Hello from Barry

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19-10-2014
philcobt

Hello from Barry

Hi All,
Just a brief introduction.

I am a newbie/novice to the CNC world, not 'green' as I have built a machine resembling something like the one from the MyDIYCNC site as an introduction to the hobby. It worked of sorts except when I attempted to cut a PCB. Unfortunately the axis drive & mechanics were too slack, had backlash, drivers too poor, missing steps, all of which which resulted in the 1mm wide tracks being reduced to zero. Not a good outcome for a PCB!!

Financial considerations have meant building on a budget.
The setup is:
4 axis stepper driver (TBA6550)
Recycled steppers
24v PSU
LinuxCNC

I have also played with the trial version of CamBam too.

When I started trying to fix the problems, a friend offered an engraving machine (table = 26" x 13") without the engraving head/ Z axis components at a very reasonable price which I couldn't and didn't refuse.

So the current project is to build a new Z axis system with an 800W water cooled spindle + VFD

I have come up with a design and I have started cutting parts. 1 down, loads to go.

As a newbie I mainly lurk on sites like this as I do not have the experience or skills to add any comment which will be of any real value to anyone else.

Regards,
Barry.
19-10-2014
JAZZCNC

Re: Hello from Barry

Quote:

Originally Posted by philcobt

As a newbie I mainly lurk on sites like this as I do not have the experience or skills to add any comment which will be of any real value to anyone else.

Hi Barry welcome,

Yes you do have experience and obviously some skills as you have designed and cutting parts now. This does have some value to those who are lurking with Zero experience and what they now believe are no skills. But like you this will change if or when they take the plunge and they will develope skills along with experience and enjoy every minute of it I hope. So YES mate your input is very important and of great value as it shows you don't need to be Guy Martin and have workshop full of tools to have a go.

This comment below shows it worked and you succeeded in your goal which is the main thing.!!
The fact it was bit sloppy is the learning curve but of "most importance" is the fact you were brave enough to admit this, which has great value as well. Lots of first attempt machines get scrapped and nobody ever see's this only the 2nd or 3rd attemps ever get seen.
So you showing that it's do-able but still needs some attention to detail regards components used is off great value because it will show those lurking that cutting corners is a recipe for poor performance and hopefully save someone wasting money and lead them to a better machine.

This is truely Valuable and experience at work.!! . . . . . So well done you and hope the new machine works well.

Quote:

Originally Posted by philcobt

I am a newbie/novice to the CNC world, not 'green' as I have built a machine resembling something like the one from the MyDIYCNC site as an introduction to the hobby. It worked of sorts except when I attempted to cut a PCB. Unfortunately the axis drive & mechanics were too slack, had backlash, drivers too poor, missing steps, all of which which resulted in the 1mm wide tracks being reduced to zero. Not a good outcome for a PCB!!
20-10-2014
philcobt

Re: Hello from Barry

Hi JazzCNC

Thanks for the welcome and your comments. Fair point to most.

I certainly agree that it's a learning curve and a steep one at times but it did convince me that the effort is worth while. I'm still going & haven't given up yet.

I suppose the biggest problem I had was that using recycled stepper motors of unspecified characteristics. That threw a huge spanner into the works. Trying to get the settings in some sort of working fashion by trial & error caused many headaches with the driver box from China. Lots of unknowns all contributing to the confusion.

Understanding that NEMA17 motors all have different electrical characteristics and that the NEMA17 is the mechanical specification was a real light bulb moment :friendly_wink:

I did follow most of the plans for the MyDIYCNC machine but again realising the limits of any design is most important and not expecting too much (which I did). I believe there are ways I could improve on the drive system in particular which would make mine into a usable machine but that one is resting for now at least. I was working on an early design and they have implemented many 'new and improved features' overcoming some of the problems I had.

Onward & upward.

Regards,
Barry