Engraving issue after upgrade.

[elkae.graphics]

I've upgraded my Shenhui 350 to a new 40-60w LPSU and SP 45w tube purchased through the LightObject website. After installing, and getting used to the (now) more powerful laser, I began to notice an issue where the laser is not 'starting' each pass with full power.

Below I've attached an image of the results. Sent a file via RDworks 20mm x 20mm . and you can see each stroke there is a delay of 'full' power . I increased the distance between each pass to separate them and make the difference more pronounced. Speed of the pass is 400mm/s with interval(mm) of 0.4. Same issues when sending a 5mm x 20mm file [next to it].

With a higher 'resolution' engraving, this results in the edges of the engraving being shallower/not as dark as the centers of engraved area.

This issue was not present before switching out the power supply / laser tube. Any assistance would greatly be appreciated.

[Tech_Marco]

Larry:

I haven't your case but everyone in China was on holiday since Jan 30 until Feb 17 and I could get a hold with two professionals. All three guys came up similar answer but not exact.

1) All three of them agreed that it was a 'backslash' issue. Something caused by the machine. On your controller card, you can make some adjustment to offset it

2) One of three came up more detail info. Beside backslash, he said that it could be latency from the laser tube. How to tell: measure each line and checked if lines having correct length from the engraving? If all lines have correct length from the engraving, then the problem is sure from the machine. If it is shorter, then it could be delay from the tube. You may adjust some setting to offset it

I think you're using RD controller board. Of that , there are a lot parameters need to setup to make better job. Some like RD controller bard for it's complexity (may be better result) but some like LO-X7 with easy use. I think most laser tube has latency but it shouldn't happen so worst in your case. If you asked me and I'll say that it should be mechanical issue and setting issue. Remember that the laser tube is a small tube, 1m long, right? If so, the delay from a tube should be ignored. May be a bad power supply, I really can't tell at this stage. So, double check the parameters setting see if you can find some hints.


Marco

[elkae.graphics]

Thanks for the reply Marco, The width of each pass is short. It is likely a latency issue with the laser / power supply. Is there a way to offset latency?

[Tech_Marco]

Sorry for the late reply. We're doing remodeling on our office kitchen.

Anyway, you may want to download the manual and review it. I was told that there was a setting for the backslash or delay could be adjusted.

BTW, I still think that this is an issue on your machine somewhere. I tested a tube and the similar power supply with 1500mm/s engraving sped, I could hardly seem any missing spot. May be there were some but it was extremely small. At, 1000mm/s speed, no way I could find any possible missing dot.

Marco

[elkae.graphics]

I do not believe this is an issue with my machine, as I did not have this problem before installing the laser tube and power supply from your site. I've attached an image of some pulses I did. this is from directly off the laser, before the first mirror. This is from pressing the pulse button on controller at various time intervals. On my previous tube, it would be a solid circle. This one creates just a ring. Is this standard?

[elkae.graphics]

Can anyone else confirm if their pulse test off the laser looks like what I am getting above, or if yours is a solid circle.

[Tech_Marco]

If you have low current, the laser burn would be a 'ring'. But if current is high enough to be fully enegizied, it would be solid.
The tube should be running in stable condition if current is set to 5mA or higher.

I tried similar laser tube with speed at 1000mm/s and I couldn't duplicate the problem you have. At 1500mm/s, I may see less than 0.5mm offset but at that speed a regular laser machine can't reach.


Marco

[Tech_Marco]

Update: if you think that the problem is from our tube. You can send it back to let us to trouble shooting it.
If it is an issue from the tube, we will send you a new tube at our cost. But if it is not, you need to issue a return shipping label to return the tube to ship back to you


Marco

[elkae.graphics]

I can bring both the power supply and laser tube by as I live in Sacramento.

[Tech_Marco]

Bring it on Friday around 10am

Marco

[PeterE]

I would love an update on this. One of my customers (I do workshops for them) have bought a laser from a large re-seller and it has decline into uselessness.
When I tested calibration on it I also only got a circle and not a solid. The output was correct in the amount of power, but it was impossible to focus it into anything useful!

If my advice could simply be: "get a new tube" - that would be so much easier for them (and I would score some credit).

Peter.

[elkae.graphics]

Update:

Swung by the LO office today with the laser tube and power supply. Was able to meet one of the techs, and also Marco himself. Spent some time setting up one of their demo machines just to test my laser tube and PS. First test pass at the same settings from my machine, and the issue was replicated on their machine. Then we proceeded to isolate the issue. First swapping power supplies as it was the easiest of the two to swap. With a new PS installed, another test engraving was ran and still same results. That ruled out the power supply as possibly being defective. Next they swapped out the laser tube with another one. After aligning the mirrors, and with fingers crossed, we ran another test engraving. BOOM! (figuratively) the latency issue was gone! Marco ran a couple other test engravings and various settings to make sure I was satisfied with the results. Packed up the new tube along with my power supply and I was on my way.

I had an issue that Marco even stated in previous posts as never been seen before. But through their awesome customer service and willingness to go the extra mile to fully diagnose and resolve the issue, I left completely satisfied and even with Marco learning something new today haha. Tube and PS are now reinstalled into my machine and things are running flawlessly.

Thanks guys at LO! I would never hesitate to send anyone in the lasering community your way. Top notch customer service.

PeterE: With the new tube installed, test fires now result in solid circles. Whether or not that is a related issue, I can not verify. But with the new tube, that is the difference I see vs the previous one. That along with the latency issue.

[PeterE]

Thank you very much for the update, Elkae Graphics.

So a tube issue - possibly with the exit crystal - nice to know! I will inform my client that they will need to proceed with a warranty case for a replacement tube.

I will win some brownie points for that.

Peter