Would a mini mill work for this project?

[wdfwguy]

I have a couple of projects that I'd like to take on, and they require some aluminium milling. I've checked with some local shops, but after getting some quotes I'm considering trying it myself. I have zero machining experience and I'd have to buy a mini mill and any tooling from scratch.

Just as an example, I need to mill slots in 1"×2.5" aluminium bars. The slots are .5" wide and .25" deep. I'll attach a photo below as an example.

Just wondering if one the Sieg X1 versions would work for a project like this, and how difficult if it might be to get up and running...

 

[AngryBeaver]

I have a grizzly mini table top mill. It'll do it, just not fast.

 

[txvwnut]

Since it’s aluminum and just a straight flat run you could do it with a hand held router or a router table setup if you happen to have either of those.

 

[NC Rick]

I think a good jig for a router is a pretty good idea. A jig on a table saw maybe too. How accurate do the slots need to be? Owning your own milling machine seems like a good way to go.

 

[Jason280]

Hell, you could do it with a radial arm saw...trick is keeping everything square

 

[wdfwguy]

I have a grizzly mini table top mill. It'll do it, just not fast.

Hmm, how slow or fast are we talking?

 

[jimreed2160]

Mini mills require light passes and this project will take many trips. It gets tedious. Also helps if you hog out waste before hand. For your project I might use a non ferrous blade in a table saw. Depends on how clean everything needs to be.

 

[larry_g]

Hmm, how slow or fast are we talking?

http://faculty.etsu.edu/hemphill/entc3710/nc-prog/nc-03-05.htm

Google this, " metal removal rate horsepower " and you will come up with a few calculators. The MMR is a factor of HP and material. So the more HP you have in your mill the faster the job can go.

lg
no neat sig line

 

[astroracer]

A router would do those cuts very easily. I have used mine several times to cut out odd shapes with templates. Get yourself a speed controller as I found it worked better to dial in the RPM's to eliminate galling. A few test cuts will be required to get the speed and feed rate set.
Mark

 

[wdfwguy]

The router table is an interesting idea. Definitely less cost up front.

I'm just trying to gauge if it's worth trying to do myself at all. I don't have a sense if it's going to take 2 minutes to mill a slot, 5, 15, 30?

 

[gorilla]

The part that you left out of your question is what results do you do you expect? Do you need to hold a size tolerance, a surface finish requirement any form of geometrical tolerance? You can make those slots with a table saw or a router but the surface Finnish will look like **** and it will be hard to hold to size. You can do it with a mini mill but it will be slow. A mill drill might be a better choice and be more useful on future projects.

 

[theoldwizard1]

Mini mills get expensive FAST. Out of the box you need to spend time "tramming" it in. This can take quite a bit of time. A good vice, measuring devices, tooling, etc, etc add up fast.

 

[larry_g]

The router table is an interesting idea. Definitely less cost up front.

I'm just trying to gauge if it's worth trying to do myself at all. I don't have a sense if it's going to take 2 minutes to mill a slot, 5, 15, 30?

Bring it over and we can set it up in the HZ mill and cut a few at a time.

lg
no neat sig line

 

[wdfwguy]

The part that you left out of your question is what results do you do you expect? Do you need to hold a size tolerance, a surface finish requirement any form of geometrical tolerance? You can make those slots with a table saw or a router but the surface Finnish will look like **** and it will be hard to hold to size. You can do it with a mini mill but it will be slow. A mill drill might be a better choice and be more useful on future projects.

For instance, the example in the photo, the tolerances aren't terribly important. If the slots are .48 or .45, it wouldn't make a huge difference. But I'd like to use it for other projects with tighter tolerances.

But the finish looking like **** isn't really an option.

And if I'm correctly reading the metal removal calculator above, it looks like cutting a .5 x .25 slot in aluminum with a 4/5hp mill, the feed rate is 53 ipm. Which is much faster than I expected.