Impact Engraving.

[Pinky]

Sadly no, moved away from that company awhile back to start my own.

[Tweakie.CNC]

As a follow on from the first post in this thread....
Nothing is ever simple and something that becomes apparent when we start experimenting with impact printing from GCode files is the phenomena of ‘banding’.  When an image is mathematically processed to create a halftone it must not subsequently be scaled or have the aspect ratio altered in any way otherwise banding may occur. It does not always happen but when it does the result is a spoiled product – the following image was accidentally scaled and the pictures show the result. The, otherwise nicely distributed, dot pattern has formed into groups and suddenly they become noticeable.

Although I keep trying not to make comparisons, because of the entirely different method of operation, the Mach Impact / Laser plugin calculates the halftone dot pattern on the fly so does not suffer from this problem and even pre-prepared halftone images which have been scaled get corrected by the plugin at run-time so everything turns our right in the end.

Tweakie.

[Tweakie.CNC]

This was just a test run but I am really quite excited by the results.
The DotG generated code consists of 467,517 lines and with 4 lines of code to produce each dot, the image consists of 116,879 dots which took just 1.5 hours to complete. With a stroke length of 1mm the little electromagnet has now shown that it is capable of producing at least 21.644 dots per second (axis movement time has been ignored in the calculations), which is about double my previously achieved speed.
Instead of sounding like an ASR33 Teletype my CNC now sounds like a Gatling Gun and although not quite as quick as the Roland Metaza it is getting closer.

Tweakie.

[Dan13]

Brilliant Tweakie! And you always know how to best photograph and exhibit your work.

Are you saying it's around 21Hz? Then I think I was close with my experiments. Any chance you could record the sound? I would be interested to compare to mine, since I have no idea how better to estimate the frequency. How did you?

Dan

[Tweakie.CNC]

Hi Dan,

For the purposes of the frequency calculation, I ignored the axis movement time and divided the number of dots by the total time taken.
I have already been asked to make a short video – I will post the link when it is done then the sound can be heard.

Tweakie.

btw. Nice job you are doing on that milling machine – very professional.

[Dan13]

Hi Tweakie,

Ah... so actual frequency is even higher. Will be interesting to hear the sound.

btw. Nice job you are doing on that milling machine – very professional.

Well... I guess the only reason it would look like a mill is it being a Chinese lathe Thanks anyway

Dan

[Tweakie.CNC]

Sorry Dan - nice job you are doing with the lathe. 

Here is a short video clip with the sound of the electromagnet. http://hobbymaro.puhasoft.hu/Tweakie/Impact1.wmv

Tweakie.

[Dan13]

Thanks for the video, Tweakie. Now I have a clue what 20Hz sounds like. It works fairly fast considering it stops at each dot location.

Nice smiley, by the way.

Dan

[flamuria]

Hello All, can somebody tell me how do i connect a electromagnet with mach3 for photo engraving

[Tweakie.CNC]

Hi Flamuria,

There are a number of different ways in which it can be done.
The method pioneered by Robotmar is perhaps a good place to start  http://www.machsupport.com/forum/index.php/topic,16446.0.html

Tweakie.