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AR lower...notice anything different...

RugerNinerRugerNiner Member Posts: 12,636 ✭✭✭
edited August 2009 in General Discussion
about this lower?

ARLOWER-MACH-D.jpg
spn05j5e04xq.gif


Keep your Powder dry and your Musket well oiled.
NRA Lifetime Benefactor Member.

Comments

  • bama55bama55 Member Posts: 6,389 ✭✭
    edited November -1
    Solid trigger guard.
  • matwormatwor Member Posts: 20,594
    edited November -1
    It doesn't say fire or safe by the lower large hole?
  • reloader44magreloader44mag Member Posts: 19,356 ✭✭
    edited November -1
    machine work on external looks like sheet?
  • matwormatwor Member Posts: 20,594
    edited November -1
    Dang bama, you're right!!! At least it was a fellow brother that got it right.

    BTW, I still haven't made it to Waco yet, but when I do I owe ya an e-mail.
  • bamafanbamafan Member Posts: 4,011 ✭✭
    edited November -1
    quote:Originally posted by matwor
    Dang bama, you're right!!! At least it was a fellow brother that got it right.

    BTW, I still haven't made it to Waco yet, but when I do I owe ya an e-mail.



    That wasn't me. [:D][:D]
  • cwi555cwi555 Member Posts: 1,132 ✭✭✭✭✭
    edited November -1
    quote:Originally posted by RugerNiner
    about this lower?

    ARLOWER-MACH-D.jpg


    Thats a nice looking receiver. I've got some archaic test data on AR/M16 lowers from the 60's I'm trying to find. I recall it saying there was a reason why that particular area was left open.
    If my memory hasn't failed me, I recall there being a concern with fatigue cracking due to alternating compressional/tensile stresses (cyclic stress) set up by the cycling of the action, and vibration due to the same.

    If I find it I'll post it up here. If I can't find it, I'll order one myself and reproduce the test then post.
    check back on this topic in a couple of weeks.

    It would be nice if that were not the case though. Those roll pins for that guard are a pain, not to mention the tabs being in a position that are easy to break off during installation.
  • matwormatwor Member Posts: 20,594
    edited November -1
    quote:Originally posted by bamafan
    quote:Originally posted by matwor
    Dang bama, you're right!!! At least it was a fellow brother that got it right.

    BTW, I still haven't made it to Waco yet, but when I do I owe ya an e-mail.



    That wasn't me. [:D][:D]


    Whoa!! That was weird!!![;)][:D][:I][:I]
  • givettegivette Member Posts: 10,886
    edited November -1
    Also, the "fencing" around the top edge, and the mag release is not rounded, as in production guns. Is this an 80pct receiver?
  • cwi555cwi555 Member Posts: 1,132 ✭✭✭✭✭
    edited November -1
    quote:Originally posted by givette
    Also, the "fencing" around the top edge, and the mag release is not rounded, as in production guns. Is this an 80pct receiver?


    Noticed that one as well. Normally those areas receive a minimal radius to alleviate stress risers.

    Think I'll be ordering one to test. I've got mountains of tech data still not organized from my last move, so gave up the box search.
    I believe I am going to have to bite the bullet and get it all scanned in electronically.
  • shoff14shoff14 Member Posts: 11,994 ✭✭✭
    edited November -1
    So whats so fancy about it? Standard completely machined from solid aluminum receiver. Plenty of them on the market.

    It would be nice if the trigger guard was lower then it is. If someone is machining them, there is no reason to have the straight trigger guard you install on most lowers.


    This also could possibly be a composite lower, but to hard to tell from the picture.
  • nemesisenforcernemesisenforcer Member Posts: 10,513 ✭✭✭
    edited November -1
    It's not made out of tinfoil and pita bread like mine is?
  • cwi555cwi555 Member Posts: 1,132 ✭✭✭✭✭
    edited November -1
    quote:Originally posted by shoff14
    So whats so fancy about it? Standard completely machined from solid aluminum receiver. Plenty of them on the market.

    It would be nice if the trigger guard was lower then it is. If someone is machining them, there is no reason to have the straight trigger guard you install on most lowers.


    It's cheap is the main thing. Listing at 109.00.
    The literature made no mention of T6 hardening either.
    Cost of the billet would be around 20 bucks, automated machining cost probably around 15 bucks per unit, procurement, shipping, maintenance of equipment, etc etc should be around another 10-20 per unit. Heat treating should be 10 per unit.

    I estimate the factory has 55-75 dollars per unit in it.
    Nobody is making a killing on that, thats for sure.
    If your gas gets to weak (<6%) on T6 hardening, it will give it a very shallow surface hardness.

    All in all, it will be interesting to see the results of a good test.
  • shoff14shoff14 Member Posts: 11,994 ✭✭✭
    edited November -1
    quote:Originally posted by cwi555
    quote:Originally posted by shoff14
    So whats so fancy about it? Standard completely machined from solid aluminum receiver. Plenty of them on the market.

    It would be nice if the trigger guard was lower then it is. If someone is machining them, there is no reason to have the straight trigger guard you install on most lowers.


    It's cheap is the main thing. Listing at 109.00.
    The literature made no mention of T6 hardening either.
    Cost of the billet would be around 20 bucks, automated machining cost probably around 15 bucks per unit, procurement, shipping, maintenance of equipment, etc etc should be around another 10-20 per unit. Heat treating should be 10 per unit.

    I estimate the factory has 55-75 dollars per unit in it.
    Nobody is making a killing on that, thats for sure.
    If your gas gets to weak (<6%) on T6 hardening, it will give it a very shallow surface hardness.

    All in all, it will be interesting to see the results of a good test.


    If that piece of aluminum cost $20, every machine shop in America would be out of business. I am not up on the current prices of aluminum, as I do not buy any at my current job. However, it has maintained around 2.00-2.30 a pound for 6061-t6. Buying in large quantities or in sheets, a little cheaper. Looking about about $14 in material. The good lowers are made of 7075, which is harder to machine and more expensive then 6061.

    Aluminum has any tempering or heat treating to the material before machining and it is bought that way. I don't know of any aluminum or aluminum composite that can be heat treated after machining.

    Now, if I was making these, I would cut the profile on a water jet or laser cutting machine out of sheet. Send them to a horizontal machining center. Can probably be done with some fancy set ups in 2 ops. You run tombstones, setting one set of parts up while the machining is running the other tombstone. In fact, I would probably set one tombstone up for the first op, second tombstone on the second op, then I always have finished parts coming off the machine. Once you find your tool failure points, reduce by 5% or 10% and spot check the parts. Your real option to making them is whether you want to broach the magwell, or EDM it. It would probably be faster to rough it out on the mill, and broach it. I would broach it right on the mill, if my set up was rigid enough.

    Total machine time, 10-15 minutes, cheap shops charge $60 an hour. You then have some deburring and shot blasting cost, which is probably done by the anodizer. Anodizing will run about $.50 to a $1.00 on a part that size, in decent quantity for black. Different colors would be a little more, or if you want your part checked to a standard. Shipping would be the most expensive part.

    With all that said, the machine shop needs to be making these in the $30-40 range to be making any profit and allow the dealer to make a profit. Probably looking at $60 wholesale cost for the dealer. Allowing for proper mark up by both the manufacturer and dealer.

    I love when people use the word "billet" in context that isn't correct, cracks me up. [:D]
  • 1911a1-fan1911a1-fan Member Posts: 51,193 ✭✭
    edited November -1
    quote:Originally posted by shoff14
    quote:Originally posted by cwi555
    quote:Originally posted by shoff14
    So whats so fancy about it? Standard completely machined from solid aluminum receiver. Plenty of them on the market.

    It would be nice if the trigger guard was lower then it is. If someone is machining them, there is no reason to have the straight trigger guard you install on most lowers.


    It's cheap is the main thing. Listing at 109.00.
    The literature made no mention of T6 hardening either.
    Cost of the billet would be around 20 bucks, automated machining cost probably around 15 bucks per unit, procurement, shipping, maintenance of equipment, etc etc should be around another 10-20 per unit. Heat treating should be 10 per unit.

    I estimate the factory has 55-75 dollars per unit in it.
    Nobody is making a killing on that, thats for sure.
    If your gas gets to weak (<6%) on T6 hardening, it will give it a very shallow surface hardness.

    All in all, it will be interesting to see the results of a good test.


    If that piece of aluminum cost $20, every machine shop in America would be out of business. I am not up on the current prices of aluminum, as I do not buy any at my current job. However, it has maintained around 2.00-2.30 a pound for 6061-t6. Buying in large quantities or in sheets, a little cheaper. Looking about about $14 in material. The good lowers are made of 7075, which is harder to machine and more expensive then 6061.

    Aluminum has any tempering or heat treating to the material before machining and it is bought that way. I don't know of any aluminum or aluminum composite that can be heat treated after machining.

    Now, if I was making these, I would cut the profile on a water jet or laser cutting machine out of sheet. Send them to a horizontal machining center. Can probably be done with some fancy set ups in 2 ops. You run tombstones, setting one set of parts up while the machining is running the other tombstone. In fact, I would probably set one tombstone up for the first op, second tombstone on the second op, then I always have finished parts coming off the machine. Once you find your tool failure points, reduce by 5% or 10% and spot check the parts. Your real option to making them is whether you want to broach the magwell, or EDM it. It would probably be faster to rough it out on the mill, and broach it. I would broach it right on the mill, if my set up was rigid enough.

    Total machine time, 10-15 minutes, cheap shops charge $60 an hour. You then have some deburring and shot blasting cost, which is probably done by the anodizer. Anodizing will run about $.50 to a $1.00 on a part that size, in decent quantity for black. Different colors would be a little more, or if you want your part checked to a standard. Shipping would be the most expensive part.

    With all that said, the machine shop needs to be making these in the $30-40 range to be making any profit and allow the dealer to make a profit. Probably looking at $60 wholesale cost for the dealer. Allowing for proper mark up by both the manufacturer and dealer.

    I love when people use the word "billet" in context that isn't correct, cracks me up. [:D]


    as the currect exise tax and thats about where we are now
  • bama55bama55 Member Posts: 6,389 ✭✭
    edited November -1
    quote:Originally posted by matwor
    quote:Originally posted by bamafan
    quote:Originally posted by matwor
    Dang bama, you're right!!! At least it was a fellow brother that got it right.

    BTW, I still haven't made it to Waco yet, but when I do I owe ya an e-mail.



    That wasn't me. [:D][:D]


    Whoa!! That was weird!!![;)][:D][:I][:I]


    Matt, I'm the one that still lives in Bama.[:D]
  • cwi555cwi555 Member Posts: 1,132 ✭✭✭✭✭
    edited November -1
    quote:Originally posted by shoff14
    quote:Originally posted by cwi555
    quote:Originally posted by shoff14
    So whats so fancy about it? Standard completely machined from solid aluminum receiver. Plenty of them on the market.

    It would be nice if the trigger guard was lower then it is. If someone is machining them, there is no reason to have the straight trigger guard you install on most lowers.


    It's cheap is the main thing. Listing at 109.00.
    The literature made no mention of T6 hardening either.
    Cost of the billet would be around 20 bucks, automated machining cost probably around 15 bucks per unit, procurement, shipping, maintenance of equipment, etc etc should be around another 10-20 per unit. Heat treating should be 10 per unit.

    I estimate the factory has 55-75 dollars per unit in it.
    Nobody is making a killing on that, that's for sure.
    If your gas gets to weak (<6%) on T6 hardening, it will give it a very shallow surface hardness.

    All in all, it will be interesting to see the results of a good test.


    If that piece of aluminum cost $20, every machine shop in America would be out of business. I am not up on the current prices of aluminum, as I do not buy any at my current job. However, it has maintained around 2.00-2.30 a pound for 6061-t6. Buying in large quantities or in sheets, a little cheaper. Looking about about $14 in material. The good lowers are made of 7075, which is harder to machine and more expensive then 6061.

    Aluminum has any tempering or heat treating to the material before machining and it is bought that way. I don't know of any aluminum or aluminum composite that can be heat treated after machining.

    Now, if I was making these, I would cut the profile on a water jet or laser cutting machine out of sheet. Send them to a horizontal machining center. Can probably be done with some fancy set ups in 2 ops. You run tombstones, setting one set of parts up while the machining is running the other tombstone. In fact, I would probably set one tombstone up for the first op, second tombstone on the second op, then I always have finished parts coming off the machine. Once you find your tool failure points, reduce by 5% or 10% and spot check the parts. Your real option to making them is whether you want to broach the magwell, or EDM it. It would probably be faster to rough it out on the mill, and broach it. I would broach it right on the mill, if my set up was rigid enough.

    Total machine time, 10-15 minutes, cheap shops charge $60 an hour. You then have some deburring and shot blasting cost, which is probably done by the anodizer. Anodizing will run about $.50 to a $1.00 on a part that size, in decent quantity for black. Different colors would be a little more, or if you want your part checked to a standard. Shipping would be the most expensive part.

    With all that said, the machine shop needs to be making these in the $30-40 range to be making any profit and allow the dealer to make a profit. Probably looking at $60 wholesale cost for the dealer. Allowing for proper mark up by both the manufacturer and dealer.

    I love when people use the word "billet" in context that isn't correct, cracks me up. [:D]


    6061-t6.

    T6 is not inherent in 7075. You can get it that way, but it doesn't do you a lot of good in this for instance.
    My terminology is generalized. Most people utilize the term "heat treating" to mean any post solidifation method.

    If you wish to get specific, the term could be hardening/tempering or others depending on your background.

    http://www.liquidcooledairpower.com/lc-topendheat.shtml

    That is from the automotive world. The aerospace world will consider it tempering and thus the T designation.
    Aluminum in general is an austenitic grain structure, and as such is not subject to standard steel hardening techniques (heat treat. Shoot me for trying to get the idea across without specifics)
    You can however temper it to varying degrees.
    You can in fact temper it after the fact. A lot of companies order it pre treated as the cost of treating after the fact is often prohibitive. Either way, your going to pay for it, be it you do it yourself or have alcoa do it for you.
    BTW, when you treat one, it's in solution. Generally speaking, they all require submersion in a liquid before you treat them. That goes for any material that utilizes an austinitic grain structure.

    From alcoa:
    6061
    http://www.alcoa.com/adip/catalog/pdf/Extruded_Alloy_6061.pdf
    7075
    http://www.alcoa.com/mill_products/catalog/pdf/alloy7075techsheet.pdf
    quote:Many heat treatments and heat treating practices are available to develop optimum strength, toughness and other desirable characteristics for proper application of alloy 7075 sheet and plate
    products. Refer to MIL-H-6088, Heat Treatment of Aluminum
    Alloys for additional information

    Speaking of Mil-H-6088, that information is dated. The following is a quote of notice 1.
    "MIL-H-6088G (NOTICE 1), MILITARY SPECIFICATION: HEAT TREATMENT OF ALUMINUM ALLOYS (26 SEP 1997) [S/S BY SAE-AMS-H-6088]., MIL-H-6088G, dated 1 April 1991, along with amendment 1, dated 15 September 1992, is hereby canceled. Future heat treatment should refer to SAE-AMS-H-6088, "Heat Treatment of Aluminum Alloys". (Application for copies of SAE - Aerospace Material Specifications should be addressed to SAE, 400 Commonwealth Drive, Warrendale, PA 15096.)"

    HMMM there's those heat treat words again......

    You will note that even alcoa the largest manufacture of aluminum in the country and one of the largest in the world, utilizes the words "heat treatment".
    So if you have a problem with my usage, you may wish to contact them and let them know that in your considered expertise, they are wrong.
    While your at it, you need to contact the military and let them know they are screwing up to.

    BTW I set the specs in my current job, and have acted as a purchaser in the past, the $20 figure is from Thursday July 30th 2009 prices from our supplier for enough material to make 500 receivers for 7075-0. The figure goes up if you have them perform the T6 process.

    Your comment about EDM or broach is interesting. Electric discharge machining gets expensive. It's typically used for fine detail work I.E. prototypes, coin dies, and other non-high production work.
    Unless there has been a technological breakthrough in the last few years I am unaware of, a company would go broke trying to use it in the manner you suggest.
    Now if you water jet the magazine well, and use the EDM for the fine detail work, that would be plausible.

    BTW, Some receivers are in fact made of 6061. The difference between 6061 and 7075 is in weldability. Good luck getting a sound weld on the 7075 of any temper or grade. You can in fact get a weld on the 6061.

    As for cost, my estimate is assuming they did everything right which is yet to be seen. Your cost will assume they cut several corners.

    At one time I considered going into business manufacturing AR receivers. I did not go with it as it's a cut throat market with very very little margin. My estimates given here were those same numbers from 3 years ago transposed to current market values.

    The taxes were also left out of it.
    http://www.ttb.gov/firearms/reference_guide.shtml
    If you jump down to section V of the link, you'll note an area for calculation of tax.
    It gets really screwy trying to sort this out, but at the end of the day, the tax is hit 10 ways to sunday.
    I don't know what is as of this day, but when I calc'd it 3 years ago it came to 10 bucks per unit.

    All smart comments aside, You will learn I don't post garbage. If it's in my post I can back it up. If I can't back it up, I don't post. It's simple as that. I understand that BS post are rampant on open forums like this, but metals, metallurgy, welding, inspection, QA/QC is what I do for a living and have done so for a very long time now.
    I also understand that there are many misconceptions in the metals and firearms industry. Someone says something and no one corrects them. It gets a life of it's own. Thats how none standard terms get started. It's more the norm than the exception.
    Just as you noted the term "billet" is often misused.
    We can get into the bug dust if you wish, or we can just continue the assumptions and try to understand what the message is rather than the conveyance.
    In all cases, you can bank on the fact I've got reams of documentation backing me before I open my mouth.
  • cwi555cwi555 Member Posts: 1,132 ✭✭✭✭✭
    edited November -1
    quote:Originally posted by RugerNiner
    about this lower?

    ARLOWER-MACH-D.jpg

    1911-
    BTW, I have the original 6088G spec, but there are copyright issues with posting it up.
    You can purchase the current spec for a reasonable price from techstreet, it may be worth your while as it's full of very valuable information.
  • gatorhidegatorhide Member Posts: 562 ✭✭
    edited November -1
    quote:Originally posted by shoff14
    quote:Originally posted by cwi555
    quote:Originally posted by shoff14
    So whats so fancy about it? Standard completely machined from solid aluminum receiver. Plenty of them on the market.

    It would be nice if the trigger guard was lower then it is. If someone is machining them, there is no reason to have the straight trigger guard you install on most lowers.


    It's cheap is the main thing. Listing at 109.00.
    The literature made no mention of T6 hardening either.
    Cost of the billet would be around 20 bucks, automated machining cost probably around 15 bucks per unit, procurement, shipping, maintenance of equipment, etc etc should be around another 10-20 per unit. Heat treating should be 10 per unit.

    I estimate the factory has 55-75 dollars per unit in it.
    Nobody is making a killing on that, thats for sure.
    If your gas gets to weak (<6%) on T6 hardening, it will give it a very shallow surface hardness.

    All in all, it will be interesting to see the results of a good test.


    If that piece of aluminum cost $20, every machine shop in America would be out of business. I am not up on the current prices of aluminum, as I do not buy any at my current job. However, it has maintained around 2.00-2.30 a pound for 6061-t6. Buying in large quantities or in sheets, a little cheaper. Looking about about $14 in material. The good lowers are made of 7075, which is harder to machine and more expensive then 6061.

    Aluminum has any tempering or heat treating to the material before machining and it is bought that way. I don't know of any aluminum or aluminum composite that can be heat treated after machining.

    Now, if I was making these, I would cut the profile on a water jet or laser cutting machine out of sheet. Send them to a horizontal machining center. Can probably be done with some fancy set ups in 2 ops. You run tombstones, setting one set of parts up while the machining is running the other tombstone. In fact, I would probably set one tombstone up for the first op, second tombstone on the second op, then I always have finished parts coming off the machine. Once you find your tool failure points, reduce by 5% or 10% and spot check the parts. Your real option to making them is whether you want to broach the magwell, or EDM it. It would probably be faster to rough it out on the mill, and broach it. I would broach it right on the mill, if my set up was rigid enough.

    Total machine time, 10-15 minutes, cheap shops charge $60 an hour. You then have some deburring and shot blasting cost, which is probably done by the anodizer. Anodizing will run about $.50 to a $1.00 on a part that size, in decent quantity for black. Different colors would be a little more, or if you want your part checked to a standard. Shipping would be the most expensive part.

    With all that said, the machine shop needs to be making these in the $30-40 range to be making any profit and allow the dealer to make a profit. Probably looking at $60 wholesale cost for the dealer. Allowing for proper mark up by both the manufacturer and dealer.

    I love when people use the word "billet" in context that isn't correct, cracks me up. [:D]


    ......You've provided some insightful information here. Thanks for sharing!
  • shoff14shoff14 Member Posts: 11,994 ✭✭✭
    edited November -1
    CWI,

    Not trying to get in a pissing match.

    What I was saying, is there is no way they are making this out of 7075. This is a cost thing, they double their machine time with 7075. Yes there is a big difference in weldabilty, but you don't see anyone welding receivers do you? Didn't think so.

    All BS aside, there isn't any way to get a 6061 part to hold size if you temper it after you machine it. Plus it gets rid of some of the gummyness.

    As far as EDM's, there are several AR lower manufacturers using this method. In front of me I have a RRA lower, with starting serial KT.It has the magwell pocket cut with an EDM. I have another RRA lower, that with serial CM (Continental machine) that was broached. So yes, EDM's are used for production. We used them for production at my last job. Aluminum cuts fairly well on and EDM, with a bigger wire diameter

    Yes, my cost will assume they cut corners. Probably only quality check the holes every 20 or so parts. Check the threads every 50 parts, ect. That is the advantage of 6061, tools last quite a while.

    This statement still stands though
    quote:With all that said, the machine shop needs to be making these in the $30-40 range to be making any profit and allow the dealer to make a profit. Probably looking at $60 wholesale cost for the dealer. Allowing for proper mark up by both the manufacturer and dealer.
  • bigtirebigtire Member Posts: 24,800
    edited November -1
    It's completely machined, not cast. Solid trigger guard. It also looks as if it could be made of steel.
  • vicg1vicg1 Member Posts: 1,033 ✭✭✭✭✭
    edited November -1
    quote:Originally posted by 1911a1fan
    as the currect exise tax and thats about where we are now


    no excise tax on lowers...
  • shoff14shoff14 Member Posts: 11,994 ✭✭✭
    edited November -1
    I happened to run across a picture, just to prove a point.

    IMAG0007.jpg
  • cwi555cwi555 Member Posts: 1,132 ✭✭✭✭✭
    edited November -1
    quote:Originally posted by shoff14
    CWI,

    Not trying to get in a pissing match.

    What I was saying, is there is no way they are making this out of 7075. This is a cost thing, they double their machine time with 7075. Yes there is a big difference in weldabilty, but you don't see anyone welding receivers do you? Didn't think so.

    All BS aside, there isn't any way to get a 6061 part to hold size if you temper it after you machine it. Plus it gets rid of some of the gummyness.

    As far as EDM's, there are several AR lower manufacturers using this method. In front of me I have a RRA lower, with starting serial KT.It has the magwell pocket cut with an EDM. I have another RRA lower, that with serial CM (Continental machine) that was broached. So yes, EDM's are used for production. We used them for production at my last job. Aluminum cuts fairly well on and EDM, with a bigger wire diameter

    Yes, my cost will assume they cut corners. Probably only quality check the holes every 20 or so parts. Check the threads every 50 parts, ect. That is the advantage of 6061, tools last quite a while.

    This statement still stands though
    quote:With all that said, the machine shop needs to be making these in the $30-40 range to be making any profit and allow the dealer to make a profit. Probably looking at $60 wholesale cost for the dealer. Allowing for proper mark up by both the manufacturer and dealer.


    We will have to agree to disagree on that "standing statement". My cost analysis for manufacturing them does not align with that statement.

    They are killing themselves using EDM for the hogging out the mag well. A water jet will do the gross work, then finish with EDM.

    As for 7075 they can be machined a lot easier in the T-0 form.
    You can in fact treat them after the fact via a nitride solution but the holes will have to be finalized after the fact.

    There are a lot of ways to skin the cat, but I'll have firm data once I cut the receiver I have incoming. I'll know exactly what they did then. I am being told there is a 6 week backorder from my dealer, so be sure to check back on this topic then.
  • shoff14shoff14 Member Posts: 11,994 ✭✭✭
    edited November -1
    quote:Originally posted by cwi555



    They are killing themselves using EDM for the hogging out the mag well. A water jet will do the gross work, then finish with EDM.

    Why would you rough it out? It doesn't need to be roughed out if your going to use an EDM. An EDM doesn't care how much material is in the center, its going to run the wire around the profile of the magwell. Drill a .25" hole close to the edge and be done with it. Set a fixture up, program the machine to start at the holes, let the machine do its job while the operator is doing something else. That is the main advantage of an EDM, yes it takes a little time, but you can have one person running 3, 4 or even 5 machines. I would still broach them though. I can agree with you on that.

    As for 7075 they can be machined a lot easier in the T-0 form.
    You can in fact treat them after the fact via a nitride solution but the holes will have to be finalized after the fact.

    My point exactly. If they are hardened/tempered, whatever you want to call it after they are machined, they will need another op to machine them because you can't hold .0005" tolerance after they are tempered. That is the tolerance we are talking about for those pins. Makes a hell of a lot more sense to make them out of already tempered material. Yes, T-0 would be nice to use and cuts well, but its not ideal to need another op just for the holes.
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