Which metalworking mill have you got?

[apelly]

I was over here where rstofer mentioned his home CNCed mill from Grizzly. I want one. I'm pretty sure we all want one. Can't really afford one right now, even though the cheapies are pretty bloody cheap these days. Then there's the tooling. By the time you've got enough to do anything more interesting that cut a 1/2" slot you're out of pocket double what the mill cost.

It seems like the sane thing to do is to buy a second hand one from a dead guy with all the tooling and accessories.

What are you guys using? Are you happy with it? How did you get hold of it? What's the best strategy for getting hold of tooling? What do you use it for? Got any pics?

Edit:
I read the attention newbies sticky which reminded me how to search properly. Found these interesting threads:
https://www.eevblog.com/forum/manufacture/cnc-router-for-pcbs-and-metal-work/
https://www.eevblog.com/forum/reviews/cnc-mill/
https://www.eevblog.com/forum/reviews/bench-sized-milling-machine/

[Corporate666]

I have a Brother Speedio but that's a whole different ballgame.

I did start out with a Grizzly (G1007 I believe) that I converted to CNC, then a Bridgeport that I upgraded to a new control, then through various machines until what I have now.

You're right - the machine will end up being the minority of the cost.  Well, it depends... more correctly, you will spend a couple of thousand on tooling just to get started with the bare minimum, (vise, calipers, tool holders, micrometer, endmills, dial indicator, coaxial indicator, gauge blocks).  And there's TONS of other stuff you will need/want in short order.  Parallels, gauge pin sets, quality drill sets, drill chucks, tapping holders, boring head, inserted facemill, carbide inserts, granite surface plate, height gauge, set of quality taps.  Not to mention cutting fluids (tapping fluid, way oil, coolant, a mister) and so much more.  I bet I have spent well over $100k on all the accessories that go along with the machines, and I don't even have a very well equipped shop.

I think there is absolutely zero economy in converting a machine to CNC.  It will always be more expensive than just buying an existing machine.

If you want to do "real" CNC work, you need to buy a real machine.  I would forget anything from Grizzly because anything that's not designed to be a CNC machine just won't hold good tolerances, and CNC machining is all about rigidity, tolerances and repeatability.  You're MUCH better off getting a used machine that was CNC from the start.  Personally I think a machine without a tool changer and enclosure is *severely* limited in use, but others may disagree (they'd be wrong  ).  Not sure what's common in Oz, but there are plenty of machines that were CNC from the factory that are essentially Bridgeport clones.  They are open machines though, without toolchangers.  The next step up would be something like a Tormach or equivalent.  The next step up from there (the level I would start at) would be a real VMC.  You can get used mini VMC for perhaps $5k if you look around.  Sure, it's a lot more than a $2k Grizzly that some guy slapped steppers on, but it's the difference between a JBC pencil soldering station and a cigarette lighter for soldering work.

Go to estate sales, machine tool auctions, look in the newspaper classifieds and so on.  Tooling sells for a fraction of what it cost new.  And any machine you buy should come with some.


EDIT:

Forgot to mention - if you don't have the space for a small VMC (they are smaller space needed than a Bridgeport, however - look at something like a Leadwell MCV-0)... then look at the CNC products from Sherline.

[ChunkyPastaSauce]

I have a 96 Fryer MB-14 stilling in the garage, but haven't fired it up.


Right now i'm using a tormach at a maker space, toy compared to others but functional and decent results if you go slow, also a Bridgeport.

[Muttley Snickers]

I am currently drooling like a mongrel dog......

Very impressive machine indeed......

[Brumby]

I'm just admiring.

Can't justify thinking any further than that.

[ChunkyPastaSauce]

I am currently drooling like a mongrel dog......

Very impressive machine indeed......

If it works     Mine is a lot more used than the one in the video. But if it works with much issue, it should be a good machine. To me it looks to be built much sturdier than many other machines in its form factor.

[Andy Watson]

I have Dore-westbury Mk2 (http://www.lathes.co.uk/dore-westbury-2), or to be more accurate, I have the parts that require some finishing to make the DW2!   - one day.

[mathsquid]

I've got a proxxon mf70 that I converted to CNC.  I mostly use it for precision drilling, but I have used it to mill a few simple single-sided boards and a few other things.  It's really easy to do a CNC conversion, but I probably wouldn't buy it again.  It is *really* small.

I also have an X1 from Little Machine Shop. http://littlemachineshop.com/products/product_view.php?ProductID=4700&category=1387807683, and I really like it.  I haven't converted it to CNC, and I probably won't, but it's a nice small machine.  I have some unboxing videos on my blog.  I got the unit with the MT2 spindle and bought an MT2 to ER-20 adapter for it.

I also have a old sherline lathe that I got a really good deal on through ebay.  I bought an MT1 to ER20 adapter for it, so I can use the same set of collets on my mill and lathe.  I really like the sherline, though I run into its size limitation more often than I'd like.

[thommo]

Hi Guys,
I've been having a sniff around for about the last 6 mths for something that has potential to integrate a 5th axis [from its original design and SW].
Do any of you have any experience with, or know much about, the Hass line of VMCs from the USA?
In particular I've been looking at their MiniMill2 series.

[ChunkyPastaSauce]

Hi Guys,
I've been having a sniff around for about the last 6 mths for something that has potential to integrate a 5th axis [from its original design and SW].
Do any of you have any experience with, or know much about, the Hass line of VMCs from the USA?
In particular I've been looking at their MiniMill2 series.

Try asking rx8pilot

[kripton2035]

I have a sieg SX2 mini mill with brushless motor and I really like it, it's perfect for the small precision work I do
I added igaging dro because I don't like counting turns of wheels all the times...
and I'm adding now a powerfeed because I'm fed up turning the X wheel all the time...!
I will not turn it into cnc it has too much backslash and I dont want to change all the bearings, simply it's not a mill for cnc
may be I will add an Y motor, and do some small 2d cnc with it but not further

I also bought a sieg SC3 mini lathe and like it but it is quite too light for my use
and the upper model was too expensive for me

[H.O]

I've got a small CNC bed type mill that I built >10 years ago and a larger CNC converted Abene VHF-3 knee mill which is another of those never ending projects....







(Geez, embedding images in a post here is cumbersome)

[Fred27]

I've got a proxxon mf70 that I converted to CNC.  I mostly use it for precision drilling, but I have used it to mill a few simple single-sided boards and a few other things.  It's really easy to do a CNC conversion, but I probably wouldn't buy it again.  It is *really* small.

I started with a converted MF70. A great but tiny mill. I recently moved up to a CNC6040 - and replaced the junk electronics of course.

If you're tempted by CNC then beware! It's very addictive stuff.

[mikeselectricstuff]

I currently have a CNC3040, mostly used for PCB milling, and it's _just_ about OK, the main issue being lack of rigidity which causes tool chatter.
I'm only really interested in plastic  (e.g. corian,delrin), FR4 and maybe ali, and only small pieces (A4 size max).
Is there anything out there that's oriented towards smaller, lightweight stuff, but that has good rigidity to get accurate, repeatable cuts?

[Corporate666]

Hi Guys,
I've been having a sniff around for about the last 6 mths for something that has potential to integrate a 5th axis [from its original design and SW].
Do any of you have any experience with, or know much about, the Hass line of VMCs from the USA?
In particular I've been looking at their MiniMill2 series.

The minimills are good machines... what are you intending to do with it?  I wouldn't buy one if you intend to cut 4140 mostly, but for aluminum and plastic and the like, they would be ideal.  The super mini mill isn't much more $$ and is quite a bit better machine, IMO.

Keep in mind the loss of Z travel with a 5th axis.  There are many machines that will take a 5th axis but reduce your Z so much that you wind up pulling your hair our searching for short tool holders and such. 

[DaveW]

I currently have a CNC3040, mostly used for PCB milling, and it's _just_ about OK, the main issue being lack of rigidity which causes tool chatter.
I'm only really interested in plastic  (e.g. corian,delrin), FR4 and maybe ali, and only small pieces (A4 size max).
Is there anything out there that's oriented towards smaller, lightweight stuff, but that has good rigidity to get accurate, repeatable cuts?

http://www.ukcnc.info/forums/cncmachines.php

I've got one of these at work and it's perfect for the crossover between milling and routing. Full ball screws and solid construction make it really accurate and it'll cut aluminium with no problem; I use it making front panels and suchlike, and have also made some enclosures from aluminium solid, although this does take a while.

[ServoKit]

I'm using one of those China CNCs ("6040") with an 800W spindle. I use it to mill carbon fiber, 5083 aluminum and plywood. The machine works ok considering the price (1500 EUR w/ spindle incl. taxes & shipping). 800W is on the lower end for machining metal parts, thinking of upgrading to 1500W. Attachment shows typical parts I made with the machine.

Regards, Axel

[Ichan]

I currently have a CNC3040, mostly used for PCB milling, and it's _just_ about OK, the main issue being lack of rigidity which causes tool chatter.
I'm only really interested in plastic  (e.g. corian,delrin), FR4 and maybe ali, and only small pieces (A4 size max).
Is there anything out there that's oriented towards smaller, lightweight stuff, but that has good rigidity to get accurate, repeatable cuts?

Lightweight and Rigidity usually not on the same direction, video below is what i use and sell in here.



Steel body, the 20x30 cm machine has a weight about 50 KG - not a lightweight, but a very rigid machine.

They still make this 20x30 machine, but not displayed anymore on their website as they now have a more attractive 30x30 machine:

http://www.wklaser.com/index.php?m=content&c=index&f=show&catid=125&l=2&id=343

-ichan

[ServoKit]

I've visited Intermodellbau 2016 yesterday. Here's an overview of the available CNC mills and routers with plenty of pics:

http://servokit.com/blog/2016/04/24/cnc-mills-and-routers-on-intermodellbau-2016/

Regards, Axel

[CatalinaWOW]

Each region will be different, but here in the Western US unless you get lucky there are several choices at prices which might appeal to hobbiests and small shops, all with their own drawbacks.

1.  Non-CNC Bridgeports.  Good mills and they often come on the market for well under $1000 dollars.  Lots of work to convert to CNC, take up lots of room and usually are set up for 3-phase power.  Good choice if machining and electronics are both hobbies and you have lots of room and existing machining capability.

2.  Old used CNC mills.  Two big drawbacks are that they usually use obsolete programming languages and are still priced pretty high for hobby purposes.  Size and power requirements are also issues.

3.  Grizzly family mills converted to CNC.  Prices after conversion to CNC are about the same as converted Bridgeport, but low space and standard power requirements.  Accepts g-code which can either be generated by hand or by a large number of current software products.  Yes they are speed and power limited, and also not the apex of accuracy, but they can do the work that many of use in electronics want to do.  No tool changing or other fancy features.  I have one inherited from a son who moved on to other things.

4.  Tabletop mini-mills.  Lowest cost approach.  Limited to small light work, but still adequate for lots of things like cutting connector cutouts in project boxes or drilling PWBs.

So there are no ideal solutions.  The direction depends on what you are willing to pay in space, electrical support and cost and what you need in terms of part size, speed, accuracy and how much automation you need (tools changes and the like)

[Alexei.Polkhanov]

I did some machining for hobby over past few years, almost after 15 year break, and this is notes from my experience:

- No two pieces of (affordable) equipment will work on plastics, PCB routing, small work pieces and large or medium size metal work. Spindle speeds that you need for quality results in first case are in range of 8000-25000 RPM. These machines take only small tool sizes and you will need to think about types of mounts and collets that will work at these speeds. Besides plastics and wood they are not good for anything else.

- For anything serious with aluminium, steal, bronze, brass, stainless steal you need a mill which has as much metal on it as you can afford. I would get a solid, heaviest cast iron body machine like Bridgeport with good bearings and good DRO (not CNC). DRO gives enough convenience and precision for most of one-off work. 2.5 HP motor minimum. If you buy used check with dial indicators if it runs true and then test again 

- Again speaking of DRO and CNC. You cannot make complex things like boat propellers with DRO, but for almost anything else there are things like boring heads, circular vises, dividers...  With these you can make a hole for press fit bearing and be +- 0.05 mm true on center. CNC, unless it is closed loop one (expensive) not going to be useful here.

- All milling tools are designed for one type of chuck - R8, MT3, MT2 etc. So you pretty much stuck with it. It would suck if you decide to get another mill which takes R8 when you have to replace/swap thousands of $$$ worth of mills and collets and tool holders that don't fit anymore.

- end mills, face mills, fly cutters, slot mills ... If you have none, expect to buy $20-50 of tooling for every new job.

- You need vise and other work holding stuff. Good machinist wise can cost from $200 to $2500 and more. You need set of dial indicators, edge finders. Even with DRO you still need to find where all the 0s are. You most likely will work on things that are done, like machining new mount on $500 stepper mount - you don't want to screw that one up 

- Also you need a pump for cooling, nozzles. Perhaps you can use shop air with mist sometimes.

Here in North America in terms of good used equipment I am pretty much stuck with machines like Bridgeport in your area choices maybe different. Think about the delivery of this 2 ton thing!

Tooling can cost as much as machine itself.

Check this Youtube channels:
https://www.youtube.com/user/Abom79
https://www.youtube.com/user/oxtoolco
https://www.youtube.com/c/shadonhkw/videos

[ChunkyPastaSauce]

I currently have a CNC3040, mostly used for PCB milling, and it's _just_ about OK, the main issue being lack of rigidity which causes tool chatter.
I'm only really interested in plastic  (e.g. corian,delrin), FR4 and maybe ali, and only small pieces (A4 size max).
Is there anything out there that's oriented towards smaller, lightweight stuff, but that has good rigidity to get accurate, repeatable cuts?

Take a look at Tormach 440, base machine is ~5k, controller is ~700
Also maybe a used Emco PC Mills, they are in the 2.5-5k range on ebay

[H.O]

- Again speaking of DRO and CNC. You cannot make complex things like boat propellers with DRO, but for almost anything else there are things like boring heads, circular vises, dividers...  With these you can make a hole for press fit bearing and be +- 0.05 mm true on center. CNC, unless it is closed loop one (expensive) not going to be useful here.

Great post, I agree with most of what say except the above. Closed loop is great, and for best accurcy you want the position feedback from the linear scales on the machine axis and not from the motor but a dialed in open loop, stepper driven machine are perfectly capable of putting a hole well within +/-0.05mm (that's not even very accurate IMHO) and do circular bores for bearings etc.

You may to "sneak up on it" by taking a couple of finish passes and dialing in the tool offset but you need to do that with a boringhead as well. And once you've dialed in the finish pass you can do it over and over again and get the same result - until the tool wears but that happens whether or not it's CNC. I'd say that for accurate circular boring you do need screws with "zero" backlash though, relying on software for backlash compensation generally doesn't work that well and you end up with marks at the quadrant-points where the backlash is taken up.

You can see my DIY machine referenced above, with open loop stepper motors, doing a circular bore for a bearing here: (geez 8 years ago, time flies...)


And this is a rather flimsy machine compared to a real metal working milling machine like a Bridgeport or my Abene.

Finally, although doing complex shapes are perfectly doable on a manual machine you do need a lot of special tooling and other gear (and the knowledge to setup and use it properly).  With a CNC it's a lot easier, doing cutouts for odd shaped connectors, fan grills etc.

[Tepe]

I've visited Intermodellbau 2016 yesterday. Here's an overview of the available CNC mills and routers with plenty of pics:

http://servokit.com/blog/2016/04/24/cnc-mills-and-routers-on-intermodellbau-2016/

Regards, Axel

Unauthorized access. Logging IP address: xxx.xxx.xxx.xxx

[Alexei.Polkhanov]

- Again speaking of DRO and CNC. You cannot make complex things like boat propellers with DRO, but for almost anything else there are things like boring heads, circular vises, dividers...  With these you can make a hole for press fit bearing and be +- 0.05 mm true on center. CNC, unless it is closed loop one (expensive) not going to be useful here.

Great post, I agree with most of what say except the above. Closed loop is great, and for best accurcy you want the position feedback from the linear scales on the machine axis and not from the motor but a dialed in open loop, stepper driven machine are perfectly capable of putting a hole well within +/-0.05mm (that's not even very accurate IMHO) and do circular bores for bearings etc.

I am still very skeptical. Stepper may not be skipping if it is not overloaded so it is OK but every machine has things like backlash etc. Video shows that bearing fits in but I would be  convinced if someone makes 3 (repeatability!) circular cuts like that and checks them with co-axial dial indicator around the perimeter. If 30mm hole is circular within +-1 or +-2 mill (or 0.05mm) I would be happy.