laser help

[amanda piper]

Hi all, I brought a 50w co2 laser from ebay in december. from this seller http://wwwdotebaydotcodotuk/usr/hotitemsale?_trksid=p2053788.m1543.l2754. Supposidly with a 2 year warranty (ha ha i wish)! He will not reply to any of my messages now. Anyway I've used it 49 hours and having a few problems. The laser seemed to be getting weaker and weeker. I now cant cut out anything apart from paper!
When i try and pulse it to check alignment, Sometimes it burns a mark straight away, other times takes ages to get any kind of mark. When i engrave it will faintly do some of the writing that i want and not others but then if i delete what it did do faintly it will engrave the bits that it missed. I tried yesterday to cut some writing at 100 speed and 99% power and it scored the mdf wood not too bad but at 100% it wasn't fantastic. Then i put a piece of mdf in the same place and tried to scan the same thing and it came out so faint. I'm using rdworks.
Can anyone help me please. I'm only using it as a hobby for the minute and doing things for family and friends and i was really enjoying learning. I dont have any idea about electrics etc so i cant test anything properly. I did have someone try and look as i couldn't get the pulse to work. He bypassed the controller and powered the tube from the power box and it worked fine making the marks for alignment. 320389 here is a pic of my laser using the cut and then the scan.
If anyone can help me i would be truly grateful.
Thanks in advance for reading this.
Amanda

[Jerome Stanek]

Have you cleaned the mirrors and lens. how about alignment. could the beam be hitting the side of the lens tube.

[John Noell]

I'd strongly recommend reading the many posts here about Chinese lasers, especially those concerning power. Have you been running anywhere near 100%? If so, your are probably over-driving the tube, killing it.

[Clark Pace]

First thing I would do is engrave the exact same thing and see if it fades in the same space. Put your piece in the same position also. It's very possible that you beam is aligned better towards and as it engraves down the table it's off alignment.

So basically would another engrave look the same. Faded in the same parts.

[Ross Moshinsky]

I have to ask, what made you buy a laser from someone that also sells sausage fillers, 80cc engines, and snow cone makers? I would contact your CC company and file a dispute immediately but you're probably out of luck due them being in China. Shipping in China is heavily subsidized which is why they can ship something 100lbs for $100 and to make the same shipment from the US or UK would probably cost 5x that.

As for figuring out your problem, there are a few things to look at.

1. Alignment. This could be as simple as adjusting the mirrors or as complicated as a "tweaked" machine.
2. Check the table level. Again, simple as adjusting the screws or as complicated as a "tweaked" machine.
3. Verify the power supply and tube are working correctly. Search and you should be able to find several ways to check on both.

If you're not into figuring out why your machine doesn't work right, HPC Laser is located in the UK. I believe they will fix machines that aren't theirs. Don't be surprised if fixing the machine costs about what you spent for it.

[Keith Winter]

Lol Ross! But sausage fillers, snow cone makers, and lasers are pretty much the same thing right? :)

[amanda piper]

Thank you i will try some of your suggestions. Jerome i have cleaned the mirrors and lens. If the beam is hitting the side of the tube would that mean i need a new tube? Or could i try and adjust it somehow? John no i havent been using the machine at 100% i only tried that yesterday. I normally run it 30-40%. Higher if trying to cut out a thin bit of mdf.
Ross when we decided to take the plunge last year and buy a machine the seller was selling lots of different machines with lots of different parts for sale too. He had good feedback and didnt seem to have much other stuff for sale. He was really good communication wise before buying and after buying gave me tracking numbers and machine was delivered within 3 days. He gave me answers about the rdworks and adviced on graphics programs etc. He seemed to know his stuff. What would i say to my cc company as they originally said when i called them that they couldnt get involved and give me the money back as the warranty is not with them so they dont have to refund my money.
I originally went to hpc to look at their lasers! They were helpful whilst there. We didnt buy their machine as i got a quote from their office then i rang twice and emailed to ask for a higher watt tube than what they supplied (which the engineer said would be ok) but they never got back to me. Then i brought this machine from ebay and thought well for 1.5k i was saving alot of money but obviously at the min i feel its good for scrapping!!!!
Thanks for all your help. I will try checking the table level, lens and mirrors again and will check for the power to see about checking it. I really appreciate the help from you all and if you have any more suggestions please let me know.
Thanks
Amanda x

[Walt Langhans]

"If the beam is hitting the side of the tube would that mean i need a new tube?"

Do you mean inside of the tube, like it's arcing?

[Clark Pace]

"If the beam is hitting the side of the tube would that mean i need a new tube?"

Do you mean inside of the tube, like it's arcing?


So I had that problem, with 2 lasers. There was arcing leaving the tube hitting the metal wall. The company gweike sent me a rubber shield that wrapped around the end of the tube(opposite end of where the laser fires. They said I should have had that installed when I setup the laser.) If the energy is leaving the tube and hitting the walls. You are losing a lot of power.

That sold the problem. On my other laser(first china laser from years ago) I ended up buying some cermaic tiles and lining the inside of where the tube fits. The stopped the arcing. It was a sub $1000 laser the $500.

[Jerome Stanek]

No I the tube the lens is mounted it at the nozzle after it runs a while stop it and feel the nozzle and see if it is hot.

[Kristopher Powers]

Lol Ross! But sausage fillers, snow cone makers, and lasers are pretty much the same thing right? :)

:-( I did not see any snow cone or lasers but i did see a 400W wind generator :D.

[Bill George]

If we could just get these folks here to read for a couple of weeks before they buy that eBay laser. No local support and now she is stuck with a machine she can't use and does not understand how to fix. If the vender delivered the machine in 3 days he must of had it stock and not in China. She did not say where she was located?

My guess is dirty or even loose mirrors, and I have had the lens in the tube be really loose and cause the same kind of problem.

[Dave Sheldrake]

You in the UK Amanda? if so you are more than welcome to call or text and I'll see if I can help.

A couple of questions?

1: Is the cone on the end where the beam comes out getting warm or hot?
2: How flat is the material you are engraving?

It seems to band from left / middle / right suggesting the focus is going out over a higher or lower area? the lines look thicker in the middle as well.

Alignment will usually chuck things out from left to right or top to bottom (or both) it's unusual for alignment to be in then out then in again over the width of the table.