Which machine to get / build

[GeorgeS]

Hi everyone,
This is my first post on here so appologies if I have put this in the wrong place.

I have been wanting to get a CNC for a few years but have never had the money. I have a budget of around £500 and cant decide how to use it. My options are either a pre built machine / kit like a 3040 router, build a machine from scratch, or convert my Warco WM16 mill to CNC.

I am leaning towards converting my mill as I want to be able to do some machining in aluminium, brass, and maybe steel but I dont know how much this would cost and I would like to still be able to use it like a manual machine afterwards (maybe some kind of hand wheel like on big boy machines).

Anyone with a 3040 type machine, how capable are they and how is the buing experience?

I have a lot of experience with 3D printers and CAD software (Fusion 360) but none with any machining specific software or machines other than watching videos on youtube.

Thanks

[mekanik]

Hi GeorgeS
Welcome to the forum, budget is a little sparse but don't even think about the 3040 machines in that price range, no where near rigid enough for metals.
hopefully someone with more experience will advise regarding the cost of electronics/power supplies/stepper's ect but your best option is to convert the mill.
Enjoy your stay.
Regards
Mike

[eci22]

I've got a 3040 machine and it's fine for learning on and comes in at a good price. You will not plow through aluminium but in my experience it has been fine for plastics and wood (specifically MDF and plywood). If you are only interested in working with metals then it's probably not the one to go for, if you want to work with softer materials and just learn about working with a router then it is suitable for that purpose.Good luck !

[Doddy]

Does the WM16 work-area/table suit your CNC requirement?, do you use it rarely as a manual mill? Is the spindle suited to the work that you're looking to do? If the answer to any of these is no, then look elsewhere (but you'll struggle on your budget).

I converted a SX2.7 (It's a Trigger's Broom - so little left of the original now I refuse to call it a Sieg) having got bored of spinning little wheels by hand - they can be made into reasonable bench mills with little effort. Besides, the conversion can be fun. But you'll be on the edge of your budget. Manual wheels?, you'll suffer the commutating forces of a stepper, you can get by with a MPG / electronics. To be honest, other than the quill control (which I retained) I don't miss the manual wheels at all.

The 3040 might polish a bit of steel, but probably not much else.

[JAZZCNC]

Forget the 3040 type rubbish they are only just good enough to cut MDF and can't do that correctly.!

To me with your budget your only option is to convert the Mill and even then you'll have to buy wisely. If it was me I'd do it in phases and improve it as you go along and get a better fell for CNC.
Start by using the leadscrews that are fitted and just connect steppers to them, this is simple and cheap with minimal to no impact on the manual machine.

Controller wise then It's a perfect candidate for using Linux CNC because it's free and is scalable. By this I mean you can start simple with a Cheap £5 Breakout board and throw some half decent Closed-loop steppers on it which will be in £300 region and away you go, you'll just about do it with £500. Then as you have the money and learn you can build up the system and improve it with ballscrews and more advanced Mesa cards.
With Mesa cards and Linux CNC you can do just about anything, including using hand wheels for semi manual control(still need PC on). Clive S is the man for Linux CNC and he's converted the same machine using Linux CNC and it used handwheels.

I wouldn't look at any other route unless you substancialy increase the budget.

[GeorgeS]

Thanks for all the advice, I'll deffinately be converting my mill.

Would I still be able to get half decent results using the stock leadscrews? Also (posibly a stupid question) should the steppers be directly attached to the leadscrews where the hand wheels are, or can they be connected using belts to pulleys mounted where the hand wheels are (seems a lot easier to do)?

[Doddy]

You'll have backlash with the existing screws - you can measure this with the amount of play on the hand wheel before the bed moves.

You can choose how to couple the motors - either way works.

I can attest to the fact that a hand wheel rotated as speed by a stepper, around groin height, is a thoroughly unpleasant experience.

[JAZZCNC]

Thanks for all the advice, I'll deffinately be converting my mill.

Would I still be able to get half decent results using the stock leadscrews? Also (posibly a stupid question) should the steppers be directly attached to the leadscrews where the hand wheels are, or can they be connected using belts to pulleys mounted where the hand wheels are (seems a lot easier to do)?

Like Doddy says you will have some backlash but how much depends on your machine but it can be lessened by using backlash compensation which is a software work around. It's not perfect but can help a little and will certainly get you going.

You'll probably find using belts will be required because won't be able to directly mount easily. But that said it's a good thing to do any way because it lowers the resonance on the motors and makes them run smoother. If was Me I'd be fitting belts regardless for this reason alone.