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Norfolk UK
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Anyone seen this http://www.coolcomponents.co.uk/catalog/imodela-milling-machine-p-1011.html I have been thinking of making/buying a small CNC and had considered this http://www.ebay.co.uk/itm/CNC-3020T-DESKTOP-ROUTER-ENGRAVER-ENGRAVING-DRILLING-MILLING-MACHINE-NEW-q9-/180832846184?pt=UK_BOI_Metalworking_Milling_Welding_Metalworking_Supplies_ET&hash=item2a1a7a4168 but the need of parallel port control put me off but the first link does USB. I would love to make it all myself but don't have the tools or room to build one. Anybody had experience of either or could suggest alternate cheap and small machine?
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Central Indiana, USA
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I would visit www.cnczone.com.  The forum has information on just about anything you want to buy/build.  I built a cnc router for about $500US.  The cutting area on mine is 24" x 36" and 6" height.  It's not a fast machine, but it does a nice job.  I built a Sosylva machine.  The most expensive parts will be the stepper motors, motor controllers, and power supply.  Good luck!
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Dubuque, Iowa, USA
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Parallel port control with CNC is still the standard (for whatever reason). You should look at USB control as being proprietary and limiting your software options.

If you google for "3020" CNC you'll find lots of commentary on them.
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Parallel port control allows direct access to 4 motors without relying on other circuitry to keep the timing right. Generally uses Step and direction motor controllers. You might look into GRBL which is an Arduino/ATMega328 based program. Uses the serial port from the main computer to send it the GCode and then handles the motion for 3 axis.

Mach3 is a very capable program and will work with up to 6 axis.

You can look at some work I did on making an ATtiny2313 based driver - http://arduino.cc/forum/index.php/topic,84809.0.html - I started using Arduino to test the idea and moved to AVRStudio4 for the final.
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I've built two now.

The first one I built from scratch based on this design:

http://www.instructables.com/id/Easy-to-Build-Desk-Top-3-Axis-CNC-Milling-Machine/

I'm happy with it now but it took way too long to build (about three months from beginning to end) and because I didn't really know what I was doing I overspent on some things and underspent on others, which I ended up replacing. All told with hardware and electronics it cost close to $700, but if I had to do it again I'm sure I could for for less than $500.

Two things I like about the design: 1) the design scales up and down easily (you just get different lengths of pipe for the frame), and 2) the gantry is fixed so it was simple to add a vacuum hose.

Two things I didn't like about the design: 1) Spinning threaded rods is inherently slower than pulling a belt so maximum speed isn't as fast as I would like (about 3/4 inch / second), and 2) since the gantry is fixed the base needs to be at least 2x your cutting area.


About two months ago I bought a ShapeOko:

https://www.inventables.com/technologies/cnc-mill-kits-shapeoko

I'm using mine as the frame of a pick and place machine, but most people use it as a CNC mill. I got the mechanical kit and ordered the electronics from SparkFun (motors, switches, and a Uno board), Pololu (motor drivers) and Amazon (power supply). Total cost was under $450.

Assembly was a breeze (two evenings for the mechanicals, one for the electronics, and a weekend to tune and test). I'm really happy with it, and if I was starting over again I'd get another one of these frames instead of building my own from scratch.

Some on the ShapeOko forum (http://www.shapeoko.com/forum/index.php) have mentioned you really need dual motors on the Y axis to reduce backlash; I can't comment on that because there's never lateral pressure on my pick and place nozzle head so there isn't any.

I agree with kf2qd that you should look at running GRBL on an Arduino to drive everything. It's got an active support group, the source code is well documented and easy to extend, and it's easy to install.

I hope this helps. Good luck!
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Norfolk UK
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Thanks for all the info and suggestions. Due to space limitations I cannot have a large(ish) machine but greed on my behalf I would like as larger cutting area for smallest footprint possible and accuracy as I hope to machine the odd surface mount component PCB.
The ShapeOko looks interesting but they are not taking orders ATM and I would probably be badly stung on shipping and import duty here in the UK. I am wavering towards the CNC 3020T as it seems to have a good ratio of footprint/cutting area though the iModela iM-01 also appeals because it easily flat-packs for storage but at the cost of cutting area.
I don't like making snap decisions and will have to ruminate on it some more.
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For what it's worth Inventables just (today) started another round of orders on the Shapeoko mill.

I'm not sure what the import charge would be to the UK but there are several of you on the forums; there might be more info there.

I do like your decision to think about it; if I'd done more reading I could have avoided several mistakes I made along the way.
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Norfolk UK
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In my searchings I have found another possible contender http://gocnc.de/product_info.php?cPath=33&products_id=134&osCsid=b956a9c62c98651853968ca876599eb1 anyone have experience with this machine or company? It appeals because it's quite compact but with a large cutting area and looks well supported for spares etc. Also because it's in the Euro zone I don't pay import duty  smiley
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Dubuque, Iowa, USA
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In my searchings I have found another possible contender http://gocnc.de/product_info.php?cPath=33&products_id=134&osCsid=b956a9c62c98651853968ca876599eb1 anyone have experience with this machine or company? It appeals because it's quite compact but with a large cutting area and looks well supported for spares etc. Also because it's in the Euro zone I don't pay import duty  smiley

Doesn't look good to me. Y axis looks wobbly, the controller looks pretty weak, it uses bronze nuts with no way to adjust backlash on what look to be very fine thread leadscrews. It doesn't have flexible couplings between the steppers and leadscrews. All of the pressure from the leadscrew thrust is put onto the stepper motor.

The Chinese 3020 is made from aluminum and has a better structure. It uses ballscrews and ball bushings on all axes. The spindle motor is much better than the rotary tool on the German machine. Granted, it's also Chinese, but it's also an overall properly designed CNC.
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