Adjusting overscan on Ruida?

[Steve Utick]

Is it possible to adjust the amount of overscan on a ruida 644x controller? I've got two different lasers running ruida controllers, and one of them has a ton more overscan at similar speeds than the other, which leads to taking almost double the time to do a similar engraving project. Would like to see if I can tweak the overscan down a bit hopefully, just not sure where to look for the settings, or if it's even available.

Thanks!

[Ian Stewart-Koster]

Exactly what do you mean by 'overscan' ?
I can guess, but I might by wrong.
Is it scan interval in config, or X & Y offset in user parameters, or misalignment between scans and vector cust, or what, precisely?
I have our ruidas tuned pretty finely. but it took some work.

[Kev Williams]

I believe he's talking about the distance the laser travels beyond the extreme edges of what's engraving, not sure what controller is in my Triumph but at 800mm/second the 'overscan' (over-run?) was almost 4" on each end! --contrast that to my Gravograph machines, even running at 80" per second the over-run is less than 1/16" inch...

Awhile back I changed a few of my speed settings in the 'parameters' sections, those settings no one seems to know what they mean? Like Min-Acc, Cut-Acc, Cut-Acc-Acc, etc... Anyway, lowering some numbers made for nicer curve cuts, and I believe what I changed also affected the amount of over-run, but (a) I couldn't tell you what I changed exactly, and (b) I'm not REALLY sure it DID help! ;)

I know what CAN help, depending on what you're engraving; in particular, the length of the engraving you're doing... example, if you're running 1" x 4" plates by column, running at 500mm/s may seem faster than 250mm/s, but at 250 the over-run is MUCH less than at 500, so 250 will likely engrave faster. Just be sure to adjust power... :)

If you're running long lengths in one sweep with little 'white space', then run as fast as practical...

[Steve Utick]

I believe he's talking about the distance the laser travels beyond the extreme edges of what's engraving, not sure what controller is in my Triumph but at 800mm/second the 'overscan' (over-run?) was almost 4" on each end! --contrast that to my Gravograph machines, even running at 80" per second the over-run is less than 1/16" inch...

Awhile back I changed a few of my speed settings in the 'parameters' sections, those settings no one seems to know what they mean? Like Min-Acc, Cut-Acc, Cut-Acc-Acc, etc... Anyway, lowering some numbers made for nicer curve cuts, and I believe what I changed also affected the amount of over-run, but (a) I couldn't tell you what I changed exactly, and (b) I'm not REALLY sure it DID help! ;)

I know what CAN help, depending on what you're engraving; in particular, the length of the engraving you're doing... example, if you're running 1" x 4" plates by column, running at 500mm/s may seem faster than 250mm/s, but at 250 the over-run is MUCH less than at 500, so 250 will likely engrave faster. Just be sure to adjust power... :)

If you're running long lengths in one sweep with little 'white space', then run as fast as practical...

Kev is 100% correct, I'm talking about the distance the head travels past the edges of the engraving. Our CamFive machine at 500mm/s will travel about 1/2" past but our Boss laser will travel about 3" Makes a huge difference in engraving time. Have only had Lightburn on our Boss, so going to fire up the factory RDWorks and dig around in settings today and see what I can figure out to try and tighten it up a bit.

[Steve Utick]

Kev is 100% correct, I'm talking about the distance the head travels past the edges of the engraving. Our CamFive machine at 500mm/s will travel about 1/2" past but our Boss laser will travel about 3" Makes a huge difference in engraving time. Have only had Lightburn on our Boss, so going to fire up the factory RDWorks and dig around in settings today and see what I can figure out to try and tighten it up a bit.


OK, wanted to follow up on this. Sat down with both lasers and started comparing things yesterday. Not the easiest thing, as one uses SmartCarve as it's native software and the other RDWorks. But, I did find an answer. Messed around with some parameters in the password protected settings section, and didn't seem to make any difference. Then, I started playing with the acceleration numbers in the User settings tab in RDWorks. Turns out that the Acceleration on our CamFive machine is set to 10,000mm/s2, which appears to be the max acceleration that is allowed by what's programmed in the controller from the factory. The acceleration on the Boss was set to 2,000mm/s2. Cranked it up to 10,000 which is also the max acceleration allowed, and it now has much less overscan and the time to engrave is almost identical to the other laser.

[Kev Williams]

Well, THAT'S cool, that you figured out what some of those sets of numbers mean! :D

I haven't played with those high-accel numbers myself, going to have to experiment!

--do yourself a favor and verify the engraving quality- that you need at least- isn't affected by the reduced startup/slowdown times you changed. The stepper's SHOULD handle the extra shock, but if they try to move or stop the lens head too quickly, the weight of the head could cause the stepper to skip...

[Ian Stewart-Koster]

Sorry, I've not been back to check up on this, but now I understand what you meant, I could have answered your question: the higher the possible acceleration, the shorter the turn-around space needed. But there can be compromises, depending on other variables in your system, like overshoot when cutting.

I did a big analysis and posted it in the facebook Lightburn group about 4 or 5 months ago, as I was tuning out big laser into compliance - on our case, with high accelerations came appalling wobble and lack of accuracy in fine text or fine shapes when vector cut.
I also did some engraving, (as in 8 ft x 4 ft approx) and worked out, from memory, depending on the power, speeds above 350 mm/s were ineffective in reaching the end of the job more quickly, or in getting greater detail. Lesser speeds took longer and gave no better detail. Higher speeds lost detail, and did not really improve on total time by more than a few percent. For our 2 chinese machines that is.

Eg one scanning job took 32 minutes to complete at 350 mm/s, but took 30.5 minutes at 400 mm/s. Not much time gain for a 12% speed increase - because it relates to acceleration - and I needed accuracy more than speed there.

A lot of the oddly named user parameters and vendor settings, I figured out also, and had to tweak them one at a time to achieve the accuracy I needed.
It was a LONG learning curve, and much step retracing...

[Steve Utick]

Well, THAT'S cool, that you figured out what some of those sets of numbers mean! :D

I haven't played with those high-accel numbers myself, going to have to experiment!

--do yourself a favor and verify the engraving quality- that you need at least- isn't affected by the reduced startup/slowdown times you changed. The stepper's SHOULD handle the extra shock, but if they try to move or stop the lens head too quickly, the weight of the head could cause the stepper to skip...

That was all part of my testing process as well, doing some test engravings to ensure that I wasn't messing with engraving quality, etc. Overall, I'm happy with the changes, has cut the engraving time down to acceptable times, and everything looks on par with what it was before.

[Steve Utick]

Sorry, I've not been back to check up on this, but now I understand what you meant, I could have answered your question: the higher the possible acceleration, the shorter the turn-around space needed. But there can be compromises, depending on other variables in your system, like overshoot when cutting.

I did a big analysis and posted it in the facebook Lightburn group about 4 or 5 months ago, as I was tuning out big laser into compliance - on our case, with high accelerations came appalling wobble and lack of accuracy in fine text or fine shapes when vector cut.
I also did some engraving, (as in 8 ft x 4 ft approx) and worked out, from memory, depending on the power, speeds above 350 mm/s were ineffective in reaching the end of the job more quickly, or in getting greater detail. Lesser speeds took longer and gave no better detail. Higher speeds lost detail, and did not really improve on total time by more than a few percent. For our 2 chinese machines that is.

Eg one scanning job took 32 minutes to complete at 350 mm/s, but took 30.5 minutes at 400 mm/s. Not much time gain for a 12% speed increase - because it relates to acceleration - and I needed accuracy more than speed there.

A lot of the oddly named user parameters and vendor settings, I figured out also, and had to tweak them one at a time to achieve the accuracy I needed.
It was a LONG learning curve, and much step retracing...


At least in the Ruida controllers, there are separate acceleration numbers for Scanning and cutting. I was only changing the numbers in the scanning section, so I don't think it should make any difference in cut precision in my case, or at least I haven't seen any differences yet. Thanks for the input though. Would like to see your analysis you did if you would be able to send private or something, as I don't facebook.

[Ian Stewart-Koster]

Steve, I'd need to start afresh, as it grew into a thread of about 35 or 45 posts, with photos and explanations...
but maybe I can redo it, and make it more concise, and post it here - good idea.
(but it won't be this week!)

[Steve Utick]

Steve, I'd need to start afresh, as it grew into a thread of about 35 or 45 posts, with photos and explanations...
but maybe I can redo it, and make it more concise, and post it here - good idea.
(but it won't be this week!)

Completely understand. Thanks.