[oxi]

Hello,

I'll try to keep this short, but I'm bad at that:

First, my questions:

1. I've heard that some cheap aluminum CNC can mill steel using a very small depth and many passes. True or not?
2. What can I do? You might want to read next a little, probably the smaller paragraph.

I've been working on building a CNC mill since May 2013 and it's VERY far from completion.
I spent 5 months working basically full time except sleeps to design the machine on Autocad.
I tried to build it as I planned and bought 500Kg of steel bars (yeah, you read it well) and as many cheap tools as I needed and could afford.
I ended up giving up on cutting the steel bars with my jigsaw, I made a better job with my hand saw but it took forever, this is 1cm thick steel plate. I got a cheap angle grinder, I gave up on that soon because it was damn scary, I use it occasionally for other stuff. I ended up buying a plasma cutter in an auction. Very rough cuts, but good for most of my parts, who cares.
I then had to buy a vertical drill, cause it was nearly impossible to make straight holes by hand. And finally after wasting so much time making holes and threading them to bolt them,(I designed it all to be totally modular) I decided I couldn't waste any more time and bought a cheap welder and learnt to weld (still learning).
And my last decision was to leave the plates aside and try to work with hollow tubes, but it's not working out well for me.
I can't work fast, I can't make the holes straight enough because I can't clamp things properly, I can't weld any good and the pieces bent a lot, and I can't make straight cuts with the grinding wheel for some reason nor the exact length.
I have developed some sort of anxiety attacks and gone to the ER several times ever since I started designing this thing.
I really feel like I'm wasting my time and like I've had enough, but I don't want to quit just yet. I need to get this done. I wanted to make this myself to save some money and I'm spending a lot more I could have spent on a good router. I wanted to build a machine good enough to mill steel and with a long z axis, and I could have bought one like that with all the money i've spent by now counting the monthly fee I'm paying for storage.

So what can I do? For the moment I just want to work with rather thin samples of wood or alum, but eventually I'll want to be able to machine steel with rather thick profiles. If at least I could know for sure that those cheap alum routers can mill steel, I could start working on my production and then try to machine the parts for my diy CNC. But I'm not sure what to do. I don't need more mistakes nor wastes of time. What should I do? 1. Get a cheap CNC router (but I need to be able to cut the steel parts for my diy mill with it) 2. Get a better CNC mill (not over 10k. I'd rather not do this for I might not be able to make it through the year) 3. prevail... (but the end of the tunnel is out of sight)

Thank you

[ger21]

I wanted to build a machine good enough to mill steel and with a long z axis

That's not going to happen with the tools and equipment you have.

1. I've heard that some cheap aluminum CNC can mill steel using a very small depth and many passes. True or not?

Yes and no. I've seen routers cut small pieces of steel. But I've not seen any actually making steel parts.
Router spindles won't last long cutting steel, and tools won't last long making small, light passes.

If you need to make steel parts, then you need a big, heavy, and rigid machine. An old used machine would probably be the best thing if you're on a budget.

From what you've said, I can't recommend continuing on the path you've been on.
If you need a machine to make products, then I would buy the appropriate machines that you need. As you've already found out, it will be cheaper and faster in the long run.

[louieatienza]

You can find old mills for cheap, even 9 x 49 or 10 x 54 table. Use the mill to build motor mounts and CNC the mill. Use the steel plate you have for stepper mounts.

[kdoney]

You've given it a fair try. Forget it. Go to work for someone and earn enough money to buy the machine you can't build. You don't have the nature or nurture to do this kind of work. What did you last do that made you happy?

[oxi]

First of all, ladies and gentlemen, thank you all for your help.

Sure enough my experience has been a slap of reality. But I'm not sure it was big enough a slap yet.

So based on your valuable input I boiled my options down to buying either a cheap router or an old mill.

I looked through some old mills and I'm rather reluctant to get one for the aforementioned reasons (money) and because in case things come bad I won't be able to store such a beast anywhere (unfortunately I don't own a garage) until I can sell it (which I doubt).

So I'm contemplating getting a cheap aluminum router, THEN machine some of my diy parts in aluminum, build my diy, and THEN with the diy machine, try to machine some parts of my diy in steel. The idea is that if anything goes bad while machining steel, I'll be able to replace the parts (spindle, steppers, etc) on my diy, while I'll still be able to use the cheap machine to produce.

As another option I'd also consider buying a manual mill to work my diy parts, but I doubt these are any much cheaper than CNCs, and won't let me produce...

Please tell me what you think, I appreciate your input. Thank you.

[Devastator]

If your main requirement is to mill steel, get a manual mill and convert to CNC.

Yes, they are beasts, as is any mill designed for steel. Because they have to be to do it correctly.

[ger21]

(chair)

Is that hard enough?

If you need to mill steel, you need a mill, and not a DIY mill.

Any other path you take will lead to a miserable ending.

[Devastator]

I have developed some sort of anxiety attacks and gone to the ER several times ever since I started designing this thing.

You are trying to learn too many trades all at the same time. Many people spend half a lifetime as steel fabricators to do what you are trying to accomplish.

[mcphill]

STOP even contemplating machining steel with a router or a machine that uses aluminum in ANY of its support structure. If you want to machine steel parts, you need a SOLID, heavy machine (cast iron). If those parts are small (tennis ball or smaller), you may be OK with a smaller manual mill, but you want to regularly machine parts larger than a tennis ball, you will need $6k+ to do it reasonably well at all. Stop wasting time and money trying to convince yourself otherwise!

[cnewb]

OXIE,

I too, can feel your pain. Five years ago I decided to get a CNC router to supplement my manual lathe and manual 3-axis mill activities.
I surveyed what was available at the time, but could not find what I wanted for under $15K. So I decided to build my own,
Conceived a design, bought a bunch of parts, machined a lot of parts, made numerous "design" changes, yada, yada.yada.
Finally I realized, I don't want to build a router, I want to use a router to build stuff I was really interested in.
I re-evaluated my needs and searched again.

Then, 2 years ago, out of the blue, the perfect machine for me jumped off a website. A little due diligence convinced me to take a chance and order it ( from China yet )
I spent right at $2500 US, and had a fully functional machine in my shop in about 10 days. FED EX delivery $205.

It is not a production rated machine, but perfect for my engineering prototype activities. I have cut virtually every materIal known to man. No Titanium yet.
Paper, Vinyl using a draw knife. Plastics .... all types. Steel ... .062 inch automotive brackets. ( a real challenge but I did it )
Pocketing of Corian, Delrin, Aluminum, Wood, even a small job modifying a cast iron part.

The secret to all that is correct cutter for the job and the proper speeds and feeds setup.

I had an old XP computer, ACAD Lite 1998, then purchased Vectric Cut 2d, and MACH 3 ........ same configuration is running as I write today.

Learning curve ? Yes, but there are lots of people willing to help out. Just look at some of the replies to your query.

Since 90 % of my work is 2D projects, this setup works fine. I have cut parts using V-Carve, Cut3d, even a couple of parts designed with ASPIRE, so 3d stuff is ok.

I purchased a small 3D printer last summer, works ok, Not a DIY but a turn key ....... Learning curve principles still apply.

Oh sure, I really wanted the full sheet ( 48 X 96 inch work table ) 3 HP spindle, 12 position ATC; but it costs $49,000. Do I need it ? Not NO but HELL NO!

Just my 2 cents worth, via my experience with your problem.

Good Luck !!

[oxi]

Hey people, I couldn't have dreamed of a better support response. I really appreciate your help and expertise
I wish now I had sought your help before...

I didn't make myself clear, I want to be able to machine steel eventually but just occasionally.

I think the best is to get a cheap aluminum router for now.

At a later stage I might get a cheap small manual mill. They're not nearly as expensive as CNCs actually, and with that at hand I could try to convert it to a CNC as suggested.

I'll be sad to leave my DIY behind, but... I think it's time, I'm ready.

Thank you again!

:cheers:

[oxi]

Then, 2 years ago, out of the blue, the perfect machine for me jumped off a website.

cnewb: Can you provide a link to your machine? Is this a 6040? What brand? The problem I see with Chinese products is there are many clones and it's difficult to find a brand you can trust.

[ger21]

I didn't make myself clear, I want to be able to machine steel eventually but just occasionally.

You'd be better off to pay someone else to do it for you.

[mcphill]

You'd be better off to pay someone else to do it for you.

I want to average over 30 mpg, and only occasionally enter an F1 race. Kind of an appropriate analogy ; )

[oxi]

Buddies can you take a look at this one and point the drawbacks? 6040 4 Ejes CNC M

What I like:
sends from my territory, so no import taxes and cheap shipping costs
pump and 4th axis included
all ballscrews 1605
takes up to 100mm high pieces

limit switches not included but I got some and seems like the controller board can use them
I don't know how many degrees per step, but looking at the overall precision I guess they're greater than 1.8deg?

Can I use cutting fluid with the water pump?
How is the spindle speed set? through g-code?
Will these motors and spindle suffice to cut aluminum?

I remember I saw a much bigger router back then that sold for around 5k. I think it used NEMA 34 motors, and probably a much more powerful spindle. I wonder if I should be looking at that instead if I intend to cut aluminum.

:cheers:

[mcphill]

Don't buy an engraving machine if you want a router, don't buy a router if you want a mill. If you buy a mill, you can route and engrave (though not as efficiently as a dedicated router or engraver). Don't buy a mill if you want a laser cutter. Don't buy a laser cutter if you want a plasma cutter. Don't buy a plasma cutter if you want a waterjet...

Let's reboot this discussion...

List that type of jobs you want to do, types and thickness of materials, time you can spend on each job (do you have to hog out material or can you take many passes), bed size you will need, budget you have access to. Bucket "similar job types" in to an overall % (I will be cutting wood objects the size of a baseball 50%, flat wood objects 4" x 6" x 1" or smaller 25%, aluminum sheet 20%, cast iron and steel 4% and unobtanium 1% of the time).

Once we understand WHAT you want to do with the machine, we may be able to make reasonable attempts at suggesting what TYPE of machine would allow to to achieve the majority of your goals. Almost certainly you wan't be able to do everything you want with one machine.

All we have now is one off ideas of machines you see, one off ideas of what you want to do, and the 2 categories do NOT match each other at all! Help us to help you!

[oxi]

Thank you mcphill

Okay, I didn't have an idea this was so important. I thought the difference between a router and mill was just Z axis depth and stiffness, and power I guess. I didn't even think there was any difference between a router and an engraver... I wanted a one fits all but you made it apparent there's nothing (cheap) like that. Thank you.

Well bearing that in mind, this would be my (hopefully realistic enough) guesstimate:

I can take many passes, time's not that important as long as things get done.
A 60x40cm(24x16in) bed will do, I could go smaller but I'd rather not.
I'd feel comfortable spending $5k, I could VERY uncomfortably go up to $10k.

baseball size wood: 40%
3/16" thick aluminum sheet: 40%
3/16" thick wood sheet: 15%
baseball size aluminum: 5%

And let's just forget about steel for the time being.

:cheers:

[ger21]

3/16" thick aluminum sheet: 40%

What size sheet? (width and length)

What grades of aluminum?

[louieatienza]

I still think a mill would suit you best. I've seen guy attach outrigger spindles for high speed work as well. A G0704 tupe mill would give you about an 17" x 8" x 10" work area, anf you'll have room on each side to mount a rotary axis and tailstock. Shouldn't be too horrendous to move either.

[victorofga]

oxi

practically any cnc router will ENGRAVE steel.. means makes about 0.2 mm depths a very small diameter..
but this is not called milling..
and beyond this everything is just miserable..

as others tried to pointing, you need a mill...

if you buying from china, don't look for brand.. look for what they build in parts..
shop with your ""eye"" not with your ""ear""

on the zone hoss converted a grizzly to cnc..

I don't know how much it cost.. but guessing really the cheapest solution for size per price..

then you ready for virtually any material..

http://www.cnczone.com/forums/bencht...sss-g0704.html

with this you can satisfy you build it, also the outcome very much predictable..