I recently took the plunge into an 80% lower project. I wanted a lower which was completely blank, allowing me to do my own markings & engraving designs. So last fall I purchased three 80% Billet lowers from STEALTH ARMS at the 1500. (It would appear they are now currently only offering forged lowers).
As much as I'd like to get a mini mill, I just wouldn't end up using it very much to justify the cost in purchasing it (and additional cost in upgrading it). Because of the recent ATF ruling (making it appear to be problematic to borrow mills, tools, etc.), I opted to try the 80% ARMS Easy Jig for $150. Their jig was attractive to me because of price, and apparent ease of use. It requires a drill & router, and basic tools experience. Having very little machining experience, I put this jig to the test this weekend.
Below: 2 Milled lowers using the Easy Jig, 1 unmilled.
Everything comes in a tidy box including the jig assembly, spacers, bolts & bits. Instructions can be found on their website, which consist of a PDF manual, and a video walk through. The instructions (both versions) are really informative, and make it easy for someone with my limited experience.
Milling the lower involves the following steps, and took about 3 hours to complete (once familiar with the process).
1) Drill holes for main pocket & rearshelf using a hand drill or drill press.
2) Mill the main pocket using your router
3) Mill the rear shelf pocket using your router
4) Drill a pilot hole & mill the trigger pocket cutout
5) Drill trigger pin holes & safety Selector hole.
SAFETY REMINDER:
GOGGLES (full googles, not safety glasses that are open on the sides) and Ear Pro are an absolute must here. Aluminum shavings in the eyeball aren't going to be fun whatsoever, and magnets don't work on aluminum.
Clothing and work boots appropriate for working around metal. You will get a lot of metal shavings flying about.
I wore a dust mask as well.
Jig pieces have built in depth indicators. These are used for both drilling and routing. The supplied slip collar can come loose, so I was sure to check it after each hole was drilled. On the 2nd lower, I wasn't worried about getting full depth, as the router can mill to the proper depth in the final steps. I didn't want to risk drilling too deep accidentally. WD-40 seemed to work well for lubricating the drill bits and endmill bit. Compressed air is handy for clearing out debris.
The first step is to drill out the main pocket. This gets much of the material out of the way, allowing the router/mill process to go more smoothly. Drilling these holes using my hand drill took about 45 minutes.
When completed, you have a bunch of holes in the main pocket area. The lowers I purchased, had a portion of the rear shelf milled already, so I did not need to drill those two rear holes (which requires removing the rear sidewall bolt)
With that out of the way, it's time to setup for the router. The Easy Jig has spacers, jig template, and plate which clears the rear portion of the lower.
Later, when milling the trigger pocket hole, the plate is removed, which made it pretty tight for my router. I had to remove the plastic base off of my router for this step (and when the photo was taken). I have a middle of the road, nothing fancy about it Ryobi 1 1/2 hp router. I've used it for various wood projects, but this is the first I've used it on metal. This model does not have any LED lighting, which would have been really handy and easier for my aging eyes to see.
What I do like about my router, is the measured adjustments which can be made via the depth dial ring. Easy Jig recommends adjusting the router to a depth of about 1/3rd of a hash mark (on the depth gauge shown earlier) after each pass. I found on my router, that 1/16th inches was just right. So instead of comparing to the jig depth indicator after each pass, I simply dialed another 16th, and moved on.
I cannot stress enough the importance of full goggles for eye protection. This process really throws very small shavings of aluminum everywhere, usually directly at you. I also wore a dust mask, ear protection, and a junk button down shirt, jeans & workboots.
This is the most time consuming portion. You start in a drilled hole, and then work your way around using the jig. The mill bit is a bit high on the first two passes, so you don't get right up against the jig wall until after your cutting flutes on the mill bit are below the jig sides (to avoid cutting up your jig). Slow and steady wins the race. Once you get near the bottom of your drill holes, then I start comparing to the gauge. Your final pass will be a bit of a plunge cut, as it will go below the drill holes, leaving you a smooth finish at the bottom of the pocket.
Partway through the milling process of the main pocket
One issue I discovered during the first lower, is that my router has a slight bit of flex in it when using the jig wall as a guide, and the long endmill bit. It left a bit of a ridge partway down the pocket. I attempted to go back and clean it up, and discovered the problem. I was positioned at the back of the lower for the entire process. But noticed the sidewalls would smooth out if I then moved to the side, and then the front of the lower. Sort of attacking it from all angles. I'd do my pass, stop the router. Move to the side of the lower, and make a pass around the perimeter, and then repeat from the front side of the lower. This slowed the process down a bit more on the 2nd lower, but the result was much better than the first.
In all, it took 1 hour and 45 minutes to route the main pocket.
The rear shelf was partially milled on my lower, so that combined with the shorter overall depth, resulted in only 15 minutes to mill the rear pocket.
Afterwards, you then remove the plate, and follow instructions to drill a hole for the trigger pocket cutout, which is then milled. This process also only took about 15 minutes to setup & drill/cut.
After that, you drill the trigger pin holes & safety selector (using the holes found in the jig sidewalls) to finish the lower.
In all, the 2nd lower went much faster, having been familiar with the process, and it took 3 hours from start to finish.
The two finished lowers. The first is found in the top portion of the photo, and the 2nd is the bottom one.
You can notice the ridges I mentioned in the walls of the first lower compared to the 2nd smoother walls in the photo below.
...And then there is this:
I managed to mill out a trigger pocket hole in the trigger guard! Don't ask.
Now I need to find a way to
A) Fix it
B) Make it look like it was intentional
Overall, I would recommend the Easy Jig as a low cost option, that's pretty simple for inexperienced folks to use. As long as you do your part, Easy Jig will do it's part. And don't make the same mistakes I did!
Easy Jig Instructional Video:
[video=youtube;SiHdV5slQps]https://www.youtube.com/watch?v=SiHdV5slQps[/video]
UPDATE: I've test fitted trigger, hammer & safety selector without issue. the front of the hammer is very close to the front of the pocket, but moves freely in both lowers. I can see faint rub marks on one receiver where contact was made. I will sand this back/smooth it a bit.
As much as I'd like to get a mini mill, I just wouldn't end up using it very much to justify the cost in purchasing it (and additional cost in upgrading it). Because of the recent ATF ruling (making it appear to be problematic to borrow mills, tools, etc.), I opted to try the 80% ARMS Easy Jig for $150. Their jig was attractive to me because of price, and apparent ease of use. It requires a drill & router, and basic tools experience. Having very little machining experience, I put this jig to the test this weekend.
Below: 2 Milled lowers using the Easy Jig, 1 unmilled.
Everything comes in a tidy box including the jig assembly, spacers, bolts & bits. Instructions can be found on their website, which consist of a PDF manual, and a video walk through. The instructions (both versions) are really informative, and make it easy for someone with my limited experience.
Milling the lower involves the following steps, and took about 3 hours to complete (once familiar with the process).
1) Drill holes for main pocket & rearshelf using a hand drill or drill press.
2) Mill the main pocket using your router
3) Mill the rear shelf pocket using your router
4) Drill a pilot hole & mill the trigger pocket cutout
5) Drill trigger pin holes & safety Selector hole.
SAFETY REMINDER:
GOGGLES (full googles, not safety glasses that are open on the sides) and Ear Pro are an absolute must here. Aluminum shavings in the eyeball aren't going to be fun whatsoever, and magnets don't work on aluminum.
Clothing and work boots appropriate for working around metal. You will get a lot of metal shavings flying about.
I wore a dust mask as well.
Jig pieces have built in depth indicators. These are used for both drilling and routing. The supplied slip collar can come loose, so I was sure to check it after each hole was drilled. On the 2nd lower, I wasn't worried about getting full depth, as the router can mill to the proper depth in the final steps. I didn't want to risk drilling too deep accidentally. WD-40 seemed to work well for lubricating the drill bits and endmill bit. Compressed air is handy for clearing out debris.
The first step is to drill out the main pocket. This gets much of the material out of the way, allowing the router/mill process to go more smoothly. Drilling these holes using my hand drill took about 45 minutes.
When completed, you have a bunch of holes in the main pocket area. The lowers I purchased, had a portion of the rear shelf milled already, so I did not need to drill those two rear holes (which requires removing the rear sidewall bolt)
With that out of the way, it's time to setup for the router. The Easy Jig has spacers, jig template, and plate which clears the rear portion of the lower.
Later, when milling the trigger pocket hole, the plate is removed, which made it pretty tight for my router. I had to remove the plastic base off of my router for this step (and when the photo was taken). I have a middle of the road, nothing fancy about it Ryobi 1 1/2 hp router. I've used it for various wood projects, but this is the first I've used it on metal. This model does not have any LED lighting, which would have been really handy and easier for my aging eyes to see.
What I do like about my router, is the measured adjustments which can be made via the depth dial ring. Easy Jig recommends adjusting the router to a depth of about 1/3rd of a hash mark (on the depth gauge shown earlier) after each pass. I found on my router, that 1/16th inches was just right. So instead of comparing to the jig depth indicator after each pass, I simply dialed another 16th, and moved on.
I cannot stress enough the importance of full goggles for eye protection. This process really throws very small shavings of aluminum everywhere, usually directly at you. I also wore a dust mask, ear protection, and a junk button down shirt, jeans & workboots.
This is the most time consuming portion. You start in a drilled hole, and then work your way around using the jig. The mill bit is a bit high on the first two passes, so you don't get right up against the jig wall until after your cutting flutes on the mill bit are below the jig sides (to avoid cutting up your jig). Slow and steady wins the race. Once you get near the bottom of your drill holes, then I start comparing to the gauge. Your final pass will be a bit of a plunge cut, as it will go below the drill holes, leaving you a smooth finish at the bottom of the pocket.
Partway through the milling process of the main pocket
One issue I discovered during the first lower, is that my router has a slight bit of flex in it when using the jig wall as a guide, and the long endmill bit. It left a bit of a ridge partway down the pocket. I attempted to go back and clean it up, and discovered the problem. I was positioned at the back of the lower for the entire process. But noticed the sidewalls would smooth out if I then moved to the side, and then the front of the lower. Sort of attacking it from all angles. I'd do my pass, stop the router. Move to the side of the lower, and make a pass around the perimeter, and then repeat from the front side of the lower. This slowed the process down a bit more on the 2nd lower, but the result was much better than the first.
In all, it took 1 hour and 45 minutes to route the main pocket.
The rear shelf was partially milled on my lower, so that combined with the shorter overall depth, resulted in only 15 minutes to mill the rear pocket.
Afterwards, you then remove the plate, and follow instructions to drill a hole for the trigger pocket cutout, which is then milled. This process also only took about 15 minutes to setup & drill/cut.
After that, you drill the trigger pin holes & safety selector (using the holes found in the jig sidewalls) to finish the lower.
In all, the 2nd lower went much faster, having been familiar with the process, and it took 3 hours from start to finish.
The two finished lowers. The first is found in the top portion of the photo, and the 2nd is the bottom one.
You can notice the ridges I mentioned in the walls of the first lower compared to the 2nd smoother walls in the photo below.
...And then there is this:
I managed to mill out a trigger pocket hole in the trigger guard! Don't ask.
Now I need to find a way to
A) Fix it
B) Make it look like it was intentional
Overall, I would recommend the Easy Jig as a low cost option, that's pretty simple for inexperienced folks to use. As long as you do your part, Easy Jig will do it's part. And don't make the same mistakes I did!
Easy Jig Instructional Video:
[video=youtube;SiHdV5slQps]https://www.youtube.com/watch?v=SiHdV5slQps[/video]
UPDATE: I've test fitted trigger, hammer & safety selector without issue. the front of the hammer is very close to the front of the pocket, but moves freely in both lowers. I can see faint rub marks on one receiver where contact was made. I will sand this back/smooth it a bit.
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