Before I start milling a 80% lower

[NatetheGr8]

So I bought a new mini mill from a guy I met at the gunstore who bought it to do 80% lowers, but he figured it was to much for him so he sold it to me cheap. Anyway I wanted to know what I need to start milling I've collected some scattered research( here on CG,YouTube, some ar blueprints and etc.) and I have some of the stuff I need; I have a ASA 95% lower, a 0rd pmag( 20rd blocked with a minus 20rd magblock magblock) and of course the mill. I know the other stuff I need, like a vise,jig, endmills, collets and digital readout displays. My question is do I need the digital readouts and collets? Do I need a collet for every size endmill I have or will one collet do for this project? And will this vise, jig and Endmil set work?

Vise:

http://littlemachineshop.com/products/product_view.php?ProductID=3767&category=1963256914

Endmill/Jig:

http://www.gunbroker.com/Auction/ViewItem.aspx?Item=458507816

Sorry for the lengthy post but i want all the info ican get before I dive into it. So by all mean give me a crash course. Thanks

[jaymz]

Yes. You need a collet for each end mill size. Though you could probably just put the end mills in a drill chuck and be perfectly fine for milling an AR type lower. DRO's aren't needed, but it will make measuring and cutting a bit quicker and more precise than measuring with a caliper.

[M1NM]

End mills are usually 3/8 and 1/2 inch shanks. Drill chucks have too much runout. If the chuck is held by a taper the cutter will tend to pull it out. You won't need a jig since you will be using a mill that lets you move .001 of an inch. There are a lot of prints on the web. Compare them and you'll see some different dimensions - use the most common dimension or check them on a finished lower. I found some lowers that had the mag well broached and top surface milled. Bought 3 of them for $45 from another CalGunner. I called them 20% lowers. If you're only doing one or two that may not be the route you want to go since you'll need to buy more tooling like the large drill and tap for buffer tube.

[toddh]

End mills are usually 3/8 and 1/2 inch shanks. Drill chucks have too much runout. If the chuck is held by a taper the cutter will tend to pull it out. You won't need a jig since you will be using a mill that lets you move .001 of an inch. There are a lot of prints on the web. Compare them and you'll see some different dimensions - use the most common dimension or check them on a finished lower.

He said collet, which are drawn into the spindle with a threaded rod.


I believe there are links to prints right at the top of this page.
A quick image search will get you more.
You may have use a marking dye and scribe your lines on your part.
A good pair of calipers will be mandatory.

End mill diameter can vary depending on the type of endmill you buy.
You will have to use a longer endmill to reach the required depth of the pocket. so it's a good idea to invest in a set of collets.
You also need to identify what type of collets you need.

I would suggest searching a little more here in the gunsmithing section for more info on what others have used....also youtube, and some machining forums.

Enco and wt tools are good resources for tooling.


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[tr6guns]

Here are a couple more inexpensive web sites for milling tools..

http://www.shars.com/

http://www.cdcotools.com/index.php

[NatetheGr8]

Someone got a place to they know on where to buy a set of collets at a good price? Also are the endmills in the jig/endmill combo set (see link of first post) adequate enough to " check that box of the list"?

[NatetheGr8]

He said collet, which are drawn into the spindle with a threaded rod.


I believe there are links to prints right at the top of this page.
A quick image search will get you more.
You may have use a marking dye and scribe your lines on your part.
A good pair of calipers will be mandatory.

End mill diameter can vary depending on the type of endmill you buy.
You will have to use a longer endmill to reach the required depth of the pocket. so it's a good idea to invest in a set of collets.
You also need to identify what type of collets you need.

I would suggest searching a little more here in the gunsmithing section for more info on what others have used....also youtube, and some machining forums.

Enco and wt tools are good resources for tooling.


.

If I were to get the digital readout display would I still need a set of calipers or would that not be needed at that point?

[NatetheGr8]

Also I forgot to mention this in the first post but it's a Harbor Freight central machining mini mill if that plays a part in all this, so if you have/had experience or knowledge on this mini you'll be a big help to me. I plan on buying some of the stuff the other guy on this thread posted; but I still have no clue on what collet to buy R8? Or 3morse? I'll try and look myself but if anyone knows of the top it help a lot. Thanks

[toddh]

Also I forgot to mention this in the first post but it's a Harbor Freight central machining mini mill if that plays a part in all this, so if you have/had experience or knowledge on this mini you'll be a big help to me. I plan on buying some of the stuff the other guy on this thread posted; but I still have no clue on what collet to buy R8? Or 3morse? I'll try and look myself but if anyone knows of the top it help a lot. Thanks

Seriously...your gonna have to look up the model number online and see what it takes....or post pics or give us a model number.

Your gonna have to go on the websites suggested and educate yourself a little on tooling types, and research in threads or on the web what others are using for tooling.

You will need calipers to VERIFY what you are doing.

Using equipment is going to require that you educate yourself to a certain degree.

That means alot of reading and practice...or finding someone that will show you how it's done....and then practice.




.

[NatetheGr8]

Seriously...your gonna have to look up the model number online and see what it takes....or post pics or give us a model number.

Your gonna have to go on the websites suggested and educate yourself a little on tooling types, and research in threads or on the web what others are using for tooling.

You will need calipers to VERIFY what you are doing.

Using equipment is going to require that you educate yourself to a certain degree.

That means alot of reading and practice...or finding someone that will show you how it's done....and then practice.




.

Thanks and here's the mill.
Mini mill: http://m.harborfreight.com/two-speed...not%20provided

Also I'm currently in the process of purchasing the items everyone have told me just can't find the collets at a good price. Other than that could I do the proper measurement of depth to the FCG of the lower with just the calipers, because what I assuming the digital read outs are pretty much to make the adventure easier, am I right?

[Germz]

I would return that mill, save yourself a few hundred dollars and go the router / jig route in order to complete an 80% lower.

80% arms and Modulus arms make good router based jigs.

[edgerly779]

Reliable tool in Irwindale has lots of tooling. I got my big mill vise from them and they had a lot of collets. Also do not use a router if you have a mill. No comparison. Randall should chime in on this. I bought a mill to do lowers and support my other shop equipment. I just built a 24" sheet metal foot brake and am going to make a vertical press brake. I have done 1911 frames from TM. Sevral 80% ars.

[bohoki]

ive done so many bare handed on a drill press i cant imagine the luxury of actually having handwheels much less digital indicators

i would just rough it in with marks then use a hammer to get the final width fit also an upper to make sure it fits in the back

[klewan]

That's a neat little machine; just what you need for an 80%. It's R8 collets, cheapest and most available. Get some scrap aluminum at ALCO in Oakland or off the net and practice on that. Once you can duplicate the dimensions off the print, then start on your 80s.

I would of killed for a machine like that 50 years ago at that price point. I did everything with a 1/4" drill motor, files, and a hacksaw....

[NatetheGr8]

That's a neat little machine; just what you need for an 80%. It's R8 collets, cheapest and most available. Get some scrap aluminum at ALCO in Oakland or off the net and practice on that. Once you can duplicate the dimensions off the print, then start on your 80s.

I would of killed for a machine like that 50 years ago at that price point. I did everything with a 1/4" drill motor, files, and a hacksaw....

Thanks a lot, what do you think about the vise and jig/tool combo on the first post? The endmills come in 3/8" and 1/4" so all I need is a 3/8" collet and 1/4" collet right? They also include some drill bit that will go with the drill chuck that the min came with. As for ALCO I'll definetly give that a try sound like a very good idea. Thanks for the great advice.