One thing I notice about 80% lower milling is nobody ever mentions how much metal gets blown all over the place. And fine particles that hang in the air.
Are you using a router jig or drill press jig. Almost all videos i seen using the router option run a vacuum to reduce that issue, A router running at 25k rpm and above is going to make some debris fly. Are you using plenty of cutting fluid to reduce this? Metal everywhere is normal result of drilling or milling anything. As for the particles in air its always good to have PPE eye and face protection.
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Thanks, I think I’m getting there. Well, I’m experimenting clamping the vice inside a gallon freezer bag and holding the router tight with the top intake outside the bag, opening for WD40 shots, but the router over inflates the bag so I connect a shop vac into the bag to pull out the router flow. It needs to have partial outside draw for adjustment so the bag doesn’t completely deflate, so I’m going to insert a pvc Tee between the shop vac and freezer bag to regulate the vacuum. It’s keeping the metal flakes contained.
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Wd40 makes best finish but I think I read it’s not heavy enough to grab and drop the aluminum. I would be doing it outside or close to a door with a fan on pushing it out. Goodluck
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WD40 isn’t what you need. You need some type of oil preferably cutting oil to cut down on heat and to hold the metal particles. WD40 isn’t thick enough to stick and hold the particles of metal when cutting or milling thicker metals. Really any type of oil will work. Many times I use 3in1 oil or whatever I have handy.
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OK, thanks, that’s what I’ll do.
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I didn’t mention it but it would also help to keep your rpm down on whatever tool that you are using. It helps prolong the life of your cutting bit or drill bit. It also keeps from overheating the metal that you are cutting. Cutting T7075 aluminum you shouldn’t get as much heat as cutting steel. Also lower rpm will help the oil trap the metal particles. The oil cuts down on the heat helping to keep the metal and bit cool. With the lower rpm and oil your bit stays sharper longer so it doesn’t take as long as you would think to cut the metal.
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Yeah, my router is unfortunately single speed, but with the setup I have I do frequent pauses to do clean up and checks on the cuts, and let the bit cool. It’s a project.
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I have a drill press that has variable speeds. It would seem to be a good bit harder to do it with a router. With a full speed router the oil won’t work as well because the high speed will most probably throw the oil as well as the metal particles. It will still help though. Good luck, show us some pics of your finished product.
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I have one aluminum 80% lower almost done - yup, metal everywhere, AND the small vaccuum I used to use to clean the car out with is now dead. I ended up doing a couple polymer 80% lowers - which I absolutely love! They come in different colors, the two I have fired are grey - they also have black, green, sand, white, pink, zombie glow in the dark too!
I might get back to finising the aluminum one, but the polymer ones fit so nice and snug with no rattle at all.
If I do the aluminum - I’ll build a box around my drill press first - might even put some plexiglass on the front with holes cut for my hands to enter - (is that going overboard?
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Personally I would try using a heavy cardboard box and a shop vac positioned were most of your debris are coming from. A sheet of plexiglass isn’t really expensive so that wouldn’t hurt either. If you have an extra set of hands holding the shop vac hose and dripping oil for you it should make it easier for you. You could also cut a hole in the cardboard and push the hose through to a position that you need the suction to be.
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I completely rigged my drill press in the most redneck ways possible but can’t argue with success. Zip-tied the shop vac house to a c-clamp on the table to hold it in place. Next I built an oil dripper out of a water bottle and some small gauge tubing with an alligator clip for flow control. If you step your cuts down instead of just trying to plunge full depth from the start you’ll save yourself from excessive to wear and heat (not to mention more manageable chip generation).
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Is it really worth the 8 hours work to mill an 80% lower that costs anywhere from $60 to $130, when you can buy one finished for $100? Yes, it will have a serial number and you will have to go through an FFL, but so what. I’d rather spend my time at the range. 
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I suggest everyone use 80% lowers - and purchase a supply of uppers now, before they get S/N. For the purpose of the 2A, it’s important that the king doesn’t know what swords the peasants own.
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That is good advice. Just like the ammo situation though many of us has seen the writing on the wall for decades. You don’t need to buy a bunch of stuff at these exorbitant prices if you already have what you need put away. The lesson here is to not wait until you think need something. Plan ahead and purchase the items that you need in your own time and when they are on sale. This is one reason that I like PSA so much. They are always running daily deals and sales on every holiday weekend.
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Do you really think the ATF couldn’t raid a vendor of 80% lowers and seize records of buyers? Serial number or not, they would have your address and the quantity you bought.
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If you didn’t already know the ATF raided Polymer 80 and seized all their records. Polymer 80 hasn’t done anything illegal. A push from the Biden administration before they were even in office prompted the ATF to do the illegal raid. The ATF was ordered to return all of Polymer 80’s records because they couldn’t prove that any laws had been broken. Well the ATF gave back the records. You would have to be a complete freaking moron if you don’t think that the first thing that the ATF did was to make copies of Polymer 80’s hard drives. The ATF’s mission was accomplished. They got the records that they couldn’t subpoena legally. These liberal judges that are legislating from the bench have to go. What these “judges” are doing goes against everything that this Country was founded on. It also undermines the separation of powers that is another one of the principles that our government is founded on.
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I would like to try finishing out one of the 80% lowers but I don’t have a router. Will a drill do the job?
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A hand drill wouldn’t work, but others mentioned using a drill press. There’s various contours required and it’s not one width all the way in, so there’s the jigs to guide where to remove material and how deep to go.
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Thanks for the reply.