80% lower construction...the proper way?

[Espire]

Hello all.

So I decided to pick up a few lower 80% receivers. Bought the template, and orders the bits. I'm still missing the largest component.


So here is my question.

It seems for a decent drill press, I'm going to spend around the $500 mark (I know I can get one's cheaper, but want to buy something that I buy once, and not have to worry about it for several years; and I need it to be floor standing due to space).
The Grizzly mini milling machine (which quite a few people seem to really like) goes for $725 shipped. I have never used a milling machine, and know their is a curve to learning it; I'm okay with that.


So, which would be my better option? And why?

Thanks in advance.

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[F2CMaDMaXX]

Unless you're planning to, or think you will get a lot more use out of it, get the cheapest (not shoddiest) version you can get.

It'll do what you want it to and if it's not used heavily, it's not going to break, if it does, it proves you do need a nicer one.

 

[Ura-Ki]

Many folks laugh, but the big drill press that Harbor Freight sells has worked out well for me for several years with out any troubles at all. The money saved on that drill press can then be used for a really good cross vice which IS a must have for doing 80% builds! IF you end up with a drill press, make sure to get one with a 1/2 inch drill chuck!!!

 

[rick benjamin]

I bought the HF mini-mill
Then the spindles
Then the bits
Then the gauges
Then more and more stuff
What's the fun in going cheap?

 

[jbett98]

Estate sales are the best deals in town. Most weeks there's a sale with a drill press in it, and there are some vintage top quality machines that you can pick up for cheap.
I paid $100.00 last year for a very nice one and it came with a whole bunch of extra's, including a mill vice that worth more then what I paid for the press.
Check out Estatesale-Finder for upcoming sales.
They show pics of what's in the sale and make sure you get in early.

https://www.google.com/url?sa=t&rct...es.php&usg=AFQjCNHscEQkVyBMvFWeX2lm3ql2Y9FLhw

 

[bolus]

which jig did you get?

with as Easy Jig you can do an 80% with a router and handheld drill. Total costs would probably be less than a good drill press.
80% Arms:Universal 80% AR-15 Easy Jig

 

[rdb241]

which jig did you get?

with as Easy Jig you can do an 80% with a router and handheld drill. Total costs would probably be less than a good drill press.
80% Arms:Universal 80% AR-15 Easy Jig

Just bought one yesterday!

 

[IronMonster]

I just bought a new 9x49 Jet knee mill with a 3hp VS head, 2 axis DRO and factory power feed on the X axis

I thought maybe it would work to do an 80% lower until I got me one of those Harbor Freight drill press everyone likes.

 

[AMProducts]

So here's a few things....

Drill presses typically are not designed for the lateral stress required for milling, this will wear the bearings out quite quickly. The other major problem is that a lot of them the chuck just slips over a jacob's taper (or something similar) which makes it really easy with all that lateral force for the chuck to just fall off, or to drill itself deeper into the material and then fall off.

I will say, if you're intent on using a drill press for this, you definitely should invest in a x-y table for the bed, and you should also make sure the table is both true to the axis of the chuck, and is also so tight it cannot vibrate itself around the support shaft.

The HFT mini-mill isn't too bad for what it is, the nice thing about it is you can make an el-cheapo DRO for it with a pair of digital calipers and some magnets/glue. The number one thing in any "mini-mill" is to avoid anything that supports the head on a round column, as the vibration of milling inevitably pushes the head off screwing up your part.

If you're just looking for something small, but don't mind spending the money Taig and Sherline both have good offerings, and also offer CNC-ready versions. they are quite a bit more expensive, and not as rigid as some of the bigger mini-mills, but if you make reasonable demands on material removal these machines will totally do it and fit on a desk.

If you're feeling plucky, you could probably also do this on a ready-made CNC router, like the shapoko.

 

[shooter777]

Go with an easy jig. It's pretty easy with a hand drill with new bits and a router. I used both a regular router and a trim router. Just make sure you check the tightness of the collet from time to time and don't try and remove too much material in one pass.