Additional settings Cut acceleration

So I bought a new laser with more than twice the power… I wanted the extra speed that comes with more power as well as the larger table… So far, so good… Im able to plow through acrylic at twice the speeds i was before, but I have a problem… The actual start for each cutout is not cutting through with enough time as it begins and as a result, one side of my cutout starts with a slant, as if the laser hasnt quite had enough time to do its thing right at the beginning of the cut, but buy the time its moving, the issue is no longer there and the material is finished exactly how I want it, but the beginning of each cut looks the same, as if the laser started to quickly or without the much needed delay to get a consistent cut from the beginning of the cut. Any advice on settings that will help me here, im at a loss… Only thing I can find is additional settings and the cut acceleration, but its default setting is 3000mm/sec and I have no clue if changing that will even help with the initial cut. Thanks for any help to resolve this issue, otherwise Id say things are perfect, but all of my parts show the beginning of where the laser started cutting and didnt quite have enough time to go through and leave a clean straight line, but then as the laser moves, it works itself out.

There’s a reference on github to cut-through mode:

Enable “Cut-Through” Mode

This setting is only available for Ruida and GRBL based machines. Enabling this setting will allow the laser to dwell in the same position after initially firing or before turning off based on the settings below, and is useful for piercing thick materials before the cut starts.

Start pause time (ms): Number of milliseconds to fire the laser before moving
End pause time (ms): Number of milliseconds to fire the laser at the end of a move
Power (%): Percentage of laser power while paused

This parameter is found by double clicking on the cut settings for a specific layer.

The ‘Additional Settings’ are only for the simulation engine used in the preview, to tune it to match your laser settings for the best time estimates. They don’t affect your controller at all.

Fred’s suggestion of using the Cut-Through option is a good one. You can also try increasing the Min Power setting if you haven’t done so already, and you can use ‘Overcut’ - this keeps going past the end of the cut, as though it’s going to do another pass, but only for the distance you specify, which helps with beam drag (that’s what your issue likely is).

You can also try using Lead-In and/or Lead-Out, but they’re a little more complicated to use.

Thanks Oz, I think cut through mode is more what Im looking for, the part drops at the very end so cutting past final cut point could be disasterous, what im looking for is a way to either make the laser pause a bit, or delay while it punches through and vaporizes the material the same way it does for the rest of the cut… Im going to play with it now and see if it improves my cut, I suspect it will. I honestly set my min/max power settings to be the same because I dont understand what they do… obviously if they are both the same the laser is going to start and stop with the same amount of power throughout the cut, but I dont understand what the minimum power setting is for, I dont want a cut where part of the cut is done at a different power level because I feel like it would yield different results… Like, what determines at what point throughout the cut when the laser would use the minimum power parameter?

Min power is used when your laser is traveling slower than its ‘Start Speed’ (on Ruida, this is usually 10mm/sec, but it is a parameter you can change).

As the laser passes ‘Start Speed’ and ramps up to the cutting speed, power is ramped from Min Power to Max Power. This is really useful if you are doing surface engraving on wood, because the laser has to slow down for sharp corners. If it slows down without lowering the power, you get burnt points at the start / end of cuts and at corners.

For slow cutting, it’s generally best to set Min & Max to the same value. Some people get tripped up when they cut really slow, like 5mm/sec, and set Min Power lower than Max. Because the laser never passes the ‘Start Speed’, it never ramps the power up from the Min Power value, so people get confused.

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ah, ok, that makes a ton of sense now… and yes, that has messed me up quite a few times in the past… Ill post my results using the cut through mode and if my thinking is correct, it should nip this issue in the bud pretty quickly… The software itself is ultra intuitive and super handy, I should have known this was a feature, I just didnt know what it was called… I like how easy everything is to figure out for the most part, using a single person to ungroup for example, that was pretty instinctive, just really great software overall and I cant praise it enough… The ability to save jobs in the exact config for future use is huge for me, I produce alot of the same components and it really does take the guess work out of it… thanks for all your help :slight_smile:

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