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View Full Version : NEW MEMBER: Hello from Sussex



Pointy
10-12-2013, 07:52 AM
Hi,

I am Les from Sussex, I am fairly new to the world of CNC, I really only got my cheapo 3020 for making PCB's. To be fair it has performed really well, and I am pleased with my purchase. I have already done a bunch of mods to the machine but I am thinking of upgrading the entire electronics and building a new enclosure for it. I thought it would be wise to get some advise and this seemed like the premier place to get it.

Regards,

Les

EddyCurrent
15-12-2013, 09:17 AM
Welcome Les, are you upgrading because you have problems or is it just an interesting project for you ?

Pointy
15-12-2013, 06:10 PM
Welcome Les, are you upgrading because you have problems or is it just an interesting project for you ?

Thanks Ed,

You did reply to my thread (http://www.mycncuk.com/forums/mills-routers-lathes-commercial-machines/6896-yet-another-chinese-3020-cnc-upgrade-thread.html#post52181) already.

The upgrades are just a fun project, but there is one annoying problem which has now happened 3 or 4 times...

The Z axis coupling becomes loose and the axis drops down from the motor. Last night is was the motor side that came loose, previously it had been the leadscrew side. Fortunately it wasn't during a job and happened while setting up, but it was a major pain to take apart and tighten up. I have re-tightened everything again and put some thread lock on the screws this time. The coupling looks something like this. (http://www.ebay.co.uk/itm/8x8mm-CNC-Motor-Jaw-Shaft-Coupler-8mm-To-8mm-Flexible-Coupling-OD-20x26mm-02-/300697660000?pt=UK_Sound_Vision_Other&hash=item4602fa2a60&clk_rvr_id=560612065845&afsrc=1) Is there a better alternative?

Regards,

Les

EddyCurrent
15-12-2013, 06:22 PM
Sorry Les, must be loosing my marbles :stupid:
I can't understand why the axis should drop because the coupling should not be holding anything up, it should just be connecting the motor and ball screw shafts.
The ball screw should have a bearing and support block at each end.

Pointy
16-12-2013, 09:50 PM
Sorry Les, must be loosing my marbles :stupid:
I can't understand why the axis should drop because the coupling should not be holding anything up, it should just be connecting the motor and ball screw shafts.
The ball screw should have a bearing and support block at each end.

Well if the coupling becomes loose the motor/leadscrew separate so the axis falls down. There is nothing else holding it and don't understand how there could be as it has to move up an down. I don't have any close up pictures but this is same machine.

11020

Regards,

Les

EddyCurrent
16-12-2013, 10:13 PM
Sorry Les it's me. I'm not familiar with these machines, I was thinking of a Z axis similar to this Z Axis 250mm Ballscrew Plain Mount (http://www.cnc4you.co.uk/index.php?route=product/product&path=87_90&product_id=200)
As you say it looks like the leadscrew screws directly into the Z axis block so if the coupling fails the whole lot drops.
Maybe someone else with a similar machine has a better arrangement ?