What jig? What method?

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[ARCHIVED THREAD] - What jig? What method?

Posted: 8/21/2016 10:58:48 PM EDT

Hello, I'm about to start my first AR build. It will also be my first AR. I already have a 80 lower from Modulus arms. I'm unsure of what jig I should buy and what method to use....I have a kobalt drill, but I have access to a drill press. I don't have a router, but can buy one if you guys think it would be the better way.

Posted: 8/21/2016 11:06:10 PM EDT

[#1]

Quoted:
Hello, I'm about to start my first AR build. It will also be my first AR. I already have a 80 lower from Modulus arms. I'm unsure of what jig I should buy and what method to use....I have a kobalt drill, but I have access to a drill press. I don't have a router, but can buy one if you guys think it would be the better way.

View Quote

Modulus, HD or regular jig dependng on how many you plan to make. Use a drill press to extend the life of your jig. Get the router - they are not expensive. I used the Makita and worked slowly (1/16" per pass with the endmill).

Posted: 8/22/2016 12:16:35 AM EDT

[#2]

Modulus HD jig, drill press and a Modulus recommended router. Take your time and your lowers will turn out beautiful.

Posted: 8/22/2016 8:18:26 AM EDT

[#3]

The Modulus HD jig is awesome. I'd recommend the American Gunsmithing Tooling end mills https://americangunsmithtooling.com/products/1-4-0-75-short-flute-solid-carbide-and-zrn-coated-end-mill-100-made-in-america
They cut like butter and barely any chatter.

Posted: 8/22/2016 9:51:27 AM EDT

[#4]

Modulus HD jig, Modulus tooling kit, Modulus Speed Drill Kit and one of their recommended routers... I've got the Makita, but the Rigid and the Dewalt that are on the good list also look like great routers. I was actually going to buy the Rigid but it was out of stock at the Home Depot near my house and they had the Makita there at the same price. Anyway, I've done several lowers with this setup. I've also got one of the bigger Harbor Freight drill presses but the last several lowers I've done I've used the Speed Drill Kit and a Rigid 18V cordless drill.

Anyway, in my opinion the Modulus HD is the best jig on the market and the Modulus guys are super nice and active on this forum.

Posted: 8/22/2016 12:16:14 PM EDT

[#5]

Thank You for all for the kind words. We are very proud of our jig and it is great to see all the enthusiastic replies.

My personal favorite router for these is the Ridgid R24012, but we also have folks here who really like the Dewalt DPW611 and the Makita RT0701C too.

Posted: 8/22/2016 12:26:30 PM EDT

[#6]

Quoted:
Hello, I'm about to start my first AR build. It will also be my first AR. I already have a 80 lower from Modulus arms. I'm unsure of what jig I should buy and what method to use....I have a kobalt drill, but I have access to a drill press. I don't have a router, but can buy one if you guys think it would be the better way.

View Quote

Well I'm sure you already know which jig I am going to recommend

But I really encourage you to pick up a router. You will achieve much better results than using a drill press for the milling portion. Drill presses are not designed or properly supported for side loading. They are designed to cut vertically only.

Posted: 8/22/2016 3:44:43 PM EDT

[#7]

Remember to set your drill depth a smidge shollow to avoid dimpling on the bottom of the fire control group.

Posted: 8/22/2016 5:23:27 PM EDT

[#8]

Here's what I recommend...

http://www.modulusarms.com/Modulus-Arms-heavy-duty-universal-ar-15-80-lower-receiver-jig/
http://www.modulusarms.com/jig-fabrication-tool-kit/
http://www.modulusarms.com/sale-speed-drill-kit/

http://www.homedepot.com/p/RIDGID-5-5-Amp-Corded-Compact-Router-R24012/100337039
http://www.homedepot.com/p/BESSEY-4-in-Drill-Press-Vise-BV-DP40/205023096
http://www.homedepot.com/p/BESSEY-1-in-Drop-Forged-C-Clamp-with-1-in-Throat-Depth-CM10/205512963 (get two)
http://www.homedepot.com/p/RIDGID-18-Volt-Lithium-Ion-1-2-in-Cordless-Compact-Drill-Driver-Kit-R860052K/205690161
http://www.homedepot.com/p/UltraLube-2-oz-Drilling-and-Tapping-Fluid-10664/203919373

You can get the last 5 items from a lot of places... I just list it from Home Depot because it is a convenient place that carries all those items and you can either order online or get it in store across most of the country. Just about any 3/8" hand drill either cordless or electric will do, but I personally have the one I list and like it. A lot of drilling and tapping fluids will work, that's just the one that I happened to find on Home Depot's web site. The drill press vice makes keeping the jig steady on a flat surface much easier, even if you aren't using it with a drill press. The C clamps can be used to keep the drill press vice from sliding around. Clamp the vice down to a workbench, table or counter top. In my opinion the more solid the jig is set up the easier it is to keep the trim router perfectly vertical and maintain smooth and consistent speed and pressure moving it. And that seems to be the key to getting good smooth cutting.

Posted: 8/22/2016 6:30:07 PM EDT

[#9]

Not that ANYONE recommended it, BUT....

The Modulus Arms HD Jig, that's all you need to know!

Posted: 8/22/2016 6:50:38 PM EDT

[#10]

Thanks guy's, Modulus HD it is. I will also buy one of the recommended router's thanks a lot! :)

Posted: 8/22/2016 6:58:07 PM EDT

[#11]

It looks like one or two people seem to like the modulus jig ;)

I used the jig from 80-lower.com. By itself it looks like it currently costs $195 and includes the drill bits and end mill. I was successful in completing a couple lowers with this jig but did have a little difficulty on the second one with the hole alignment for the safety selector (I think my drill press table wasn't quite level). I have another one I'll be starting soon and feel confident that I'll end up with a workable finished product. I also thought the instructions were very good for this jig and the customer support was great when I had questions.

Has anyone out there used the 80-lower jig AND the modulus? Just curious if the modulus is that much better...

Posted: 8/22/2016 8:00:26 PM EDT

[#12]

Quote History

Quoted:
It looks like one or two people seem to like the modulus jig ;)

I used the jig from 80-lower.com. By itself it looks like it currently costs $195 and includes the drill bits and end mill. I was successful in completing a couple lowers with this jig but did have a little difficulty on the second one with the hole alignment for the safety selector (I think my drill press table wasn't quite level). I have another one I'll be starting soon and feel confident that I'll end up with a workable finished product. I also thought the instructions were very good for this jig and the customer support was great when I had questions.

Has anyone out there used the 80-lower jig AND the modulus? Just curious if the modulus is that much better...

View Quote

It looks like 80-lower.com resells the 80% Arms EZ Jig. 80percentarms.com and 80-lower.com are not the same company. I haven't used the 80% Arms EZ Jig, so I can't say anything bad about it. It is comparable to the original Modulus Universal Jig in design, materials and construction. 80% Arms also now as a steel version of their jig that is more comparable to the Modulus HD jig. Again, I haven't tried one so I can't really say much about it other than what I've heard. If you already have the EZ Jig I would probably say to stick with it. I chose the Modulus jigs based primarily on that they were supposed to be more universal in accepting just about any brand of lower and also that the Modulus people are active here on this group. If I had to buy another jig I'd get the Modulus HD again and it is the one I recommend. That said, I have no doubt that the EZ jig will make correct lowers as well, so it is really good news that you probably can't go wrong either way.

Posted: 8/23/2016 5:11:20 AM EDT

[#13]

Quote History

Quoted:
That said, I have no doubt that the EZ jig will make correct lowers as well, so it is really good news that you probably can't go wrong either way.

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I have not used the EZ jig, either, but I did look at one the other day. I noticed they are engraved with drill sizes pointing to the holes on the side plates. I wondered if that's where the "EZ" comes in. That might come in handy for people like myself who don't have the memories they used to.

Posted: 8/23/2016 7:30:57 AM EDT

[#14]

I've used both. The Modulus HD buy far withstands "oops" moments much better

Posted: 9/13/2016 2:21:51 AM EDT

[#15]

the modulus hd jig was awesome, I now have my rifle built. the upper from Ptac fits perfectly to the Modulus lower.... no up and down play at all, and barely noticeable side to side play. Now I just got to find someone to test fire it...haha

Posted: 9/13/2016 4:05:07 PM EDT

[#16]

Quote History

Quoted:
the modulus hd jig was awesome, I now have my rifle built. the upper from Ptac fits perfectly to the Modulus lower.... no up and down play at all, and barely noticeable side to side play. Now I just got to find someone to test fire it...haha

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Congratulations 80%er!

Posted: 9/13/2016 5:40:09 PM EDT

[#17]

Quote History

Quoted:
the modulus hd jig was awesome,

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Thank You for your feedback

Posted: 9/14/2016 8:26:09 AM EDT

[#18]

What HP Router from Lowes or Harper Freight is too small to use to cut Aluminum? No Home Depot. It Closed Up.

Posted: 9/14/2016 8:54:17 AM EDT

[#19]

What HP Router from Lowes or Harper Freight is too small to use to cut Aluminum? No Home Depot. It Closed Up.

Posted: 9/14/2016 11:28:07 AM EDT

[#20]

Quote History

Quoted:
What HP Router from Lowes or Harper Freight is too small to use to cut Aluminum? No Home Depot. It Closed Up.

View Quote

Dewalt DWP611 from lowes. There is no router available from HF that we endorse and we tried several.

There is router information on our website in the FAQ section.
There is also a lengthy router thread here on ar15.com too

Posted: 9/14/2016 12:12:21 PM EDT

[#21]

Quote History

Quoted:
What HP Router from Lowes or Harper Freight is too small to use to cut Aluminum? No Home Depot. It Closed Up.

View Quote

No Home Depot??? Y'all must be way out in the boonies...

This is the one Maxxx is talking about... appears to be the only appropriate one that Lowe's sells...

http://www.lowes.com/pd/DEWALT-1-25-HP-Variable-Speed-Fixed-Corded-Router/3316758

FWIW, you can still buy the Rigid or Makita routers that Home Depot sells if you order from their web site. They will ship to you. You can also find them from a lot of other online sellers including on Amazon, eBay and many others.

http://www.homedepot.com/p/RIDGID-5-5-Amp-Corded-Compact-Router-R24012/100337039

That's the Rigid one, on sale $99 and free shipping to your home.

If you like Makita better, it is the same price:

http://www.homedepot.com/p/Makita-1-1-4-HP-Compact-Router-RT0701C/204247210

You can even order the DeWalt from them if you want although it is $119.

http://www.homedepot.com/p/DEWALT-1-25-HP-Variable-Speed-Compact-Router-DWP611/202562625

There are also some inexpensive deals to be found on used or reconditioned ones online if you google it... Just buy one of the recommended models... DeWalt DWP611, Rigid R24012 or Makita RT0701C and you'll be good.