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Hi Jestha,
Thanks for the quick reply.

So initially, I was having dimension issues, even though I set up mach for mm it was still running in inches. I appear through persistence and **** right stubbornness to have got it working, I set the steps automatically through the settings screen and seem to have ironed out that little issue.

I know the timing belt is not ideal and would love to upgrade to rack and pinion, although I have been told that belt drive should work ok for now, I intend to put the nema 23s on to this at some point in the near future, yet another boat load of wiring issues to get over, bipolar, unipolar..... Duh, I am a little lost.

I have a feeling I have the homing and direction switches set wrong, although it travels the right direction when I load g code it appears to cut from the top left ( in plan) which in my head should be bottom left in plan!!
I know x is my shorter axis and should travel in a + direction, so probably crack that issue this weekend

 

Hi Jestah

No can do, I don't have Internet in the garage.
I will reconfigure my homing and limit switches to another axis on the table.

Can you recommend anyone for a set of ox plates??
I intend to put a second x parrallel to the original and double up on the Z plates and put 4 or 6 wheels on that too as well as doubling up the the timing belt so I have one top and bottom of my y, what do you think, this should eliminate any wear on one and saves using the servo belt?

 

Wow, what a pain in the arse my machine is being.
Almost every time I tuen it back on I seem to have another minor issue.
So bought a new limit switch for the other side of my Y and wired it into the 2 existing Y limit switches either end of the table so I can try to find perfect zero for both sides so it cuts square.
Now my limit switches are not working, oh the joys.

I will persist tomorrow when I have a few hours.
It has been a long but very cool build, electronics and stepper motors are definately not my strong point.

At the risk of sounding like I am ranting, if I tell you what I have my settings at could you tell me if you think it sounds right?

X and Y dip switches are set to 1 1/6 which is 16x200 (3200).
Timing belt is gt3 2mm pitch, the diameter of the cog appears to be 15mm.
Using this I got 106.66 steps per revolution.
Although when I use the auto set on the settings page it recalculates to 89.4 steps.
This does allow for pretty precise moves in mm.

The Z axis calculations I am not so sure about, I did have it set to 1 1/6 but really struggled to get it to move without making huge noise and having to turn up the velocity to get it to move, I changed this to full step on the dip switches and have now managed to get it sounding quieter but not as quiet as I would like.

I don't understand the whole concept of steps per and how that relates to the movement, in my head if the dip switches are set right then auto tune should be as close to precise as I can find, 1 1/6 I was told by my supplier of the electronics (system 45)) was going to give me the required level of precision.

What denotes acceleration and velocity, a mach3 tutorial I watched said listen for the sound, but this makes the numerical values ridiculous.

Anyway, thanks for you help.
It's nost appreciated.

Steve

 

Hi Jestah,

Hope life is good with you, I have taken the plunge and am now in the throws of ordering Ox plates and extra vslot for my X axis, managed to iron out the movement issues with mach 3, would you believe, operator error was the cause of the problems!!! Lol...

I am trying to find the respective code for auto tool zero which I don't fully understand but feel I need, as at the moment, I am using a lot of guess work for my Z axis and know I need the precision on that more than anything else.
Any ideas where I can get the right script from for this?

I have managed to make a probe using a crocodile clip and some PCB. It seems to work ok.

thank you for your advice and guidance.

Steve

 

Hi Gray,

If you search auto tool zero probe you will find more information than I can give you, however,

I started with Two pieces of wire, on one end I soldered a small piece of PCB (maplins) and attached the other end to my System45 (electronics).
The second wire I soldered a crocodile clip (maplins) to one end and return the other to my electronics.
The wires are connected exactly the same as your limit switches.
The principal being that you attach the crocodile clip to the shaft of your kress/router and when you lower the router the bit touches the printed circuit board and connects the signal.
You can test this by selecting ports and pins, inputs/auto select probe.
Attach the crocodile clip to the router, Just touch the PCB off the edge of the router and this will give you the required ports and pins
Although.....

You need to add script to the Auto tool button to get this function to work correctly, again Google is key or ask a more seasoned veteran on open builds who may explain it better than me.

 

Ah, no.
Sorry dude.

 

Hi ngoodfellow.

Firstly, thank you.

Secondly, here I go....

Because I used the parts I bought for the basic routy kit, this has led me to a few problems I am now in the process of rectifying......
1 new set of Ox plates waiting to be purchased to allow me the clearance required for the length of X axis.
1 new length of 80x20 for the X axis, ordered and waiting delivery.

The belt works ok though, I have managed to do a few pockets so far and the machine runs to the right dims, although and this is purely other people's opinion.......

Over time I am going to get some belt stretch, how much, I can't say right now as I have not gone into full on production mode but, I would recommend using linear rails in hindsight, if I had had the cash at the start and knew more about this I would have put on, it was only inexperience (and cost) that I used the timing belt.

Right at this moment the router struggles (deflection on the X axis) which can maybe be countered by cutting at shallower passes to keep torque down to a minimum, (obviously taking longer per cut).
As I said above, after researching other builds, I see that it would be prudent to add an extra section of vslot to the X to avoid this and have ordered that, also the routy kit has a section of 6020 which is upright, bolted to the Y axis gantry plate supporting the ends of the X axis, this is not rigid enough either, maybe works on a smaller machine, but certainly not the monster I have created.
I am now in the process of ordering Ox plates for the Y axis.....
1 to give more strength to the X and because the stepper motors connect directly to the Ox plates giving me extra clearance on the length of the X axis.
2 allowing me to ditch the s&it bit of 6020 that currently supports the X.
3 better cable management with the Ox plates.

All currently on order and waiting for delivery, will most definately post on the page as my build proceeds.

This place is a minefield of information and with the right amount of Google and general web diggin I have managed to get everything running the right direction,(speeds and velocity need fine tuning, but not going to play with this now until I have remedied the X and Y issues.

It has been very cool, very frustrating at times, but I feel like Frankenstein bringing his monster to life ( cue maniacal laughter) .

There are 4x4 machines on the market, but if you have a little bit of skill and can cut,use a tape and have a bit of a head about you, this can be achieved with parts available on the open builds store or generic suppliers, (vslot, tee nuts, solid wheels, etc) you can build one a lot cheaper than list price on many sites.

I hope this helps.


Steve

 

Hi Jestah.

Haha,

Yes.

I made my own auto zero plate out of some aluminium copied and pasted some script for the button and it works a treat.

Happy day, now just waiting on Ox plates and another bit of gantry for the X axis, too much torque/deflection at the minute.

I have managed to cut some pockets fairly successfully but anything more than a mm or two and the X starts to bend on the Y axis uprights which were off the routy.

Hence the reason for the other parts.

But slowly does it, it's been six months now, a few more won't hurt me.

Regards

Steve

 

Hi,

I would say that if you create your own cnc machine you not only have the knowledge and skills to understand it but it also is to your design and size.

A company called Robocutters have an 8x 4 machine on their site, it looks cool I think with the optional extras it was over £3k inc all electrics etc.

On average the prices I could find for a new 8x4 machine was about £4k, obviously yours is not going to be as big so just cost half in theory

I think mine has cost me about £1500 -£2000 and I understand fully how it works where I can improve it and what I can do to make my life easier.

Does the ox cut the 4x4 to the edges?

It will be interesting to see your path.


Now to learn and understand Mach3 and VCarve pro. Grrrrrrrrr

 

That's a shame. I had minor issues with them but they always came through. Missing items were dispatched. I had to drill a couple of pieces for my machine but then I bought individual items from them and not the whole machine.
Please bear in mind that Robocutters buy form external sources and any manufacturing defects would generally have been machined from a third party. Just a thought before you slate them online!!

 

Not my place to question you but have you spoke to Colin?