PCB millig problem

what program sets up the gcode? I used pcbgcode.ulp in eagle cad and it works fine. i used a depth of -.15mm, x and y feed of 250mm/min at 20000rpm, and tool diameter of .3mm. i broke a lot of bits till i found the correct one at amazon
https://www.amazon.com/gp/product/B00QU80Y0M/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
i set the z zero in the center to average any tilt.

Well .. lots of people have the Steppi running with exactly the same drivers. And for PCB milling ... there are no big forces involved.

I think there are 3. possibilities:
1. You loose steps in one direction more than in the other
2. You still have backslash
3. You entered backslash compensation values in your software and forgot to remove them after adjusting the hardware.

With high quality engraving tool your isolations will be much narrower. Have a look at the images in this thread
And using othe PCBs based on hard paper will increase lifetime of the tool. Nothing worse than fiber glass epoxy.

Hi QdeWolf.

I got the dxf of the milling profile from this forums. It's a circuit related to estelcam direct control.
More I have used Estlcam10 (veryvery nice software by the way.. thanks to Kristian).. to better understand how good the cuts will look like when using 0.4mm milling tools.

just don't understand what could be vrong with stepcraft nd why for this mini cnc it's so hard to make mechanicl adjustment or how to remove backslash.

I saw MagIO2 respnce but I really don't know how to make backslash compensation and did not used them before. I will check thosu once again if this is the case and how to do this.. and if they are needed. I saw stepcrafts recomed making some backslash compenstions for very good resolution as I remember.
thanks... but really can't unerstand why your machine can do even smd pcb milling and mine cannot do nice normla 2.5mm spacing miilings properly.

Hi,

A question - what motion control have you on your machine, UCCNC/UC100 or something else?

Looking at your picture of an engraved board, there are significant depth variations, so the laminate is probably not flat. IMHO if you are engraving narrow tracks and isolation you probably need a vacuum table to hold the laminate. Mine is home made from wood and mdf, and was machined flat in situ with a new 1/4" endmill.

As far as tools are concerned, I use a 30degree single flute carbide bit whose end diameter is approximately 0.1mm (.004"). Spindle speed is 18000rpm and engraving speed is set to 500mm/min. Cutting depth for a single pass I normally set to 0.010"

Backlash compensation is essential to making fine tracks, but without knowing what motion control system you have I can't offer any advice. Suffice it to say that you should be able to reliably engrave 0.010" tracks with 0.010" isolation.

I've posted several pictures of my efforts on this forum, so these may give you some idea of what is possible - and I am still learning!! I generate schematics and board layouts using Eagle, with pcb-gcode generating toolpaths. These will run unedited under UCCNC/UC100.

Peter

He told us ... he is using EstlCAM. It has a build in machine control, which requires an Arduino to generate the stepper signals. And even better, it allows to scan the surface before milling and would do a correction of z-axis by itself.

What about the spindle? Is there some play in the spindle? I would suggest to setup everything and then push and pull in all directions at the tip of the endmill. If you have a backslash problem it must move somewhere.
If not, you must be loosing steps, having mechanical reasons or I would guess less likely electrical reasons.

No. I use Estlcam to generate the G-code.
I use for milling the WINPC-NC Proffesional USB version that comes with the Stepcraft milling machine as an option.

I am trying to get rid of the WinPC-nc version if I succesfully manage to engrave this board , and make the arduino Shield required to control the Stepcraft trough the Arduino via Estlcam software.

I seem to be ages from this point.

The nicest looking results on that PCB board I made are also made with 1 single flute 30 degree angle, so thanks for this tip, as I did not choose a bad tool.

I just need to understand the Axis that is loosing steps and why? Maybe still this machine has some mechanical issue...
I will make some marking on the x&Y axis and mill some more stuff and see witch axis is loosing steps.
After this I plan to make test backslash function and how this should be used to increase the accuracy.

From my copper traces apparently my problem is in the X beam .. as sometimes the traces are wider and somethimes too thin for keeping copper. (Strange that for Stepcraft X beam is what for other routers and CNC's I ave made is Y 🙂 )

I will come back with what should be made, and my results in the following days. Until now.. I's just advice no one to buy a stepcraft for PCB drilling unless they need to fix it all day long :(.. as at least they don't reply by mail and the product ways of adjustment is just and trial and error compared to simple linear bearings that just work.

Thanks.

I am sorry to say this, but, having a look on the image, my guess is that you have problems on both, x and y. You have to look at the horizontal and the vertical traces. For both you find examples showing too narrow and too wide traces.

Would calling Stepcraft be an option? By mail you simply end up in a stack of mails and it can take a while.

WinPC NC has a setup for backslash, as far as I remember. I only have starter version and I don't use it anymore, so I can't tell you out of my head where it can be found. Someone else? Maybe worth to double check these settings, maybe changed by accident, maybe strange default settings ...

Do not want to write to much at this time, found some mistakes in the used file and asked some questions to figure out, what´s the reason...

...btw. of course answered the email, but needed a day...

Hi ThomasDbg.
There was no mistakes in my g-code file.
Probably you don't know how to interpret them well enaugh.

The traces were milled and programmed for a 0.3mm mill, and the name of the tool remained 3mm.
The name of the tool does no count. I could have been 1km diamter mill, and then probably your reply would have been I fount Out that ClaudiuG whants to drill 0.4mm paths using 1kilometer diamter drill :)).

I'm nt such a noob you know.
The deal is that I hve build until now about 3 or for big cnc-s and this is the only one I have bought (Steppy 420).
Some how i regret it as the product has lots of flaws.
The nice side is that is looks good, and the bad sides is that is.. very hard to adjust, and to be able to quickly make work.

I found out I dismantled this stepcraft almost 2 times this week. Now the x and Y gantries and the Z don't have any type of play when pushed by had slightly, or more..like before.

I found out the PCB's now look better after mechanical modifications and having a 0.3mm/secod advance speeds and will provide some pictures just when I finish the new PCB that is currently being in work.

I would advice any procedure or documentation describing calibration procedure or how we should adjut backslash as I could find this nowhere.

Here is may latest results... a little better PCB, but still with issues and not functional..

I's like to mention that I spend time to adjust stepcraft milling CNC, enaugh to build a new prusa I3 3d printer.. and still not very good results..

Could someone in Spectraft please reply in this forum with cleare things to do? I marked with X and Y in the picture the axis of miling.

I also attach my latest g-code and I corected the name of the tools used in estlcam so that the Responce from Strpcraft would not be again offtopic.

What elese should I do ? Is thee any gcode for calibration of this cnc machine and based on this can I solve any of the axis issues ?

Claudiu, that isn´t right.

I´ve emailed you a Picture of your gcode and mine and showed you the error. Additional I´ve asked you to allign the machine carfeully and check the backlash.

I haven´t got any answer from you until today! Blaming in this customers Forum doesn´t help.

So let´s try to figure out, what´s the reason for your problem!

Enclosed you´ll find the two pictures, which show the mistake (according to your milled PCB).

...and of Course, as Long as you only name a router "Elisabeth" it will not do a radius correction "Elizabeth", You perhaps wonder, but at Stepcraft the people know this also...

So again, let´s stop blaiming and start solving your problem!

Btw. your new results are still bad!

Well please explain ho to align the machine..as you explain other things always but not where the problem comes from.
I agree my Gcode is first run and could have an issue in the TOP area.. but as well what steppy is milling is not consistent and does not look the same like a G-code file.. and this is the problem of this Spectraft product !!!

Or better please provide some gcode for calibration purposes that would allow us to find the problem and the axes that still has issues.

At this point I don't understand exactly which axis has a problem, mainly because sometimes the problem does not appear in that axis.

I would not correct anymore the mechanical frictions because I barely made the steppy run, without stalling while making a reference positioning (with the front 2 screws still not completely tighten only).

This said we should be at least pointed with a better forum or procedure that explain how to adjust and calibrate our stepcraft machines or the resolution and repetitiveness described in the site is just a big lie, and it's quite far away from the normal user experience.

If your machine is barely able to move even with screws loose, your chances of making a decent pcb are vanishingly small.

You need to get your machine properly set up first - try looking through the posts on this forum to see advice given to users whose machines suffered similar problems.

When properly adjusted and with backlash compensation, tracks and isolation 0.008" (200micros) wide can be accurately and reliably engraved.

If you expect support from SC, you should stick to the support channels they offer, which are email, phone and maybe skype. The forum is meant to be a user forum with little chance to get heared by SC staff.

I don't see a problem in creating a simple "calibration file" on your own. Create a circle and mill it at different locations along the y and x axes.
If it is not perfectly circular but the start and end position match, you probably have a backslash-problem.
If start and end position do not match, you probably loose steps in one direction per axis.

Use the forum search to find solutions that worked for other users.