View Full Version : 80% Arms- Easy Jig
Picked up an "Easy Jig" from 80% Arms. Man this thing makes it simple. It's definitely one of the pricier jigs out there, but it's worth it in my opinion. You use a router to do the bulk of the work with a mill bit so you dont tear up your drill press spindle bearings. The jig has marked depth gauges so you can leave your calipers in your toolbox.
The jig only works with their lowers, but you can take a dremel to the side plates to fit other lowers. I have heard rumors of a universal jig in the works.
Overall, I like the purchase. The lowers themselves are nice and lightweight with a good finish. The jig sideplates, drill template, and mill template plates are coated, but, the router plate and spacer are not. I would prefer an "all or none" on the coating, but whatever. It would also be nice to have short pins pressed into the jig where it locates into the rear takedown hole. It currently uses a long bolt that goes completely through, so you have to be careful not to drill or mill through it. You take it out during 2 steps, but I could see that being a brain fart moment. The pins could be short enough to just insert in the hole, but not deep enough to be in the milling area. The threaded hole gets pretty clogged with chips during the process.
Overall, I have $150 in the jig, ~$40 in drill/mill bits and a drill stop. The router can be really any router with a 1/4 chuck. Took me like 2.5 hours on the first go, could probably be done in an hour or so if I wasn't taking my sweet time.
Lessons learned: Do this outside, it makes A LOT of aluminum splinters. Shop vac is not a bad idea. High rpm on the router gives a smoother finish.
A few photos of the process and end result are below.
http://i131.photobucket.com/albums/p302/mchl_wood/Misc/IMG_20140829_154601_621_zpsufkv1ay3.jpg (http://s131.photobucket.com/user/mchl_wood/media/Misc/IMG_20140829_154601_621_zpsufkv1ay3.jpg.html)http://i131.photobucket.com/albums/p302/mchl_wood/Misc/IMG_20140830_145212_964_zpsutlvydnk.jpg (http://s131.photobucket.com/user/mchl_wood/media/Misc/IMG_20140830_145212_964_zpsutlvydnk.jpg.html)http://i131.photobucket.com/albums/p302/mchl_wood/Misc/IMG_20140830_153923_230_zpsaikgu37i.jpg (http://s131.photobucket.com/user/mchl_wood/media/Misc/IMG_20140830_153923_230_zpsaikgu37i.jpg.html)http://i131.photobucket.com/albums/p302/mchl_wood/Misc/IMG_20140830_162359_794_zpsdx6bti1q.jpg (http://s131.photobucket.com/user/mchl_wood/media/Misc/IMG_20140830_162359_794_zpsdx6bti1q.jpg.html)http://i131.photobucket.com/albums/p302/mchl_wood/Misc/IMG_20140830_164819_663_zps1qk6sh9m.jpg (http://s131.photobucket.com/user/mchl_wood/media/Misc/IMG_20140830_164819_663_zps1qk6sh9m.jpg.html)http://i131.photobucket.com/albums/p302/mchl_wood/Misc/IMG_20140830_172027_354_zpsbyhqfeic.jpg (http://s131.photobucket.com/user/mchl_wood/media/Misc/IMG_20140830_172027_354_zpsbyhqfeic.jpg.html)http://i131.photobucket.com/albums/p302/mchl_wood/Misc/IMG_20140901_164603_914_zps7xt6ejfe.jpg (http://s131.photobucket.com/user/mchl_wood/media/Misc/IMG_20140901_164603_914_zps7xt6ejfe.jpg.html)http://i131.photobucket.com/albums/p302/mchl_wood/Misc/IMG_20140901_170659_035_zps11yf1nsn.jpg (http://s131.photobucket.com/user/mchl_wood/media/Misc/IMG_20140901_170659_035_zps11yf1nsn.jpg.html)http://i131.photobucket.com/albums/p302/mchl_wood/Misc/IMG_20140830_162413_422_zpsuvglnk0b.jpg (http://s131.photobucket.com/user/mchl_wood/media/Misc/IMG_20140830_162413_422_zpsuvglnk0b.jpg.html)
If you use just any router wouldn't you put strain on the bearings if it's not a plunge router?
I was under the impression that routers rotate way too fast for this kind of work. I'm in absolutely no position to argue that point any further though.
If you use just any router wouldn't you put strain on the bearings if it's not a plunge router?
You use a drill (or drill press) to get do depth initially, the router is doing side cutting only. In other words, the tools are used within their design. I used a small harbor freight drill press and a Dewalt DWP611 compact router.
I was under the impression that routers rotate way too fast for this kind of work. I'm in absolutely no position to argue that point any further though.
It ran great at ~24k rpm using a 3 flute end mill.
BuffCyclist
09-02-2014, 21:49
I was under the impression that routers rotate way too fast for this kind of work. I'm in absolutely no position to argue that point any further though.
Speeds and feeds. You can apply these basic calculations for milling here. Lower will be 7075 or possibly 6061 alum. Pick your tool and determine the speed and you can calculate what size end mill you can use.
Or, spin as fast as possible and use TONS of lube.
Quick tip, if you're too cheap/lazy to buy real cutting fluid/oil, WD40 will work in a pinch.
skullybones
09-03-2014, 11:28
RPM Formula (12 * sfm) / (Pi * Diameter)
24K is perfectly within the limits of a ~1/4" Carbide Endmill in either series of aluminum. Lube is definitely preferred to help prevent galling between the Carbide tool and work-piece, but it will be messy with this setup. Check out tools with a ZRN Coating. They run great in Aluminum.
Use very light depth of cut to mitigate most galling. Blow out chips often as you create a variable chipload on your tool when they are re-cut.
If the tool dulls or chips, replace it.
Have fun! Keep your fingers attached.
BuffCyclist
09-03-2014, 11:52
RPM Formula (12 * sfm) / (Pi * Diameter)
24K is perfectly within the limits of a ~1/4" Carbide Endmill in either series of aluminum. Lube is definitely preferred to help prevent galling between the Carbide tool and work-piece, but it will be messy with this setup. Check out tools with a ZRN Coating. They run great in Aluminum.
Use very light depth of cut to mitigate most galling. Blow out chips often as you create a variable chipload on your tool when they are re-cut.
If the tool dulls or chips, replace it.
Have fun! Keep your fingers attached.
See, I knew if I just said speeds and feeds someone would come along and provide the formula for me because I was too lazy to write it out. [Tooth]
ChunkyMonkey
09-03-2014, 12:22
Good job, looks great
smokeyradio
09-05-2014, 08:51
Great review and nice work. I have been looking at getting one of these for
a few weeks, thanks for the review. I saw this one this morning and it is universal.
http://www.modulusarms.com/
balyon885
09-06-2014, 18:35
Anyone have experience with this jig? Thinking about dabbling in 80% lowers, advice on which jig to use?
Will probably go with an Anderson 80% lower.
Yup. Doing another lower in mine as soon as I work up the energy to get off the couch.
https://www.ar-15.co/threads/137693-80-Arms-Easy-Jig
A tip: put a piece of tape right where the safety selector hole goes. When you drill it, the aluminim chips/shavings will try to ride around with the drill bit and wear on the anodizing. The jig is not presently designed to be universal, you may have to do a bit of trickery with a dremel to fit other lowers...
Great review and nice work. I have been looking at getting one of these for
a few weeks, thanks for the review. I saw this one this morning and it is universal.
http://www.modulusarms.com/
That is almost something that a co-op could jointly purchase and keep in a location frequented by members. [Party1]
Great-Kazoo
09-06-2014, 20:37
^^ This^^
^^ This^^
Somebody mentioned something like a co-op in another very similar thread. [Beer]
theGinsue
09-07-2014, 00:55
merged
Great-Kazoo
09-07-2014, 01:32
Somebody mentioned something like a co-op in another very similar thread. [Beer]
Down side is someone lent it to a friend who OOPS "kind of broke it" pieces of jig never showed up to next in line. Or person waiting, is still waiting due to an issue with previous user.
OR they lent it to some one, who was going to make a copy so there would be 2. BUT that person hasn't heard from their machinist friend, since their wife asked for a divorce.
I'm out.
balyon885
09-07-2014, 16:57
Ordered their universal jig today. Uses a drill press with an endmil rather than a router, and was 50 bucks cheaper.
We will see how it all works out with my Anderson 80% I ordered today too.
Ordered their universal jig today. Uses a drill press with an endmil rather than a router, and was 50 bucks cheaper.
We will see how it all works out with my Anderson 80% I ordered today too.
Which jig did you order? I finished my 80% with the universal jig from 80% Arms. The lower came out very nice. I was originally going to order the jig from CNC Guns, mainly because it looked like something that would last forever, but it got too expensive when I added the adapter plates. (If money is not a concern, I think the CNC Guns jig is a great jig, but I didn't need the extra features for about $275.) The 80% Arms jig is also real solid and it will last for as many lowers as I can afford to do on it.
When I get settled in I plan to strip my two other lowers, sell them, and replace them with 80% lowers. (Yes, I'm paranoid.) I'll probably sell my universal jig and get the router jig from 80% Arms. It's not universal but I've seen a few posts with details to easily convert it to universal. 80% Arms probably wanted people to buy their lowers along with their jigs but the internet figured out how to get around that. :p I got turned off with some stuff I saw posted by Modulus jig company so they won't get my money. Like my momma said, if you can't say something good about someone, then don't say anything at all. Nuf said.
Final tip. I thought I had messed up the outside finish of my lower when I finished milling it. It looked like the anodized coating was worn in some parts. But it was just aluminum shavings and powder that rubbed against the finish. I got a sponge with the green side that is made to clean pots and washed the lower down using soap and water. The aluminum rubbed off the anodized finish and it looked like new again. :)
balyon885
09-09-2014, 01:07
Got the cheaper one that uses just a drill press, since I already have a harbor freight drill press.
Got the cheaper one that uses just a drill press, since I already have a harbor freight drill press.
I did mine on a cheap Harbor Freight drill press too! In case you have not used the HF drill press to do one yet, here are a couple things I learned. The HF drill press is not that sturdy. Don't put too much down force on the drill as the drill table can flex. Check your chuck frequently when milling. Each time I checked mine I had to tighten it up again. It might mess up your finish if the end mill got loose and wobbled around before you could stop it. I can't think of much more than that. It was a fun project and I like telling people I literally built my AR myself. Non gun people who don't know about 80% lowers look at you like you are some extremist freak! Then when you tell them it doesn't have to be registered it really blows their mind. Haha.
Then when you tell them it does have to be registered it really blows their mind. Haha.
Huh?
Typo - * doesn't have to be registered.
Typo - * doesn't have to be registered.
It doesn't have to be registered anyway, but we know what you mean.
Great-Kazoo
09-09-2014, 20:33
I did mine on a cheap Harbor Freight drill press too! In case you have not used the HF drill press to do one yet, here are a couple things I learned. The HF drill press is not that sturdy. Don't put too much down force on the drill as the drill table can flex. Check your chuck frequently when milling. Each time I checked mine I had to tighten it up again. It might mess up your finish if the end mill got loose and wobbled around before you could stop it. I can't think of much more than that. It was a fun project and I like telling people I literally built my AR myself. Non gun people who don't know about 80% lowers look at you like you are some extremist freak! Then when you tell them it doesn't have to be registered it really blows their mind. Haha.
Side force on the bearings of the chuck from the end mill are one of the problems you're having. I know people use drill presses for these projects, myself, i'd use a mill. Even one of those table tops units. Yes not everyone has access to a mill and a drill press does work. I'd be real leary of doing more than 1-2 using a drill press, tops.
balyon885
09-11-2014, 21:23
Got my jig today, lower comes tomorrow.
balyon885
09-12-2014, 19:26
The Anderson lower fits in the 80% arms universal jig no problem. Got some drilling done, what a mess it makes.
Anyone know where to get end mills locally, need a 1/4 and a 3/8 that are at least 2.5 inches long.
skullybones
09-12-2014, 21:27
Triad Tooling will get you hooked up. Down this way Cutting Edge Tool Supply.
The Anderson lower fits in the 80% arms universal jig no problem. Got some drilling done, what a mess it makes.
Anyone know where to get end mills locally, need a 1/4 and a 3/8 that are at least 2.5 inches long.
I will trade you a 4" 1/4 end mill 1 1/2 cut if you order and ship the end mill from 80% arms to my house.
balyon885
09-13-2014, 02:12
I will trade you a 4" 1/4 end mill 1 1/2 cut if you order and ship the end mill from 80% arms to my house.
Huh?
Huh?
I bought an extra end mill for mine. It is 1/4" diameter, 4" long end mill. 1 1/2" length of cut. You order and ship to my address, I hand you my bit. (new in package)
It is the same price (ish).
Basically, buy me the replacement, and I hand you one. I'm not in the immediate need for one. Have one on the way for me and I'm good.
Basically, place the order, show me confirmation, and as long as it is legit, I can wait for the bit to come in. I paid ~$24 for the bit plus shipping. I have another, so I don't really NEED it right now.
ETA: or, PayPal me like $30 and I will order it myself. (fees suck)
balyon885
09-13-2014, 02:39
I need the 3/8th sized one the most. My lower had most of the rear pocket opened and thats all the universal jig uses the 1/4 one for.
balyon885
09-14-2014, 14:14
Got it milled out, walls look pretty good few hills and such but the bottom is still pretty rough. Going to try and clean it up some more. Got a lpk to check and see if it will work tolerance wise. Don't care so much if it looks bad as long as it works. After all, it is my first attempt.
I've seen lots of photos of 80% lowers where the bottom looks a little rough from going a little to far with the drill. It is not something specific to any brand jig, but from not measuring properly. I'd recommend going a little shallow with the drill and that way when you finish milling it out there will be no dimples on the bottom. It's purely cosmetic and nobody will notice once you install the LPK. But for anyone anal and OCD types, just drill out the pocket a little shallow - maybe 1/16" or so. You may need to make a couple more passes with the end mill until you are the the spec depth but in the end you'll have a nice smooth bottom on your lower. I took my time and measured everything like 3 times to make sure I didn't cut too deep. It was messy but a fun project. Next time I'm going to have the shop-vac running the entire time I'm drilling or milling to try to catch all the stuff as it comes out.
balyon885
09-15-2014, 20:25
I got the bottom cleaned up but over milled the area by the hammer pin. Needless to say, I'm ordering another one.
Bummer. Go slow and measure twice everything. If you mess up one the lowers from 80% Arms they will replace it for half price.
balyon885
09-16-2014, 07:48
I'm using then Anderson ones, only 45 bucks. So not a horrible hit.
james_bond_007
10-12-2014, 13:46
Side force on the bearings of the chuck from the end mill are one of the problems you're having. I know people use drill presses for these projects, myself, i'd use a mill. Even one of those table tops units. Yes not everyone has access to a mill and a drill press does work. I'd be real leary of doing more than 1-2 using a drill press, tops.
I would consider the type of work and material to be 'light' machining (especially if you mill out in small increments).
I came across this "adapter" for a drill press that, on the surface, seems pretty easy to make.
It also looks like, for they type of work we are talking about, would take the lateral load off the drill press bearings.
http://books.google.com/books?id=AuADAAAAMBAJ&pg=PA191&dq=drillpress+milling&lr=&as_pt=MAGAZINES&cd=2#v=onepage&q&f=true
I have concerns that too much lateral force might move the jig, though.
Your thoughts ?
(Here's a brief overview)
50853
Great-Kazoo
10-12-2014, 16:58
I got the bottom cleaned up but over milled the area by the hammer pin. Needless to say, I'm ordering another one.
Depending how far off, you might consider shimming the H/T/S , making sure it is centered.
http://www.brownells.com/gunsmith-tools-supplies/sight-scope-installation-tools/scope-shims/kit-no-ac-24-steel-shim-stock-prod589.aspx
balyon885
10-12-2014, 19:51
I thought about a drop in trigger too.
End Mills..... Go to eBay, I secured a 4 flute 3/8" HSS and a 1/8" HSS for $7.20 (including shipping)!!
:Cool:
Another recommendation I found with some research, if using a drill press, a slide vise helps BIG TIME!
FYI:
Jig: 79.00 with drill bits
End Mills: 7.20
I have a drill press
Slide vice: 45.00 (eBay)
Lower: 47.00
A milled stripped lower (no S/N) for less than 135.00!
Thinking out load, having made the investment, there may be a possibility of rental periods for members in the future.......
:Cool:
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