I’m new to the world of Lasers. A while ago I managed to pick up a used, Blue and White generic Chinese 50w Laser, branded VEVOR.
The tube was from 2019 and well used, judging by the smoke residue left on it. Expecting the tube to fail soon I brought a new one, from the same company my machine was from.
Obviously the tube failed just as I really needed it. Making me have to spend my evening installing the new one. The new tube did not come with any connectors, only two small metal pins on each end. The old tube also did not have any connectors. So I just cut the wires close to the tube and connected them to the new tube using Luster terminals, wrapped with some electrical tape to prevent arcing. But apparently not well enough and as soon as I tried a test cut the tube arced and damaged the PSU. Having me to buy and installed a new one, also from VEVOR.
Which brings me to my current problem. The analog mA meter on my machine is showing a very high mA draw even at a relative low power setting.
At 30% power in Lightburn it’s already at 20mA on the meter. On the old tube i would only reach that high with something like 70% power.
I’m afraid of going over 40% currently in case I damage the tube but also feel like I am not getting the Laser power I should be.
Could this be an issue with the mA meter or is my tube bad?
We know the class of the machine as it’s got a Ruida controller.
The cathode or ground side of the tube goes through the mA meter. The anode is the high voltage and needs to be insulated from the laser power supply to the tube or it will arc to the coolant or case, whichever has the least inductance.
Did it arc to the case? If so, it would bypass the mA meter if connected properly and it would read nothing.
You’re going to have to post some photos of what’s there and what you’ve done as a correction.
Be realistic about the machines power. Here’s a chart that appears to give good results. I had a 50W China Blue, that had a tube length of 880mm, so it produced about 43W with a Mahoney watt meter. Just measure the length of your tube.
Both sides are still connected with Luster terminals but now there is plastic tube over them filled with acryl and then wrapped with electrical tape. I also put some rubber foam sheets in there to further insulate it.
I’m now paranoid about arcing to the coolant. Is there a way I can tell if that is the case? And or a better, more professional way to connect the tube? Should I have used silicone to fill the tubes instead of Acryl?
Here’s mine, showing the anode end (high voltage). You can see the double insulation and connection that the factory installed, red, before shipping it to me. Good electrical tape doesn’t work at the 30kV values your lps is using.
Those connectors look sweet! But I can not find any I can just buy.
I watched a video where they soldered the cable directly onto the pin. Is this recommended? I am hesitant about soldering so close to glass as the heat could possibly crack the tube.
I know my tube is not orientated correctly as I’m still worried about arcing.
Usually the connections to the tube have had short pre-attached wires to the anode. There is putty that you can get for hv application that would allow you to wrap it around the connection.
Even a piece of clear tubing has pretty high insulating effect, higher than electrical tape.
