New guy finishing off a mini mill build

[Patcho1961]

i will endeavour to remove the offending screen, my first ry will be with a screw driver if that does not work i will resort to a hammer.
i do have an BoB supplied with the box of bits i got with the machine but no data sheet on it, maybe i will try swapping them over, totally understand its not worth the time if the offending article is only a few quid.
more just trying to work out if its dodgy chinese board or me being dumb!

[Patcho1961]

screen removed (screw driver worked) pics in album of naked BoB, back of BoB and removed screen

[Colin Barron]

Hi everyone, I am a toolmaker and have some experience in using cnc machines, but have decided to build a small cnc mill for fun really.
I'm not getting any younger and I like the idea that a machine can do some of the work while I just push a mouse around... lol.

My question to you guys is should I set the machine up using mach3 or would it be better to use mach4, as I am just starting which would you go for.
I will probably be producing fairly simple components for use in model steam engines and the like and I think mach3 can and would do everything I need, but I don't want to have to learn something new a year down the road if I meet limitations with mach3.

So there you go people, answers on a postcard please and stay safe,

Steve

You have experience of using cnc machines, would it not be easier to learn DIY controller cnc which i assume is similar. If you purchase a cheap Chinese controller (£200) or a slightly more expensive one (£600). The £200 will have very little backup but there are forums and you tube support. If you choose the £600 you should get more manufacturers support.

[Doddy]

Steve,

The blue-board - that has non-isolated inputs and I would not lose sleep over it being susceptible to electrical noise, resulting in spurious limit/estop triggers.

The green card actually looks quite good. I'm struggling on a Mac to look at it properly (the "trending" articles obscure the images on both Safari and Chrome), but it looks to provide isolated inputs... and ironically isolated outputs (I say that because just about all stepper drivers then have isolated inputs... you can have too-much isolation!). At this point, personally, I'd be trialing the green card. As earlier, you might need a second PSU - check the board silkscreen for. 12-24V... it's need no more than 500mA)

[Patcho1961]

Thanks doddy,
I am planning to swap out the BoB tomorrow, I think I have found the right data sheet for it, it appears to have the ability to have 2 supply inputs (both 5v) or if the jumpers are set right you only need one, we shall see.
I will let you know the results after testing.
For info the board is a DB25-1250

Steve

[Doddy]

I've come across this from another site...



Yeah, you can short VDD to +5V - that will allow you to run on a single PSU. You don't get analogue spindle control (but neither does your other board, and I don't think you're yet set up for it). The '817 opto devices are slow, so you might not get the optimal throughput through the Opto-coupled outputs (as I say... you can get "too" isolated :) ) so keep your drivers at x8 to keep your feed rates up. The slow behaviour on the inputs is largely irrelevant.

If you wanted to go to proximity sensors on limits then you might need to decouple and raise VDD to about 8-12V. The higher you go, the more you may need to add additional resistors on the stepper-driver interface, and on the input terminals. Best to try for now at 5V and bridge 5V/VDD, using microswitches for limits.

[Patcho1961]

OK people, swapped out my BoB and yay, limit switches and E-stop all working fine.
Will spend next week tweaking and I think I might have to do some work on the ball screw to the z as there appears to a lot of backlash.
Thanks to all for your help, I am sure I will have more dilemmas along the way so keep an eye out for my next crisis

Steve

[Patcho1961]

Jazz wish you had said earlier, I ordered UC300ETH + UCSB BoB with cables and UCCNC license from CNCDRIVE on saturday and sent money transfer this morning, would have been easier buying from you I reckon, price was pretty good £173 including delivery but not sure if I will get hit with any import tax given that its coming from Hungary.

on another note where do you buy your ball screws and ball nuts from? I have horrible backlash on the Z of my machine as the screw and nut have been badly fitted so I want to replace at least the Z ball screw and nut, still checking the fitment of the X and Y but they do seem like they have better fitted.

steve

[JAZZCNC]

Jazz wish you had said earlier, I ordered UC300ETH + UCSB BoB with cables and UCCNC license from CNCDRIVE on saturday and sent money transfer this morning, would have been easier buying from you I reckon, price was pretty good £173 including delivery but not sure if I will get hit with any import tax given that its coming from Hungary.

on another note where do you buy your ball screws and ball nuts from? I have horrible backlash on the Z of my machine as the screw and nut have been badly fitted so I want to replace at least the Z ball screw and nut, still checking the fitment of the X and Y but they do seem like they have better fitted.

steve

Sod's law hey...Lol.

Yes, because you have only paid £173 that means you haven't paid EU Vat so you will get hit with UK VAT and Import duty and possibly a ripoff charge by the shipping agent now we are no longer in the EU club.

Ballscrews I buy from Fred at BST in China but they are closed for 3 weeks now due to the Chinese new year holiday.

[Patcho1961]

indeed it is sods law!

I can't be waiting 3 weeks any where in the uk to get something decent?
i have been looking at motion control products in Bournemouth (https://www.automationshop.co.uk/cat...crews/id/8950/), they sell ball screws and the like made by Gten, they look alright but you never can tell

anyone have experience of buying from them?