Looking at a new CNC for home (might build might buy, not sure yet)

Hey Aussie Guys,


Has anyone had any experience with CNC3D in Australia?


https://www.cnc3d.com.au


I was looking at building my own CNC and stumbled across their online store for profile rails and ball screws.


They're based on the Gold Coast.


I noticed they had some CNC kits available for home hobbyist use but I'm not sure if they will work well for nicely milling Aluminium. They do advise it will but at a very low feed rate.


One of their sales reps told me I might be better off holding out for their new Nighthawk CNC range.


apparently they use a rotating nut design rather than a rack and pinion for their full sized machines.


It looks like a beefed up version of what I was going to build haha.


What do you guys think of a spinning nut design rather than screw?


Here's their blog post


https://www.cnc3d.com.au/post/our-ne...is-coming-soon

Hi Slixxor - I'm at Murwillumbah near Gold Coast. If you want to mill aluminium then you need a mill, a router is not ideal for that sort of work. What exactly do you want to make? No problem with running nut design if its done right. This forum is full of Mill/router discussions. Happy to help. Peter

Quote:

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Originally Posted by peteeng

Hi Slixxor - I'm at Murwillumbah near Gold Coast. If you want to mill aluminium then you need a mill, a router is not ideal for that sort of work. What exactly do you want to make? No problem with running nut design if its done right. This forum is full of Mill/router discussions. Happy to help. Peter

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Thanks mate.

Although I do agree that cutting aluminum on a router is sub-optimal; I have seen people on YouTube do it and get results that were... eh... OK. The successfulness of the operation seemed to correlate with the rigidity of the machine; and taking light cuts was a requirement. Also, aluminum does vary - some of it is very easy to go thru; other grades not so much (this is as compared to hardwood - of course; compared to steel, all aluminum is like butter).

For working on aluminum, if you are going to get a mill and convert it (or perhaps even get an older VMC that has some life left in it; and modernize the control); I would look for a machine with a spindle speed on the higher end of the spectrum - you will get better surface finishes that way.

Do you have 3 phase power available to you, or just single phase? That's going to be the primary limiting factor on how big of a machine you can get; above a certain size the VFDs used to drive the spindle motor require 3 phase input (although some VFDs can be told to ignore the missing phase alarm and run anyway; and you just get a bigger VFD than the motor's KW rating would suggest).

:)

Quote:

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Originally Posted by __Britt

Although I do agree that cutting aluminum on a router is sub-optimal; I have seen people on YouTube do it and get results that were... eh... OK. The successfulness of the operation seemed to correlate with the rigidity of the machine; and taking light cuts was a requirement. Also, aluminum does vary - some of it is very easy to go thru; other grades not so much (this is as compared to hardwood - of course; compared to steel, all aluminum is like butter).

For working on aluminum, if you are going to get a mill and convert it (or perhaps even get an older VMC that has some life left in it; and modernize the control); I would look for a machine with a spindle speed on the higher end of the spectrum - you will get better surface finishes that way.

Do you have 3 phase power available to you, or just single phase? That's going to be the primary limiting factor on how big of a machine you can get; above a certain size the VFDs used to drive the spindle motor require 3 phase input (although some VFDs can be told to ignore the missing phase alarm and run anyway; and you just get a bigger VFD than the motor's KW rating would suggest).

:)

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Thanks Britt, food for thought. :)

I cut ali on my el cheapo OmioCNC router reasonably regularly without a lot of drama, but with a few caveats:
- it's slow feeds and small tools with one or two flutes - 6mm running at maybe 2000mm/min on a 3hp spindle.
- carbide tooling rocks but use uncoated - a sharp edge is more important than pretty much anything a coating will offer.
- lubricate or die: I use a 20% metho, 80% water mix (inspired by the Datron machines) in a mister to both keep the cutters lubricated and blast chips out of the way to prevent re-cutting chips, which will lead to welding and busted cutters. Note: this means cardboard, sorry, wooden frame machines are no bueno. And allow for some good air supply in your budget, too, if you don't already have a compressor.
- routers aren't typically built to hold submicron tolerances and they flex when you load 'em up. So go in expecting no better than about 0.1mm tolerances and cut light or you're going to be unhappy with the results.
- usual stuff about noise, neighbours etc. Cutting ali can get noisy.

Working with this router and then going to my last gig where they had stuff like Bridgeports and big Haas machines was kinda disheartening - proper mills hold much better tolerance, cut faster and cleaner and the whole experience is a lot less janky.

But, unlike the US, it's fairly rare to be able to pick up a second hand mill here in anything like decent condition. You could convert something like a Hafco or Optimum machine with a decent table size for maybe $10k all up and that would do pretty well, I think. Or - like me - just use the router and work around its limitations.

I'm in Melbourne and run 3 optimum machines.. all converted to CNC. A BF-46, BF-30, and turner 280. All have cost me thousands in time, effort and money... and was it worth it... no way!!!

Each machine has its issues and has taken years to sort. The BF-30 has been with me the longest and runs linear scales for closed loop feedback and has had the gearbox replaced with a direct drive spindle allowing me to cut at 6000rpm. It's had so many hours invested in it... and been pulled apart more times than I care to remember. It's cut so much aluminium it's on it's second set of C4 ball screws, but funny enough the dovetails seem fine.

There is another Melbourne guy on this site who is currently putting his BF-46 on linear rails and has bored out the head for fitment of a 10000+ rpm spindle. It's taking this to the extreme, but I still feel no matter what you do with a drill mill, your never going to have an Optimum F4 or a Syil X7. Both are running at $AUD30K delived. But you can get into a Syil X5 for $AUD12K which is good value.

If you're really serious about getting something decent under 20K then I know a guy who can import it for you. If it's really good I might get one myself ;-)

Well you learn something every day. Thanks, FastFarmer :)

Better off waiting for an old bridgy to turn up and re-build the controls, then? Or scrimp and save for a little Haas machine? I watched the growing drama of the skyfire machines as imports and there's another thread here on an import from lcvette that started off really promising but kinda went sour. My own experience with the Swissmak 7 axis machine build saga hasn't been great but I'm still holding some hope of it being completed one day.

After seeing all these nightmares unfold and your comments around retro-fitting the Hafco stuff? I think, were I to suddenly have a need to accurately and quickly cut metal, I'd be sucking it up to buy a machine from a known brand.

The Adept CIM Centre in Qld sell second-hand Adept 2-axis machines. Separate mill and lathe spindles.
http://www.adeptcimcentre.com.au/
They are not large, but they are good. ($30k new I think.)

These machines were supplied to NSW high schools so kids could learn CNC - but there were no teachers, so few of the machines got past their installation checkout. The machines are ULTRA-rugged - to handle student crashes. They do not flex! Mine has a single step resolution of 0.8 um, is easily repeatable to a few ums, and I machine ANYthing on it: plastic, aluminium, steel, titanium, even basalt (Mohr hardness 9).


W7, Mach3 .062, ESS, Homann BoBs, Gecko drivers. MY front panel stuff though.

I can recommend them.

Cheers
Roger

Hi Roger - link doesn't work? Peter

Neither it does.
It seems they have switched to selling 3D printers into the Edu market. They may have run out of CNC machines to refurbish.

Cheers
Roger

If you buy or build a cnc router with proper extrusions then it should have no problem milling aluminium. Mine eats through aluminium and i have also milled steel plates a couple of times no issue.