engraving issue

[The-Artful-Badger]

Hi guys, I use inkscape to draw bespoke artworks. In certain areas of the draw drawing I use Axidraw to fill in an area to be engraved. I have no issues with the file in sheetcam when I set it up for my cnc table. The issue I have is that if I have an area that i have selected to be cross hatched, it wont do all of the engraving in one direction and then do all of the engraving in the opposite direction to give the cross hatch effect. Lets say it was a large letter S to be engraved. it would only draw a certain amount of lines before it stops (nature of the curve of the S) it would then move to another part of the file and engrave that. it would then come back to the letter S and engrave some of it in the opposite direction. Eventually it will have cross hatched the entire letter S but the way the light reflects off of the Aluminium that has been engraved at various times, the appearance is patchy due to the variable engraving process.

is there a way to get sheetcam to complete the engraving in one direction before switching to the opposite direction to complete the cross hatch ?

[djreiswig]

You need to set your cut sequence. If you click the start points tool and then right click on the work area there is a menu option Quick Cut Sequence. It will allow you to order the start points however you want. Press Esc to dismiss the box when you're finished.

[The-Artful-Badger]

Hiya bud, the problem is that it doesn't complete the engraving for that section/area. The engraving tool just goes back and forth in a straight line as it should but then it stops, it then starts to engrave somewhere completely different on the artwork and then comes back to the problem area in question and starts the cross hatch in the opposite direction for the first area that it never fully completed. I set the spacing and the angle of the hatch in Inkspace, I can choose single hatch or cross hatch.

for the hatch fill to look correct it must first engrave ALL of the lines (lets says Left to Right at 30 degrees) then it needs to engrave all of the lines (right to left at 30 degrees) if it does a part job the reflection of the light from the finished engraved area gives the appearance its been engraved wrong purely down to the reflection of the light bouncing off the engraving and yes it is very noticeable


its as though theres a setting in sheetcam that spaces out the work "when plasma cutting to avoid warpage" even though im engraving

hope that makes sense

[djreiswig]

Yes. Check the order of your start points. Each direction is probably a different path, so when it completes one direction, it goes to the next start point. You need to order the opposite angle as the next start point in the cut sequence.

[bLouChip]

@'artful - I'm new to scribing but as I experimented with different hatch styles for interior of text characters, I noticed the same issue. I use Lightburn as my 2D CAD, and I can control the hatch construction such that I have 2 layers for cross hatching, one layer for each raster angle. Then in SC, two operations have to be used, one for each of the raster/hatch layers, so all hatch lines of a given angle are scribed together and of course for all shapes in that layer. Then because Operations execute in the order they are listed, the next layer of hatch line angles are scribed. SC seems to do a great job placing start positions as the same end of all lines in a layer, so that's nice, I assume because it using a Marking Tool. The order of scribing in an Operation can be somewhat controlled using the 'cut direction' slider in the 'Cut Path' tab of the Operation window.

You mentioned Inkscape can build single hatch and cross hatch, so perhaps what I'm doing in Lightburn is single hatch.