supercharged alcohol dragster) and a couple of years building custom Harleys, I am very familiar with billet aluminum and it's properties.
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80% AR build/build party in Nahsua, NH --LAST CALL--
- Thread starter Golddiggie
- Start date
After drag racing for all of the 70s and most of the 80s culminating in a AA/BAD (later changed to AA/DA and finally to TAD, supercharged alcohol dragster) and a couple of years building custom Harleys, I am very familiar with billet aluminum and it's properties.
Golddiggie
NES Member
Needed to make some stop nuts for my drill press yesterday (used some ~1" OD brass hex bar) so that we can set the depth stop on it. I'm about to order up some anti-fatigue mats to go onto the concrete floor of the basement in front of the tools. I should have enough for three tool stations with the set I have in my Amazon cart. If people want to bring additional ones for other tools coming over, feel free.
I thought billet only referred to the shape of the raw chunk of metal or whatever you were to machine. We have used billet alum,brass,and polymers. I think it comes from old english. Has to do with the shape of a house or something. Billet has no reflection on the strength properties of the part other then it was machined from a whole. Other options are forging and casting parts out of the same alloy your billet was. Some things are stronger machined this way, others billet may not be the strongest option. I think the term billet became a buzz word when guys started machining their own bike wheels and controls during the big bike build rush a few years back.
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Golddiggie
NES Member
Done right, cast can be just as good as machined from a solid chunk. You can often get tighter tolerances when the entire item is machined from a solid block. But, properly made castings, or forgings, can be just as good. Parts of the lower will be machined either way, where it's more important. If I can ever get my hands on a CNC mill, I'm going to try my hand at making a lower from raw bar stock.
I have placed the order for the anti-fatigue mats already, which should be here on Thursday. Got six 2'x2' squares coming (they can interlock to make larger solid mats). I also have some tubes of diamond compound coming in case someone wants to work on their FCG parts. I'm thinking of cutting some sections of some O1 steel I have (from long ago) to use the with the compounds (as a surface to rub against). I also have some leather we could use with them, if it turns out that is better. I intend to test the compound out on the FCG in my AR pistol before the end of the weekend. That way I'll know if it will work well or not. Or work out any kinks.
After this weekend, we'll just be waiting for the jigs and lowers to show up.
I have placed the order for the anti-fatigue mats already, which should be here on Thursday. Got six 2'x2' squares coming (they can interlock to make larger solid mats). I also have some tubes of diamond compound coming in case someone wants to work on their FCG parts. I'm thinking of cutting some sections of some O1 steel I have (from long ago) to use the with the compounds (as a surface to rub against). I also have some leather we could use with them, if it turns out that is better. I intend to test the compound out on the FCG in my AR pistol before the end of the weekend. That way I'll know if it will work well or not. Or work out any kinks.
After this weekend, we'll just be waiting for the jigs and lowers to show up.
Golddiggie
NES Member
I've always been in the camp of "anything worth doing is worth doing right" and "do it right or don't bother doing it at all"...
I'll probably have a couple of additional squib rods to show people that attend the build party. I'm getting better at making them with each one.
![[smile]](/xen/styles/default/xenforo/smilies.vb/001.gif "Smile [smile]")
Castings will never be as strong as forged and forged, generally speaking, is not as strong as billet. It all has to do with the grain of the material.
Cast is no where near as strong as the other two, the grain is a total mishmash and it can also have air pockets in the casting. Casting is nothing more than pouring melted aluminum into a mold.
With a forging it is hammered into shape which does not mess with the grain of the material as much. Billet is capable of being even stronger depending on the application and alloy used. The grain is not messed with at all, but it requires much more machining.
Golddiggie
NES Member
When done properly, you won't have any pockets/voids in a cast item.
I just did some checking. The AA 80% lowers we're getting are forged.
"These 80 Percent AR-15 Lower receivers start as 7075-T6 forgings from the lead forge in the US and are fully machined to mil-spec tolerances."
So chances are, you'll find either forged or billet receiver hardware out there.
AA's are absolutely forged, I wouldn't have ordered one if they weren't. I don't think anybody even offers a cast receiver anymore. They used to be available, the Olympic plinker model was based on a cast receiver. That's the only complete rifle based on a cast receiver that I know of and it was discontinued long ago. They had problems with the pivot pin boss breaking off.
I said it can happen, which it can, not that it would absolutely happen. The air pockets are the least of your concern with castings, the major ones being the disruption of the grain and the silicones and crap that they have to add to the alloy to get the molten aluminum to flow into the mold. They weaken the alloy.
lancecolonel
NES Member
love the cast vs forged vs billet info, good stuff. (seriously-i didn't know this before and it's good info to have)
now for the really important stuff, do we have a tentative date for this party? golddiggie, any particular dates you are looking at? inquiring minds want to know. thanks.
now for the really important stuff, do we have a tentative date for this party? golddiggie, any particular dates you are looking at? inquiring minds want to know. thanks.
Golddiggie
NES Member
Pretty much... Got the weekend of the 23rd penciled in so far. Just comes down to when we get the lowers in hand (and associated jigs).
Sooo, I might be wrong but I thought all metal starts its journey to us as a bubbly molton liquid of future evil goodness in a large ladle at a foundry.
That liquid is poured into casts to make billets or blanks. Does that make the metal you machine the lower out of ( some call that a billet) a casting? When you forge something you are smashing the grain of the metal into a tighter organized pattern. I want a forged lower that is left fat then machined to get that nice "billet" look you get when you machine the whole part. The funny part is that the anodizing is stronger then all of them. Is billet Mill -spec?
That liquid is poured into casts to make billets or blanks. Does that make the metal you machine the lower out of ( some call that a billet) a casting? When you forge something you are smashing the grain of the metal into a tighter organized pattern. I want a forged lower that is left fat then machined to get that nice "billet" look you get when you machine the whole part. The funny part is that the anodizing is stronger then all of them. Is billet Mill -spec?
Golddiggie
NES Member
I know they have to pour the metal into either bar, billet, or ingot form initially. At least in order to create the alloy. I've not done any deep diving into what happens at a microscopic level between the processes. I do know that forging doesn't do much to the grain structure until you heat treat and temper (at least for steel). Sure, it can do things to the grain orientation, but we're not talking about drastic changes here.
When I was making knives, I would work with bar stock, since I didn't have a forge. I wasted more material than if I did have a forge this way.
For the firearm parts, I'm pretty sure what most people think of for forging processes doesn't match. They heat the metal up to the point where it can be shaped safely (without breaking) and then use large hammers with the patterns on either side. A whack (or a few) in the 'hammer' set is all it takes to make the shape.
On another note, the diamond paste I ordered arrived today. I cut a piece of O1 tool steel to use with it, as well as a section of leather. After testing both base materials, I think I like the leather better. It seems to give a more polished finish faster than using the steel as a base for the paste. I used the three compounds (6 micron, 3 micron and 1 micron) on the trigger and hammer in my AR pistol build/lower. Took even more of the grit out of the FCG that way. I think the only way I'll be able to improve the trigger, now, is to replace the springs and/or use a set screw to remove some of the travel before it breaks. Not sure if I want to go with the screw in the pistol.
When I was making knives, I would work with bar stock, since I didn't have a forge. I wasted more material than if I did have a forge this way.
For the firearm parts, I'm pretty sure what most people think of for forging processes doesn't match. They heat the metal up to the point where it can be shaped safely (without breaking) and then use large hammers with the patterns on either side. A whack (or a few) in the 'hammer' set is all it takes to make the shape.
On another note, the diamond paste I ordered arrived today. I cut a piece of O1 tool steel to use with it, as well as a section of leather. After testing both base materials, I think I like the leather better. It seems to give a more polished finish faster than using the steel as a base for the paste. I used the three compounds (6 micron, 3 micron and 1 micron) on the trigger and hammer in my AR pistol build/lower. Took even more of the grit out of the FCG that way. I think the only way I'll be able to improve the trigger, now, is to replace the springs and/or use a set screw to remove some of the travel before it breaks. Not sure if I want to go with the screw in the pistol.
Link to the DROs on my Mini Mill Thread.
http://www.northeastshooters.com/vb...ros-mounted-my-mini-mill-pix-per-request.html
Malodave
http://www.northeastshooters.com/vb...ros-mounted-my-mini-mill-pix-per-request.html
Malodave
awesomesauce!
That was the plan from the beginning. I wanted to make a "Z" block to set the depth on the drill press but I need
some dimensions from the Tactical Machining jig to be accurate. I've gotten no response from Ares Armor or
Tactical Machining on the issue.
Malodave
Re: 80% AR build/build party in Nahsua, NH
I had planned on bringing my jig to the build party. I don't know if you want to use the dimensions from mine to make your block. It's not a tm one though.
Sent from my SCH-I535 using Tapatalk 2
I had planned on bringing my jig to the build party. I don't know if you want to use the dimensions from mine to make your block. It's not a tm one though.
Sent from my SCH-I535 using Tapatalk 2
Golddiggie
NES Member
With the stop nuts on the drill press now, we can simply set it to go to the correct depth. I intend to set the table to the correct height to make this easier too. Probably going to use the 2 way travel vise to hold the jig and lower for the press. We have the drawings for AR15 (and AR10) lowers, so we should be ok in getting the drill, and mill, depths correct. I do hope that the jigs come with some good instruction sheets though, to make things easier on us.
Also looks like we'll be getting the mill in place either this weekend or sometime next week.
I'm also getting ready to keg another batch of beer either today, or over the weekend. Just need 1-2 weeks for it to be carbonated and then it will be on tap.
Also looks like we'll be getting the mill in place either this weekend or sometime next week.
I'm also getting ready to keg another batch of beer either today, or over the weekend. Just need 1-2 weeks for it to be carbonated and then it will be on tap.
Golddiggie
NES Member
Holes from the sides are through, the FCG cavity will be hogged out via drill first, then finished with the mill (making it much better).
The depth is not all that critical on the FCG pocket. Just don't punch through the bottom![[shocked]](/xen/styles/default/xenforo/smilies.vb/007.gif "Shocked [shocked]")
If you have an assembled lower - take a look in there.
Getting the width is right is more important.
If you have an assembled lower - take a look in there.Getting the width is right is more important.
I'm so in .. I just don't have anything to add. You two have gone way further than I thought we were going to go.
I was going to hog mine out in my garage usuing fred flinstone tools. I am very grateful and excited to meet and work with you guys. I am sure I will learn a lot. The prospect of Great beer is even more exciting!
I was going to hog mine out in my garage usuing fred flinstone tools. I am very grateful and excited to meet and work with you guys. I am sure I will learn a lot. The prospect of Great beer is even more exciting!
I haven't really been present in the build party threads but I wanted to let you all know that Golddiggies Nahsua party will be the first to be supplied. I feel safe in saying that we could do this as early as the 6th or 7th if everyone is available.
