the out line function

[Marcel]

I have been playing wit an image to put on some coaster for some friends. 
The problem I am having is  that I make them to size in inkscape and save them as a png.
I bring them in to t2 and they are not to size.   I make them 101.6 mm or 4"  in inkscape  and then when they come into t2 they are only 36pixels which I am taking that equals 32 mm.
Ok so I scale it up and it is ok. 

So I put the image in the center of the 101.6 mm which is the size of the coasters I an making. which is close when I dither the image just blk & wht.
the thing I want to do is then trace around the image to get sharper line.  so when I trace it and then send to the laser it is not in the same location.. it is like it took the image outline and moved it to the bottom left of the image.
the question to all is how do i get this to work so the trace goes around image and lines up with the edges so it does not look like I am coloring out of the lines?
I am attaching one of the images the one I have been playing with.
also is there another file format to get images out of inscape  into t2 other then dfx & png?

[Zax]

If the attached image is the one you exported, then it is 360 x 360 px. If you engrave it at 0.1 resolution it is 36 x 36 mm.

Images don't have physical dimensions, unless you know the resolution they are going to be displayed at (or printed, engraved).

So to make it 101.6 mm, and engraved at 0.1 resolution it needs 1016 pixels. If you change the resolution to 0.2 then it is going to be twice the size and engrave at 203.2 mm.

You should use black/white mode for a logo like that, not dithered.

How are you doing the trace, are you using Sketch Plus or doing it manually? If you have relocate origin enabled it will shift the trace to lower left and not align.

JPG, BMP and PNG are image formats.
DXF, PLT and GBR are vector formats.
PDF using Agastar's utility will extract vector information only.

Edit: Attached image with raster and vector (trace) combined, using SketchPlus and verified correct alignment.

[Marcel]

I tried to do it with the manual trace, the icon and the auto trace.  not sure of the sketch plus.

do you have a video that shows what you did here. and the picture that is blue and how did you get that from sketchplus.  is this a separate program.  I am new to this program  on my 3rd or forth week.

Because the way I did it it shifted the outline.

Thanks

[Zax]

The reason it shifted is you have "Relocate Origin" enabled in the Settings / Advanced Settings menu, so it is moving the lower left to 0,0 after you trace it.

What you are trying to do is called Sketch Plus, see the attachment on the previous post. All you need to do is enable the option in the Mode menu and click Auto Trace (or manually trace if you only want some portions).

I have attached a zoom in of your image showing how it will engrave and then vector trace the outline to improve sharpness.

The "blue" is one of the color choices in my simulation view, it's a feature included in T2Laser where you can see what the laser will do and run the G-code on a virtual machine. On the laser screen click the "View" button at top right.

[nottingham82]

When you make your PNG set the DPI to 254. That will give you the right size if you engrave at .1

[Marcel]

Thanks  I have been busy lately  so sorry not to get back to you.

But yes I found sketch plus and that helped me greatly.

but I still get the laser stopping for no reason sometimes.  And I get the message  (Index outside of array)  so is that something in the machine in the eleks board.

but all in alll things are starting to come around   I have watched the videos and read the manual and thing are starting t come together.

also  in the grbl firmware should use al the settings from your setup and just change the setting to make my machine dimension properly. 

[Zax]

I haven't seen that error before, when do you see it? Is it a pop up error in T2Laser or from the message window?

I added a "check mode" in the latest version 1.3t. It's a quick way to see if the g-code has any errors, it requires Grbl 1.1c or above to work correctly.

If you use Grbl 1.1e it has my defaults already, so you can just load that and tweak any parameters for your machine.

[Marcel]

It pops up  this time iwas about 3/4 way through an engraving.

it pops up in a window like box.  So if you have not seen it then it must be windows. 

I am  I think using 1.3t and grbl 1.1e  I have all the settings like yours except the one i need to change for the steppers to move the proper dim.  so 1mm = 1mm

I was just wondering if it might be a false trigger of the limit switches.   I am using a .47uf capacitor to stop the false triggering. 

 I have read in another tread that you use an ttl laser  I have a 7watt head that has ttl but not sure how to wire it,  it has three wires   a 12+  GRND  and a ttl  yellow, any ideas has how to wire it to the eleks 7 board.  I would really like to use it.  I was using it on the plotter with a grbl shield and just triggering a relay to turn it on and off.  but changed to this 2.5watt with the eleks board was put on.  Anybody that can help with this wiring I would appreciate it. as I would like to do some of the dfx files I so faster seeing the 30" X 20"  printing airplanes on foam board.

[Zax]

Please zip the gcode file and email it to me so I can check that error.

This thread may be of interest, it shows how we are hooking up the TTL lasers.

http://benboxlaser.us/index.php/topic,1391.msg16792.html#msg16792

You only need 3 wires, power (+) ground (-/GND) and signal (PWM).

[Marcel]

i DID NOT SAVE THE G- CODE SORRY I AM JUST LEARNING.

[Marcel]

Which thread is that the one we are in right now !

[Zax]

No, the thread I forgot to post the link to. Fixed!

If you get that error again, perhaps you could either screen grab it or send me the procedure to recreate it.

[Marcel]

Zax, I do not know I tried to search fixed  but had know luck. is there a link to where you said they should hoe to hook up the 3 wires

[Zax]

The link above includes a post where I consolidated all the discussions, including this thread:
http://benboxlaser.us/index.php/topic,402.msg6591.html#msg6591

I think it will answer your question.

[Marcel]

Thanks ZAX the helped a lot not I will try the 7 watt head. and see how it works.